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151.
Hepatitis A is an important infectious disease in Israel. The high incidence of hepatitis A, the declining prevalence of antibodies against hepatitis A virus throughout the past decade, and the availability of an active immunization for hepatitis A have engendered the identification of occupations in which workers are at increased risk of acquiring the disease. A prevalence study for hepatitis A antibodies was conducted during the first half of 1998 in a random sample of 37 day-care centers in different parts of Israel. A short interview was conducted, and serum samples were then collected from each worker. The control group comprised a sample of factory workers, blood donors, and women in maternity wards. Ninety percent (402 of 446) of the day-care workers had antibodies to hepatitis A. In a logistic-regression analysis, seropositivity was associated with increased age, minimal education, and lack of military service. When the authors compared a subsample of workers aged 18–40 yr with the control group, seropositivity was associated with the following: birth in Israel, duration of residence in Israel, very minimal education, military service, and employment in a day-care center. These results, together with earlier reports, indicate that day-care workers are at high risk of occupational exposure to hepatitis A. These results may imply that seronegative workers have a 2-fold chance of acquiring hepatitis A. Appropriate preventive measures should be considered, and active immunization of susceptible workers should be undertaken.  相似文献   
152.
Objective: In the present study, we used a multilevel approach to investigate the role of maternal country of birth (MCOB) in predicting adolescent use of psychotropic medication in Sweden.

Design: Using the Swedish Medical Birth Register we identified all 428,314 adolescents born between 1987 and 1990 and who were residing in Sweden in the year they turned 18. We applied multilevel logistic regression analysis with adolescents (level 1) nested within MCOBs (level 2). Measures of association (odds ratio) and measures of variance (intra-class correlation (ICC)) were calculated, as well as the discriminatory accuracy by calculating the area under the Receiver Operator Characteristic (AU-ROC) curve.

Results: In comparison with adolescents with Swedish-born mothers, adolescents with mothers born in upper-middle, lower-middle and low-income countries were less likely to use psychotropic medication. However, the variance between MCOBs was small (ICC = 2.5 in the final model) relative to the variation within MCOBs. This was confirmed by an AU-ROC value of 0.598.

Conclusions: Even though we found associations between MCOB and adolescent use of psychotropic medication, the small ICC and AU-ROC indicate that MCOB appears to be an inaccurate context for discriminating adolescent use of psychotropic medication in Sweden.  相似文献   

153.
154.
In continuation of our previous studies on orbitofrontal cortex function in obsessive compulsive disorder (OCD) we studied a group of OCD patients with schizophrenia in comparison with a group of schizophrenia patients. In order to test orbitofrontal cortex function we again used an alternation learning task. We found no difference between the two groups in the performance of this task. The relationship between severity of OC symptoms and alternation learning was curvilinear. Thus, in the low range of symptom severity the correlation between alternation learning and symptom severity was negative, while in the high range it was positive. The positive correlation in the severely affected patients is essentially the same as that found in severe "pure" OCD patients, which we have previously reported. We conclude that the data indicate independent orbitofrontal cortex function in OCD, irrespective of comorbidity.  相似文献   
155.
AIMS: h-TERT is the keystone gene in controlling telomerase expression under the modulation of many associated genes. Our study was designed to observe the concordant expression of the telomerase associated genes in NSCLC (non-small cell lung cancer). METHODS: Between January 1999 and December 1999, 78 NSCLC patients were studied. The telomerase activity was measured by TRAP (telomeric repeat amplification protocol) assay, and the associated genes (h-TERT, h-TERC, TP1, c-Myc, TRF1, and TRF2) were detected using RT-PCR method. RESULTS: Positive telomerase activity was identified in 47 (60.3%) patients. Expression of the h-TERT, h-TERC, TP1, c-Myc, TRF1 and TRF2 genes were observed in 66.6, 92.3, 100.0, 91.0, 74.4 and 83.3% of the tumor tissues, respectively. Higher expression of the telomerase activity was found in advanced T-status (p=0.0265), and late TNM stages (p=0.0497) patients. In addition to the tumor tissue itself (p<0.0001), higher telomerase expression rates were observed in positive h-TERT (p<0.0001), and positive TRF1 (p=0.003) tumor tissues compared to their normal counterparts. Furthermore, h-TERT expression was closely related to the TRF1 (p=0.003), TRF2 (p=0.024), and c-Myc (p=0.042) expression. CONCLUSIONS: Our data demonstrate that expression of the telomerase activity can be observed in the majority of NSCLC tumor tissues, and is also closely related to the T-status and TNM stage of the tumor. h-TERT expression and subsequent telomerase activation leads to telomere repair under modulation by the TRF1, TRF2 and c-Myc genes.  相似文献   
156.
目的:研究腺嘌呤核苷酸转位酶1(ANT1)在亚硒酸钠抑制脑胶质瘤生长中的作用机制.方法:将不同浓度的亚硒酸钠(0.5、1.0、2.0、4.0μmol/L)侵染人脑胶质瘤细胞SHG44,MTT比色法检测亚硒酸钠对SHG44的增殖的影响;PCR法检测ANT1的表达;提取细胞线粒体后通过观察线粒体的荧光强度,检测SHG44的线粒体膜电位和膜通道开放程度.结果:亚硒酸钠对人脑胶质瘤细胞具有明显的抑制作用,2.0及4.0 μmol/L染硒组差异均有统计学意义(P<0.05),ANT1的表达在各染硒组均出现显著性增加(P<0.05);线粒体膜电位在2.0及4.0μmol/L染硒组显著降低(P<0.05),线粒体膜通道转运孔开放程度在1.0、2.0及4.0μmol/L组显著增高(P<0.05).结论:亚硒酸钠能抑制人脑胶质瘤细胞SHG44地生长,并伴随线粒体膜电位降低和线粒体膜通道转运孔开放程度增加,ANT1可能参与了其作用机制.  相似文献   
157.
158.
食管曲张静脉压力测定是预测食管曲张静脉出血的最主要因素 ,食管曲张静脉的压力可在内镜下测定。 Palm er于195 1年首次报道静脉内测压 ,1982年瑞士学者 Monismann利用呼吸压力测定原理进行食管曲张静脉血管外测压。该方法不断改进 ,无创测压与直接穿刺测压的比较研究发现两者有极好的直线相关关系。目前 ,无创性食管曲张静脉测压研究仍处于实验室阶段 ,尚未获得公认 ,其原因在于难以消除血管壁张力对贴壁测压的影响  相似文献   
159.
OBJECTIVES: Current criteria of the N-category in the TNM staging system for carcinoma of the esophagus needs further subgrouping due to its simplicity in mixing together patients with different prognosis. METHOD: A retrospective cohort study of 186 patients (176 men and ten women; mean age, 59.9 years) with squamous cell carcinoma (SCC) of the thoracic esophagus who underwent esophagectomy followed by two-field lymphadenectomy and cervical lymph node sampling between 1992 and 1999 was conducted. A proposed N-category which involved dividing the nodal status into N0 (no nodal involvement), N1 (< or =4 nodes or < or =20% nodal involvement), and N2 (>4 nodes, or >20%, or non-regional nodal involvement) subgroups was used for survival analysis. RESULTS: The overall 5-year cumulative survival rate was 27%. Lymph node metastases were identified in 101 (54.3%) patients. Cumulative survival rates were 46% at 4 years in the N0 group and 21% at 4 years in the N1 group, whereas no patients in N2 group survived longer than 3 years (P<0.01). A multivariable analysis revealed that independent prognostic factors included the depth of tumor invasion (P<0.01), nodal involvement (P<0.01), and organ metastasis (P<0.01). CONCLUSION: In addition to the location of nodes, the extent of nodal involvement in SCC of the thoracic esophagus also plays an important role in prognosis prediction.  相似文献   
160.
Topical anesthetics are recommended when electroretinograms (ERGs) are recorded using contact lens electrodes. However, these drugs act by blocking voltage-gated Na+ channels. Since such channels have been located in both the inner and outer retina of many species, topical anesthesia could affect the ERG recordings in these subjects. The purpose of this study was to evaluate the effects of oxybuprocaine, a commonly used ester local anesthetic, on the rat ERG. Full-field scotopic and pattern ERGs (PERGs) were recorded successively from both eyes of seven rats. One eye was randomly treated with oxybuprocaine 15 min prior to recording. In 10 rats unilateral full-field photopic ERG recordings were conducted prior to, and 15 min after, treatment. B-wave amplitude ratios of the experimental/control eyes were 1.13, 1.30, and 1.35 for the three intensities used to record scotopic ERG responses, and 1.04 for the photopic ERG responses. PERG amplitude ratios of the experimental/control eyes were 1.10, 1.21, 1.21, 1.24, and 1.26 for the five patterns used. Treatment had no significant negative effect on signal amplitude or implicit time of the full-field ERG or PERG. In fact, amplitudes of signals from treated eyes tended to be (insignificantly) higher, though this might reflect better position of the active electrode rather than a biological effect. We conclude that oxybuprocaine has no negative effect on the rat ERG.  相似文献   
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