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1.
Zhonghua Wei Chang Wai Ke Za Zhi ; 27(6): 646-652, 2024 Jun 25.
Artículo en Chino | MEDLINE | ID: mdl-38902003

RESUMEN

Peritoneal metastasis is one of the common site of colorectal cancer metastasis and associated with a poor prognosis. The core strategy for colorectal cancer peritoneal metastasis primarily revolves around a comprehensive treatment approach with cytoreductive surgery and systemic chemotherapy as the mainstay, supplemented by intraperitoneal chemotherapy. As an important supplement to treatment, intraperitoneal chemotherapy has broad application prospects. The main modalities are hyperthermic intraperitoneal chemotherapy (HIPEC), neoadjuvant intraperitoneal and systemic chemotherapy (NIPS), early postoperative intraperitoneal chemotherapy (EPIC), sequential postoperative intraperitoneal chemotherapy (SPIC), normothermic intraperitoneal chemotherapy (NIPEC) and pressurized intraperitoneal aerosol chemotherapy (PIPAC). To promote the standardized application of intraperitoneal chemotherapy, further research on the mechanisms underlying peritoneal metastasis of colorectal cancer, selection of effective intraperitoneal chemotherapy agents, determination of optimal timing and administration protocols, exploration of the feasibility of sequential intraperitoneal chemotherapy and conduction of valuable basic and clinical research are currently needed. This paper will review the development and origins of intraperitoneal chemotherapy, treatment modalities, as well as the current application status and prospects of various treatment approaches in the context of peritoneal metastasis of colorectal cancer.


Asunto(s)
Neoplasias Colorrectales , Quimioterapia Intraperitoneal Hipertérmica , Neoplasias Peritoneales , Humanos , Neoplasias Peritoneales/secundario , Neoplasias Peritoneales/tratamiento farmacológico , Neoplasias Peritoneales/terapia , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/tratamiento farmacológico , Procedimientos Quirúrgicos de Citorreducción/métodos , Terapia Combinada , Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico
2.
Zhonghua Wei Chang Wai Ke Za Zhi ; 27(4): 416-423, 2024 Apr 25.
Artículo en Chino | MEDLINE | ID: mdl-38644248

RESUMEN

Neoadjuvant therapy for locally advanced colorectal cancer has made great progress in the past 20 years, but there are still limitations such as side effects, organ dysfunction and unsatisfactory control of metastasis. In recent years, with the improvement of surgical techniques and further development of molecular research, how to further improve local control, reduce distant metastasis, and even avoid surgery according to clinical remission to achieve organ preservation, is the current demand and research goal. With the advancement of molecular research, colorectal cancer has different treatment strategies based on microsatellite status. For patients with microsatellite instability locally advanced colorectal cancer, immune checkpoint inhibitor therapy significantly increased the pathologic complete response rate, reduced the incidence of adverse events and improved organ function compared with conventional chemoradiotherapy. For patients with microsatellite stable locally advanced colon cancer, neoadjuvant therapy is still in the exploratory stage. The standard of care is surgery combined with perioperative chemotherapy. For microsatellite stable locally advanced rectal cancer, the complete response rate is improved by enhancing neoadjuvant therapy, which helps to preserve organs. On the other hand, selective radiotherapy preserves organ function and improves quality of life. This article reviews the neoadjuvant treatment strategies for locally advanced colorectal cancer based on organ-sparing strategies.


Asunto(s)
Neoplasias Colorrectales , Inestabilidad de Microsatélites , Terapia Neoadyuvante , Humanos , Terapia Neoadyuvante/métodos , Neoplasias Colorrectales/terapia , Neoplasias Colorrectales/patología , Calidad de Vida , Inhibidores de Puntos de Control Inmunológico/uso terapéutico
3.
Zhonghua Wai Ke Za Zhi ; 62(2): 162-166, 2024 Feb 01.
Artículo en Chino | MEDLINE | ID: mdl-38310385

RESUMEN

Objective: To preliminarily examine the feasibility and outcome of single-port laparoscopic radical prostatectomy with full-length urethral preservation (FLUP-SPRP). Method: This study was a prospective case series study. A total of 25 patients with prostate cancer who met the enrollment criteria and agreed to this surgical procedure from March 2022 to December 2022 were collected at the Department of Urology, the Second Affiliated Hospital of Nanjing Medical University. The age of the patients was (67.2±7.6) years (range: 61 to 76 years). This novel procedure was performed by an experienced surgeon who performed single hole radical prostatectomy skillfully. Patient urinary control, tumor control, and related surgical complications after surgery were regularly monitored. Postoperative urinary control was evaluated using the daily amount of urine pad, 0 to 1 piece of urine pad was to restore urinary control, and 0 to 1 piece of pad within 24 hours after catheter removal was immediate urinary control. Result: All prodecures were successfully completed without transit to open surgery. The surgical time was (128.4±22.4) minutes (range: 100 to 145 minutes), the intraoperative blood loss was (68.2±13.7) ml (range: 50 to 120 ml). The urethral injury occurred in 4 cases during surgery and was repaired by sutures. The urinary control recovery rates within 24 hours, 1 week, 4 weeks, and 7 weeks after surgery were 80.0%, 84.0%, 92.0% and 100%, respectively. Postoperative large section pathology revealed 1 case with a positive basal margin of the prostate and negative margins of all prostate glands around the urethra. Postoperative complications included urinary tract infection in 3 cases, urodynia in 2 cases, and acute urinary retention in 1 case. MRI follow-up 3 months after surgery showed normal anatomy of the bladder and urethra. The follow-up values of prostate specific antigen at 3 and 6 months after surgery were less than 0.1 µg/L. Conclusions: The preliminary results of this study indicate that the FLUP-SPRP procedure is safe and feasible. The early results of postoperative urinary control and oncology are as expected.


Asunto(s)
Laparoscopía , Neoplasias de la Próstata , Masculino , Humanos , Persona de Mediana Edad , Anciano , Uretra/cirugía , Uretra/patología , Vejiga Urinaria , Neoplasias de la Próstata/cirugía , Neoplasias de la Próstata/patología , Anastomosis Quirúrgica/métodos , Prostatectomía/métodos , Laparoscopía/métodos
4.
Phys Rev Lett ; 127(3): 031102, 2021 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-34328784

RESUMEN

We report observations of gamma-ray emissions with energies in the 100-TeV energy region from the Cygnus region in our Galaxy. Two sources are significantly detected in the directions of the Cygnus OB1 and OB2 associations. Based on their positional coincidences, we associate one with a pulsar PSR J2032+4127 and the other mainly with a pulsar wind nebula PWN G75.2+0.1, with the pulsar moving away from its original birthplace situated around the centroid of the observed gamma-ray emission. This work would stimulate further studies of particle acceleration mechanisms at these gamma-ray sources.

5.
Zhonghua Xin Xue Guan Bing Za Zhi ; 49(5): 467-473, 2021 May 24.
Artículo en Chino | MEDLINE | ID: mdl-34034380

RESUMEN

Objective: To investigate the feasibility, efficacy and safety of transbrachial access for interventional therapy on prosthetic paravalvular leak (PVL) post surgical valve replacement. Methods: This is a retrospective study. Patients with PVL after surgical valve replacement who underwent interventional therapy via the brachial artery approach in Structural heart disease center of Fuwai hospital between August 2017 and October 2019, were included. All patients underwent puncture of the brachial artery under local anesthesia, angiography and transcatheter closure procedure were performed. The procedure was performed under transthoracic echocardiography (TTE) guidance. Baseline data, operation data and pre-and post-operative TTE examination results were collected and analyzed. Postoperative complications were recorded and operational adverse events were obtained during follow up in the outpatient department after discharge. The operation success rate was calculated, which was defined as the degree of perivalvular regurgitation decrease by 1 grade and above according to TTE without interfering the valve movement and coronary artery blood flow within 30 days after occluder placement. Results: A total of 10 patients were enrolled in this study, the mean age was (57.5±14.6) years, and 6 patients were males. There were 7 cases with aortic PVL, and 3 cases with mitral PVL. Except for one patient who was converted to the femoral vein-transseptal approach, the other 9 patients were successfully implanted with the devices via the brachial artery approach. The operation time was (103.3±34.0) minutes, and there was no need for rigorous bed rest after the operation. The median hospital stay was 7.5 (3.0, 9.8) days. The operation success rate was 9/10 via the brachial artery approach. The differences in the degree of perivalvular regurgitation, New York Heart Association (NYHA) classification, left ventricular end diastolic diameter and left atrial diameter before and after operation were statistically significant (all P<0.05). One case developed new hemolysis with renal insufficiency on the second day after procedure and discharged after successful dialysis. Another case experienced complication of brachial artery pseudoaneurysm after procedure and discharged after successful treatment with thrombin injection. The mean follow-up time was (14.3±7.9) months. During the follow-up, NYHA classification remained as Ⅰ/Ⅱ in 9 patients, no operational adverse events were observed. Conclusions: Transbrachial access for interventional therapy on PVL post surgical valve replacement is a feasible, effective, and safe procedure. It has the advantages of simplifying the operation process and reducing postoperative bed rest time.


Asunto(s)
Implantación de Prótesis de Válvulas Cardíacas , Prótesis Valvulares Cardíacas , Adulto , Anciano , Válvula Aórtica/cirugía , Cateterismo Cardíaco , Estudios de Factibilidad , Femenino , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Instrumentos Quirúrgicos , Resultado del Tratamiento
6.
Phys Rev Lett ; 126(14): 141101, 2021 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-33891464

RESUMEN

We report, for the first time, the long-awaited detection of diffuse gamma rays with energies between 100 TeV and 1 PeV in the Galactic disk. Particularly, all gamma rays above 398 TeV are observed apart from known TeV gamma-ray sources and compatible with expectations from the hadronic emission scenario in which gamma rays originate from the decay of π^{0}'s produced through the interaction of protons with the interstellar medium in the Galaxy. This is strong evidence that cosmic rays are accelerated beyond PeV energies in our Galaxy and spread over the Galactic disk.

7.
Zhonghua Wei Chang Wai Ke Za Zhi ; 22(12): 1159-1164, 2019 Dec 25.
Artículo en Chino | MEDLINE | ID: mdl-31874532

RESUMEN

Objective: To explore the effect of enterostomy on analgesic pattern in advanced digestive tract cancer. Methods: A retrospective cohort study was carried out, which was approved by the Ethics Committee of the Sixth Affiliated Hospital of Sun Yat-sen University (E2018026). Inclusion criteria were as follows: (1)age and gender were not limited; (2) all the gastrointestinal malignancies were confirmed histologically, and local recurrence or metastasis were confirmed by CT or MR; (3) numerical rating scale (NRS) ≥4 points, opioid analgesic drugs were required; (4) informed consents were signed by patients of their own. Exclusion criteria were as follows: (1) malignancies of early stage; (2) suspicious adverse mental states which might lead to poor administration compliance; (3) hypersensitivity or allergic reactions to opioids. Clinical data of patients with advanced gastrointestinal cancer receiving comprehensive treatment at the Medical Oncology Department of the Sixth Affiliated Hospital of Sun Yat-sen University from September 2016 to April 2017 were retrospectively collected. The patients were divided into the stoma group and the non-stoma group. The clinical findings of two groups were analyzed, including age, sex, ostomy status, pain location, presence or absence of intestinal obstruction, pain characteristics, selection of opioid analgesic agents, treatment of side effects of analgesics. Pain was assessed using brief pain inventory(BPI) table and NRS score. Strong opioids were prescribed for patients of NRS ≥4. Patients who were intolerant to opioids required opioid titration. The titration drugs included oral or IV morphine and oxycodone. After achievement of adequate pain control, long-acting opioids were administered, which included sustained-release morphine tablets, controlled release oxycodone and transdermal fentanyl. Criteria for pain relief included NRS≤3, breakthrough pain <3 times/day and duration of adequate pain control >3 days. The χ(2) test and the Wilcoxon signed rank sum test (nonparametric test) were used to analyze the clinical features of patients in the stoma and non-stomach groups. In order to find the factors associated with maintenance therapy and the use of laxatives, the variables were compared as well as in multivariate analysis with multiple regression models. For all the statistical tests, a value of P<0.05 in a two-tailed test was established as the alpha significance level. Result: A total of 123 patients were enrolled in this study, including 79 males (64.2%) and 44 females (35.8%) with a median age of 51 years. Fifty-two patients were in stoma group, including 30 (24.4%) of ileostomy and 22 (17.9%) of colostomy, and 71 patients were in non-stoma group. Pain of 40 (76.9%) patients in stoma group located in abdomenopelvic site while the pain of 44 (62.0%) patients in non-stoma group located in other sites. Compared with non-stoma group, cases in stoma group complained more abdominopelvic pain (73% vs. 62.0%, P<0.001).The median NRS pain score before treatment in the stoma group and the non-stoma group was 5.7 and 5.6, respectively, without statistically significant difference (P=0.741). After analgesic management, the above scores reduced to 2.1 and 2.3, respectively, without statistically significant difference as well (P=0.092). Analgesic treatment was effective in 111 cases (90.2%), including 49 cases (94.2%) in the stoma group, and 62 cases (87.3%) in the non-stoma group, and there was no statistically significant difference between the two groups (P=0.202). There was more application of fentanyl transdermal patch [34.6%(18/52) vs. 9.8%(7/71)] in the stoma group, while more application of lactulose laxative [78.9%(56/71) vs. 61.5%(32/52)](χ(2)=10.023, P=0.002) in the non-stoma group. Multivariate analysis revealed that ostomy (OR=0.290, 95%CI: 0.102-0.824, P=0.009) and pain site (OR=5.691, 95%CI:1.709-18.948, P=0.005) were independent factors affecting the choice of the first line opioid sustained release agent. Of the 123 patients with maintaining analgesia, 98 had available data of laxative use, of whom 46 used laxatives to prevent or treat constipation, and the proportion of laxatives in stoma group (21.2%, 11/52) was significantly lower than that in non-stoma group (49.3%, 35/71) (χ(2)=6.957, P=0.008). Multivariate analysis of the application of laxative use showed that age (OR=0.281, 95% CI: 0.123-0.684, P=0.010) and ostomy (OR=2.621, 95% CI: 1.033-6.687, P=0.045) were independent factors affecting the use of lactulose laxatives. Conclusions: Enterostomy may affect the analgesic pattern in advanced digestive tract cancer. Patients with stoma are more likely to use fentanyl transdermal patches and younger patients with stoma do not need prophylactic use of laxatives.


Asunto(s)
Analgésicos/uso terapéutico , Enterostomía , Neoplasias Gastrointestinales/complicaciones , Dolor/tratamiento farmacológico , Analgésicos/administración & dosificación , Femenino , Neoplasias Gastrointestinales/terapia , Humanos , Masculino , Persona de Mediana Edad , Dolor/etiología , Estudios Retrospectivos
8.
Phys Rev Lett ; 123(5): 051101, 2019 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-31491288

RESUMEN

We report on the highest energy photons from the Crab Nebula observed by the Tibet air shower array with the underground water-Cherenkov-type muon detector array. Based on the criterion of a muon number measured in an air shower, we successfully suppress 99.92% of the cosmic-ray background events with energies E>100 TeV. As a result, we observed 24 photonlike events with E>100 TeV against 5.5 background events, which corresponds to a 5.6σ statistical significance. This is the first detection of photons with E>100 TeV from an astrophysical source.

9.
Epilepsy Res ; 152: 67-72, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30909054

RESUMEN

NG2 cells are oligodendrocyte progenitor cells, and have been shown to receive synaptic input from pyramidal neurons to generate action potentials. Whether any change of these cells occurs after status epilepticus (SE) and subsequent temporal lobe epilepsy remains unknown. In the present study, the expression of NG2 was investigated in the mouse hippocampus after pilocarpine-induced status epilepticus (PISE). We showed that reactive NG2 cells were significantly increased from 1 day to 2 months after PISE. Double immunofluorescence indicated that few NG2 cells differentiated into neurons and astrocytes after PISE, whereas the number of NG2 cells was increased significantly in the stratum lucidum of CA3 area from 1 day onwards after PISE. Our results suggest that the significantly increased reactive NG2 cells from acute to chronic stage after PISE may be involved in epileptogenesis.


Asunto(s)
Antígenos/metabolismo , Proliferación Celular/fisiología , Epilepsia/inducido químicamente , Epilepsia/patología , Hipocampo/patología , Células Precursoras de Oligodendrocitos/patología , Proteoglicanos/metabolismo , Animales , Antígeno CD11b/metabolismo , Calbindina 2/metabolismo , Calbindinas/metabolismo , Proliferación Celular/efectos de los fármacos , Proteína Ácida Fibrilar de la Glía/metabolismo , Masculino , Ratones , Agonistas Muscarínicos/toxicidad , Células Precursoras de Oligodendrocitos/efectos de los fármacos , Células Precursoras de Oligodendrocitos/metabolismo , Pilocarpina/toxicidad , Factores de Tiempo
10.
Eur Rev Med Pharmacol Sci ; 22(7): 1987-1993, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29687853

RESUMEN

OBJECTIVE: To investigate the biological role and clinical significance of long non-coding RNAs (lncRNA) LINC01116 in breast cancer. MATERIALS AND METHODS: In the public database Gene Expression Omnibus (GEO), the breast cancer data set GSE54002 was screened for differentially expressed lncRNA LINC01116 in breast cancer tissues and paracancerous tissues. Quantitative Real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of LINC01116 in 64 breast cancer tissues and 30 normal breast tissues. Level of LINC01116 and clinicopathological parameters of breast cancer were statistically analyzed. The effect of LINC01116 in breast cancer cells was investigated after knockdown of LINC01116. Luciferase reporter gene was further used to investigate the mechanism of endogenous RNA (ceRNA). RESULTS: Results of GSE54002 showed that the expression of LINC01116 in breast cancer tissues was significantly increased. In clinical samples, the level of LINC01116 in patients with breast cancer was significantly increased, which was correlated with the overall survival, tumor size and tumor node metastasis (TNM) stage in patients, but not correlated with the age, sex and lymph node metastasis (p>0.05). LINC01116 can act as an endogenous sponge and bind directly to miR-145, resulting in the up-regulation of estrogen receptor 1 (ESR1), a target gene of miR-145. CONCLUSIONS: LncRNA LINC01116 is highly expressed in breast cancer and is a new prognostic biomarker in breast cancer. Our study establishes a new link between LINC01116, miR-145 and ESR1.


Asunto(s)
Neoplasias de la Mama/patología , Receptor alfa de Estrógeno/genética , Regulación Neoplásica de la Expresión Génica , MicroARNs/fisiología , ARN Largo no Codificante/fisiología , Adulto , Anciano , Neoplasias de la Mama/genética , Neoplasias de la Mama/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad
11.
Phys Rev Lett ; 120(3): 031101, 2018 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-29400499

RESUMEN

We analyze the Sun's shadow observed with the Tibet-III air shower array and find that the shadow's center deviates northward (southward) from the optical solar disk center in the "away" ("toward") interplanetary magnetic field (IMF) sector. By comparing with numerical simulations based on the solar magnetic field model, we find that the average IMF strength in the away (toward) sector is 1.54±0.21_{stat}±0.20_{syst} (1.62±0.15_{stat}±0.22_{syst}) times larger than the model prediction. These demonstrate that the observed Sun's shadow is a useful tool for the quantitative evaluation of the average solar magnetic field.

13.
Eur J Clin Microbiol Infect Dis ; 35(3): 353-61, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26796551

RESUMEN

To detect Salmonella more efficiently and isolate strains more easily, a novel and simple detection method that uses an enrichment assay and two chromogenic reactions on a chromatography membrane was developed. Grade 3 chromatography paper is used as functionalized solid phase support (SPS), which contains specially optimized medium. One reaction for screening is based on the sulfate-reducing capacity of Salmonella. Hydrogen sulfide (H2S) generated by Salmonella reacts with ammonium ferric citrate to produce black colored ferrous sulfide. Another reaction is based on Salmonella C8 esterase that is unique for Enterobacteriaceae except Serratia and interacts with 4-methylumbelliferyl caprylate (MUCAP) to produce fluorescent umbelliferone, which is visible under ultraviolet light. A very low detection limit (10(1) CFU ml(-1)) for Salmonella was achieved on the background of 10(5) CFU ml(-1) Escherichia coli. More importantly, testing with more than 1,000 anal samples indicated that our method has a high positive detection rate and is relatively low cost, compared with the traditional culture-based method. It took only 1 day for the preliminary screening and 2 days to efficiently isolate the Salmonella cells, indicating that the new assay is specific, rapid, and simple for Salmonella detection. In contrast to the traditional culture-based method, this method can be easily used to screen and isolate targeted strains with the naked eye. The results of quantitative and comparative experiments showed that the visual detection technique is an efficient alternative method for the screening of Salmonella spp. in many applications of large-sized samples related to public health surveillance.


Asunto(s)
Técnicas Bacteriológicas , Cromatografía en Papel/métodos , Salmonella/aislamiento & purificación , Humanos , Sulfuro de Hidrógeno/metabolismo , Himecromona/análogos & derivados , Himecromona/química , Salmonella/clasificación , Salmonella/metabolismo , Infecciones por Salmonella/diagnóstico , Infecciones por Salmonella/microbiología , Sensibilidad y Especificidad
14.
Arch Pediatr ; 21(2): 162-9, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24388336

RESUMEN

UNLABELLED: Septicemia is a common cause of morbidity and mortality among newborns in the developing world. However, accurate clinical diagnosis of neonatal sepsis is often difficult because symptoms and signs are often nonspecific. Blood culture has been the gold standard for confirmation of the diagnosis. However, the sensitivity is low and results are usually not promptly obtained. Therefore, the diagnosis of sepsis is often based on clinical signs in association with laboratory tests such as platelets count, immature/total neutrophils ratio (I/T), and a rise in C-reactive protein (CRP). Polymerase chain reaction (PCR) methods for the detection of neonatal sepsis represent new diagnostic tools for the early identification of pathogens. METHODS: During a 4-month prospective study, 16S rRNA PCR was compared with conventional blood culture for the diagnosis of neonatal bacterial sepsis. In addition, the relationship between known risk factors, clinical signs, laboratory parameters, and the diagnosis of sepsis was considered. RESULTS: Sepsis was suspected in 706 infants from the intensive neonatal care unit. They all were included in the study. The number of positive cultures and positive PCR results were 95 (13.5%) and 123 (17.4%), respectively. Compared with blood culture, the diagnosis of bacterial sepsis by PCR revealed a 100.0% sensitivity, 95.4% specificity, 77.2% positive predictive value, and 100.0% negative predictive value. In this study, Apgar scores at 5 min, weight, icterus, irritability, feeding difficulties, gestational age (GA), premature rupture of membrane (PRM), platelets count, I/T, and a marked rise in CRP were important in establishing the diagnosis of sepsis in the newborn. In addition, weight, GA, PRM, irritability, duration of antibiotic usage, mortality rate, and number of purulent meningitis cases were significantly different between early-onset sepsis and late-onset sepsis. CONCLUSION: 16S rRNA PCR increased the sensitivity in detecting bacterial DNA in newborns with signs of sepsis, allowed a rapid detection of the pathogens, and led to shorter antibiotic courses. However, uncertainty about the bacterial cause of sepsis was not reduced by this method. 16S rRNA PCR needs to be further developed and improved. Blood culture is currently irreplaceable, since pure isolates are essential for antimicrobial drug susceptibility testing.


Asunto(s)
Infecciones Bacterianas/diagnóstico , Infecciones Bacterianas/genética , Técnicas Bacteriológicas , Sangre/microbiología , Países en Desarrollo , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética , Sepsis/diagnóstico , Sepsis/genética , Infecciones Bacterianas/mortalidad , China , Medios de Cultivo , Femenino , Humanos , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Masculino , Valor Predictivo de las Pruebas , Estudios Prospectivos , Factores de Riesgo , Sepsis/mortalidad , Tasa de Supervivencia , Centros de Atención Terciaria
15.
Phys Rev Lett ; 111(1): 011101, 2013 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-24027782

RESUMEN

We report on a clear solar-cycle variation of the Sun's shadow in the 10 TeV cosmic-ray flux observed by the Tibet air shower array during a full solar cycle from 1996 to 2009. In order to clarify the physical implications of the observed solar cycle variation, we develop numerical simulations of the Sun's shadow, using the potential field source surface model and the current sheet source surface (CSSS) model for the coronal magnetic field. We find that the intensity deficit in the simulated Sun's shadow is very sensitive to the coronal magnetic field structure, and the observed variation of the Sun's shadow is better reproduced by the CSSS model. This is the first successful attempt to evaluate the coronal magnetic field models by using the Sun's shadow observed in the TeV cosmic-ray flux.

16.
Sci Rep ; 3: 1086, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23336068

RESUMEN

The complex structural transformation in crystals under static pressure or shock loading has been a subject of long-standing interest to materials scientists and physicists. The polymorphic transformation is of particular importance for iron (Fe), due to its technological and sociological significance in the development of human civilization, as well as its prominent presence in the earth's core. The martensitic transformation α→ε (bcc→hcp) in iron under shock-loading, due to its reversible and transient nature, requires non-trivial detective work to uncover its occurrence. Here we reveal refined microstructural fingerprints, needle-like colonies and three sets of {112}<111> twins with a threefold symmetry, with tell-tale features that are indicative of two sequential martensitic transformations in the reversible α→ε phase transition, even though no ε is retained in the post-shock samples. The signature orientation relationships are consistent with previously-proposed transformation mechanisms, and the unique microstructural fingerprints enable a quantitative assessment of the volume fraction transformed.


Asunto(s)
Hierro/química , Modelos Químicos , Modelos Moleculares , Transición de Fase , Simulación por Computador , Cristalografía por Rayos X , Humanos , Microscopía Electrónica de Transmisión , Presión
17.
Science ; 314(5798): 439-43, 2006 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-17053141

RESUMEN

The intensity of Galactic cosmic rays is nearly isotropic because of the influence of magnetic fields in the Milky Way. Here, we present two-dimensional high-precision anisotropy measurement for energies from a few to several hundred teraelectronvolts (TeV), using the large data sample of the Tibet Air Shower Arrays. Besides revealing finer details of the known anisotropies, a new component of Galactic cosmic ray anisotropy in sidereal time is uncovered around the Cygnus region direction. For cosmic-ray energies up to a few hundred TeV, all components of anisotropies fade away, showing a corotation of Galactic cosmic rays with the local Galactic magnetic environment. These results have broad implications for a comprehensive understanding of cosmic rays, supernovae, magnetic fields, and heliospheric and Galactic dynamic environments.

18.
Phys Rev Lett ; 93(6): 061101, 2004 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-15323615

RESUMEN

We report on the solar diurnal variation of the galactic cosmic-ray intensity observed by the Tibet III air shower array during the period from 1999 to 2003. In the higher-energy event samples (12 and 6.2 TeV), the variations are fairly consistent with the Compton-Getting anisotropy due to the terrestrial orbital motion around the Sun, while the variation in the lower-energy event sample (4.0 TeV) is inconsistent with this anisotropy. This suggests an additional anisotropy superposed at the multi-TeV energies, e.g., the solar modulation effect. This is the highest-precision measurement of the Compton-Getting anisotropy ever made.

19.
Zhongguo Yi Liao Qi Xie Za Zhi ; 24(5): 249-53, 282, 2000 Sep.
Artículo en Chino | MEDLINE | ID: mdl-12583016

RESUMEN

It is inevitable for our country to take the concept of informationized hospital in order to improve diagnosis quality and reduce administrative overhead. However we can not follow the way that has been taken in developed countries because of the national conditions of China. So we have to take some effective strategies to implement our high performance PACS. Based on our concrete experience gained from the development of a PACS in Shanghai, this paper presents a distributed architecture of PACS and describes the design detail of several PACS core components.


Asunto(s)
Sistemas de Computación , Sistemas de Información Radiológica , Programas Informáticos , Redes de Comunicación de Computadores , Diseño de Equipo , Sistemas de Información en Hospital , Sistemas de Información Radiológica/instrumentación , Diseño de Software
20.
J Chromatogr B Biomed Sci Appl ; 696(1): 166-71, 1997 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-9300922

RESUMEN

A simple and sensitive method for the analysis of ivermectin (22,23-dihydroavermectin B1) in swine liver based on immunoaffinity column cleanup is described. The immunosorbent was prepared by coupling polyclonal anti-ivermectin antibodies to carbonyl diimidazole-activated Sepharose CL-4B. After extraction with methanol, ivermectin was cleaned up on an immunoaffinity column, and determined by reversed-phase liquid chromatography with UV absorbance detection at 245 nm. Recoveries of ivermectin from fortified samples of 5-10 micrograms kg-1 levels ranged 85-102%, with coefficients of variation of 6-12%. The limit of detection was 2 micrograms kg-1 in a 5-g samples.


Asunto(s)
Antiparasitarios/análisis , Cromatografía de Afinidad/métodos , Residuos de Medicamentos/análisis , Ivermectina/análisis , Hígado/química , Animales , Antiparasitarios/química , Antiparasitarios/inmunología , Residuos de Medicamentos/química , Sueros Inmunes/química , Sueros Inmunes/inmunología , Inmunoadsorbentes/química , Inmunoadsorbentes/inmunología , Ivermectina/química , Ivermectina/inmunología , Conejos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrofotometría Ultravioleta , Porcinos
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