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Tot S  Yazici K  Yazici A  Metin O  Bal N  Erdem P 《Public health》2004,118(8):588-593
The objective of this study was to determine the effects of psychosocial factors such as peer group, family and academic self-perception on smoking, alcohol and substance use by adolescents living in Mersin, Turkey. The study included a total of 3282 students from the sixth and tenth grades and college. The number of participating students required from each school was obtained through stratification, and by weighing the enrolled student population in each subgroup. The final sample was derived using a simple random sampling technique. A 45-item self-administered questionnaire was used. The questionnaire included questions about socio-demographic characteristics and lifetime and current (i.e. within the past month) use of cigarettes, alcohol, cannabis, inhalants and other illicit drugs (heroin, cocaine, sedative-hypnotic drugs, etc.). This study found that: (1) higher socio-economic status of the family increased the likelihood of smoking and alcohol use in adolescents; (2) the prevalence of alcohol use was higher in adolescents whose mothers had a higher educational level and whose mothers and fathers drank alcohol; (3) there was a significant association between substance use and having a peer who used a substance; and (4) the prevalence of smoking was significantly higher in students who perceived their academic performance to be poor. Understanding the role and importance of psychosocial factors associated with smoking, alcohol and substance use will be crucial to develop preventive measures for adolescents.  相似文献   
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The present study was carried out to evaluate the effects of 1alpha,25-dihydroxyvitamin D3 (VD) on chromosomal aberrations induced by doxorubicin (DXR). Wistar rats were divided into eight experimental groups of five animals each. Control group animals were treated with i.p. distilled water. The animals in three VD groups were given only VD for 4, 6 or 8 weeks. In the DXR groups the animals were given only DXR. In the combination groups VD doses were given for 4, 6 or 8 weeks for each group and DXR was injected 24 h before sacrificing the rats. DXR (50 mg/100 g b.w.) was injected intraperitoneally and VD by gavage 3 microg/kg/day twice weekly. Animals treated with both VD and DXR showed a low frequency of chromosomal aberrations and abnormal metaphases when compared with animals treated with DXR alone (p < 0.0001). The numbers of both chromosomal aberrations and abnormal metaphases were similar in weeks 6 and 8 (p > 0.05) and lower than those in week 4 for the VD groups (p < 0.0001). Under the present experimental conditions, the efficiency of VD in protecting cells against DXR-induced chromosome damage was found to be dose dependent. The protective effects of VD on chromosome aberrations induced by DXR are discussed in the light of literature data.  相似文献   
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Cardiopulmonary bypass (CPB) is one of the major tools of cardiac surgery. However, no clear data are available for the ideal value of sweep gas flow to oxygenator during CPB. The aim of this study was to determine the best value for sweep gas flow during CPB. Thirty patients undergoing isolated CABG were randomly and equally allocated into three groups. Sweep gas flow to oxygenator was kept at 1.35 l/min/m2 in group 1, 1.60 l/min/m2 in group 2, and 2.0 l/min/m2 in group 3. All patients were operated on under the same anaesthetic regime and surgical techniques. Samples for blood gas analysis were collected at T1: before CPB; T2: 5 min after the initiation of CPB; T3: just before rewarning; and T4: at the end of rewarming. Five minutes after the initiation of CPB (T2), pCO2 decreased significantly in groups 2 and 3 compared to group 1 (p < 0.02). With the addition of hypothermia (T3), the changes in the pH and pCO2 became more profound and, in this period, the levels in group 3 patients outranged the physiologic limits, with pCO2 and pH values being 28 +/- 3 mmHg and 7.50 +/- 0.04, respectively. At the end of the rewarming period (T4), in spite of increased carbon dioxide production, pCO2 values were below the physiologic limits in groups 2 and 3. We conclude that sweep gas flow to the oxygenator should be kept between 1.35 and 1.60 l/min/m2 during CPB to avoid hypocapnia, which results in alkalosis and has hazardous effects on lung mechanics, cerebral blood flow, and the cardiovascular system.  相似文献   
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The aim of this study was to investigate the effects of stent carbon coating on inflammatory response. The authors serially measured plasma concentrations of C-reactive protein (CRP), fibrinogen, and several cytokines (tumor necrosis factor, interleukin [IL]-1-beta, IL-6, and IL-8) in patients with single-vessel coronary stenosis who underwent primary stent implantation. None of the subjects had inflammatory or infectious disease at the time of the procedure. Forty-six patients (38 males; mean age 55 +/-9 years) were studied. Blood samples were collected before and at 2, 4, 6, 24, and 48 hours after stent implantation. Patients were randomly assigned 1 of 2 different stent types, an uncoated MAC (AMG Raesfeld-Erle, Germany) (UC-MAC) or a carbon-coated MAC (CC-MAC) stent. Implantations were performed without predilatation, and stents were deployed at a maximum pressure of 6 atmospheres for 90 seconds. Of the 46 patients, 14 had stable, 27 had unstable, and 5 had atypical angina. According to ACC/AHA classification, 35 lesions (76.1%) were type A, 10 (21.7%) were type B, and 1 (2.2%) was type C. Single stenosis of 28 left anterior descending, 12 circumflex, and 6 right coronary arteries were treated. Serum IL-6 increased in both the UC-MAC and CC-MAC groups, with concentrations significantly elevated above baseline at 6 hours, and then decreasing after 24 hours (baseline, 6-hour, and 24-hour values = 3.1 +/-2.3, 5.7 +/-3.8, and 6.3 +/-4.6 pg/mL, respectively, in UC-MAC; 3.7 +/-2.6, 6.2 +/-6.0, and 4.6 +/-3.7 pg/mL, respectively, in CC-MAC [p=0.002]). Plasma fibrinogen, CRP, and leukocyte concentrations also increased in both groups over the 24 hours (p < 0.05). The elevations of IL-6, CRP, and fibrinogen were similar in the 2 groups. The percent increases in IL-6, fibrinogen, and CRP were not associated with stent length, size, or clinical presentation (all p > 0.05). The results showed that stent implantation increases plasma IL-6, fibrinogen, and CRP concentrations, but carbon coating of the stent does not seem to affect this inflammatory response.  相似文献   
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OBJECTIVE: This article describes the MR imaging features of carcinosarcoma of the urinary bladder with clinical presentation and pathologic correlation in three adults. CONCLUSION: Carcinosarcoma of the urinary bladder is a rare and aggressive tumor that has a clinical presentation similar to that of transitional cell carcinoma of the bladder. Dynamic gadolinium-enhanced MR imaging features are discussed.  相似文献   
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Despite the effectiveness of clomipramine and selective serotonin reuptake inhibitors (SSRIs) in the treatment of obsessive-compulsive disorder (OCD), 40% to 60% of patients who receive an adequate treatment with these agents have significant persisting symptoms. Newer atypical antipsychotic drugs showed efficacy as augmenting agents in patients with OCD resistant to serotonin reuptake inhibitors (SRIs). The objective of this study was to evaluate the efficacy and safety of amisulpiride augmentation in treatment resistant OCD. A total of 20 patients diagnosed with OCD according to DSM-IV criteria and having a history of resistance to treatment with SRIs were included in the study. Amisulpiride 200 mg/day was added to ongoing SRI treatment and titrated up to 600 mg/day in flexible doses. The mean amisulpiride dose was 325 +/- 106 mg/day. The patients were assessed with the Yale-Brown obsessive-compulsive scale (Y-BOCS) at baseline and at week 12 of amisulpiride treatment. Side effects were monitored by the UKU side effect rating scale. The reduction in Y-BOCS scores between the baseline (26.7 +/- 6.3) and the end of the treatment (12.5 +/- 2.8) was statistically significant (p=0.0001). The most commonly observed side effects included weight gain (14 patients, 70%), mild sedation (13 patients, 65%) and asthenia (7 patients, 35%). This study has several limitations and, hence, the results are preliminary and require confirmation in a randomized controlled trial. In conclusion, this study suggests that amisulpiride may be a promising option as an augmentation strategy in treatment resistant OCD.  相似文献   
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