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1.
Artículo en Chino | MEDLINE | ID: mdl-37524683

RESUMEN

Objective: To investigate the clinical characteristics of patients with acute phosphine poisoning, and to follow up and evaluate the prognosis of patients. Methods: In May 2022, 12 patients with phosphine poisoning by respiratory inhalation in Beijing Chao-Yang Hospital of Capital Medical University were analyzed. The patients were treated with symptomatic support therapy. Three months later, patients were re-evaluated the symptoms of poisoning, pulmonary function and magnetic resonance imaging (MRI) of the brain to understand the prognosis of the phosphine poisoning. Results: The main symptoms of 12 patients were respiratory and central nervous system symptoms with hypoxia. The symptoms of poisoning improved after treatment. Follow-up found that the patients had different degrees of residual symptoms. Pulmonary function showed increased airway resistance. Airway challenge test was positive in some patients. MRI of the head of some patients showed small ischemic focus in bilateral frontal lobes. Conclusion: Acute phosphine poisoning may cause persistent damage to the respiratory system and central system, and residual symptoms after 3 months.


Asunto(s)
Enfermedades del Sistema Nervioso Central , Fosfinas , Intoxicación , Enfermedades Respiratorias , Humanos , Estudios de Seguimiento , Pulmón , Fosfinas/envenenamiento , Intoxicación/diagnóstico , Enfermedades del Sistema Nervioso Central/inducido químicamente , Enfermedades Respiratorias/inducido químicamente
2.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 57(7): 694-700, 2022 Jul 02.
Artículo en Chino | MEDLINE | ID: mdl-35790508

RESUMEN

Objective: To investigate the morphological characteristics of coracoid process in different stages of temporomandibular joint osteoarthrosis (TMJOA), and to provide theoretical data for clinical and anatomic study. Methods: A total of 290 patients who were diagnosed with TMJOA in the Department of Temporomandibular Joint, Kunming Medical University School and Hospital of Stomatology from January 2015 to February 2021 were collected, including 69 males and 221 females, with an average age of 35.1±13.7 years (16-69 years old), 64 cases of unilateral lesions (64 sides), and 226 cases of bilateral lesions (452 sides). According to the TMJOA X-ray staging standard put forward by Ma Xuchen in 2005, the affected joints were divided into stage I (227 sides), stage Ⅱ (38 sides), stage Ⅲ (164 sides) and stage Ⅳ (87 sides). Twenty-six patients without clinical and imaging manifestations of temporomandibular disorders in the Department of Radiology, Kunming Medical University School and Hospital of Stomatology from October 2020 to June 2021 were selected as the control group, including 8 males and 18 females. The average age was (34.3±13.9) years (17-60 years). The dicom data of each group were imported into SimplantPro11.04 software to measure the height of coracoid process, anteversion angle and the ratio of coracoid vertex to mandibular corner to condylar vertex to mandibular angle. R 3.6.1 was used to analyze the difference of the morphological characteristics of coracoid process between in the affected side of TMJOA and in the both sides of the control group, in the healthy side and the affected side of unilateral patients and in different stages of TMJOA. Results: The height of the coracoid process [(16.26±2.81 mm)], the ratio of the coracoid process vertex-mandibular angle point and the condyle vertex-mandibular angle point distance [0.96(0.92,1.01)] on the affected side of TMJOA were significantly higher than those in the control group [(15.31±3.03)mm;0.95(0.89、0.99)] (t=2.18, P=0.033; t=2.87, P=0.004). There was no significant difference between the ante-version angle and the control group (t=-1.37, P=0.176). The ratio of the distance between the apex of the coracoid process and the apex of the mandibular angle to the apex of the condyle and the angle of the mandible in the affected side of unilateral patients was significantly greater than that in the healthy side (t=-3.46, P=0.001). There was no significant difference in coracoid height, coracoid anteversion angle and the healthy side (t=-1.85, P=0.069; t=-0.06, P=0.955) in different periods. The intra-group analysis showed that there was no significant difference in the height of the coracoid process in different stages (F=0.37, P=0.774). There was no significant difference in the ante-version angle of the coracoid process: stage I, stage Ⅱ, and stage Ⅲ (P>0.008), but all were significantly smaller than stage Ⅳ (PⅠ-Ⅳ<0.001, PⅡ-Ⅳ=0.009, PⅢ-Ⅳ<0.001). The ratio of the distance between coracoid apex-mandibular angle and condyle apex-mandibular angle: there was no significant difference in stage I, stage Ⅱ, and stage Ⅲ (P>0.008), and stage I and stage Ⅲ were significantly smaller than stage Ⅳ (P<0.001). Conclusions: The coracoid height and the ratio of the coracoid apex-mandibular angle to the condyle apex-mandibular angle distance on the TMJOA side were significantly greater than those without temporomandibular joint disorders. The bone deposition was mainly concentrated in the upper and posterior part of the condyle. TMJOA had a certain correlation with the height of the coracoid process.

3.
Zhonghua Gan Zang Bing Za Zhi ; 29(9): 855-860, 2021 Sep 20.
Artículo en Chino | MEDLINE | ID: mdl-34638204

RESUMEN

Objective: To analyze the clinical value and predictive difference of serum Golgi protein 73 (GP73) and serum autophagy-related protein p62 levels in the short-term prognosis of patients with hepatitis B virus-related acute-on-chronic liver failure (ACLF). Methods: Clinical data of admitted cases to our hospital from October 2018 to April 2020 were retrospectively analyzed. Simultaneously, there were 32 cases with HBV-related ACLF in group A, 65 cases with hepatitis B virus-related cirrhosis in group B and C (Child-Pugh Class A, 34 cases as B group, and Child-Pugh B/C class, 31 cases as group C), and another 30 healthy subjects served as the control group (group D). The serum GP73 and p62 levels of the four selected groups were measured. ACLF group patients were followed up for 3 months to analyze the prognosis of the patients. The serum GP73 and p62 levels of patients who died and survived during hospitalization were compared. The data were analyzed by one-way analysis of variance, independent sample t-test, and Pearson's correlation analysis. Receiver operating characteristic curve (ROC) was used to analyze the predictive value of GP73 and p62 levels in surviving patients. Results: GP73 levels in the four groups A, B, C and D were (284.30 ± 70.55) ng/ml, (125.33 ± 20.57) ng/ml, (159.82 ± 31.20) ng/ml, and (45.46 ± 10.22) ng/ml, respectively. The p62 levels were (1.30 ± 0.35) ng/ml, (2.88 ± 0.58) ng/ml, (2.02 ± 0.545) ng/ml, and (4.68 ± 1.03) ng/ml, respectively. GP73 detection value was significantly higher in group A than the other three groups (P < 0.05). Group D had significantly lower value than the other three groups (P < 0.05), and group C had significantly higher value than group B (P < 0.05). The detection value of p62 in group A was significantly lower than the other three groups (P < 0.05). Group D had significantly higher value than the other three groups (P < 0.05), and group B had slightly higher value than group C, and the differences were statistically significant (P < 0.05). There was a negative correlation between GP73 and p62 (r = -0.695, P < 0.001). Survived patients GP73 level in the ACLF group was significantly lower than dead patients [(212.17 ± 22.47) ng/ml and (340.08 ± 32.91) ng/ml, t = 12.493, P < 0.05], and p62 level was significantly higher than dead patients [(1.46 ± 0.28) ng/ml and (1.18 ± 0.35) ng/ml, t = 2.445, P < 0.05]. According to the ROC curve analysis results, the area under the curve (AUC) of GP73 was 0.865, the AUC of p62 was 0.750, and the combined AUC of the both was 0.968. Conclusion: Both GP73 and p62 have a certain predictive value for the short-term prognosis of HBV-related ACLF patients, but the combination of the two indicators has a higher predictive value.


Asunto(s)
Insuficiencia Hepática Crónica Agudizada , Carcinoma Hepatocelular , Neoplasias Hepáticas , Insuficiencia Hepática Crónica Agudizada/diagnóstico , Virus de la Hepatitis B , Humanos , Proteínas de la Membrana , Pronóstico , Estudios Retrospectivos
5.
Zhonghua Er Ke Za Zhi ; 58(9): 758-763, 2020 Sep 02.
Artículo en Chino | MEDLINE | ID: mdl-32872717

RESUMEN

Objective: To analyse the long-term efficacy in childhood T-cell acute lymphoblastic leukemia (T-ALL) cases enrolled in the national protocol of childhood leukemia in China-acute lymphoblastic leukemia (NPCLC-ALL) 2008. Methods: Clinical data of 96 patients diagnosed as T-ALL and treated with NPCLC-ALL2008 protocol between January 2009 and December 2017 in the Department of Hematology-Oncology, the Children's Hospital, Zhejiang University School of Medicine were analyzed retrospectively. Predictive value of minimal residual disease (MRD) monitored by flow cytometry was analyzed. Kaplan-Meier method was used for long-term survival analysis. Results: A total of 96 evaluable patients with newly diagnosed T-ALL were analysed, including 72 males and 24 females. The age was 9.5 (ranged from 1.0 to 16.0) years. The follow-up time was 5.7 (ranged from 1.0 to 9.7) years. Among 96 patients, 92 (96%) achieved complete remission. The 5-year event free survival (EFS) and overall survival (OS) rates were (61±6) % and (70±5) %, respectively. Relapse occurred in 18 cases and the 5-year cumulative incidence of relapse was (27±6) %. Twenty-four patients died. The 5-year OS rates of patients with MRD>5% on day 15 of induction therapy was significantly worse than those with MRD≤5% ((60±12) % vs. (72±6) %, χ(2)=3.904, P=0.048) . The 5-year EFS and OS rates were obviously lower in patients with MRD>10% before the consolidation therapy ((50±35) %). The 5-year OS rates of patients with relapsed disease was significantly worse than those without ((26±13) % vs. (81±5) %, χ(2)=18.411, P<0.01). The earlier the relapse, the worse the prognosis. The 5-year OS rates for patients relapsed within 6 months, within 3 years and more than 3 years, were (25±22) %, (30±14) % and (50±35) % respectively (χ(2)=13.207, P<0.01). Conclusions: NPCLC-ALL2008 protocol is effective for childhood T-ALL. The MRD guided accurate risk stratification and individualized treatment can reduce the relapse and improve the survival rate of pediatric T-ALL.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Leucemia-Linfoma Linfoblástico de Células Precursoras , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Niño , China , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Neoplasia Residual , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamiento farmacológico , Pronóstico , Estudios Retrospectivos , Linfocitos T , Resultado del Tratamiento
6.
Poult Sci ; 99(7): 3445-3451, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32616238

RESUMEN

This study was conducted to determine the effect of Moringa oleifera stem (MOS) meal in ducks. A total of 225 ducklings at 1 D of age were randomly assigned to 3 dietary treatment groups with 3 replicates of 25 each. The growth experiment lasted 63 D . The egg experiment started from 23 to 27 wk of age. Ducks were randomly divided into 3 treatment groups with 3 replications of 15 each. The following dietary treatments were applied: 1) Control (CON), basal diet + 0% MOS meal; 2) basal diet + 2% MOS meal; 3) basal diet + 4% MOS meal. During 0 to 4 wk of age, ducks fed 2% MOS diet showed significantly increase in average daily feed intake (ADFI) and average daily gain (ADG; P < 0.05) and ducks fed 4% MOS diet had a significant improvement in feed conversion rate (FCR; P < 0.05). However, ADFI, ADG, and FCR were not affected significantly during 5 to 9 wk of age (P > 0.05). In egg production experiment, ADFI, average egg weight, laying rate, and FCR showed significant increase in 4% MOS diets (P < 0.05). Laying ducks fed 4% MOS diet had a higher egg shape index, whereas a lower yolk color compared with CON (P < 0.05). The proportion of broken shell eggs were zero in experimental diets, whereas 3% of which occurred in CON (P < 0.05). However, no significant effects in proportion of soft shell eggs, proportion of abnormal-shape eggs, albumen height, haugh unit, and eggshell thickness were observed among all treatments (P > 0.05). For serum biochemical parameters, total protein and albumin were increased in MOS diets during 0 to 4 wk of age, but decreased during 5 to 9 wk of age. For serum antioxidant index, superoxide dismutase and glutathione peroxidase values were increased whereas malondialdehyde values were decreased in MOS diets from 0 to 9 wk of age. The results suggest that MOS positively affects early growth performance and laying performane of duckling but partially affects egg quality. The antioxidative activity and immunological index may be improved.


Asunto(s)
Alimentación Animal/análisis , Antioxidantes/metabolismo , Patos/fisiología , Inmunidad/efectos de los fármacos , Moringa oleifera/química , Animales , Dieta/veterinaria , Suplementos Dietéticos/análisis , Relación Dosis-Respuesta a Droga , Patos/crecimiento & desarrollo , Femenino , Tallos de la Planta/química , Distribución Aleatoria , Reproducción
7.
Beijing Da Xue Xue Bao Yi Xue Ban ; 51(5): 881-886, 2019 Oct 18.
Artículo en Chino | MEDLINE | ID: mdl-31624393

RESUMEN

OBJECTIVE: To compare the corneal biomechanical properties among keratoconus, subclinical keratoconus and normal corneas by using CorVis ST, and to estimate the effect of these biomechanical indices in discriminating keratoconus and subclinical keratoconus from normal. METHODS: A total of 76 eyes of 67 subjects were enrolled and divided into three groups. Keratoconus group included 24 eyes from 17 patients, subclinical keratoconus group included 12 eyes from 12 patients and normal group included 40 normal eyes from 40 subjects.All the eyes were assessed with CorVis ST and ten biomechanical parameters, intraocular pressure (IOP) and central corneal thickness (CCT) were obtained from this machine. The discrimination of biomechanical characteristic of the three groups based on the all indices was reflected by discriminant analysis and the Fisher discriminant function was established. RESULTS: The values of corneal biomechanics of keratoconus, subclinical keratoconus, normal eyes were increased in sequence, except for three indices: the second applamation time (A2T), time taken to reach highest concavity (HCT) and maximum corneal velocity during the first applanation (Vin). Three sets of data were among a statistically significant difference (P<0.05). There were statistically significant differences (P<0.05) between any two groups by comparing with such two indices: radius value of central concave curvature at highest concavity (HCR) and CCT. The grades of the three groups were obvious, evaluated by the discriminant function. The accuracy of reevaluation was 85% by validation method. The biggest contribution of indices in discriminant function was given by such four indices in sequence: CCT, HCR, maximum deformation amplitude of highest concavity (HCDA) and maximum corneal velocity during the second applanation (Vout). CONCLUSION: The corneal biomechanical properties of keratoconus and subclinical keratoconus were decreased compared with normal eyes. The biomechanical parameters based on CorVis ST showed a good performance for discriminating among keratoconus, subclinical keratoconus and normal corneas.


Asunto(s)
Queratocono , Fenómenos Biomecánicos , Córnea , Análisis Discriminante , Humanos , Tonometría Ocular
8.
Phys Rev Lett ; 122(17): 176403, 2019 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-31107058

RESUMEN

Cuprate superconductors host a multitude of low-energy optical phonons. Using time- and angle-resolved photoemission spectroscopy, we study coherent phonons in Bi_{2}Sr_{2}Ca_{0.92}Y_{0.08}Cu_{2}O_{8+δ}. Sub-meV modulations of the electronic band structure are observed at frequencies of 3.94±0.01 and 5.59±0.06 THz. For the dominant mode at 3.94 THz, the amplitude of the band energy oscillation weakly increases as a function of momentum away from the node. Theoretical calculations allow identifying the observed modes as CuO_{2}-derived A_{1g} phonons. The Bi- and Sr-derived A_{1g} modes which dominate Raman spectra in the relevant frequency range are absent in our measurements. This highlights the mode selectivity for phonons coupled to the near-Fermi-level electrons, which originate from CuO_{2} planes and dictate thermodynamic properties.

9.
Phys Rev Lett ; 122(16): 167401, 2019 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-31075004

RESUMEN

We study the microscopic origins of photocurrent generation in the topological insulator Bi_{2}Se_{3} via time- and angle-resolved photoemission spectroscopy. We image the unoccupied band structure as it evolves following a circularly polarized optical excitation and observe an asymmetric electron population in momentum space, which is the spectroscopic signature of a photocurrent. By analyzing the rise times of the population we identify which occupied and unoccupied electronic states are coupled by the optical excitation. We conclude that photocurrents can only be excited via resonant optical transitions coupling to spin-orbital textured states. Our work provides a microscopic understanding of how to control photocurrents in systems with spin-orbit coupling and broken inversion symmetry.

10.
Zhonghua Yi Xue Za Zhi ; 98(16): 1227-1230, 2018 Apr 24.
Artículo en Chino | MEDLINE | ID: mdl-29747309

RESUMEN

Objective: To explore the spectrum of causes for patients with vertigo or dizziness in the Department of Neurology, and provide a reference for diagnosis and treatment of patients with vertigo or dizziness. Methods: Clinical data of patients in the Department of Neurology, Baotou Central Hospital between January 2016 and September 2017 was retrospectively analyzed. The target group under study was diagnosed based on the uniform diagnostic criteria. Results: A total of 9 200 patients with a chief complaint of vertigo or dizziness were included. The ratio of male to female was 1∶1.8, with an age range of 19 to 85 years. The different etiology was as follows: benign paroxysmal positional vertigo (BPPV) (3 148 cases, 34.22%), persistent postural-perceptual dizziness (PPPD) (2 006 cases, 21.80%), vertigo caused by cerebrovascular diseases (1 463 cases, 15.90%), vestibular neuritis (741 cases, 8.05%), vestibular migraine (536 cases, 5.83%), vestibular paroxysmia (336 cases, 3.65%), Ménière disease (187 cases, 2.03%), drug-induced vertigo (96 cases, 1.04%), neurological degenerative diseases (74 cases, 0.80%), sudden sensorineural hearing loss (51 cases, 0.55%), multiple sclerosis and neuromyelitis optica (21 cases, 0.23%), other reasons (22 cases, 0.24%), unknown reasons (519 cases, 5.64%). Conclusions: Dizziness is resulted from various causes, and BPPV is the most common reason. Vertigo caused by cerebrovascular diseases appears to gradually increase along with age. PPPD is very common in clinical practice, so clinicians needs to be highly aware of BPPV and PPPD. Although those dizziness diseases have a low incidence, they should not be ignored. There are still certain proportion of vertigo patients whose diagnosis are undetermined.


Asunto(s)
Mareo , Adulto , Anciano , Anciano de 80 o más Años , Vértigo Posicional Paroxístico Benigno , Femenino , Pérdida Auditiva Súbita , Humanos , Masculino , Enfermedad de Meniere , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
11.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 36(11): 830-833, 2018 Nov 20.
Artículo en Chino | MEDLINE | ID: mdl-30646646

RESUMEN

Objective: To investigate the usage frequency of radiological diagnosis devices in ten hospitals in Tianjin, China, and to provide a basis for the survey of medical radiation frequency in Tianjin. Methods: Ten hospitals from the ten districts in Tianjin were enrolled as subjects by a convenient sampling method. A survey was conducted to assess the general information and radiological diagnosis device information and usage frequency in those hospitals in 2016. The radiological examination frequency in Tianjin was estimated. Results: A total of 610 458 patients received radiological examinations in the sampled hospitals in 2016. In those patients, 371 882 received X-ray examinations for imaging and 238 576 for computed tomography (CT) ; there were slightly more female patients than male patients, suggesting a relatively equal gender distribution; patients older than 40 years accounted for 65.53%, which was the highest among all the age groups. Different types of radiological diagnosis devices were mostly used in tertiary and secondary hospitals. In Tianjin, the estimated frequency of X-ray examination for imaging and CT scanning was 451 and 188 per thousand people, respectively, in 2016. Conclusion: The frequency of radiological diagnosis is relatively high in the ten hospitals in Tianjin. The investigation of medical radiation in Tianjin needs to be improved.


Asunto(s)
Hospitales , Radiografía/estadística & datos numéricos , China , Femenino , Humanos , Masculino , Tomografía Computarizada por Rayos X/estadística & datos numéricos
12.
Zhonghua Fu Chan Ke Za Zhi ; 52(11): 740-744, 2017 Nov 25.
Artículo en Chino | MEDLINE | ID: mdl-29179268

RESUMEN

Objective: To investigate the natural changes of high-risk HPV (HR-HPV) in women with negative for intraepithelial lesion or malignancy (NILM) for regulating HR-HPV screening. Methods: Four hundred and thirty-three newly-diagnosed women were enrolled from January 1st, 2015 to December 31, 2015 in Beijing Obstetrics and Gynecology Hospital. The ages of these patients were between 22 and 74 years, the average age was (45±21) years old. Two hundred and sixty-three cases were less than 50 years old, 170 cases were more and equal to 50 years old. One hundred and fifty-six cases were HR-HPV positive, 277 cases were HR-HPV negative. Follow up tests were conducted for all 433 patients, who were screened by ThinPrep cytologic test (TCT) combined with HR-HPV and were diagnosed with NILM, for a period of 1 year (at the 3, 6, 9 and 12 months intervals respectively), if the TCT results are abnormal and the HR-HPV test results are positive, will follow up colposcopy directed cervical biopsy. Results: (1) HR-HPV natural changes: of 156 NILM cases with HR-HPV infection, 42 cases (26.9%, 42/156) turned negative within 3 months, 88 cases (56.4%, 88/156) turned negative within 6 months, 99 cases (63.5%, 99/156) turned negative within 9 months, and 100 cases (64.1%, 100/156) turned negative within 12 months. The negative conversion ratio at 3, 6, 9 and 12 months for women at childbearing age (<50 years) were significantly higher than those at non-childbearing age (≥50 years old; all P<0.05). Of 277 NILM cases without HR-HPV infection, 35 cases (12.6%, 35/277) had new HR-HPV positive infections within 3 months, 70 cases (25.3%, 70/277) had new infections within 6 months, 80 cases (28.9%, 80/277) had new infections within 9 months, and 83 cases (30.0%, 83/277) had new infections within 12 months. The new infections rate at 3, 6, 9 and 12 months for women at childbearing age (<50 years old) were slightly higher than those at non-childbearing age (≥50 years old; all P>0.05). (2) The progress of cervical leision: of 156 NILM cases with HR-HPV positive, no case progressed during 12 months follow-up. Of 277 NILM cases with HR-HPV negative, 4 cases progressed to cervical intraepithelial neoplaisa (CIN) with HR-HPV infection and TCT abnormal during 12 months follow-up, including 2 cases pathology diagnosed with CINⅠ, 1 case with CINⅡ, and 1 case with CINⅢ. The progression rate was 1.4%(4/277), which accounts for 4.8% (4/83) of new HR-HPV infections cases in women. Conclusions: The results of cytology combined with HR-HPV screenings suggest every 6 months for simple HR-HPV positive women, colposcopy directed cervical biopsy is recommended to assess cervical lesions if necessary. Cytology combined with HR-HPV screenings suggest every 12 months for simple HR-HPV negative women to early detection of cervical leision.


Asunto(s)
Colposcopía/estadística & datos numéricos , Progresión de la Enfermedad , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/diagnóstico , Displasia del Cuello del Útero/patología , Neoplasias del Cuello Uterino/patología , Adulto , Anciano , Carcinoma de Células Escamosas , Citodiagnóstico , Femenino , Humanos , Persona de Mediana Edad , Infecciones por Papillomavirus/complicaciones , Embarazo , Estudios Prospectivos , Neoplasias del Cuello Uterino/metabolismo , Displasia del Cuello del Útero/metabolismo
13.
Sci Rep ; 7(1): 10535, 2017 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-28874748

RESUMEN

Deltas are widely threatened by sediment starvation and climate change. Erosion potential is an important indicator of delta vulnerability. Here, we investigate the erosion potential of the Yangtze Delta. We found that over the past half century the Yangtze's sediment discharge has decreased by 80% due to the construction of >50,000 dams and soil conservation, whereas the wind speed and wave height in the delta region have increased by 5-7%, and the sea level has risen at a rate of 3 mm/yr. According to hydrodynamic measurements and analyses of seabed sediments, the period when bed shear stress due to combined current-wave action under normal weather conditions exceeds the critical bed shear stress for erosion (τ cr ) accounts for 63% of the total observed period on average and can reach 100% during peak storms. This explains why net erosion has occurred in some areas of the subaqueous delta. We also found that the increase with depth of τ cr is very gradual in the uppermost several metres of the depositional sequence. We therefore expect that the Yangtze subaqueous delta will experience continuous erosion under sediment starvation and climate change in the next decades of this century or even a few centuries.

14.
Science ; 357(6346): 71-75, 2017 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-28684521

RESUMEN

The interactions that lead to the emergence of superconductivity in iron-based materials remain a subject of debate. It has been suggested that electron-electron correlations enhance electron-phonon coupling in iron selenide (FeSe) and related pnictides, but direct experimental verification has been lacking. Here we show that the electron-phonon coupling strength in FeSe can be quantified by combining two time-domain experiments into a "coherent lock-in" measurement in the terahertz regime. X-ray diffraction tracks the light-induced femtosecond coherent lattice motion at a single phonon frequency, and photoemission monitors the subsequent coherent changes in the electronic band structure. Comparison with theory reveals a strong enhancement of the coupling strength in FeSe owing to correlation effects. Given that the electron-phonon coupling affects superconductivity exponentially, this enhancement highlights the importance of the cooperative interplay between electron-electron and electron-phonon interactions.

15.
Sci Rep ; 7: 41735, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-28145520

RESUMEN

Many deltas are likely undergoing net erosion because of rapid decreases in riverine sediment supply and rising global sea levels. However, detecting erosion in subaqueous deltas is usually difficult because of the lack of bathymetric data. In this study, by comparing bathymetric data between 1981 and 2012 and surficial sediment grain sizes from the Yangtze subaqueous delta front over the last three decades, we found severe erosion and significant sediment coarsening in recent years since the construction of Three Gorges Dam (TGD), the largest dam in the world. We attributed these morphological and sedimentary variations mainly to the human-induced drastic decline of river sediment discharge. Combined with previous studies based on bathymetric data from different areas of the same delta, we theorize that the Yangtze subaqueous delta is experiencing overall (net) erosion, although local accumulation was also noted. We expect that the Yangtze sediment discharge will further decrease in the near future because of construction of new dams and delta recession will continue to occur.

16.
Zhonghua Liu Xing Bing Xue Za Zhi ; 38(1): 128-130, 2017 Jan 10.
Artículo en Chino | MEDLINE | ID: mdl-28100391

RESUMEN

Slow fetal growth is a global public health concern because it might be associated with many diseases later in life. With the progress of technology to measure long-term air pollution exposure. Many epidemiological studies have evaluated the effects of maternal air pollutant exposure on fetal growth. In this paper, we summarize the research progress in this field after the analysis on the related literatures retrieved from the databases of Medline and Web of Science.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Contaminación del Aire/efectos adversos , Desarrollo Fetal/fisiología , Retardo del Crecimiento Fetal/etiología , Salud Pública , Investigación/tendencias , Exposición a Riesgos Ambientales , Femenino , Humanos , Exposición Materna/efectos adversos
17.
Clin Microbiol Infect ; 23(2): 110-116, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27851998

RESUMEN

OBJECTIVES: We studied paediatric patients with human adenovirus (HAdV) infection during the 2011 outbreak in northern Taiwan to define the clinical features of different HAdV genotypes in children. METHODS: Between January and December 2011, 637 patients <19 years of age exhibited culture-confirmed adenoviral infection in Chang Gung Memorial Hospital, and provided specimens available for genotyping by multiplex real-time PCR. Clinical data were collected retrospectively. RESULTS: Excluding five cases with multiple genotypes, 632 cases were included for analysis. Three genotypes were identified, including HAdV-3 (429/632; 67.6%), HAdV-7 (144/632; 22.6%) and HAdV-2 (59/632; 9.8%). Median age was 4.58 years (range 2 months to 18 years), with children infected with HAdV-3 significantly older (82.9% >3 years; p <0.001). Of the 621 inpatients, 98.2% had fevers and all exhibited respiratory symptoms, 75 patients (12.1%) had lower respiratory tract infections, 20 (3.2%) required intensive care (HAdV-2: 1; HAdV-3: 8; and HAdV-7: 11), and three died (all HAdV-7-infected). HAdV-3-infected patients were significantly more likely to have upper respiratory symptoms and a high serum C-reactive protein level >100 mg/L, whereas leucocytosis (white blood cell count >15 000/mm3) was more common in HAdV-2-infected patients (p 0.007). HAdV-7 infections were significantly associated with a longer duration of fever, leucopenia (white blood cell count <5000/mm3), thrombocytopenia (platelet count <150 000/mm3), lower respiratory tract infections, a longer length of hospital stay, and requiring intensive care (all p <0.001). CONCLUSION: Childhood HAdV-2, HAdV-3 and HAdV-7 infections may exhibit different clinical manifestations. Although HAdV-3 was the most prevalent genotype observed during the 2011 Taiwan outbreak, HAdV-7 caused more severe disease characteristics and outcomes.


Asunto(s)
Infecciones por Adenovirus Humanos/epidemiología , Infecciones por Adenovirus Humanos/virología , Adenovirus Humanos/clasificación , Adenovirus Humanos/genética , Genotipo , Infecciones por Adenovirus Humanos/diagnóstico , Infecciones por Adenovirus Humanos/historia , Adolescente , Proteínas de la Cápside/genética , Niño , Preescolar , Comorbilidad , Brotes de Enfermedades , Femenino , Historia del Siglo XXI , Humanos , Lactante , Unidades de Cuidado Intensivo Pediátrico , Tiempo de Internación , Masculino , Filogenia , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/historia , Infecciones del Sistema Respiratorio/virología , Estudios Retrospectivos , Taiwán/epidemiología
18.
Phys Rev E ; 94(3-1): 033202, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27739750

RESUMEN

Filamentation dynamics of relativistic optical vortex beams (OVBs) propagating in underdense plasma is investigated. It is shown that OVBs with finite orbital angular momentum (OAM) exhibit much more robust propagation behavior than the standard Gaussian beam. In fact, the growth rate of the azimuthal modulational instability decreases rapidly with increase of the OVB topological charge. Thus, relativistic OVBs can maintain their profiles for significantly longer distances in an underdense plasma before filamentation occurs. It is also found that an OVB would then break up into regular filament patterns due to conservation of the OAM, in contrast to a Gaussian laser beam, which in general experiences random filamentation.

19.
Zhonghua Yan Ke Za Zhi ; 52(8): 604-9, 2016 Aug.
Artículo en Chino | MEDLINE | ID: mdl-27562282

RESUMEN

OBJECTIVE: To evaluate the effect of long-term contact lens (CL) wear on the morphology of meibomian glands (MGs) using meiboscore and digital analysis. METHODS: Retrospective study. Sixty right eyes of sixty patients were involved in this study, and the data were analyzed retrospectively. According to the duration of CL wear, all patients were divided into three groups, nonwear group (n=21), short-term group (duration of CL wear ≤3 years, n=19) and long-term group (duration of CL wear>3 years, n=20). Digital images of MGs obtained by meibography were analyzed using Image J software, providing the area percentage of MGs loss. The meiboscores were also examined, and the data were analyzed using one-way ANOVA and Kruskal-Wallis test. RESULTS: Ten out of 21 nonwearers were scored 0 point, and 11 were scored 1 point in the upper lid meiboscores, while 7 were scored 0 point, 9 were scored 1 point, and 5 were scored 2 points in the total meiboscores. Seven out of 19 short-term wearers were scored 0 point, 10 were scored 1 point, and 2 were scored 2 points in the upper lid meiboscores, while 5 were scored 0 point, 6 were scored 1 point, 6 were scored 2 points, and 2 were scored 3 points in the total meiboscores. Four out of 20 long-term wearers were scored 0 point, 7 were scored 1 point, and 9 were scored 2 points in the upper lid meiboscores, while 3 were scored 0 point, 4 were scored 1 point, 4 were scored 2 points, 4 were scored 3 points, 4 were scored 4 points, and 1 was scored 5 points in the total meiboscores. The meiboscores of the upper eyelid and total meiboscores among the three groups were significantly different (Hc=9.967, P=0.007; Hc=9.725, P=0.008). The meiboscores of the upper eyelid and total meiboscores were significantly higher in the long-term group compared to the nonwear group (Z=102.500, P=0.003, Z=100.500, P=0.003) and the short-term group (Z=120.500, P=0.050, Z=117.500, P=0.041). No significant difference was found between the short-term group and the nonwear group. The median of the MGs loss area percentage in the upper eyelid of the nonwear, short-term and long-term groups was 9.2%, 13.3% and 16.7%, respectively. The median of the total MGs loss area percentage in the nonwear, short-term and long-term groups were 6.6%, 8.8% and 13.0%, respectively. The above medians were significantly different among the three groups (Hc=6.390, P=0.041; Hc=7.019, P=0.030). They were significantly larger in the long-term wearers than the nonwearers (Z=120.500, P=0.019, Z=120.500, P=0.009). No significant difference was found between the short-term group and the nonwear group, or between the short-term group and the long-term group. No significant differences in the meiboscores or MGs loss area percentage in the lower eyelid were noticed among the three groups. The area under the curve of total area percentage of MGs loss in receiver operating characteristic analysis was 0.981 (P<0.001). CONCLUSIONS: Long-term (more than 3 years) CL wear can cause MGs loss. Digital analysis is helpful in the morphologic evaluation of MGs. (Chin J Ophthalmol, 2016, 52: 604-609).


Asunto(s)
Lentes de Contacto/efectos adversos , Enfermedades de los Párpados/fisiopatología , Glándulas Tarsales/fisiopatología , Estudios de Casos y Controles , Humanos , Glándulas Tarsales/anatomía & histología , Estudios Retrospectivos , Encuestas y Cuestionarios
20.
Phys Rev E ; 93: 043207, 2016 04.
Artículo en Inglés | MEDLINE | ID: mdl-27176418

RESUMEN

Energetic electron acceleration processes in a plasma hollow tube irradiated by an ultraintense laser pulse are investigated. It is found that the longitudinal component of the laser field is much enhanced when a linear polarized Gaussian laser pulse propagates through the plasma tube. This longitudinal field is of π/2 phase shift relative to the transverse electric field and has a π phase interval between its upper and lower parts. The electrons in the plasma tube are first pulled out by the transverse electric field and then trapped by the longitudinal electric field. The trapped electrons can further be accelerated to higher energy in the presence of the longitudinal electric field. This acceleration mechanism is clearly illustrated by both particle-in-cell simulations and single particle modelings.

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