The development of longitudinal cohorts has made the identification and surveillance of multiple biological markers and behavioral factors which influence disease course or health status become possible. However, traditional statistical methods typically use univariate longitudinal data for research, failing to fully exploit the information from multivariate longitudinal data. The group-based multi-trajectory model (GBMTM) emerged as a method to study the developmental trajectory of multivariate data in recent years. GBMTM has distinct advantages in analyzing multivariate longitudinal data by identifying potential subgroups of populations following similar trajectories by multiple indicators that influence the outcome of interest. In this study, we introduced the application of GBMTM by explaining the fundamental principles and using the data from a health management study in the elderly by using smart wearing equipment to investigate the relationship between multiple life-related variables and hypertension to promote the wider use of GBMTM in longitudinal cohort studies.

Objective:To explore the central venous catheter maintenance compliance among nurses in Class Ⅱ and Ⅲ hospitals in Hunan Province.Methods:From January to March 2022, 297 nurses from 22 Class Ⅱ and Ⅲ hospitals in Hunan Province were selected as the research subject by convenience sampling. Nurses were surveyed using the self-made Central Venous Catheter Maintenance Compliance Questionnaire. Multiple linear regression was used to analyze the influencing factors of nurse compliance with central venous catheter maintenance, the items of the Central Venous Catheter Maintenance Compliance Questionnaire were analyzed.Results:A total of 297 questionnaires were distributed, and 268 valid questionnaires were collected, with an effective response rate of 90.24%. The hospital level, specialized training in intravenous therapy, and age were the influencing factors on the compliance of nurses with central venous catheter maintenance. Analyzing specific items, only 34.3% (92/268) of nurses correctly executed the item "alcohol cotton pads were recommended", and only 66.4% (178/268) of nurses correctly performed the item "sterile gauze dressings should be replaced at least every two days".Conclusions:There is a certain gap in the central venous catheter maintenance compliance among nurses at all levels of hospitals, and there is a need to improve compliance in disinfection of infusion joints and replacement of sterile gauze dressings. We should strengthen the training of specialist nurses, especially the training of nurses in ClassⅡ hospitals on specialized skills related to intravenous therapy.

Objectives:To explore the risk factors for death from ruptured acute aortic dissection during emergency treatment,construct and validate a risk prediction model for death from ruptured acute aortic dissection during emergency treatment. Methods:A total of 301 cases of acute aortic dissection patients who were admitted to Chinese Academy of Medical Sciences Fuwai Hospital from January 2018 to August 2021 were included in this study.Patients were divided into survival subgroup(n=239)and death subgroup(n=62)according to whether dissection rupture occurred in the acute stage of the disease.Univariate and multivariate analyses were performed.Logistic regression analysis was used to establish the risk prediction model.The Hosmer-Lemeshow test was conducted to assess the model's goodness of fit,and the receiver operating characteristic curve(ROC curve)was used to evaluate the model's predictive performance.A prospective validation was performed on 129 cases of acute aortic dissection patients admitted to our hospital's emergency department from September 2021 to September 2022. Results:Among the 301 cases of acute aortic dissection patients,there were 62 cases of rupture and death,with an incidence rate of 20.6%.The results of multivariate analysis showed that age(OR=1.066,95%CI:1.034-1.099),type A dissection(OR=0.045,95%CI:0.006-0.364),history of hypertension(OR=0.377,95%CI:0.167-0.850),and concomitant hypotension(OR=4.424,95%CI:1.467-13.340)were determinants of deaths.The model formula was Z=-5.624+0.064×age-0.976×history of hypertension(yes=1,no=0)-3.104×type(Type A=0,Type B=1)+1.487×concomitant hypotension(yes=1,no=0).The Hosmer-Lemeshow test result showed χ2=9.328,df=8,P=0.315,the area under the ROC curve was 0.874,sensitivity was 79.0%,specificity was 81.6%,and the maximum Youden index was 0.606.The model validation result showed that the area under the ROC curve was 0.722,sensitivity was 73.7%,specificity was 69.1%,and accuracy was 89.9%. Conclusions:Age,history of hypertension,dissection type,and combined hypotension are predictors of the risk prediction model for death from dissection rupture in patients with acute aortic dissection during emergency treatment.The model constructed in this study has good predictive performance,which can provide reference for medical staffto quickly identify high-risk patients for death from ruptured acute aortic dissection and timely predictive measures could be highlighted in indicated cases.

Objective:To explore the developmental characteristics of different cognitive styles on verbal and visuospatial working memory of primary school students.Methods:The Mosaic graph test was used to test the cog-nitive style of students in grades 2,4 and 6.The three-factor mixed experiment of 2(cognitive style:field independ-ent,field dependent)× 3(grade:2,4,6)× 2(task type:letter task,spatial task)was carried out.The 2-back task was used to measure the working memory characteristics of students with different cognitive styles,and the repeated measurement ANOVA was performed on the accuracy of letter and spatial tasks of 175 effective subjects.Results:The accuracy of letter task and spatial task of field independent primary school students were higher than that of field-dependent primary school students(P＜0.001).The accuracy rate of letter task for field independent primary school students was higher than that of space task(P＜0.001).The accuracy of two kinds of tasks of field inde-pendent students in grade 6 was better than that of field independent students in grade 2 and grade 4(P＜0.05).Conclusion:There are differences in the development of verbal and visuospatial working memory of primary school students with different cognitive styles,which may also be related to task type and age.

Abstract Allergic diseases can occur in all systems of the body, covering the whole life cycle, from children to adults and to old age, can be lifelong onset and even fatal in severe cases. Children account for the largest proportion of the victims of allergic disease, Children s allergies start from scratch, ranging from mild to severe, from less to more, from single to multiple systems and systemic performance, so the prevention and treatment of allergic diseases in children is of great importance, which can not only prevent high risk allergic conditions from developing into allergic diseases, but also further block the process of allergy. At present, there is no consensus on the management system of allergic children in kindergartens and primary schools. The "Consensus on Allergy Management and Prevention in Kindergartens and Primary Schools", which includes the organizational structure, system construction and management of allergic children, provides evidence informed recommendations for the long term comprehensive management of allergic children in kindergartens and primary schools, and provides a basis for the establishment of the prevention system for allergic children.

Objective:To analyze the clinical efficacy of treatment of cement dislodgement after vertebral augmentation for osteoporotic vertebral fractures.Methods:A retrospective study was conducted to analyze the data of 13 patients who had been treated at Department of Orthopaedics, The First Affiliated Hospital of Soochow University for cement dislodgement after vertebral augmentation for osteoporotic vertebral fractures from July 2013 to July 2022. There were 4 males and 9 females, with an average age of (76.5±8.6) years and a T value of bone mineral density of -3.3±0.6. By the CT and MRI features of cement dislodgement, their conditions fell in 4 types: cement loosening in situ (4 cases), anterior cement moving (6 cases), anterior cement moving with posterior bone mass moving (2 cases), and posterior cement moving (1 case). They were treated by percutaneous vertebroplasty (3 cases), pedicle screw fixation combined with bone graft fusion and decompression (7 cases), and conservative therapy (3 cases). The curative effects for surgical patients were evaluated by comparing their visual analogue scale (VAS), Oswestry dysfunction index (ODI) and cobb angle of kyphosis at preoperation, 1 week and 1 month postoperation, and the last follow-up, and Frankel grading for nerve injury as well. The curative effects for patients undergoing conservative treatment were evaluated by observing their symptoms.Results:This cohort was followed up for 7 (5, 12) months after treatment. The VAS scores [5.0 (4.0, 5.0) points, 3.0 (2.0, 3.0) points, and 3.0 (2.0, 3.0) points] in the 10 surgical patients at 1 week and 1 month postoperation and the last follow-up were significantly improved compared with the preoperative value [8.5 (8.0, 9.0) points] ( P<0.05); the VAS scores at 1 month postoperation and the last follow-up were also significantly improved compared with that at 1 week postoperation ( P < 0.05), but there was no significant difference between the last follow-up and 1 month postoperation ( P > 0.05). The ODIs (50.6%±4.2%, 37.8%±4.5%, and 29.3%±5.6%) in the 10 surgical patients at 1 week and 1 month postoperation and the last follow-up were significantly improved compared with the preoperative value (93.2%±3.6%), showing significant differences in pairwise comparisons ( P<0.05). The cobb angles [10.0 (9.0, 11.0)°, 9.0 (9.0, 11.0)°, and 10.0 (9.0, 12.0)°] in the 10 surgical patients at 1 week and 1 month postoperation and the last follow-up were significantly improved compared with the preoperative value [12.5 (11.0, 14.0)°] ( P<0.05) , but there was no statistically significant difference between the time points after operation ( P>0.05). The Frankel grading was significantly improved in the 6 patients with nerve injury after operation. Of the 3 patients undergoing conservative treatment, the symptoms were cured in one, showed no change during follow-up in one, and aggravated in one. Conclusion:Surgical treatment can significantly relieve pain, improve spinal dysfunction and repair nerve injury in patients with bone cement dislodgement after vertebral augmentation.

Objective: To investigate the value of serum hepcidin in assessment of liver inflammation activity among patients with chronic hepatitis B ( CHB ), so as to provide insights into the assessment of liver inflammation activity among CHB patients. Methods: A total of 79 CHB patients who were admitted to the Affiliated Hospital of Hangzhou Normal University were selected as the experimental group, while 40 healthy volunteers were randomly sampled as controls. Subjects'demographic data, liver function tests and iron metabolism parameters were collected from medical records, and serum hepcidin was measured using enzyme-linked immunosorbent assay ( ELISA ). In addition, ultrasound-guided liver biopsy was performed in CHB patients, and mild and moderate-to-severe CHB were classified according to liver inflammation activity and degree of liver fibrosis. Serum hepcidin levels were compared between the experimental and control groups and between patients with mild and moderate-to-severe CHB. The value of serum hepcidin in assessment of liver inflammation activity was examined among CHB patients using the receiver operating characteristic ( ROC ) curve analysis. Results: Subjects in the experimental group included 54 men ( 68.35% ) and had a mean age of ( 39.06±10.67 ) years, while the controls included 24 men (60.00%) and had a mean age of ( 42.43±11.44 ) years. Lower hepcidin levels were measured in the experimental group than in the control group [( 11.70±5.64 ) vs. ( 17.82±3.63 ) μg/L; P<0.05 ]. There were 54 patients with mild CHB ( 68.35% ) and 25 cases with moderate-to-severe CHB ( 31.65% ), and lower hepcidin levels were detected in patients with moderate-to-severe CHB than in those with mild CHB [ ( 6.92±2.21 ) vs. ( 13.95±5.36 ) μg/L; P<0.05 ]. The area under the ROC curve, optimal cut-off, sensitivity and specificity of serum hepcidin were 0.903 ( P<0.05 ), 10.365 μg/L, 100.0% and 72.2% for assessment of moderate-to-severe CHB, respectively. Conclusion Serum hepcidin is feasible to evaluate the liver inflammatory activity among patients with CHB.

Objective:To compare the clinical results of different endovascular thrombus reduction techniques in the treatment of acute lower extremity arterial thrombosis.Methods:The clinical data of 96 consecutive patients with acute femoral popliteal arterial thrombosis who were treated with catheter directed thrombolysis (CDT) and mechanical thrombus aspiration system (PMT) between Jan 2016 and Dec 2018 at Cangzhou People's Hospital and Peking University People's Hospital were retrospectively analyzed.Results:Ninty-six patients underwent thrombolytic surgery,including 36 with CDT thrombolysis, 28 with AngioJet aspiration alone and 32 with Rotarex aspiration alone. Angiojet thrombus aspiration reduced thrombus rate by 89.3% (25/28) and clinical success rate by 92.8% (26/28).The thrombus reduction rate of Rotarex group was 87.5% (28/32), and the clinical success rate was 96.8% (31/32). In the CDT thrombolytic group, the thrombolytic reduction rate was 61.1% (22/36), including 8 patients who underwent thrombectomy and 6 patients with PMT, with a clinical success rate of 86.1% (31/36). The rate of distal arterial embolization, puncture point and local subcutaneous hematoma and vascular rupture was 21.4%, 10.7% and 2.1%, respectively. There were no amputation cases reported during a mean 13 months follow-up.The survival rate was 97.9%. The first-stage patency rate of 67.8%, while the second-stage artery patency rate of 85.7% during the follow-up.Conclusion:Compared with CDT, PMT has higher efficiency and lower complication rate in the treatment of acute lower extremity arterial thrombosis.

Objective:To investigate the extent of statistics anxiety and explore its influencing factors among university students majoring in medicine.Methods:The statistics anxiety rating scale (STARS) was first translated into Chinese and modified until the reliability and validity were acceptable. Through online questionnaire, the Chinese version of STARS was used to measure the level of statistics anxiety for students enrolling in the course of Medical Statistics during autumn term 2018 to spring term 2019 in the medical college of a university. The collected data were managed and analyzed by SPSS 25.0.Results:A total of 562 students took part in the survey, and 500 questionnaires were eligible and included in the final analysis. The measurement of Chinese version of STARS showed quite good reliability and validity, with item score of the whole scale being (2.31 ± 0.65) points. The proportions of students with mild, moderate and severe statistics anxiety were 41%, 56% and 3% respectively. Female students had higher extent of anxiety than male students, and undergraduates had higher extent of anxiety than postgraduates. The extent of anxiety of students with different majors from high to low were nursing > (dentistry, basic medicine and pharmacology) > (clinic medicine and public health) respectively. When controlling other factors, the influence of gender, student level and major on statistics anxiety was still statistically significant.Conclusion:Statistics anxiety is prevalent in medical college students. Professional teachers should pay more attention to students' psychological status, conduct targeted counseling to alleviate students' anxiety and help them to improve self-efficacy in statistics learning.

OBJECTIVE：To optim ize the ultrafiltration technology of enzymatic hydrolysate from Eucommia ulmoides peel. METHODS：The single factor test was adopted to investigate the effects of molecular weight of ultrafiltration membrane ，liquid temperature，operating pressure ，operating frequency ，membrane filtration time ，liquid concentration and pH on transfer rates of aucubin，geniposide and chlorogenic acid as well as solid removal rate in enzymatic hydrolysate from E. ulmoides peel. Setting the molecular cut off of fixed ultrafiltration membrane of 100 000，liquid concentration of 7 g/L，and pH value of 7，the ultrafiltration technology was optimized by Box-Behnken design response-surface methodology and validated with liquid temperature ，operating pressure，operating frequency and membrane passing time as factors ，using comprehensive scores calculated from transfer rates of aucubin，geniposide and chlorogenic acid as well as solid removal rate as indexes. RESULTS ：The optimal ultrafiltration technology of enzymatic hydrolysate from E. ulmoides peel was as follows as liquid temperature of 35 ℃，operating pressure of 0.5 MPa，operating frequency of 35 Hz and membrane passing time of 42 min. Results of validation tests showed that the comprehensive scores of the transfer rates of aucubin ，geniposide and chlorogenic acid as well as solid removal rate in enzymatic hydrolysate from E. ulmoides peel was 78.06％（RSD＝1.43％，n＝3），and its relative error with the predicted value （77.18％） was 1.14％. CONCLUSIONS ：The optimized ultrafiltration technology is stable and reliable ，and can be used for the ultrafiltration purification of enzymatic hydrolysate from E. ulmoides peel.