Objective To compare the difference of effect between principal component regression analysis and projection pursuit regression analysis when collinearity exists in data.Methods Evaluating the advantages and disadvantages of the two modeling methods by using the actual data on two aspects:the fitting effect and the predicting effect.Results The principal component regression model showed that the coefficient of determination was 0.8172,the mean of absolute relative error was 6.42％ and the mean square of prediction error was 0.61.The projection pursuit regression model,on the other hand,showed that the coefficient of determination ranged from 0.8851 to 0.9944,the mean of absolute relative error ranged from1.11％ to 4.81％ and the mean square of prediction error ranged from 0.03 to 0.38.Conclusion The analysis results based on the actual data with collinearity indicate that the projection pursuit regression analysis outperforms the principal component regression analysis both in fitting and predicting effect.

Objective To explore the difference of autobiographical memory (AM) between depressive patients with and without alexithymia,and correlation between AM and alexithymia in depressive patients with alexithymia.Methods 29 depressive patients with alexithymia,34 depressive patients without alexithymia were enrolled.All patients were measured by autobiographical memory test (AMT),Toronto alexithymia scale-20 (TAS20),Hamilton depression scale-24 (HAMD-24).Results ①The negative overgeneral AM score was higher in depressive patients with alexithymia than those without alexithymia ((3.34± 1.80),(2.51 ± 1.12),respectively t=2.19,P＜0.05).②The total overgeneral AM score was higher in depressive patients with alexithymia than those without alexithymia ((6.14±2.44),(4.86±2.06),respectively t=2.21,P＜0.05).③)The correlation coefficient (r value) between the total score of overgeneral AM and total score of TAS,TAS-Ⅲ scores of TAS in depressive patients with alexithymia were significantly positively correlated (r=0.240～0.611,P＜0.05).However,the correlation coefficient between the total score of specific AM and total score of TAS,TAS-Ⅲ scores of TAS in depressive patients with alexithymia were significantly negatively correlated(r=-0.502～-0.205,P＜0.05).Conclusion Compared with depressive patients without alexithymia,the overgeneral AM in depressive patients with alexithymia is more severe,and the alexithymia can increase the severity of overgeneral AM.

Objective To analyze the application value of enhanced depth imaging optical coherence tomography (EDI-OCT) in measuring the lamina cribrosa thickness(LCT) in patients with branch retinal vein occlusion (BRVO).Methods The clinical data of 65 patients with unilateral BRVO treated in our hospital from September 2014 to March 2016 were selected as the observation group.The single healthy eyes of 40 healthy individuals who received physical examination in the hospital during the same period were selected as the control group.The changes of retinal nerve fiber layer (RNFL) thickness,LCT,central corneal thickness,axial length,transverse diameter of optic disc,vertical diameter of optic disc,diopter and extent of visual field defect in the two groups were determined by EDI-OCT.Results There was no significant difference in the central corneal thickness,axial length,transverse diameter of optic disc,vertical diameter of optic disc and diopter between the two groups (all P ＞ 0.05).LCT of different regions of optic disc in the observation group were lower than those in the control group (all P ＜ 0.05).The range of visual field defects in the observation group was larger than that in the control group,and the RNFL thickness was lower than that in the control group (P ＜ 0.05).LCT was positively correlated with the thickness of whole RNFL in patients with BRVO,and was negatively correlated with the visual field defects (P ＜ 0.05).Conclusion EDI-OCT is an effective means for measuring LCT.LCT of patients with glaucoma BRVO is thinner than that of normal healthy people,and LCT is positively correlated with RNFL.thickness,and negatively correlated with visual field defects.

Based on the work characteristics of disease and control of People's Liberation Army (PLA), the paper discusses the establishment of quality control system at Institute of Disease and Control of PLA and the subsequent effects. This could provide some reference for improvement disease control of PLA.

Objective:To explore the value of preablative stimulated thyroglobulin (ps-Tg) in predicting distant metastasis (DM) at the time of 131I therapy in children and adolescents with differentiated thyroid cancer (DTC). Methods:From January 2016 to March 2020, 54 children and adolescents who underwent total thyroidectomy due to DTC in Peking Union Medical College Hospital were retrospectively reviewed and divided into 2 groups according to the presence of DM or not: M0 group( n=29, 10 males, 19 females, age (16.3±3.8) years) and M1 group( n=25, 13 males, 12 females, age (12.4±4.3) years). Independent-sample t test, χ2 test (or Fisher′s exact test) and Mann-Whitney U test were used to analyze the general characteristics between the two groups. According to status of regional lymph node (RLN) at the time of 131I therapy, the two groups were further divided into M1RLN+ ( n=8) and M1RLN-( n=17), M0RLN+ ( n=5) and M0RLN-( n=24) subgroups. Mann-Whitney U test was used to analyze the different ps-Tg levels between M0 and M1, M1RLN+ and M1RLN-, as well as M0RLN+ and M0RLN-groups. The receiver operating characteristic (ROC) curve analysis was employed to obtain a cut-off value of ps-Tg as a predictor of DM. Results:Patients with DM tended to have higher ps-Tg level (medians: 406.80 μg/L vs 7.90 μg/L, U=690.000, P<0.001), younger age ( t=-3.559, P=0.001), larger tumor size ( t=3.523, P=0.001), more advanced T stage ( U=506.500, P=0.010) and more multifocality( P=0.013) in comparison with those without DM. Though ps-Tg did not significantly differ between M1RLN+ group and M1RLN-group ( U=98.500, P>0.05) or between M0RLN+ group and M0RLN-group ( U=63.000, P>0.05), the two RLN+ groups tended to hold higher medians than the two RLN-groups (18.05 vs 5.71 μg/L; 1 698.50 vs 216.40 μg/L). In order to avoid the possible influence on the ps-Tg cut-off value, 13 RLN+ samples were removed, and the area under the ROC curve was 0.946 (95% CI: 0.883-1.000). The ps-Tg level of 55.87 μg/L was established as the optimal cut-off value to distinguish M0RLN- from M1RLN-, with the sensitivity and specificity of 14/17 and 95.8%(23/24), respectively. Conclusion:Ps-Tg holds a high predictive value in identifying DM, which may be of great help in avoiding inadequate 131I treatment in children and adolescents with metastatic DTC ignored by radiological examinations.

Background and purpose:The incidence of thyroid cancer (TC) is increasing worldwide. However, there were some differences among different regions. The purpose of this study was to investigate the incidence trends and clinicopathological characteristics of TC in Qingdao, a typical eastern coastal city, and to analyze the change in etiological spectrum of surgical thyroid diseases in recent years.Methods:A total of 2 251 patients who underwent thyroidectomy in 2014 due to thyroid nodules at the Affiliated Hospital of Qingdao University were retrospectively reviewed. The clinico-pathological characteristics were further analyzed among 1 306 patients with TC and compared with the corresponding data from the Surveillance Epidemiology and End Results (SEER) database as well as previous data from this hospital.Results:With the increasing number of thyroidectomy in Qingdao, there was also an increase in the proportion of TC in patients after thyroidectomy, from 34.8% in 2010 to 59.0% in 2014. Among those with TC, the male-to-female ratio was 1∶2.80, with a relatively high incidence among 20-54 year-old adults, who were younger than those reported in terms of distribution of age in SEER database (U=2 289,P=0.000). About 50.2% of the TC patients were overweight or obese, 78.2% TC patients had only asymptomatic nodules detected by ultrasound at initial diagnosis, while 16.6% had visible or palpable thyroid nodules. Only 5.2% presented hoarseness or other repression symptoms. Micro-carcinoma accounted for 61.7% of TC in 2014 at this hospital, which was significantly higher than the proportion in 2010 (37.7%). Lymph node involvement was significantly more frequent at this hospital than in SEER database (49.5%vs 26.0%,χ2=11.806,P=0.001). Even among patients with micro-carcinoma, 31.3% already presented lymph node metastases. The proportions of papillary, follicular, medullary and anaplastic carcinoma were 97.5%, 1.1%, 1.0% and 0.5%, respectively, among which the percentage of papillary carcinoma was higher than that in SEER database (U=4 654.5,P=0.055).Conclusion:There was an increase in the number of thyroidectomy in Qingdao, and the preoperative diagnostic accuracy of TC in this area kept rising. The in-cidence of TC was relatively high in a younger population, with more common lymph node involvements and an overweight trend. The increasing proportion of micro-carcinoma might be related to the popularization of health examination. However, the frequent lymph node metastasis in patients with micro-carcinoma is an important indicator of the invasive behavior of micro-carcinoma, which should not be overlooked.

ObjectiveTo investigate the effect of surgery treatment for syringomyelia associated with spinal cord type cervical spondylopathy.MethodsExpansive open-door laminectomy and spinal cavity-subarachnoid drainage were performed in 11 cases.ResultsThe extremity function of 11 cases were all recoverd to varied extent in the following 1-5 years(average follow-up:30 months).ConclusionsExpansive open-door laminectomy and spinal cavity-subarachnoid drainage is an effective method for syringomyelia associated with spinal cord type cervical spondylopathy.

Risk assessment is critical to responses to public health emergencies .Practices and researches concerning risk assessment of public health emergencies in China′s military are still in the early stage .This paper summarizes the rele-vant concepts , categorization , assessment methods , and practices .Based on management requirements of risk assessment , suggestions are raised about how to strengthen the risk assessment capability of Armed Forces by formulating management rules, perfecting assessment methods and developing assessment tools .

Poor dietary habit is an important cause of the global prevalence of metabolic associated fatty liver disease (MAFLD), and the adjustment of dietary pattern is the cornerstone of MAFLD management. In recent years, a large number of new dietary intervention methods have been proposed and applied in the treatment of MAFLD, including calorie restrict diet, low-carbohydrate diet, low-glycemic index diet, low free sugar diet, intermittent fasting pattern, high protein diet, and Mediterranean diet, and these new methods have different effects in clinical practice. This article introduces the treatment concepts and practical methods of these new dietary treatment strategies and the evidence of their benefits in the treatment of MAFLD in China and globally, so as to provide a new perspective for clinicians to guide patients to achieve individualized nutritional therapy.

Objective To explore the prevalence of food intolerance and its determinants in healthcare elderly in China.Methods A cross sectional survey was carried out from August 1st,2008 to June 30th,2009,that including 736 60-year-olds from a Health Management Research Institute,Chinese PLA General Hospital.Data was double entried in computer and organized by EpiData 3.0.Non conditional logistic regression model was used for odd ratio (OR)and 95％CI,with the use of SPSS 13.0.Results The three leading foodstuff on intolerance were crab,egg and shrimp,with the prevalence rates as 35.9％,28.8％ and 15.1％ respectively.Results from the multiple regression analysis showed that the crab intolerance was associated with Helicobacter pylori infections (P＜0.05).The OR (95％CI) of Helicobacterpylori infections (DOB≥4) was 1.544 (1.139-2.091).Conclusion The three leading intolerance foods were egg,crab and shrimp.Crab intolerance was associated with Helicobacter pylori infections.To reduce the risk of crab intolerance,it was necessary to control the infection caused by Helicobacter pylori.