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1.
This paper is a quantitative analysis of the relationship between the chemical structure and the Salmonella mutagenicity of a number of chlorofluorocarbons (CFC). The molecules were characterized by both molecular orbital and physical chemical parameters. The results of the analysis indicated that the CFC mutagenicity is correlated with two parameters: the free energy of binding to biological receptors, and the energy of the highest occupied molecular orbital (HOMO). Since these are the same factors that would favor the cytochrome P-450-catalyzed metabolism, it would appear that the CFC mutagenicity is determined more by the rate of initial activation than by the rate of DNA attack.  相似文献   
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用混合粘合剂碳糊电极测定丁螺环酮   总被引:6,自引:1,他引:5  
用混合粘合剂碳糊电极测定丁螺环酮张正奇,曾鸽鸣,刘传桂,黎艳飞(湖南大学化学化工系,长沙410082)碳糊电极无毒,制作方便,表面更新容易,应用电位范围广,在药物分析中已有应用[1~5]。我们在液体石腊中加入添加剂,组成混合粘合剂,可显著改善电极的检...  相似文献   
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Twenty-five non-menopausal women with uterine myomas were treated with LHRH-analogues for 3-6 months. An average reduction of 40% in uterine volume was observed. One patient refused to complete her therapy, three had no more menses after the interruption of treatment, nine underwent myomectomy within four weeks of their final administration, while in 12 cases hysterectomy was performed. In all cases the decrease in uterine volume induced by the analogue allowed a more limited intervention and prevented excessive blood loss.  相似文献   
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CG Teo 《Oral diseases》2002,8(S2):88-90
Oral hairy leukoplakia (OHL) and Kaposi's sarcoma (KS) are commonly encountered in the HIV-infected patient. A unique feature of OHL is non-cytolytic high level of replication of Epstein–Barr virus (EBV) in the glossal epithelium. The expression of viral-encoded anti-apoptotic proteins concomitant to replicative proteins probably underlies this phenomenon. The question of whether OHL arises from activation of EBV latent in the tongue, or from superinfection by endogenous EBV shed via non-glossal sites or by exogenous EBV remains unresolved. Human herpesvirus 8 (HHV8) is now seen as necessary but not sufficient cause of KS. Expression of HHV8-encoded oncogenic proteins in endothelial cells probably explains the aberrant proliferation of these cells in KS lesions. Studies into why KS is so commonly observed at the palate in HIV-infected patients may provide important clues to its pathogenesis.  相似文献   
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BACKGROUND: The main purpose of this study is to investigate the association of disturbed sleep, chronic physical pain and psychiatric morbidity in people aged 60 years and over. METHODS: A population-based random sample of 7040 household residents aged 60 years and over, was examined in a face-to-face interview. Painful medical conditions were assessed through questions evaluating medical treatment, hospitalizations, and consultations for medical problems. Disturbed sleep was assessed through questions concerning the presence of sleeping problems in the past 4 weeks. RESULTS: The overall prevalence of disturbed sleep is 33.7% (95% CI: 32.5-34.8) and the 6-month prevalence of any chronic pain was 76.2% (95% CI: 74.2-78.2%). A substantial burden of disturbed sleep is associated with the presence of physical pain morbidity, 42.5% for back pain to 49.7% for headaches. The prevalence of pain among persons with disturbed sleep ranges from 25.8% for gastrointestinal pain to 54.6% for joint pain. The presence of comorbid pain and disturbed sleep has an important disability impact as assessed by socioecomomic/professional data, health care utilization, self-rated health and physical activity. In logistic regression models, headaches, psychiatric morbidity, rural origin, Caucasians, self-rated health and number of chronic pain conditions were significantly associated with disturbed sleep after controlling for demographic variables and comorbidities. Age has a negative effect on sleep complaints. CONCLUSIONS: Disturbed sleep is highly comorbid with other pain conditions particularly headaches and psychiatric morbidity in later life. The combination of pain and disturbed sleep leads to important role disability and increased utilization of medical services.  相似文献   
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In 239 torquetenovirus-positive people, multiple-genogroup infections were common and associated with higher viral loads than would be expected from simple additive effects. The latter observation was restricted to the infections which included both genogroups 1 and 3, pointing to the possible existence of some kind of infection facilitation between these genogroups.  相似文献   
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