A wide range of computer and internet applications impact on people's lifestyles andways of thinking profoundly, Internet acculturation is an important research issue in the information age.By the literature review,this paper summed up the themes of medical students' internet acculturation:in-ternet addiction disorder research,internet morality anomie research and internet learning adaptation re-search.Some suggestions for future research were put forward at last.

Objective To study the feasibility of reducing radiation dose in aorto-iliac and lower extremity arteries CT angiography (CTA) with low tube voltage (100 kV) and automatic tube current modulation(ATCM).Methods Totally 61 patients requiting aorto-iliac and lower extremity arteries CTA for clinical reasons were prospectively enrolled in study.The patients were randomly assigned to 3 groups:Group A(120 kV),Group B (100 kV) and Group C (100 kV with automatic tube current modulation).Both quantitative and qualitative analysis were included in this research.Group C was divided into obese group(BMI≥ 24.9 kg/m2) and normal group(BMI ＜ 24.9 kg/m2).The radiation doses were analyzed respectively among two groups.Results The subjective evaluations of image quality for axial,MIP and VR were good.There were no significant differences among group A,B and C in SNR and CNR (P ＞0.05).The effective dose of group A,B and C was 8.20 mSv,5.36 mSv,and was 7.48 mSv,respectively Group B was 34.6％ less than group A.Group C was 39.5％ more than group B,and there was no significant differences between group A and C (P ＞ 0.05).The effective dose of group C1 was 7.11mSv,group C2 was 9.69 mSv,the E with group C1 were significantly less than group C2 (t =-3.163,P ＜0.05),the effective dose of group C1 was 13.3％ less than group A (Z =-2.822,P ＜ 0.05),but the group C2 was more than group A (P ＞ 0.05) and group B (Z =-3.426,P ＜ 0.05).Conclusions Lowkilovoltage (100 kV) CT scanning protocol is feasible in multi-detector CT angiography for aortoiliac and lower extremity arteries.Automatic low tube voltage (100 kV) with automatic tube current modulation (ATCM) scanning protocol can be used for someone with BMI less than 24.9 kg/m2.

Objective:To examine the pathological change and intima thickness of thoracic aorta, detect the serum concentration of hypoxia-inducible factor-1α(HIF-1α), oxidized LDL (ox-LDL), and pentraxin 3 (PTX3) in the rat model of chronic intermittent hypoxia (CIH), and to determine the effect of CIH on endarterium injury and its possible pathway.Methods:Twenty-four male Sprague-Dawley (SD) rats were divided into 4 groups:a CIH+N-acetylcysteine (NAC) group, a CIH+normal saline (NS) group, a CIH control group and a control group. CIH rats were subjected to alternating cycles of hypoxia (6%-8%O2 in N2 for 20-25 s) and normoxia (21%O2 in N2 for 2 min) every 180 s for 7 h/d. Rats in the control group were not treated. Rats in the CIH+NAC group were treated with NAC [800 mL/(kg.d)] intraperitoneal injection, and rats in the CIH+NS group were treated with NS [5 mL/(kg.d)] intraperitoneal injection. Atfer 42 day treatment, the rats were sacriifced, blood taken, and thoracic aorta cut off. hTe serum concentration of HIF-1α, ox-LDL, and PTX3 were detected by ELISA. hTe thickness of intima was taken by computer digital image analysis. Results:Vascular endothelial cell injury and detachment were found in the thoracic aorta in the CIH and the CIH+NS group. The intima in the CIH and the CIH+NS group was thicker than that in the control and the CIH+NAC group (P<0.001). The serum concentration of HIF-1α, ox-LDL, and PTX3 in the CIH and the CIH+NS group was higher than that in the control and the CIH+NAC group (P<0.001). The serum concentration of HIF-1α, ox-LDL, and PTX3 was pairwise positive correlation, and the serum concentration of ox-LDL and PTX3 was positively correlated with the thickness of intina (P<0.001). Conclusion:hTe vascular endothelial cell injury and endarterium thickening can be induced by CIH. It is an important pathway that CIH activates oxidative stress and elevates the levels of HIF-1α, ox-LDL, and PTX3.

Objective To investigate the feasibility of the low tube voltage setting and personalized contrast agent application in 64-row multi-slice spiral CT pulmonary angiography.Methods Ninety patients with high risk of pulmonary artery embolism were sequentially enrolled in the study and divided into 3 groups employing completely randomized design: (1) Regular group included 30 patients using 120 kV and fixed dose of 70 ml contrast agent, (2)Another 30 patients were in 120 kV group, using 120 kV and the contrast amount was determined according to the patient weight (1.0 ml/kg), (3) The remaining 30 patients were included in 100 kV group, using 100 kV and the contrast amount was also determined according to the patient weight(1.0 ml/kg).Administration of contrast agent was completed within 20 seconds for all the patients, followed by 20 ml of saline.The objective and subjective indexes for assessing CT image quality, CT dose index volume (CTDIvol) and effective received dose (ERD) were compared between 120 kV group and 100 kV group; then the contrast media volume, injection rate, objective CT image indexes and subjective indexes for image quality was compared between the 100 kV group and regular group.The variance analysis and post hoc test were employed for the statistical analysis.Results Compared with 120 kV group(3.4± 0.7), the image quality of 100 kV group(5.2±1.8)had higher noise(52.9%), but subjective index for the image quality demonstrated no differences(q=0.272 ,P=0.063)in mediastinum window while CTDIvol and ERD decreased for 34.9%[(9.5±0.0) vs (14.6±0.0) mGy]and 36.8%[(3.8±0.6) vs (2.4± 0.4) mSv].The mean CT values on pulmonary artery of 100 kV group[(269.2±54.7) HU]were 13.4% (31.8/237.4) higher than the 120 kV group[(237.4±62.9) HU], but there was no statistical differences eornpared to normal group(q=0.172,P=0.260).Conclusion Using low kV setting (100 kV) to reduce radiation dose is proved to be effective and feasible in 64-MSCT pulmonary angiography.Personalized contrast agent injection has clinical application value for specific patient group.

s: The onset of Crohn’s disease (CD) is the interaction of environment, heredity, infection, immune and other factors. It is also closely related to abnormal immune functions. Without special treatment, CD is identified as a modern refractory disease. By syndrome differentiation and treatment, traditional Chinese medicine (TCM) can effectively relieve disease conditions, improve the quality of life and reduce side effects of modern medication. The core compatibility ofBai-Zhu andFu-Ling can reinforce spleen-qi and dispel dampness, which met the common pathogenesis of CD. Therefore, the combination is comprehensively used in the compound prescription. Our previous study found thatBai-Zhu Fu-Ling decoctioncan reduce the vasoactive intestinal peptide (VIP) of animal model of spleen-qi deficiency, downregulate VIP receptors, decrease the affinity of VIP receptors and improve animal model’s sIgA. To further clarify the effects about neurotransmitters and their correlation with the immune system in the pathogenesis of CD and the intervention mechanism treated by different proportional compatibility ofBai-Zhu Fu-Ling decoction, we studied influences of the decoction on related transmitters of nerve- immune network and functions of receptors, as well as cytokine secretion and signal transduction of TLR4-NF-κB. Our studies can provide references and foundations to further explore TCM treatment of CD.

Objective: To investigate the antiviral effect of hepatitis B virus (HBV) S gene-specific anti-gene locked nucleic acid (LNA) in transgenic mice. Methods: A total of 30 HBV transgenic mice were randomly divided into blank control group (5% glucose + liposome), unrelated sequence control group, lamivudine control group, antisense LNA control group, and anti-gene LNA group, with 6 mice in each group. The mice in the lamivudine group were given lamivudine by gavage, and LNA was injected via the caudal vein. Quantitative real-time PCR was used to measure serum HBV DNA, ELISA was used to measure serum HBsAg, RT-PCR was used to measure HBV S mRNA level in the liver, and immunohistochemistry was used to measure the level of HBsAg in hepatocytes. Results: At 3, 5, and 7 days after treatment, there were significant changes in the inhibition rates of HBV DNA (37.18%, 50.27%, and 61.46%, respectively) and HBsAg (30.17%, 44.00%, and 57.76%, respectively) achieved by anti-gene LNA (P < 0.01), and there were significant differences between the anti-gene LNA group and the other four control groups (P < 0.05). In the anti-gene LNA group, the relative mRNA expression of HBV S gene was 0.33 and the percentage of HBsAg-positive hepatocytes was 31%, which were significantly different from these two indices in the control groups (P < 0.05). There were no abnormal changes in liver/renal biochemical parameters and HE staining results. Conclusion Anti-gene LNA targeting at HBV S gene has a strong antiviral effect in transgenic mice, which provides theoretical and experimental bases for gene therapy for HBV.

Objective:To analyze the trend of maternal mortality ratio (MMR) and death causes in Tianjin from 2011 to 2020 and to guide the management of maternal health.Methods:All the reviews data of 89 maternal death cases in Tianjin from 2011 to 2020 were retrospectively collected to analyze the trend of MMR, rank order of death causes, and death review results using Chi-square test. Results:(1) The average MMR in Tianjin was 7.97/100 000 during the study period, showing an overall fluctuating decline. The highest MMR was 12.61/100 000 in 2014 and the lowest was 3.85/100 000 in 2019. (2) Among the dead pregnant women and parturients, non-registered residents had higher proportion of women with advanced age, no steady occupation/unemployment, below junior college education, multipara, or without maternal health manual compared with the registered residents [33.33% (8/24) vs 20.00% (13/65), χ2=46.18; 100.00%(24/24) vs 69.23%(45/65), χ2=9.53; 87.50% (21/24) vs 64.62% (42/65), χ2=4.44; 79.17% (19/24) vs 44.62% (29/65), χ2=8.42; 75.00%(18/24) vs 13.85% (9/65), χ2=31.02; all P<0.05]. (3) Direct obstetric factors and indirect factors that caused death were accounted for 57.30% (51/89) and 42.70% (38/89). The top five death causes were postpartum hemorrhage, hypertensive disease during pregnancy, sudden death, venous thrombosis and pulmonary embolism, and amniotic fluid embolism. (4) In terms of the maternal death review results, 39.33% (35/89) of maternal deaths were avoidable, among which 94.29% (33/35) were caused by direct obstetric factors and 5.71% (2/35) were indirect. (5) The main influencing factors of avoidable death causes were knowledge and skills inadequacy in the health care system (62.86%, 22/35), of which 86.36% (19/22) happened in health facilities at and below the district/county level. Conclusion:It is suggested to strengthen the medical care of health facilities at and below the district/county level and the maternal health management of the non-permanent residents to ensure maternal and infant safety and to further reduce the MMR.

Objective:To investigate the causal relationship between trimethylamine N-oxide (TMAO) and its precursors (betaine, carnitine, and choline) and pancreatic diseases based on the Mendelian randomization (MR) method.Methods:Genome-wide association study data of TMAO, betaine, carnitine, choline, acute pancreatitis (AP), chronic pancreatitis (CP), pancreatic cancer (PC), and circulating immune cell characteristics (white blood cell, lymphocyte, monocyte, neutrophil, eosinophil and basophil) were collected. According to the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE)-MR reporting guidelines, the available genetic variants [single nucleotide polymorphism (SNP)] were strictly screened. The causal relationship between exposure (TMAO and its precursors) and outcomes (pancreatic diseases and circulating immune cell characteristics) was evaluated using inverse variance weighting (IVW), MR-Egger regression and weighted median. The reliability of the results was evaluated by sensitivity analysis based on MR-Egger regression, MR-PRESSO, Cochrane's Q test and leave-one-out method. Results:A total of 36 SNP associated with TMAO and its precursors were included. Five of these were associated with TMAO, 13 with betaine, 12 with carnitine, and 6 with choline. ① MR analysis showed that TMAO may increase the risk of AP [odds ratio ( OR) = 1.100, 95% confidence interval (95% CI) was 1.008-1.200, P = 0.032], and choline may reduce the risk of alcoholic acute pancreatitis (AAP; OR = 0.743, 95% CI was 0.585-0.944, P = 0.015). The analysis results of MR-Egger regression and weighted median were consistent with the IVW results. There is no evidence to support a causal relationship between TMAO and its precursors and the risk of CP and PC. Sensitivity analysis indicated that SNP analyzed by MR showed no heterogeneity and low pleiotropy. The leave-one-out method analysis determined that after excluding any SNP, the effect intervals of the remaining SNP on the results were similar to the overall effect intervals, which suggested the robustness of MR results. ② There was a positive causal relationship between plasma TMAO level and circulating monocyte count ( OR = 1.017, 95% CI was 1.000*-1.034, P = 0.048, * represented that the data was obtained by correcting to 3 decimal places from 1.000 1). The causal effect obtained by MR-Egger regression and weighted median analysis was consistent with the results of IVW. Sensitivity analysis illustrated SNP analyzed by MR showed no heterogeneity and pleiotropy. The leave-one-out method analysis determined that after excluding any SNP, the effect intervals of the remaining SNP on the results were similar to the overall effect intervals, which suggested the robustness of MR results. Conclusion:TMAO and choline may change the risk of AP, and TMAO may contribute to the increase of circulating monocyte count in AP.

ObjectiveTo analyze the prevalence and influencing factors of mental health problems among hypertensive patients in Ya'an city five years after the Lushan earthquake， so as to provide references for promoting the mental health of hypertensive patients in earthquake-stricken areas. MethodsStratified random cluster sampling method was adopted to select 800 hypertensive patients in Ya'an city in December 2018. The general information of patients were collected via a self-designed questionnaire， and their mental health problems were assessed via the 12-item General Health Questionnaire （GHQ-12）.Then Logistic regression analysis was applied to explore the influencing factors. ResultA total of 744 valid questionnaires （93.00%） were obtained， and mental health problems were detected in 79 cases （10.62%）. Univariate analysis denoted that the detection rate of mental health problems yielded statistical difference among patients of different marital status （P<0.01）， family per capita monthly income （P=0.012） and social assistance recipients （χ²=25.194， P<0.01）. Logistic regression analysis indicated that the unmarried/separated/divorced/widowed status （OR=3.879， P=0.015） and social assistance recipients （OR=4.705， P<0.01） were risk factors for mental health problems among hypertensive patients. ConclusionThe detection rate of mental health problems is low among hypertensive patients in Ya'an city， while the unmarried/separated/divorced/widowed and social assistance recipients may suffer more serious mental health problems.

ObjectiveTo investigate the prevalence and characteristics of depressive symptoms among urban elderly six years after Lushan earthquake in Ya'an， so as to provide references for the mental health interventions for elderly following catastrophic stressful life events. MethodsFrom March to April 2019， a multi-stage stratified cluster random sampling method was adopted to enroll 885 urban elderly people aged 60 and above in Ya'an. A self-compiled questionnaire was used to collect the general demographic information， health-related and disaster-related information， meantime， the elderly was assessed using Geriatric Depression Scale （GDS-30）. Thereafter， univariate and multivariate Logistic regression were applied to explore the influencing factors of depressive symptoms in urban elderly. ResultsA total of 783 valid questionnaires were collected， with a questionnaires response rate of 88.47%. Depressive symptoms were detected in 161 cases （20.56%）. The prevalence of depression showed statistical differences among the elderly of different gender， age， marital status， family relationship， monthly per capita household income， physical exercise status， health status， self-care ability， sleep status and disaster-affected degree （P<0.05 or 0.01）. Logistic regression analysis showed that the urban elderly of the female gender （OR=1.552， P=0.040）， monthly per capita household income of 2000~3000 yuan （OR=6.982， P<0.01）， monthly per capita household income≤2000 yuan （OR=6.857， P<0.01）， lack of physical exercise （OR=1.693， P<0.01）， being less capable of self-care （OR=3.838， P<0.01）， being incapable of self-care （OR=8.547， P<0.01）， complicating multiple curable diseases （OR=4.892， P<0.01） and complicating refractory chronic diseases （OR=5.657， P=0.031） were at high risk of depressive symptoms. The risk of depressive symptoms among the divorced or widowed elderly was greater than that among married elderly （OR=0.063， P<0.01）. ConclusionThe prevalence of depressive symptoms is relatively high among the urban elderly six years after Lushan earthquake in Ya'an， moreover， female gender， low monthly per capita household income， lack of physical exercise， being incapable of self-care and poor health status are risk factors affecting the depressive symptom， while being married is a protective factor.