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41.
D Michal Freedman Alice Sigurdson Michele Morin Doody Kiyohiko Mabuchi Martha S Linet 《Cancer epidemiology, biomarkers & prevention》2003,12(12):1540-1543
We prospectively investigated whether alcohol intake and smoking affect the risk of basal cell carcinoma (BCC) in subjects from the United States Radiological Technologists (USRT) cohort study. We evaluated 68,371 radiological technologists certified during 1926-1982 who were free of cancer at the time they answered a first questionnaire (1983-1989) and who completed a second questionnaire (1994-1998). The first questionnaire provided baseline information on numerous risk factors, including smoking and alcohol intake, and the second provided self-reported cancer diagnoses. During 698,190 person-years of follow-up, we identified 1,360 cases of BCC: 1,036 in women and 324 in men. Cox proportional hazards regression indicated that the trend in BCC was significantly associated with increased alcohol intake (P for trend = 0.001). Compared with those who reported no alcohol consumption, those who drank <1-2, 3-6, 7-14, and >14 drinks/week had multivariate risks of 1.1 [95% confidence interval (CI), 0.9-1.3], 1.3 (95% CI, 1.1-1.5), 1.4 (95% CI, 1.2-1.7), and 1.0 (95% CI, 0.7-1.6), respectively. We found no clear association between smoking and BCC. This is the second large prospective study to report a significant but nonmonotonic trend in increased risk associated with alcohol consumption. 相似文献
42.
43.
Codistribution of a sensory gating deficit and schizophrenia in multi-affected families. 总被引:6,自引:0,他引:6
M C Waldo G Carey M Myles-Worsley E Cawthra L E Adler H T Nagamoto P Wender W Byerley R Plaetke R Freedman 《Psychiatry research》1991,39(3):257-268
Because the clinical diagnosis of schizophrenia has not generally been an adequate phenotypic marker to detect the genes that convey risk for schizophrenia, efforts have been directed toward the identification of more elementary neuronal dysfunctions in schizophrenic patients and their families. Psychophysiological studies of sensory gating and selective attention suggest that defects in these brain functions are present in schizophrenic patients and some of their relatives. This study examines one of these defects in sensory gating, failure to suppress the P50 evoked response to repeated auditory stimuli. Six pedigrees, chosen because of the presence of large sibships containing several cases of schizophrenia, were studied. A mathematical model was developed to assess the familial association of the P50 defect with schizophrenia. The model preserves the quantitative nature of the data and is suitable for use in a sample with small numbers of pedigrees comprising many individuals. It is thus suitable for the evaluation of putative phenotypes in families to be studied by linkage analysis with polymorphic genetic markers. The results suggest that the P50 defect is familially associated with schizophrenia. 相似文献
44.
免疫层析试验与镜检法、聚合酶链反应诊断疟疾的比较 总被引:3,自引:1,他引:2
目的 评价免疫层析试验 (ICT)诊断疟疾的临床应用价值。方法 以镜检法和聚合酶链反应 (PCR)为对照 ,同时用ICT检测 89份门诊可疑疟疾感染患者的血标本。结果 ICT与镜检法和PCR比较 ,阳性检出符合率分别为 93 .4 %和 86.4 % ;敏感性分别为 90 .16%和 83 .3 3 % ;特异性分别为92 .86%和 91.3 0 %。当虫体密度 >10 0个 / μl时 ,ICT的敏感性为 10 0 % ,虫体密度 <10 0个 / μl时 ,敏感性为 72 .73 % ,虫体密度 <5 0个 / μl时 ,敏感性降低到 66.67%。 结论 ICT适用于疟疾检测的初筛 ,但尚不能完全替代镜检法 相似文献
45.
Auditory evoked potentials were recorded from 163 subjects, aged IS months to 55 years. A conditioning-testing paradigm was used to assess sensory gating. In this paradigm, click stimuli are presented in pairs to the subjects with a 0.5-second intrapair interval. In normal adults, the first stimulus activates or “conditions” sensory gating mechanisms. The strength of these mechanisms is “tested” by the second stimulus, which produces a response whose amplitude is significantly suppressed. This aspect of sensory gating was not reliably observed in our subjects until age 18 years. Younger subjects varied widely in their ability to demonstrate sensory gating. Mean levels of suppression increased during late childhood and adolescence, with no relationship to other changes in evoked potential amplitude and latency. Sensory gating would appear to be a late developing aspect of human sensory physiology. 相似文献
46.
Chronic autoimmune thrombocytopenic purpura (ATP) is a common autoimmune-mediated bleeding disease in which autoantibodies are directed against platelets, resulting in their enhanced Fc-mediated destruction by macrophages in the spleen. While there has been extensive studies relating to the autoantibodies in this autoimmune disorder, relatively few have dealt with cell-mediated immunoregulation of the anti-platelet autoantibody response. Nonetheless, there is accumulating evidence that suggests the production of these anti-platelet autoantibodies is under the influence of several abnormal lymphocyte-mediated mechanisms, i.e. enhanced anti-platelet T helper cell activity with concomitant reduced T suppressor cell activity. This review focuses on these cellular events and presents a working model which attempts to explain their close interrelationships. 相似文献
47.
手术联合中药治疗激素性股骨头缺血性坏死的实验研究 总被引:5,自引:0,他引:5
目的 :初步探讨激素性股骨头缺血性坏死的发病机制 ,观察手术 +中药治疗本病的疗效。方法 :通过对新西兰大白兔联合应用马血清 +甲基强的松龙造模及手术处理 ,对正常组、模型组、手术组、手术 +中药组实验兔的血脂、血液流变学、血生化及股骨头标本切片观察 ,分析比较。结果 :手术 +中药治疗本病的疗效优于单纯保髋手术。结论 :手术 +活血化瘀补肾壮骨方法是股骨头缺血性坏死治疗的合理方法 相似文献
48.
49.
经皮冠状动脉腔内支架置入术治疗冠心病 总被引:2,自引:0,他引:2
目的:评估冠状动脉内支架置入术的效果。方法:回顾性分析1996年2月~2000年2月我院接受冠状动脉内支架置入术的120例病人的治疗效果。结果:在183处病变共置入支架125只。在未经介入性治疗的病变置入支架(De novo stenting)101只,PTCA结果不理想(suboptimal)置入支架19只,2例PTCA并发夹层,濒临闭塞时紧急置入支架(Bail-out stenting)2只,在再狭窄病变置入支架3只。置入支架平均直径3.00±0.69mm,平均长度18.15±10.26mm。手术即刻成功率98.4%,主要并发症率为1.6%((2例AMI)。结论:冠脉内支架置入术是治疗冠心病的一种安全有效的介入性治疗技术,其成功率高,并发症少。 相似文献
50.
J Saunders M Cassidy S B Freedman E A Harley L L Iversen C Kneen A M MacLeod K J Merchant R J Snow R Baker 《Journal of medicinal chemistry》1990,33(4):1128-1138
Recent clinical studies on Alzheimer's patients have implied that only agents displaying high efficacy at the cortical muscarinic receptor have yielded encouraging results. This paper describes the design, synthesis, and biochemical characterization of novel quinuclidine-based muscarinic agonists which can readily penetrate into the central nervous system and which are capable of displaying high efficacy at cortical sites. With use of a biochemical assay capable of measuring receptor affinity and predicting cortical efficacy, it has been discovered that an oxadiazole ring and related heterocycles can function as bioisosteric replacements for the ester moiety found in several known muscarinic ligands. Within this series there exist compounds which span the efficacy range from high-efficacy agonist through partial agonists to antagonists with affinity comparable or superior to that of classical quaternary ammonium ligands. Consistent with recent molecular biology studies, structure-activity trends are interpreted in terms of separate binding sites for agonists and antagonists with H-bonding interactions characterizing agonist behavior and lipophilic binding characterizing antagonist behavior. Thus the aminooxadiazole moiety has structural features which are optimized for an agonist profile. 相似文献