Objective: To understand mental health status of middle school students in Weifang, and to analyze its association with health risk behaviors, and to provide a reference basis for the effective prevention of mental health problems. Methods: Using the self-designed questionnaire and Kessler l0 (K10), a total of 3 185 middle school students in Weifang selected by using stratified clustered sampling were investigated. Chi-square test and binary Logistic regression was used for statistical analysis. Results: Among the middle school students in Weifang, 1 634(51.3%) reported good mental health, 854(26.8%) in moderate level, 394(12.4%) reported poor mental health, and 303(9.5%) reported very poor mental health. Sleep duration and smoking were associated with mental health of middle school students (P<0.05). Logistic regression analyses showed that, compared with adolescents with sleep duration less than 8 h, mental health among students whose sleep duration ≥8 h was better(OR=0.36); compared with non-smokers, students who smoked showed worse mental health status (OR=3.53). Conclusion Health-risk behaviors are closely related to mental health of middle school students. Relevant departments should strengthen education and publicity of healthy lifestyles, and pay close attention to the impact of health risk behaviors on mental health.

Objective:To analyze the equity of health resource allocation in village-level medical institution in China,thus to provide the basis for formulating relevant health resources allocation policy.Methods:Using Lorenz curve and Gini coefficient,the rationality and equity of allocation of village health resources in China were evalua-ted by the equity of population distribution and the equity of geographical distribution.Results:The Gini coefficient of village health workers and health institutions was 0.19 and 0.20 respectively according to population distribu-tion,and was 0.65 and 0.63 respectively according to geographical distribution.The Gini coefficient's difference of village-level health resources in the eastern,central and western regions was small according to population distri-bution,but the difference was larger according to geographical distribution among different areas.Conclusion:The equity of village-level health resource allocation in China was preferable according to population distribution,but the equity according to geographic distribution was poorer.The formulation of health policy should pay more atten-tion to the equity of geographic distribution and allocate rationally.

Objective To evaluate if 18F-FLT PET imaging could be used as a new clinical method to predict tumor radiosensitivity.Methods MDA-MB-231 and LN229 cells were irradiated with doses of 0,8 and 16 Gy of 6 MV photon energy,then soft agar assay and cellular uptake of 18F-FLT were performed on the 2 cell lines.The t test and one-way analysis of variance were used for the two groups and data before and after irradiation.The MDA-MB-231 and LN229 tumor xenografts were prepared by injecting the tumor cells into the right limbs of female BALB/c nu/nu mice.Once tumors reached a diameter of 10 mm,the two types of mice were divided randomly into 3 groups (20 mice per group) according to the irradiation doses (0,8 and 16 Gy).After irradiation,18F-FLT PET imaging and immunohistochemical staining were conducted.Then correlations between 18F-FLT SUVtumor/SUVmuscle ratio (T/M ratio) and TK1 labeling index percentages (LITK1) were tested using linear correlation analysis.Results The survival fraction of MDA-MB-231 and LN229 cells after irradiated with 8 Gy were (59.73 ± 4.3) ％ and (93.41 ± 3.75) ％,respectively (t =-13.20,P ＜ 0.001).When the dose increased to 16 Gy,the survival fraction decreased to (43.57 ±4.06) ％ and (81.77 ± 4.42) ％,respectively(t =-14.24,P ＜ 0.001).In MDA-MB-231 cells,the cellular uptake of 18F-FLT after irradiation with 8 Gy declined rapidly to (18.32 ± 1.38) kBq/105 cells ((128.22 ± 8.24) kBq/105 cells with the dose of 0 Gy,F =266.41,P ＜ 0.01),and maintained this low level till 72 h.For the LN229 cells,the cellular uptake decreased to (9.87 ± 1.30) kBq/105 cells after 8 Gy irradiation ((134.88 ± 6.59) kBq/105 cells with the dose of 0 Gy,F =346.06,P ＜ 0.01),then increased gradually to (127.17 ± 9.08) kBq/105 cells at 72 h (F =346.06,P ＞ 0.05).The dynamic changes of 18F-FLT cellular uptake in the two cells had the same pattern after being treated with 16 Gy irradiation.In the 18F-FLT PET image of MDA-MB-231 tumor mice after 8 Gy radiotherapy,the T/M ratio decreased to 0.78 ± 0.39 at the first day,but it was 2.84 ± 0.29 before radiotherapy (F =39.78,P ＜0.01).Then the ratio increased slowly,and it was still lower than the baseline at 7 d after radiation (F =39.78,P ＜0.01).The same pattern could be seen in the group of 16 Gy irradiation.In LN229 tumor mice treatment with 8 Gy irradiation,the T/M ratio increased to 2.41 ±0.47 at the first day,and it was 1.58 ±0.29 before radiotherapy (F =34.01,P ＜ 0.05).The ratio decreased steadily to 0.66 ± 0.32 (F =34.01,P＜0.05) at 7 d after radiotherapy.However,in the treatment group with 16 Gy,the T/M ratio decreased gradually and reached 0.44 ± 0.22 at 7 d (F =41.85,P ＜ 0.01).A correlation was found between 18F-FLT T/M ratio and LITK1 (8 Gy:r=0.67,0.73; 16 Gy:r=0.73,0.69; all P＜0.01) in both tumor models.Conclusion 18F-FLT PET imaging may be used as a new assay to predict tumor radiosensitivity,but further investigation is needed before clinical application.

Objective To report therapeutic effects of patients with bladder cancer treated by intra-operative radiation and to recommend an effective method for the treatment of bladder cancer.Methods During the operation,when the tumor of bladder had been removed,a boost dose of electric beam from a linear accelerator was irridiated to the tumor bed.28 cases were follawed-up in a long period.Results Lower local recurrence was observed in patients received intra-operative radiation therapy,only 2 cases had a small recurrent tumor in the bladder during the follow-up period.26 cases had bean followed up,no tumor recurred.Conclusion The intraoperative radiation therapy is a useful treatment for the bladder cancer.