OBJECTIVE: To establish a SEIR epidemic dynamics model that can be used to evaluate the COVID-19 epidemic, and to predict and evaluate the COVID-19 epidemic in Hubei province using the proposed model. METHODS: COVID-19 SEIR transmission dynamics model was established, which took transmission ability in latent period and tracking quarantine interventions into consideration. Based on the epidemic data of Hubei province from January 23, 2020 to February 24, 2020, the parameters of the newly established modified SEIR model were fitted. By using Euler integral algorithm to solve the modified SEIR dynamics model, the epidemic situation in Hubei province was analyzed, and the impact of prevention and control measures such as quarantine and centralized treatment on the epidemic development was discussed. RESULTS: The theoretical estimation of the epidemic situation by the modified SEIR epidemic dynamics model is in good agreement with the actual situation in Hubei province. Theoretical analysis showed that prevention and control quarantine and medical follow-up quarantine played an important inhibitory effect on the outbreak of the epidemic.The centralized treatment played a key role in the rapid decline in the number of infected people. In addition, it is suggested that individuals should improve their prevention awareness and take strict self-protection measures to curb the increase in infected people. CONCLUSIONS The modified SEIR model is reliable in the evaluation of COVID-19 epidemic in Hubei province, which provides a theoretical reference for the decision-making of epidemic interventions.
Algorithms ; Betacoronavirus ; isolation & purification ; China ; epidemiology ; Coronavirus Infections ; epidemiology ; Humans ; Models, Biological ; Pandemics ; Pneumonia, Viral ; epidemiology

Objective To investigate the rehabilitation needs and technical support for people with disabilities in rural areas. Methods From October, 2017 to February, 2018, 800 persons with disabilities, aged five to 80 years, from 23 villages in five township, Xi'an, Shaanxi, were surveyed with self-designed questionnaire and interview, including the basic situation, disability and training plan, rehabilitation support and skills maintained. Results The persons were mainly aged 50 to 80 years (58.37%), male (65.37%), accepting middle school education or less (46.63%), married (70.63%), living with their family (77.38%), income less than 2000 Yuan (66%), mainly from their family labor (62.62%). Their disabilities were mainly of grade 3 (40.63%), from hemiplegia (30.63%), dependence in living (45.38%), and no systematic rehabilitation program (55.25%). Most of them needed rehabilitation of self-care (40%), accessible guidance (30.63%) and reimbursement from medicare of Rural Cooperative Medical Scheme (50.63%), and hoped to participate social activities (41.87%). The rehabilitation supports were as that: the rehabilitation services were mobile or none (67.58%), the guiders of rehabilitation were few or none (48.88%), knew some or less rehabilitation knowledge (64.25%), the professionals accepted no continue education training (40%).Conclusion It is important to improve the rehabilitation technical support system for rural people with disabilities.

The global prevalence rate of nonalcoholic fatty liver disease (NAFLD) has increased year by year, and it has become the number one cause for chronic liver disease in China. In addition, the trend of NAFLD has become more pronounced and evident in female gender and younger age group. The long-term persistence of fatty liver disease may cause serious consequences. There are no accepted diagnostic criteria for diagnosing noninvasive diagnosis of NAFLD. Alpha-ketoglutarate is a newly discovered serological marker of high diagnostic value and considered the most valuable potential biomarker along with cytokeratine-18 (CK-18).

OBJECTIVETo investigate the capability of semi-quantitative and quantitative parameters of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to predict the response to concurrent chemoradiotherapy( CCRT) in patients with non-small cell lung cancer (NSCLC).

METHODSA total of 24 patients with stage III or IIIB NSCLC, who underwent 3.0T DCE-MRI before CCRT, were enrolled in this study. Semi-quantitative and quantitative parameters were calculated by Funtool and Omnikinetics software. The relationship between these obtained parameters and tumor response was evaluated by Spearmen' s correlation analysis. The patients were classified into two groups according to the tumor regression rate after treatment, as response group (group A) and non-response group ( group B). Mann-Whitney U test was used to compare the parameters of responders and non-responders. The value of the parameters on predicting response was calculated by receiver operating characteristic curve (ROC).

RESULTSThe tumor regression rate after treatment was negatively correlated with time to peak (TTP) and the extravascular-extracellular volume fraction (Ve), and was positively correlated with signal enhancement ratio (SERmax) and volume transfer constant (Ktrans) (P < 0.05 for all). Statistical significant differences were found between group A and group B both in semi-quantitative and quantitative parameters (P < 0.05). Group A had a lower TTP value [(34.66 ± 16.37) s vs. (44.09 ± 17.41) s] and Ve value [(0.19 ± 0.03) vs. (0.25 ± 0.05)] than group B, whereas group A had a higher SERmax [(166.50 ± 44.95)% vs. (113.57 ± 46.62)%] and Ktrans [(0.41 ± 0.17) min(-1) vs. (0.28 ± 0.12) min(-1)] than group B (P < 0.05 for all). The ROC analysis indicated that when setting the threshold of Ve on ≤ 0.21 for predicting response, the specificity, sensitivity and accuracy were 85.7%, 80.0% and 83.3%, respectively, with an area under curve of 0.875 (P < 0.001).

CONCLUSIONSBoth the semi-quantitative and quantitative DCE-MRI parameters are helpful for predicting the response after CCRT of NSCLC. Quantitative parameters seem to be more meaningful than semi-quantitative parameters.

Carcinoma, Non-Small-Cell Lung ; pathology ; therapy ; Chemoradiotherapy ; methods ; Contrast Media ; Humans ; Lung Neoplasms ; pathology ; therapy ; Magnetic Resonance Imaging ; methods ; ROC Curve ; Remission Induction ; Sensitivity and Specificity ; Time Factors

Objective To investigate the capability of semi-quantitative and quantitative parameters of dynamic contrast-enhanced magnetic resonance imaging ( DCE-MRI) to predict the response to concurrent chemoradiotherapy( CCRT) in patients with non-small cell lung cancer ( NSCLC) .Methods A total of 24 patients with stageⅢA orⅢB NSCLC, who underwent 3.0T DCE-MRI before CCRT, were enrolled in this study.Semi-quantitative and quantitative parameters were calculated by Funtool and Omnikinetics software. The relationship between these obtained parameters and tumor response was evaluated by Spearmen′s correlation analysis.The patients were classified into two groups according to the tumor regression rate after treatment, as response group ( group A) and non-response group ( group B) .Mann-Whitney U test was used to compare the parameters of responders and non-responders.The value of the parameters on predicting response was calculated by receiver operating characteristic curve (ROC).Results The tumor regression rate after treatment was negatively correlated with time to peak ( TTP ) and the extravascular-extracellular volume fraction ( Ve ) , and was positively correlated with signal enhancement ratio ( SERmax ) and volume transfer constant (Ktrans)(P<0.05 for all).Statistical significant differences were found between group A and group B both in semi-quantitative and quantitative parameters ( P<0.05) .Group A had a lower TTP value [(34.66±16.37)s vs.(44.09±17.41)s] and Ve value [(0.19±0.03) vs.(0.25±0.05)] than group B, whereas group A had a higher SERmax[(166.50±44.95)%vs.(113.57±46.62)%] and Ktrans[(0.41±0.17) min-1 vs.(0.28±0.12) min-1] than group B (P<0.05 for all).The ROC analysis indicated that when setting the threshold of Ve on≤0.21 for predicting response, the specificity, sensitivity and accuracy were 85 .7%, 8 0 .0%and 8 3 .3%, respectively , with an area under curve of 0 .8 7 5 ( P<0 .0 0 1 ) .Conclusions Both the semi-quantitative and quantitative DCE-MRI parameters are helpful for predicting the response after CCRT of NSCLC.Quantitative parameters seem to be more meaningful than semi-quantitative parameters.

Objective To investigate the capability of semi-quantitative and quantitative parameters of dynamic contrast-enhanced magnetic resonance imaging ( DCE-MRI) to predict the response to concurrent chemoradiotherapy( CCRT) in patients with non-small cell lung cancer ( NSCLC) .Methods A total of 24 patients with stageⅢA orⅢB NSCLC, who underwent 3.0T DCE-MRI before CCRT, were enrolled in this study.Semi-quantitative and quantitative parameters were calculated by Funtool and Omnikinetics software. The relationship between these obtained parameters and tumor response was evaluated by Spearmen′s correlation analysis.The patients were classified into two groups according to the tumor regression rate after treatment, as response group ( group A) and non-response group ( group B) .Mann-Whitney U test was used to compare the parameters of responders and non-responders.The value of the parameters on predicting response was calculated by receiver operating characteristic curve (ROC).Results The tumor regression rate after treatment was negatively correlated with time to peak ( TTP ) and the extravascular-extracellular volume fraction ( Ve ) , and was positively correlated with signal enhancement ratio ( SERmax ) and volume transfer constant (Ktrans)(P<0.05 for all).Statistical significant differences were found between group A and group B both in semi-quantitative and quantitative parameters ( P<0.05) .Group A had a lower TTP value [(34.66±16.37)s vs.(44.09±17.41)s] and Ve value [(0.19±0.03) vs.(0.25±0.05)] than group B, whereas group A had a higher SERmax[(166.50±44.95)%vs.(113.57±46.62)%] and Ktrans[(0.41±0.17) min-1 vs.(0.28±0.12) min-1] than group B (P<0.05 for all).The ROC analysis indicated that when setting the threshold of Ve on≤0.21 for predicting response, the specificity, sensitivity and accuracy were 85 .7%, 8 0 .0%and 8 3 .3%, respectively , with an area under curve of 0 .8 7 5 ( P<0 .0 0 1 ) .Conclusions Both the semi-quantitative and quantitative DCE-MRI parameters are helpful for predicting the response after CCRT of NSCLC.Quantitative parameters seem to be more meaningful than semi-quantitative parameters.

Objective: To establish a new method for determining residual organic solvent DMF in imiquimod. Methods: The samples were injected into an Agilent HP-PLOT/Q capillary column(30 m × 0. 530 mm,40. 0 μm) by a headspace sampler and ana-lyzed with an FID detector, the carrier gas was nitrogen, the inlet temperature was 250℃, and the detector temperature was 270℃. The column temperature was programmed raised. Results: The resolution among the peaks of DMF and the other residual solvents could meet the requirements. There was a good linearity within the experimental concentration range. The average recovery was 94. 6%(RSD=4. 0%, n=9). The limit of quantification and the limit of detection was 4. 809μg·ml-1 and 0. 963μg·ml-1, respectively. Conclusion:The method is convenient, accurate and sensitive, which can be used in the determination of residual solvent DMF in imi-quimod.

Objective To analyze the changing rules of schistosomiasis endemic situation before and after reaching the crite-ria of schistosomiasis transmission controlled or transmission interrupted in Zhejiang Province,so as to provide scientific evi-dence for schistosomiasis contro1. Methods Xiuzhou District and Zhuji City were selected and investigated retrospectively to collect schistosomiasis epidemiological information 10 years before they reached the criteria of transmission controlled and the subsequent years until 2008. The database of retrospective investigation was established for analyzing the trends and rules of changes of Oncomelania hupensis snail status and schistosome infection status of cattle and human. Results The snail status and schistosome infection kept a steady declining before reaching the criteria of transmission controlled ,and there were positive correlations between the area of living snails and the infection rates of human and animal in two places(rhuman=0.764,P<0.01, rcatl e=0.709,P<0.01;rhuma=0.775,P<0.01,rcatl e=0.676,P<0.01);No local infection person and animal except residual snails, and found 7 cases of imported infection source were found after reaching the transmission interruption. Conclusion The epi-demic status of schistosomiasis in zhejiang is stable after reaching the criteria of transmission interruption ,and residual snail are easy to re-found and spread under some certain conditions,and some imported cases were found sometimes,which may in-crease the risks for re - emergence of schistosomiasis. The integrated solidification strategy with emphasis on control of residu-al snails and imported cases should be taken in the areas of transmission interruption in the future.

ObjectiveTo observe the changes in TSH receptor antibody (TRAb) and soluble intercellular adhesion molecule-1 ( sICAM-1 ) levels after treatment of propylthiouracil ( PTU ) and methimazole( MMI ) in patients with Graves' disease (GD). MethodsOne hundred and six cases of clinically diagnosed patients with GD were divided into PTU and MMI groups( each group, n =53 ). The patients in two groups were regularly followed for 36 months. TRAb and sICAM-1 were measured with ELISA method. Results( 1 ) The general data of two groups were not significantly different before treatment( all P＞0. 05 ). ( 2 ) There was no difference in TRAb positive rates between two groups before treatment. The clinical remission rates between PTU and MMI groups showed no difference (83.02％ vs88.68％ ). The cure rate was higher in MMI group than in PTU group( 58.49％ vs 37.74％, P＜ 0. 05 ). (3) There existed significant differences in TRAb levels determined before and 6, 12, 24,30, and 36 months after treatment( all P＜0. 01 ), being gradually decreased with time( F=275.48 ,P＜0.01 ). TRAb levels between two groups were significantly different( F=5.86, P＜0. 05 ). (4) sICAM-1 levels at 36 months after treatment compared with the baseline in both groups were statistically different (P＜0. 01 ), but no difference was found between two groups.ConclusionsBoth PTU and MMI improve the immune status of patients with GD,and the immunosuppressive effect of methimazole is more evident.

Objective To increase the mechanic characteristic of bovine jugular veins conduit (BJVC) by combined knitted stent outside made of nylon fiber. Methods Get rid of the cells of BJVC by enzymolysis, then combined a fabric stent with a acellular bovine jugular vein conduit that cross-linked dealed by photooxidation method to improve the mechanic function of BJVC. To compare the mechanical function and histology change of BJVC combined with fiber stent outside with that of BJVC only without stent. BJVC combined with fiber stent outside was divided into experiment group and the latter into control group. Two roller pumps on cardiopulmonary bypass unit were designed to simulate the pulmonary circulation. One produce the stream, and the other assist to bring a certain pressure by regulating a degree of tightness. The pressure of forward stream was used in messuring extension rate and leakage volume of two BJVC groups, and the pressure of backward stream was used in messuring the regurgitation volume. Results Set the formula to calculate the rate of variation of BJVC diameter under a certain pressure or not. The experiment group extension rate was zero under pressure of 10-20 mm Hg, about ( 7.7 ± 2.3 ) % under pressure of 40 mm Hg, until 60 mm Hg to ( 11.4 ± 3.1 ) %. While the control group reached about ( 14.8 ± 4.7 ) % at 20mm Hg already. There was no regurgitation volume of the experiment group under pressure of 30 mm Hg vs. the control group' s reached 34ml/min at 30 mm Hg while the two groups were same under pressure that lower than 20 mm Hg. When the pressure higher, the difference between the two groups more notable. There was no leakage of the BJVCs with fabric stent till pressure from 40 mmHg to 60mmHg, vs. the control group 1,5, 13 ml/min at pressure 30, 40, 60 mm Hg. Except the regurgitation and leakage volumes under pressure at 10 -20 mm Hg, as the two numerical values were both zero that can not be caculated by the statistic software, the differences of the two groups above had statistics significance. In vivo, 9 dogs received bovine jugular vein conduit transplant procedure to observe the mechanic fnction and tissue reaction. Five adopted B.JVC with stent and four just BJVC only. Six month later after the transplant procedure, there was no significant difference between the two groups but more inflaming cells than the former group, especially at the location round the nylon fibers. Through the observation in HE stain, that was considered as foreign body reaction. Conclusion Fabric stent can improve the mechanical function of BJVC and relatively easy to get.