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1.
Nature ; 615(7954): 813-816, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36991189

RESUMO

The proton is one of the main building blocks of all visible matter in the Universe1. Among its intrinsic properties are its electric charge, mass and spin2. These properties emerge from the complex dynamics of its fundamental constituents-quarks and gluons-described by the theory of quantum chromodynamics3-5. The electric charge and spin of protons, which are shared among the quarks, have been investigated previously using electron scattering2. An example is the highly precise measurement of the electric charge radius of the proton6. By contrast, little is known about the inner mass density of the proton, which is dominated by the energy carried by gluons. Gluons are hard to access using electron scattering because they do not carry an electromagnetic charge. Here we investigated the gravitational density of gluons using a small colour dipole, through the threshold photoproduction of the J/ψ particle. We determined the gluonic gravitational form factors of the proton7,8 from our measurement. We used a variety of models9-11 and determined, in all cases, a mass radius that is notably smaller than the electric charge radius. In some, but not all cases, depending on the model, the determined radius agrees well with first-principle predictions from lattice quantum chromodynamics12. This work paves the way for a deeper understanding of the salient role of gluons in providing gravitational mass to visible matter.

2.
Nature ; 594(7864): 513-516, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34163054

RESUMO

Dragging of light by moving media was predicted by Fresnel1 and verified by Fizeau's celebrated experiments2 with flowing water. This momentous discovery is among the experimental cornerstones of Einstein's special relativity theory and is well understood3,4 in the context of relativistic kinematics. By contrast, experiments on dragging photons by an electron flow in solids are riddled with inconsistencies and have so far eluded agreement with the theory5-7. Here we report on the electron flow dragging surface plasmon polaritons8,9 (SPPs): hybrid quasiparticles of infrared photons and electrons in graphene. The drag is visualized directly through infrared nano-imaging of propagating plasmonic waves in the presence of a high-density current. The polaritons in graphene shorten their wavelength when propagating against the drifting carriers. Unlike the Fizeau effect for light, the SPP drag by electrical currents defies explanation by simple kinematics and is linked to the nonlinear electrodynamics of Dirac electrons in graphene. The observed plasmonic Fizeau drag enables breaking of time-reversal symmetry and reciprocity10 at infrared frequencies without resorting to magnetic fields11,12 or chiral optical pumping13,14. The Fizeau drag also provides a tool with which to study interactions and nonequilibrium effects in electron liquids.

3.
Nature ; 587(7832): 63-65, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33149293

RESUMO

Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown physical origin observed at extragalactic distances1-3. It has long been speculated that magnetars are the engine powering repeating bursts from FRB sources4-13, but no convincing evidence has been collected so far14. Recently, the Galactic magnetar SRG 1935+2154 entered an active phase by emitting intense soft γ-ray bursts15. One FRB-like event with two peaks (FRB 200428) and a luminosity slightly lower than the faintest extragalactic FRBs was detected from the source, in association with a soft γ-ray/hard-X-ray flare18-21. Here we report an eight-hour targeted radio observational campaign comprising four sessions and assisted by multi-wavelength (optical and hard-X-ray) data. During the third session, 29 soft-γ-ray repeater (SGR) bursts were detected in γ-ray energies. Throughout the observing period, we detected no single dispersed pulsed emission coincident with the arrivals of SGR bursts, but unfortunately we were not observing when the FRB was detected. The non-detection places a fluence upper limit that is eight orders of magnitude lower than the fluence of FRB 200428. Our results suggest that FRB-SGR burst associations are rare. FRBs may be highly relativistic and geometrically beamed, or FRB-like events associated with SGR bursts may have narrow spectra and characteristic frequencies outside the observed band. It is also possible that the physical conditions required to achieve coherent radiation in SGR bursts are difficult to satisfy, and that only under extreme conditions could an FRB be associated with an SGR burst.

4.
Nature ; 575(7781): 147-150, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31695211

RESUMO

Elastic electron-proton scattering (e-p) and the spectroscopy of hydrogen atoms are the two methods traditionally used to determine the proton charge radius, rp. In 2010, a new method using muonic hydrogen atoms1 found a substantial discrepancy compared with previous results2, which became known as the 'proton radius puzzle'. Despite experimental and theoretical efforts, the puzzle remains unresolved. In fact, there is a discrepancy between the two most recent spectroscopic measurements conducted on ordinary hydrogen3,4. Here we report on the proton charge radius experiment at Jefferson Laboratory (PRad), a high-precision e-p experiment that was established after the discrepancy was identified. We used a magnetic-spectrometer-free method along with a windowless hydrogen gas target, which overcame several limitations of previous e-p experiments and enabled measurements at very small forward-scattering angles. Our result, rp = 0.831 ± 0.007stat ± 0.012syst femtometres, is smaller than the most recent high-precision e-p measurement5 and 2.7 standard deviations smaller than the average of all e-p experimental results6. The smaller rp we have now measured supports the value found by two previous muonic hydrogen experiments1,7. In addition, our finding agrees with the revised value (announced in 2019) for the Rydberg constant8-one of the most accurately evaluated fundamental constants in physics.

5.
Clin Radiol ; 79(6): e826-e833, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38582634

RESUMO

AIM: To investigate whether dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has the potential to non-invasively detect microenvironmental condition by quantitatively measuring blood perfusion, vessel wall permeability, and vascularity, and to elucidate the possible correlations between DCE-MRI quantitative parameters and the expression level of hypoxia, vascularity, and cell proliferation related molecular biomarkers. MATERIALS AND METHODS: In this prospective single center clinical study, 58 patients diagnosed with cervical cancer underwent DCE-MRI before anticancer treatment were enrolled. Ktrans, Kep, Ve, and Vp were generated from Extended Toft's model. Then patients conducted colposcopy biopsy within 1 week after DCE-MRI. Pretreatment expression levels of HIF-1α, VEGF and Ki-67 were assessed and scored by immunohistochemistry on colposcopy obtained tumor specimens. RESULTS: In HIF-1α low-expression group, Ktrans (p=0.031) and Kep (p=0.012) values were significantly higher than the high-expression group. In VEGF high-expression group, Ktrans (p=0.044) and Ve values (p=0.021) were significantly higher than the low-expression group. In Ki-67 high-expression group, Ktrans (p=0.026) and Kep (p=0.033) were significantly higher than the low-expression group. Multiple linear regression analyses and Pearson correlation revealed that Ktrans independently negatively correlated with HIF-1α expression, Ve independently positively correlated with VEGF, and Kep independently positively correlated with Ki-67. The area under the ROC curves of Ktrans for HIF-1α, Ve for VEGF, and Kep for Ki-67 were 0.728, 0.743, 0.730, respectively. CONCLUSION: Our results suggest that DCE-MRI quantitative parameters could be potentially used as imaging markers for non-invasively detecting microenvironmental hypoxia, vascularity and proliferation in cervical cancer patients.


Assuntos
Biomarcadores Tumorais , Subunidade alfa do Fator 1 Induzível por Hipóxia , Antígeno Ki-67 , Neoplasias do Colo do Útero , Fator A de Crescimento do Endotélio Vascular , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Biomarcadores Tumorais/metabolismo , Meios de Contraste , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Antígeno Ki-67/metabolismo , Imageamento por Ressonância Magnética/métodos , Estudos Prospectivos , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/irrigação sanguínea , Fator A de Crescimento do Endotélio Vascular/metabolismo
6.
Clin Radiol ; 79(4): e539-e545, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38160106

RESUMO

AIM: To investigate the feasibility of non-enhanced and free-breathing whole-heart magnetic resonance coronary angiography (MRCA) using multishot gradient-echo planar imaging (MSG-EPI). MATERIALS AND METHODS: In total, 29 healthy volunteers were recruited for free-breathing whole-heart MRCA acquisition using the MSG-EPI sequence and fast gradient echo (GRE) sequence. After the examination, the actual scanning times, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) of the left main (LM) coronary artery, subjective quality scores for each segment, and evaluable length of the coronary artery were recorded and statistically analysed. RESULTS: There was no significant difference between the SNRLM of the MSG-EPI sequence and fast GRE sequence (p=0.130), but the CNRLM of the MSG-EPI sequence was higher (p=0.001). The subjective quality score of the mid- and distal left anterior descending branch as well as the distal circumflex branch of the coronary artery in the MSG-EPI sequence was higher than that in the fast GRE sequence (p=0.003, 0.001, and 0.003, respectively). The evaluable length of the left anterior descending branch and the circumflex branch was better using the MSG-EPI sequence than that of the fast GRE sequence (p=0.015 and < 0.001, respectively). Moreover, the scanning time of the MSG-EPI sequence was 54.5% less than that of the fast GRE sequence (p<0.001). CONCLUSION: The MSG-EPI sequence improves the subjective and objective image quality of MRCA as well as reduces the scanning time.


Assuntos
Imagem Ecoplanar , Coração , Humanos , Imagem Ecoplanar/métodos , Estudos de Viabilidade , Angiografia Coronária , Angiografia por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Imageamento por Ressonância Magnética
7.
Zhonghua Nei Ke Za Zhi ; 63(4): 371-377, 2024 Apr 01.
Artigo em Zh | MEDLINE | ID: mdl-38561282

RESUMO

Objective: To explore the variables associated with the severity of coronavirus disease 2019 (COVID-19) caused by the SARS-CoV-2 omicron variant during the epidemic in patients with myeloproliferative neoplasms (MPN). Methods: A cross-sectional study. During the SARS-CoV-2 omicron variant pandemic from December 15, 2022, to March 15, 2023, COVID-19 related data for patients with MPN who were treated at Peking University People's Hospital were collected through an online questionnaire-based survey. All questionnaires and clinical data were checked by medical assistants. Logistic multivariate analysis was used to explore the prevalence and variables associated with the severity of COVID-19 in patients with MPN. Results: A total of 239 patients with MPN, including 90 (37.7%) presenting with essential thrombocythemia (ET), 50 (20.9%) with polycythemia vera (PV), and 99 (41.4%) with myelofibrosis (MF), were enrolled in the study. The 99 patients with MF included 87 (87.9%) with primary MF, 5 (5.1%) with post-PV MF, and 7 (7.1%) with post-ET MF. Overall, 239 (100%) patients reported that they experienced COVID-19 during the pandemic. Of these, 226 (94.6%) had mild disease, 4 (1.7%) had moderate disease, 7 (2.9%) had severe disease, and 2 (0.8%) had critical disease. Two (0.8%) patients with severe COVID-19 died, one of which suffered from MT and the other from PV. Multivariate analysis showed that older age (OR=2.36, 95%CI 1.24-4.49), MF (OR=10.22, 95%CI 1.13-92.80), or comorbidity (OR=5.25, 95%CI 1.25-22.03) were associated with a significantly higher risk of developing moderate, severe, or critical COVID-19. Among patients with MF, higher risk stratification reflected an increased risk of developing moderate, severe, or critical COVID-19 (P=0.034). Conclusion: During the omicron pandemic, older age, MF (especially higher-risk categories), and comorbidity were associated with a higher risk of developing moderate, severe, or critical COVID-19.


Assuntos
COVID-19 , Transtornos Mieloproliferativos , Policitemia Vera , Mielofibrose Primária , Humanos , SARS-CoV-2 , Estudos Transversais , Transtornos Mieloproliferativos/epidemiologia , Inquéritos e Questionários
8.
Zhonghua Yi Xue Za Zhi ; 104(20): 1831-1836, 2024 May 28.
Artigo em Zh | MEDLINE | ID: mdl-38782751

RESUMO

Objective: To explore the feasibility of endoscopic lymph node dissection(LND) with programmed breast approach for the treatment of papillary thyroid cancer. Methods: A case series study. The clinical data of 39 patients with papillary thyroid cancer who underwent endoscopic LND treatment with programmed breast approach in Shenzhen People's Hospital from January to November 2022 were retrospectively analyzed. There were 10 males and 29 females, aged (35.95±10.17) years. LND time, total surgical time, intraoperative bleeding volume, postoperative drainage volume, postoperative hospital stay and postoperative complications were analyzed. Results: Among 39 patients, there were 18 cases of unilateral thyroid cancer, 21 cases of bilateral thyroid cancer, 35 cases of unilateral LND, and 4 cases of bilateral LND. The maximum diameter of thyroid cancer lesions was (1.48±0.69) cm, and the maximum diameter of lymph node metastases was (1.63±0.58)cm. The operative time of unilateral neck dissection was (124.11±19.92) min (102-170 min), and the total operative time was (226.42±55.68) min (110-390 min). The number of lymph nodes cleaned was (32.40±10.44)(12-54), the number of metastasis and detection was 207/1 393. The postoperative drainage volume was (174.64±82.33) ml(41-350 ml). There were no neck hematomas, no skin burns or no shrugging disorders in the postoperative period. There were 7 cases of numbness and discomfort in neck skin sensation, which gradually relieved after half a year. Postoperative discharge time (4.77±1.94) d(3-15 d). Conclusion: It is safe and feasible to treat papillary thyroid cancer with endoscopic LND with programmed breast approach, which can improve surgical efficiency and clinical application value.


Assuntos
Endoscopia , Estudos de Viabilidade , Esvaziamento Cervical , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide , Humanos , Feminino , Masculino , Adulto , Câncer Papilífero da Tireoide/cirurgia , Neoplasias da Glândula Tireoide/cirurgia , Estudos Retrospectivos , Esvaziamento Cervical/métodos , Endoscopia/métodos , Mama/cirurgia , Metástase Linfática , Excisão de Linfonodo/métodos , Complicações Pós-Operatórias , Duração da Cirurgia , Pessoa de Meia-Idade
9.
Zhonghua Bing Li Xue Za Zhi ; 53(6): 598-604, 2024 Jun 08.
Artigo em Zh | MEDLINE | ID: mdl-38825906

RESUMO

Objective: To investigate the clinicopathological, immunophenotypic and molecular genetic characteristics, and differential diagnosis of NTRK-rearranged spindle cell neoplasms (NTRK-RSCNs) in the gastrointestinal tract. Methods: Two NTRK-RSCNs diagnosed at the Department of Pathology of the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China and one case diagnosed at Zhengzhou Central Hospital, Zhengzhou, China from 2019 to 2022 were collected. The clinical data, histopathology, immunophenotypes and prognosis were analyzed. Fluorescence in situ hybridization (FISH) and next-generation sequencing (NGS) were used to detect NTRK gene rearrangements, while relevant literature was also reviewed and discussed. Results: Two patients were male and one was female, with the age of 17, 47 and 62 years, respectively. The tumors were located in the duodenum, ascending colon and descending colon, respectively. The tumors were protuberant masses with gray and rubbery sections. Their maximum diameter was 2.5, 5.0 and 10.0 cm, respectively. Histologically, the tumors invaded mucosa, intrinsic muscle and serosal adipose tissue. Tumor cells consisted of spindle or oval shaped cells with monotonous morphology and arranged in bundles or stripes pattern. Spindle cells were mildly to moderately atypical, with slightly eosinophilic cytoplasm and inconspicuous nucleoli. Necrosis and mitotic figures were observed in one high-grade tumor. All tumors expressed CD34, S-100 and pan-TRK in varying degrees. FISH analysis showed that NTRK1 gene was break-apart in 1 case and NTRK2 gene break-apart in 2 cases. NGS technologies showed LMNA::NTRK1 fusion in one case, STRN::NTRK2 fusion in another case. All patients recovered well after the surgery without recurrence at the end of the follow-up. Conclusions: NTRK-RSCN is rarely diagnosed in the gastrointestinal tract and has significant variations in morphology. It overlaps with various other mesenchymal tumors which should be considered as differential diagnoses. Be familiar with the features of histological morphology in combination with immunophenotype and molecular genetic characteristics can not only help diagnose NTRK-RSCNs, but provide therapeutic targets for clinical treatment.


Assuntos
Neoplasias Gastrointestinais , Hibridização in Situ Fluorescente , Receptor trkA , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Receptor trkA/genética , Receptor trkA/metabolismo , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/patologia , Adolescente , Rearranjo Gênico , Diagnóstico Diferencial , Sequenciamento de Nucleotídeos em Larga Escala , Receptor trkB/genética , Receptor trkB/metabolismo
10.
Zhonghua Bing Li Xue Za Zhi ; 53(6): 528-534, 2024 Jun 08.
Artigo em Zh | MEDLINE | ID: mdl-38825895

RESUMO

The STAR tool was used to evaluate and analyze the science, transparency, and applicability of Chinese pathology guidelines and consensus published in medical journals in 2022. There were a total of 18 pathology guidelines and consensuses published in 2022, including 1 guideline and 17 consensuses. The results showed that the guideline score was 21.83 points, lower than the overall guideline average (43.4 points). Consensus ratings scored an average of 27.87 points, on par with the overall consensus level (28.3 points). Areas that scored above the overall level were "conflict of interest" and "working groups", while areas that scored below the overall level were "proposals", "funding", "evidence", "consensus approaches" and "accessibility". To sum up, the formulation of pathology guidelines and consensuses in 2022 is not standardized, and the evidence retrieval process, evidence evaluation methods and grading criteria for recommendations on clinical issues are not provided in the formulation process; the process and method for reaching consensus are not provided, the plan is lacking, and registration is not carried out. It is therefore suggested that guidelines/consensus makers in the field of pathology should attach importance to evidence-based medical evidence, strictly follow guideline formulation methods and processes, further improve the scientific, applicable and transparent guidelines/consensuses in the field, and better provide support for clinicians and patients.


Assuntos
Consenso , Patologia , Publicações Periódicas como Assunto , Humanos , China , Medicina Baseada em Evidências , Patologia/normas , Publicações Periódicas como Assunto/normas , Guias como Assunto
11.
Zhonghua Jie He He Hu Xi Za Zhi ; 47(3): 296-300, 2024 Mar 12.
Artigo em Zh | MEDLINE | ID: mdl-38448186

RESUMO

The peak of COVID-19 infections in China has just passed, and symptomatic manifestations in patients vary widely, with a minority experiencing severe morbidity and mortality. Early detection of adverse outcomes remains critical for clinical governance and prognosis in COVID-19. This review synthesized both national and international studies relevant to the prognostic evaluation of COVID-19 and summarized the prognostic implications of demographics (age and gender), specific laboratory parameters, adjunctive examination results, complications, and comorbidities in COVID-19 patients. Pertinent laboratory parameters chiefly included markers of inflammation, coagulation function, and electrolytic balance. Adjunctive examinations included thoracic CT and electrocardiographic evaluations. Major complications and comorbid conditions included thrombotic episodes, co-infections, secondary infections, chronic pulmonary disorders, cardiovascular diseases, acute and chronic renal diseases, diabetes mellitus, and cerebrovascular accidents. Moreover, this article discussed how these elements affected the prognosis of patients with COVID-19. By summarizing the information, it aimed to inform preventive and therapeutic strategies against COVID-19 infections in the forthcoming period.


Assuntos
COVID-19 , Doenças Cardiovasculares , Coinfecção , Humanos , Prognóstico , China
12.
Zhonghua Gan Zang Bing Za Zhi ; 32(3): 214-221, 2024 Mar 20.
Artigo em Zh | MEDLINE | ID: mdl-38584102

RESUMO

Objective: To explore the drugs and clinical characteristics causing drug-induced liver injury (DILI) in recent years, as well as identify drug-induced liver failure, and chronic DILI risk factors, in order to better manage them timely. Methods: A retrospective investigation and analysis was conducted on 224 cases diagnosed with DILI and followed up for at least six months between January 2018 and December 2020. Univariate and multivariate logistic regression analyses were used to identify risk factors for drug-induced liver failure and chronic DILI. Results: Traditional Chinese medicine (accounting for 62.5%), herbal medicine (accounting for 84.3% of traditional Chinese medicine), and some Chinese patent medicines were the main causes of DILI found in this study. Severe and chronic DILI was associated with cholestatic type. Preexisting gallbladder disease, initial total bilirubin, initial prothrombin time, and initial antinuclear antibody titer were independent risk factors for DILI. Prolonged time interval between alkaline phosphatase (ALP) and alanine aminotransferase (ALT) falling from the peak to half of the peak (T(0.5ALP) and T(0.5ALT)) was an independent risk factor for chronic DILI [area under the receiver operating characteristic curve (AUC) = 0.787, 95%CI: 0.697~0.878, P < 0.001], with cutoff values of 12.5d and 9.5d, respectively. Conclusion: Traditional Chinese medicine is the main contributing cause of DILI. The occurrence risk of severe DILI is related to preexisting gallbladder disease, initial total bilirubin, prothrombin time, and antinuclear antibodies. T(0.5ALP) and T(0.5ALT) can be used as indicators to predict chronic DILI.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Doenças da Vesícula Biliar , Falência Hepática , Humanos , Estudos Retrospectivos , Fatores de Risco , Prognóstico , Bilirrubina
13.
Zhonghua Yan Ke Za Zhi ; 60(2): 147-155, 2024 Feb 11.
Artigo em Zh | MEDLINE | ID: mdl-38296320

RESUMO

Objective: This study aimed to observe the clinical efficacy of precise suturing of posterior elastic layer fissures guided by intraoperative optical coherence tomography (OCT) in conjunction with anterior chamber puncture and drainage, and corneal thermokeratoplasty for the treatment of severe acute edematous keratoconus. Methods: Non-randomized controlled trial. Data were collected for a study involving 31 cases of acute edematous keratoconus patients who underwent surgical treatment at the Shandong Eye Hospital between June 2017 and July 2021. Among them, there were 30 male and 1 female patients, with an age range of 11 to 32 years and a mean age of (19.80±5.80) years. Eighteen patients in the study group underwent precise suturing of posterior elastic layer fissures guided by intraoperative OCT, in combination with anterior chamber puncture and drainage, and corneal thermokeratoplasty. Thirteen patients in the control group did not undergo suturing. Preoperative visual acuity, corneal edema diameter, corneal thickness, and posterior elastic layer fissure length were collected. Evaluation was performed using slit lamp microscopy, anterior segment OCT, and other methods to assess the time of initial postoperative corneal edema resolution and closure of the posterior elastic layer fissure. Deep lamellar keratoplasty was performed 2 to 4 weeks after edema resolution, and the corneal bed scar repair and visual acuity of the two groups were compared. Results: In the suturing group, the corneas of all 18 patients were accurately sutured to the deep stromal layer near the posterior elastic layer. The time for corneal edema resolution was 2.50 (1.00, 6.25) days in the suturing group and 7.00 (6.00, 10.50) days in the control group. The fissure healing time was 7.50 (7.00, 12.00) days in the suturing group and 14.00 (9.00, 14.00) days in the control group. The differences were statistically significant (all P<0.05). After 2 weeks, the central corneal thickness decreased to (529.80±174.50) µm in the suturing group and (612.00±205.12) µm in the control group. The suturing group showed accurate corneal suturing to the deep stromal layer near the posterior elastic layer, resulting in central corneal flattening, closure of voids in the stroma, and a significant decrease in corneal thickness. All 18 patients in the suturing group successfully completed deep lamellar keratoplasty, with 6 cases (6/18) experiencing mild graft bed leakage during surgery but without affecting the deep lamellar keratoplasty. One year postoperatively, the visual acuity (logarithm of the minimum resolution angle) was 0.23±0.12 in the suturing group and 0.33±0.11 in the control group, with a statistically significant difference (P<0.05). Conclusions: In the treatment of severe acute edematous keratoconus, precise suturing of posterior elastic layer fissures guided by intraoperative OCT, in conjunction with anterior chamber puncture and drainage, and corneal thermokeratoplasty, can rapidly alleviate corneal edema and promote the healing of posterior elastic layer fissures. This approach achieves better visual outcomes for subsequent lamellar keratoplasty surgeries. The use of intraoperative OCT guidance allows accurate positioning of the posterior elastic layer fissure in terms of location, direction, and depth of corneal stromal voids, thereby assisting surgeons in precise suturing.


Assuntos
Edema da Córnea , Transplante de Córnea , Ceratocone , Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Adulto , Criança , Ceratocone/cirurgia , Tomografia de Coerência Óptica/métodos , Edema da Córnea/cirurgia , Córnea/cirurgia , Suturas
14.
Zhonghua Xin Xue Guan Bing Za Zhi ; 52(2): 180-184, 2024 Feb 24.
Artigo em Zh | MEDLINE | ID: mdl-38326070

RESUMO

Objective: To compare the effects of left bundle branch area pacing (LBBaP) versus traditional right ventricular pacing (RVP) on left ventricular function in patients after dual-chamber pacemaker implantation. Methods: A retrospective cohort study was conducted on patients who underwent dual-chamber pacemaker implantation from March 2017 to April 2021 in Beijing Anzhen Hospital. The patients were divided into the LBBaP group and RVP group based on the placement of the ventricular lead. Follow-up was conducted until March 2022, comparing baseline and follow-up echocardiographic parameters, pacing parameters, and the incidence and timing of complications between the two groups. The complications included ventricular electrode perforation, dislocation, pericardial effusion, tricuspid valve perforation, etc. Results: A total of 163 patients aged (68.3±13.5) years were included, including 82 (50.3%) men, with 80 patients in the LBBaP group and 83 in the RVP group. Baseline left ventricular end-diastolic diameter ((50.49±4.95) mm vs. (47.43±8.15) mm, P=0.01) and left atrium (LA) ((33.14±5.94) mm vs. (30.18±3.92) mm, P=0.001) in the LBBaP group were significantly higher than those in the RVP group. Follow-up LA diameter ((37.10±6.70) mm vs. (40.10±8.90) mm, P=0.016) showed a statistically significant difference in the LBBaP group compared to the RVP group. There was no statistically significant difference between the two groups in baseline QRS duration(P=0.490). Postoperative QRS duration in the LBBaP group was significantly lower ((110.69±24.01) ms vs. (139.65±29.85) ms, P<0.010). Intraoperative threshold in the LBBaP group was significantly higher ((0.83±0.32) V/0.48 ms vs. (0.71±0.23) V/0.48 ms, P=0.004), while impedance was lower ((754.53±205.59) Ω vs. (905.41±302.75) Ω, P<0.01). Comparing with the RVP group, postoperative ventricular pacing ratio (VP) ((87.39±20.92) % vs. (79.49±25.76) %, P=0.034), threshold ((0.90±0.38) V/0.48 ms vs. (0.69±0.27) V/0.48 ms, P<0.01) in the LBBaP group were higher, and impedance ((507.45±77.37) Ω vs. (620.52±197.29) Ω, P<0.01) in the LBBaP group was lower. Postoperative follow-up period was 5 to 51 months, with a median follow-up time of 17 months. No statistically significant difference in overall complications between the LBBaP and RVP groups was found (13.8% (11/80) vs. 7.2% (6/83), P>0.05). The median time to occurrence of complications after surgery was significantly earlier in the LBBaP group (29.74 (95%CI 27.21-32.26) months vs. 46.17 (95%CI 42.48-49.86) months, P=0.030). Conclusion: LBBaP demonstrates more stable pacing parameters, substantial improvement in clinical left ventricular function, with a relatively higher threshold compared to traditional RVP, and complications occurs relatively early.


Assuntos
Estimulação Cardíaca Artificial , Marca-Passo Artificial , Humanos , Masculino , Feminino , Estudos Retrospectivos , Fascículo Atrioventricular , Eletrocardiografia , Função Ventricular Esquerda , Resultado do Tratamento
15.
Opt Express ; 31(25): 41014-41025, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38087510

RESUMO

In recent years, significant progress has been made in the fields of nonlinear and ultrafast optics, offering exciting opportunities for terahertz (THz) science and technology. In this study, we present a novel design of a SSBCD (Solid-State-Biased Coherent Detection) device for the coherent detection of ultra-broadband THz pulses. By increasing the number of cross-fingers, we have effectively enhanced the sensitivity of the SSBCD device. The design of stepped and circular structures has successfully expanded the detectable electric field directions while reducing the dependence on the incident field direction. As a result, we have achieved ultra-broadband detection with a high dynamic range and a wide detection angle. These research findings lay a critical foundation for the integration of solid-state ultra-broadband detection into compact and miniaturized terahertz systems.

16.
Clin Radiol ; 78(12): 919-927, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37634989

RESUMO

AIM: To determine risk factors for portal venous system thrombosis (PVST) after partial splenic artery embolisation (PSAE) in cirrhotic patients with hypersplenism. MATERIALS AND METHODS: Between March 2014 and February 2022, 428 cirrhotic patients with hypersplenism underwent partial splenic artery embolisation and from these patients 208 were enrolled and 220 were excluded. Medical records of enrolled patients were collected. Computed tomography (CT) images were reviewed by two blinded, independent radiologists. Statistical analyses were performed by using SPSS. RESULTS: Progressive PVST was observed in 18.75% (39/208) of cirrhotic patients after PSAE. No significant differences in peripheral blood counts, liver function biomarkers, and renal function were observed between the patients with progressive PVST and the patients without progressive PVST. The imaging data showed significant differences in PVST, the diameters of the portal, splenic, and superior mesenteric veins between the progressive PVST group and non-progressive PVST group. Univariate and multivariate analysis demonstrated portal vein thrombosis, spleen infarction percentage, and the diameter of the splenic vein were independent risk factors for progressive PVST. Seventeen of 173 (9.83%) patients showed new PVST; the growth of PVST was observed in 62.86% (22/35) of the patients with pre-existing PVST. Spleen infarction percentage and the diameter of the splenic vein were independent risk factors for new PVST after PSAE. CONCLUSION: The present study demonstrated portal vein thrombosis, spleen infarction percentage, and the diameter of the splenic vein were independent risk factors for PVST after PSAE in cirrhotic patients with hypersplenism.


Assuntos
Hiperesplenismo , Hipertensão Portal , Trombose , Trombose Venosa , Humanos , Hiperesplenismo/complicações , Hiperesplenismo/diagnóstico por imagem , Veia Porta/diagnóstico por imagem , Veia Porta/patologia , Esplenectomia/efeitos adversos , Fatores de Risco , Trombose Venosa/complicações , Trombose Venosa/diagnóstico por imagem , Cirrose Hepática/patologia , Infarto/complicações , Infarto/patologia , Veia Esplênica/diagnóstico por imagem
17.
Zhonghua Nei Ke Za Zhi ; 62(4): 422-426, 2023 Apr 01.
Artigo em Zh | MEDLINE | ID: mdl-37032138

RESUMO

Objective: To observe the clinical effect of Qiliqiangxin capsule combined with recombinant human brain natriuretic peptide in acute left heart failure patients 7 days after onset as well as the effects of plasma MDA and ET-1. Methods: In total, 240 hospitalized patients with acute left heart failure from October 2017 to May 2021 were selected from the Department of Emergency and Critical Care Center of Beijing Anzhen Hospital, Capital Medical University and the Department of Cardiology of the Jilin Provincial People's Hospital. They were randomly divided into routine treatment group and combined treatment group, with 120 cases in each group. The routine treatment group was treated with vasodilation, diuresis, cardiotonic and recombinant human brain natriuretic peptide. The combined treatment group was treated with Qiliqiangxin capsules based on the routine treatment group. One week later, the changes in clinical efficacy, ejection fraction, left ventricular commoid diameter, and plasma BNP, MDA, and ET-1 were compared between the two groups before and after treatment. SPSS 11.5 statistical software was used. The measurement data was expressed in x¯±s, the independent sample t-test was used for comparison between groups, and the paired t-test was used for comparison before and after treatment within groups. Counting data was expressed as case (%), and the rank sum test was used for inter-group comparison. Result: In terms of clinical efficacy, the total effective rate of the combined treatment group was significantly higher than that of the conventional treatment group, and the difference was statistically significant (P<0.05). Compared with the routine treatment group, the left ventricular ejection fraction in the combined treatment group was significantly increased (P<0.05). The levels of plasma BNP, MDA and ET-1 were significantly decreased (P<0.05). Conclusion: Qiliqiangxin capsule combined with rhBNP treatment can effectively improve the clinical symptoms of acute heart failure, as well as reduce the lipid peroxidation product MDA content and endothetin ET-1 level in blood. The clinical application value of the Qiliqiangxin capsule needs to be further confirmed by further trials.


Assuntos
Fármacos Cardiovasculares , Medicamentos de Ervas Chinesas , Insuficiência Cardíaca , Peptídeo Natriurético Encefálico , Humanos , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Peptídeo Natriurético Encefálico/farmacologia , Peptídeo Natriurético Encefálico/uso terapêutico , Volume Sistólico/efeitos dos fármacos , Volume Sistólico/fisiologia , Função Ventricular Esquerda/efeitos dos fármacos , Função Ventricular Esquerda/fisiologia , Cardiotônicos/farmacologia , Cardiotônicos/uso terapêutico , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Fármacos Cardiovasculares/farmacologia , Fármacos Cardiovasculares/uso terapêutico , Quimioterapia Combinada
18.
Zhonghua Nei Ke Za Zhi ; 62(12): 1465-1471, 2023 Dec 01.
Artigo em Zh | MEDLINE | ID: mdl-38044074

RESUMO

Objective: Of all spontaneous bleeding complications in patients with acute ST-elevation myocardial infarction (STEMI), upper gastrointestinal bleeding (UGIB) is the most common and of specific interest, because it can be prevented by several prophylactic measures. The purpose of this study was to investigate the in-hospital incidence, associated outcomes, and predictors of UGIB after STEMI. Methods: In this retrospective study, we analyzed the records of 2 791 patients with acute STEMI admitted to Beijing Anzhen Hospital Affiliated to Capital Medical University between January 2018 and January 2022. The patients were divided into the UGIB group (n=61) and non-UGIB group (n=2 730) according to the presence or absence of upper gastrointestinal hemorrhage, respectively. Baseline clinical conditions, coronary lesions, in-hospital deaths, and in-hospital adverse events were compared between the two groups. Logistic regression analysis was also performed for risk factors that could lead to UGIB. Results: The in-hospital incidence of UGIB after STEMI was 2.2% (61/2 791). Hospital stay was significantly longer in the UGIB group [8(6, 12) days vs. 5 (4, 7) days, Z=3.28, P<0.001] and in-hospital mortality was significantly higher in the UGIB group than in the non-UGIB group (9.8% vs. 0.8%, χ2=0.63, P=0.001). Patients with UGIB were significantly older than those without UGIB (63±11 years vs. 58±11 years, t=-3.75, P<0.001). The serum creatinine level of UGIB patients was significantly higher than that of non-UGIB patients [(80(62, 98) mmol/L vs. 73(64, 84) mmol/L, Z=1.68, P=0.007], the red blood cell count of UGIB patients was significantly lower than that of non-UGIB patients [4.1(3.8, 4.6)×1012/L vs. 4.6(4.2, 4.9)×1012/L, Z=2.61,P<0.001], and the hemoglobin concentration of UGIB patients was significantly lower than that of non-UGIB patients [129(109, 141) g/L vs. 141(130, 152) g/L, Z=2.52,P<0.001]. Brain natriuretic peptide levels were significantly higher in UGIB patients than in non-UGIB patients [331(165, 644) ng/L vs. 181(89, 333) ng/L, Z=2.42,P<0.001]. Logistic regression analysis showed that age (OR=1.045, 95%CI 1.009-1.082, P=0.013); hemoglobin (OR=1.594, 95%CI 1.150-2.210, P=0.005); hematocrit (OR=0.181, 95%CI 0.060-0.546, P=0.002); and mean hemoglobin concentration (OR=0.845, 95%CI 0.752-0.951, P=0.005) were independent risk factors for UGIB in patients with STEMI. Logistic regression analysis of risk factors for in-hospital death revealed that concurrent UGIB was an independent risk factor for in-hospital death in patients with STEMI (OR=2.954, 95%CI 0.635-13.751, P=0.024). Conclusions: The incidence of in-hospital UGIB in STEMI patients was 2.2%, and the in-hospital mortality rate of STEMI complicated with UGIB increased to 9.8%. Concurrent UGIB was an independent risk factor for in-hospital death in patients with STEMI. The most important predictors of in-hospital UGIB in patients with STEMI were age, hemoglobin, hematocrit, and mean hemoglobin concentration.


Assuntos
Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/complicações , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Estudos Retrospectivos , Mortalidade Hospitalar , Medição de Risco , Hemorragia Gastrointestinal/etiologia , Fatores de Risco , Intervenção Coronária Percutânea/efeitos adversos , Arritmias Cardíacas/etiologia , Hemoglobinas , Resultado do Tratamento
19.
Zhonghua Yi Xue Za Zhi ; 103(28): 2163-2167, 2023 Jul 25.
Artigo em Zh | MEDLINE | ID: mdl-37482728

RESUMO

Objective: To explore the rate of Helicobacter pylori (Hp) resistance to levofloxacin and clarithromycin and the common mutation patterns of resistance genes in Ningxia, and to assess the concordance between phenotypic resistance and genotypic resistance. Methods: Cross-sectional study. Patients diagnosed with Hp infection in 14 hospitals in Ningxia region from February 2020 to May 2022 were retrospectively selected. Hp strains were isolated from gastric biopsy specimens of Hp-infected patients and subjected to phenotypic drug sensitivity testing and detection of resistance genes to analyze the rate of Hp resistance to levofloxacin and clarithromycin and the common mutation patterns of resistance genes in Ningxia region; and the concordance rate and Kappa concordance test were used to assess the concordance between phenotypic resistance and genotypic resistance. Results: A total of 1 942 Hp strains were isolated and cultured, and among the infections, 1 069 cases (55.0%) were male and 873 cases (45.0%) were female, aged (50.0±12.5) years (15-86 years). The rates of Hp resistance to levofloxacin and clarithromycin in Ningxia were 42.1% (818/1 942) and 40.1% (779/1 942), respectively, and the rate of dual resistance to both was 22.8% (443/1 942). The rate of resistance to levofloxacin and clarithromycin of Hp strains from female patients was higher than in male patients (levofloxacin: 50.4%(440/873) vs 35.4%(378/1 069); clarithromycin: 44.4%(388/873) vs 36.6%(391/1 069), both P<0.001). Among the GyrA gene mutations associated with levofloxacin resistance, the differences in mutation rate of amino acid at positions 87 and 91 were statistically significant in both drug-resistant and sensitive strains(both P<0.001), except for Asn87Thr. Hp strains were statistically significant for levofloxacin (Kappa=0.834, P<0.001) and clarithromycin (Kappa=0.829, P<0.001) had good concordance in resistance at the phenotypic and genotypic levels. Conclusion: The resistance of Hp to levofloxacin and clarithromycin in Ningxia region is severe, and there is good consistency between genotypic and phenotypic resistance.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Feminino , Humanos , Masculino , Antibacterianos/farmacologia , Claritromicina/farmacologia , Estudos Transversais , Farmacorresistência Bacteriana/genética , Helicobacter pylori/genética , Levofloxacino/farmacologia , Testes de Sensibilidade Microbiana , Estudos Retrospectivos , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais
20.
Zhonghua Yan Ke Za Zhi ; 59(9): 723-729, 2023 Sep 11.
Artigo em Zh | MEDLINE | ID: mdl-37670655

RESUMO

Objective: To evaluate the clinical application value of intraoperative optical coherence tomography (iOCT) in deep anterior lamellar keratoplasty (DALK) using the big-bubble technique to bare Descemet's membrane. Methods: Retrospective case series. Clinical data of 92 patients (92 eyes) with monocular stromal corneal diseases who underwent big-bubble DALK in the Eye Hospital of Shandong First Medical University from January 2020 to August 2021 were collected. There were 53 males and 39 females. The average age was (53.2±16.0) years old. All patients underwent iOCT scanning to determine the location and depth of the injection needle after initial removal of the corneal lesion, to observe the integrity of the recipient bed, Descemet's membrane, after complete lesion removal, and to observe the adhesion between the corneal graft and the recipient bed and check folds on the recipient bed after suturing of the corneal graft. The intraoperative perforation of Descemet's membrane, postoperative thickness of the cornea and the recipient bed, visual acuity, and corneal astigmatism were recorded. Results: By iOCT, the thickness of the recipient bed was found to be about 1/2 of the corneal thickness and relatively uniform in all directions in 62 eyes (67.4%), so the sterile air was injected from the center of the recipient bed to separate it from the stromal layer. In 30 eyes (32.6%) with an uneven thickness of the recipient bed, the sterile air was injected from the paracentral area of the recipient bed. Under the guidance of iOCT scanning, 89 eyes (96.7%) did not experience any perforation of Descemet's membrane during surgery. The Descemet's membrane folds in the central 5-mm area of the recipient bed was observed and flattened in 20 eyes with the assistance of iOCT scanning. The postoperative corneal thickness was (578.95±108.26) µm, and the recipient bed thickness was (36.06±23.11) µm. The best corrected visual acuity of all patients at 6 months after surgery was 0.57±0.25 logMAR, which was significantly better than that before surgery (1.61±1.27 logMAR; P<0.001). The average corneal astigmatism at 6 months after surgery was (2.72±2.44) diopters. Conclusions: The application of iOCT scanning in DALK surgery assisted by the big-bubble method can provide safe guidance for surgeons to adopt correct surgical procedures, decrease the risk of Descemet's membrane perforation, reduce the recipient bed folds, and facilitate corneal interlayer adhesion, thereby improving the visual prognosis.


Assuntos
Astigmatismo , Doenças da Córnea , Transplante de Córnea , Feminino , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Tomografia de Coerência Óptica , Estudos Retrospectivos , Córnea
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