Objective:To study the epidemiological features of internet addiction disorder(IAD)in high school students in Beijing and explore the related factors.Methods:A stratified cluster sampling method was used.Totally 5100 high schools students were measured with the Internet Addiction Scale,Personality Diagnostic Questionnaire and Egna Minnen av Bardndoms Uppfostran(EMBU).Results:(1)The prevalence of IAD was 8.8% in high school students in Beijing.(2)Logistic regression analysis indicated that the risk factors of IAD were male,school area in urban area,parents' divorce,parents' refusal,parents' over-protection,paranoid personality disorder,avoidant personality disorder,antisocial personality disorder and histrionic personality disorder.The protective factor was parents' emotional warmth.Conclusion:It should be paid more attention to internet addiction disorder IAD in high school students in Beijing.Prevention and intervention should be conducted to the risk factors of internet addiction disorder IAD.

Objective To study the effect of community health education on lactation mastitis and breast feeding.Method Ninety parturients were given community health education for 6 months and then the rates of mastitis and breast feeding were recorded.Results The mastitis morbidity was 3.3%and the rate of breast feeding was 97.8%.Conclusion The implementation of the community health education can reduce the morbidity of maternal mastitis and raise the rate of breast feeding.

Objective: To explore the apoptotic effect of baicalein, a coumarin flavonone, on human ovarian carcinoma HO-8910 cells, as well as the mechanisms. Methods: HO-8910 cells were treated with esculetin at a series of concentrations for different times. Expression of apoptosis related Bax/Bcl-2, and Caspases proteins in esculetin treated HO-8910 cells were detected by Western blotting. Cell growth and apoptosis were measured by MTT test and flow cytometry in vitro. Results: Cell viability assay showed that esculetin had obvious anti-proliferation effects on HO-8910 cells in a dose- and time-dependent manner. Compared with control group, the group treated with esculetin showed a significant increase in apoptosis rate (P < 0.05, P < 0.01). The results demonstrated that esculetin up-regulated the Bax/Bcl-2 ratio and cleaved Caspase-3, cleaved Caspase-9 expression in a dose-dependent manner. Conclusion: In summary, baicalein exerts anti-growth and induced-apoptosis activity against ovarian cancer HO-8910 cells through activating Caspase and Bcl-2 family proteins, therefore presenting as a promising therapeutic agent for the treatment of ovarian cancer.

Objective To investigate left ventricular(LV) systolic dyssynchrony in heart failure of different etiology which caused respectively by ischemic heart disease and dilated cardiomyopathy and analyse the correlation between the systolic dyssynchrony index(SDI) and the LV ejection fraction(LVEF). Methods Forty-three subjects were divided into two groups. Group A consisted of 17 heart failure patients which caused by ischemic heart disease and group B included 26 heart failure patients which caused by dilated cardiomyopathy. Three-dimensional datum of left ventricle were obtained using real-time three-dimensional echocardiography (RT-3DE) in full volume mode. Post-processing software Qlab was used for advanced analysis. The end-diastolic volume (EDV), end-systolic volume (ESV), LVEF and bull eye graph of seventeen segments were obtained. Standard deviation of time-to-minimal-systolic-volume of 16-LV segments corrected by R-R interval was calculated as SDI of LV. Results There was no statistical difference in age, heart rate, LVEF and EDV between the two groups (P >0.05). SDI of group A was lower than that of group B,but there was no statistical difference between them (P>0.05). Bull eye graph of seventeen segments revealed that the distribution of delayed systolic segments were different between the two groups. SDI of two groups appeared negative correlation with LVEF(r = -0.83, r = -0.71, P-< 0.01). Conclusions LV systolic dyssynchrony existed in heart failure which caused by ischemic heart disease and dilated cardiomyopathy,but the distribution of delayed systolic segments were different between them. SDI increased with worsening LV systolic function.

Objective To assess the value of approximal side angle of carotid atherosclerotic plaques in patients with cerebral infarction by ultrasonography.Methods One hundred and seventy six patients with carotid atherosclerotic plaques were examined with uItrasonography and divided into two groups:cerebral infarction group (n=67)and none cerebral infarction group(n=109).Vessel area and residual lumen area of carotid artery were measured in axial view using linear probe.Area stenosis rate was calculated.The approximal side angle and thickness of plaque were measured respectively.The results of two groups were compared.Results The approximal side angle of plaque of cerebral group was significantly higher than that of none cerebral infarction groups(P<0.05).The sensitivity and specificity for approximal side angle of plaque(cutoff value:13.0°)were 79.1%,71.6%,respectively.There were no significant difference of area stenosis rate and plaque thickness between two groups(P>0.05).Conclusions The approximal side angle of plaque can be regarded as a novel index to assess the stability of plaque.

Objective To establish a quantitative measurement of flow field uniformity of mitral valve in vivo and investigate the correlation between the parameter of flow field uniformity and the degree of mitral stenosis. Methods The flow field uniformity downstream of mitral valve in normal cases and patients with mitral stenosis were studied using vector flow mapping(VFM) technique. Results The flow field uniformity parameter of standard deviation of velocity (Vsd) in patients with mitral valve stenosis was significantly higher than that in control group ( P <0. 05). There was a negative linear correlation between Vsd and effective orifice area(EOA) in patients with mitral valve stenosis (parasternal long-axis: r = - 0. 816, P = 0.000; apical four chamber: r = - 0. 825, P = 0. 000). Conclusions VFM can really reflect the flow field uniformity of normal cases and patients with mitral stenosis.

Objective　To study the occurence, development and regulation of reactive gliosis with astrocyte (Ast) in vitro. Methods　Ast was isolated and cultured in vitro and its model of reactive gliosis was established by scratching the cultured astrocytes. The reactivity and rules of Ast to injury was studied by morphological changes, RT-PCR, immunocytochemistry, in situ hybridization and imaging analysis. Results　After scratching, the astrocytes showed typical features of reactive gliosis, with the hypertrophic cell body, thickened and lengtheded processes, and enhanced glial fibrillary acidic protein (GFAP) staining. In situ hybridization and RT-PCR analysis confirmed that the expression of GFAP mRNA was markedly increased. These changes occurred 1 d after scratching and reached the peak 5 to 7 d after injuring. Conclusion　A model of reactive astrogliosis was successfully established in vitro which showed an active reaction to injury. The characteristics of reactive gliosis parallel that seen in vivo.

Objective To study the prophylactic effect of zolpidem on acute mountain sickness (AMS) after acute highaltitude exposure. Methods A randomized double-blind placebo controlled trial was performed on the plateau. Forty subjects were randomly divided into zolpidem group and placebo group. The general clinical data, heart rate, blood pressure, oxygen saturation, the Pittsburgh Sleep Quality Index (PSQI) scores, AMS scores and physical fitness test of the both groups were collected and assessed on plain and plateau, respectively. ResultsThe PSQI scores were obviously lower and the six-minute walk distance was significantly longer in zolpidem group than those in placebo group (P=0.047 and P=0.009, respectively) after acute high-altitude exposure. AMS incidence was significantly lower in zolpidem group than in placebo group at different time points (P=0.019, 0.014, 0.025 and 0.026, respectively), and the incidence of severe AMS was also significantly lower in zolpidem group than in placebo group at different time points (P=0.047, 0.044, 0.031 and 0.020, respectively). The symptoms of dizziness, weakness and fatigue were significantly lighter in zolpidem group than in placebo group after acute exposure to high-altitude exposure for 20 hours (P<0.05). No significant difference was found in the general physiological findings including, heart rate, blood pressure, oxygen saturation, physical capacity, and the power of hand grip between the 2 groups after acute high-altitude exposure (P>0.05). Conclusion Zolpidem may alleviate AMS symptoms and reduce the incidence of AMS, so it may be promising as a new choice for the prevention of AMS.

Objective To investigate the effects of simulated high-altitude hypoxia on the detection rate and endotoxin level of Porphyromonas gingivalis (Pg) of subgingival bacterial plagues in rabbit periodontitis models. Methods Forty male rabbits were randomly divided into four groups, namely, normoxia control group (group A1), normoxia experimental group (group A2), hypoxia control group (group B1), and hypoxia experimental group (group B2). Each group included 10 rabbits. Periodontitis models was established in groups A2 and B2 combined by ligating both lower central incisors with steel ligature and feeding periodontitis diets, and then the animals were housed in a hypoxia chamber (simulating 5000m altitude, 23h per day). Groups A1 and A2 were raised normal diet in normoxia environment. After eight weeks, the rabbit periodontitis model was evaluated by observing radiographic features of the X-ray films and histopathologic changes under a light microscope. Subgingival plague sample from periodontal pockets on both lower central incisors were collected for isolation, culture and identification of Pg, and for detection of the endotoxin level. Results The histopathologic observation and X-ray examination results showed that the periodontitis of rabbits in group B2 was significantly more severe than that in group A2. The detection rates of Pg in group A1, A2, B1 and B2 was 0%, 50%, 55% and 95% (P<0.05). Pg detection rate and endotoxin level were higher in group B2 (95%, 0.46 0.04EU/ml) than in group A2 (50%, 0.38x 0.02EU/ml, P<0.05). Conclusions The process speed and damage degree of periodontitis in hypoxic environment is higher than that in normoxic environment. Moreover, the hypoxic environment is more suitable in the colonization of Pg with higher endotoxin level in subgingival plague.

Objective To study the synchronization of carotid artery wall motion with atheroscleroticsoft eccentric plaque using velocity vector imaging(ⅤⅥ). Methods Seventy-two patients with carotid artery atherosclerotic soft eccentric plaque were enrolled in this study. Their carotid arteries were examined using Acuson Sequoia 512 instrument respectively.Combined with ECG,two dimensional imaging of short axis view of carotid artery atherosclerotic soft eccentric plaque were recorded and analyzed on-line using ⅤⅥ software. The carotid artery wall of short axis was automatically divided into 6 segments. Time to peak index (TTPI)was calculated respectively. Results The TTPI was significantly higher than that of control group (P＜0.001). A cut-off value＜0.595 of TTPI for assessing the synchronization of carotid artery wall motion had a sensitivity of 93.9%,a specificity of 91.7%,respectively. Conclusions ⅤⅥ provides a new tool to assess the synchronization of arterial wall motion.