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31.
As a part of our ongoing study on Alzheimer's disease (AD) in elderly African Americans, we obtained clinical assessment and apolipoprotein E (ApoE) genotype data on 288 individuals (including 60 with AD). The ApoE σ4 allele frequency was significantly increased in AD patients compared with controls. The age-adjusted odds ratio (OR) for AD in σ4 homozygotes was 4.83 (95% confidence interval [CI], 1.71–13.64) compared with the σ3/σ3 genotype, but the OR for AD with the σ3/σ4 genotype did not reach significance (1.20; 95% CI, 0.58–2.45). These findings suggest that the association between ApoE σ4 and AD is weaker in African Americans than in whites.  相似文献   
32.
四叠体池蛛网膜囊肿   总被引:2,自引:0,他引:2  
目的:探讨四叠体池蛛网膜囊肿的临床特征和治疗方法。方法:对11例四叠体池蛛网膜囊肿进行了回顾性总结分析。所采用的手术方法有:①脑室分流手术;②囊肿-腹腔分流术;③囊肿切除;④囊肿切除加囊肿-脑池分流术,或囊肿部分切除(即囊肿开窗术),或囊肿切除加脑室-脑池分流术。结果:其主要临床表现以颅内压增高症和中线综合征为主。上述方法中单纯囊肿壁切除只能使部分病人的病情缓解,脑室分流或囊肿切除加脑室分流手术的疗效较好。结论:四叠体区蛛网膜囊肿常合并梗阻性脑积水,单纯囊肿切除不能解除多数病人的梗阻性脑积水。作者根据囊肿是否与蛛网膜下腔相通提出:对交通性蛛网膜囊肿采用单纯性脑室分流术,对非交通性者采用囊肿切除加脑室分流手术的治疗方法。  相似文献   
33.
Objective: To examine the relationship between ambient lead levels and blood lead levels and to explore the modifiers of the relationship between ambient lead and blood lead. Method: A cross-sectional study was conducted in two lead battery factories. Blood lead level and ambient lead concentration were measured for each participant concurrently. A structured questionnaire was administered to collect sociodemographic characteristics and occupational history. Design: Biological and personal environmental measurements of 219 lead-exposed workers were analyzed by both simple and multiple linear regression. A regression model was selected for interpretation. Results: A high correlation (r=0.62) between ambient lead (PbA) and blood lead (PbB) was observed. In addition, numerous factors, including age, sex, alcohol consumption, personal hygiene practice and type of lead exposure, were also found to influence blood lead levels. Although PbB was highly correlated with PbA, blood lead level may not be effectively lowered by reducing ambient lead level. Based on the regression coefficients, improvement of hygienic practice was more effective at lowering PbB than reducing ambient lead level. Good hygienic practice may be the preferential way to reduce lead exposure in current conditions. Conclusion: Education of correct work practice may be more important than engineering control in the developing countries to lower blood lead levels in lead battery factories. Received: 28 May 1996/Accepted: 30 August 1996  相似文献   
34.
The hereditary characteristics of enzyme deficiency and dermatoglyphics in congenital color blindness (CCB) were studied. We propose that there is a linkage between the two loci on the X-chromosome determining CCB and glucose-6-phosphate dehydrogenase (G6PD), based on our study of a high incidence of G6PD deficiency in 156 male cases with CCB. The CCB gene is closely linked with that of G6PD deficiency from our pedigree investigations. The rise in the frequency of eight or more whorls, the low value of atd angle and the presenting rate of real palmar patterns of the thenar, hypothenar and I, areas presented the hereditary traits of congenital color blindness.  相似文献   
35.
The visual pursuit test is a method that collects and analyzes the characteristics of pursuit eye movements and examines the function of the eye movement system. This paper analyzes the model parameters of the smooth pursuit eye movement system in order to explore a method for improving the analysis. The input-output relationship of the smooth pursuit system can be expressed by a quasilinear model. We compute the model parameters (gain, phase, spectral purity, cross covariance) by digital signal processing. Eye movement is recorded by electrooculogram. Both eyes are tested individually. The visual target moves at frequencies of 0.2, 0.4, 0.8, 1.2, and 1.6 Hz. Ranges are gain, 1.01 to 0.70; phase, -0.1 ° to -66 °; spectral purity, 0.97 to 0.70; and cross covariance, 0.99 to 0.26. We tested 40 normal subjects as well as patients with ataxia (8), vertigo (18), and ophthalmoplegia (9). The oculomotor system of normal subjects functions as a linear system in the performance of this test at 0.2 to 0.8 Hz. The spectral purity dropped to about 0.70 at 1.6 Hz. The variability of all measures increases greatly at 1.6 Hz, which indicates that this target motion exceeds the tracking ability of many normal subjects and that the oculomotor system of normal subjects functions as a nonlinear system in this condition. Statistical tests show no significant differences between sex, age, and the two eyes. The model parameters tentatively proved effective in clinical application.  相似文献   
36.
本文在分析黑龙江省妇幼保健机构设置现状的基础上,论述了在社会主义市场经济新形势下,妇幼保健机构发展的指导思想、模式与对策。  相似文献   
37.
T Wu 《中华医学杂志》1990,70(2):72-6, 6
At extreme altitude of 5,620 m, cardiac function was examined with electrical impedance at rest and during exercise. Mountaineers as subjects of experiment were divided into two groups: 15 subjects were Tibetan natives, and 10 subjects were Han visitors of expedition (both were young healthy males). The results showed that no significant difference was seen between the two groups in cardiac pump function at rest. In the Han visitors during exercise, HR increase was restricted, SV and CO were decreased, and PEP/LVET ratio was increased. In the Tibetan natives, HR increased gradually with increased work load, SV tended to be stable CO increased significantly under higher work load, and PEP/LVET ratio decreased gradually. These results suggest that the Tibetan natives were adapted to hypoxic environment much better than the immigrants because their cardiac reserve capacity and maximal oxygen uptake were better than the immigrants at extreme altitude.  相似文献   
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目的:利用单光子发射计算机断层摄影(SPECT)半定量分析有效控制与控制不良的MRI阴性的全面性强直阵挛发作癫(GTCS)病人的局部脑血流差异,探讨脑血流灌注与其预后的关系.材料和方法:对29例有效控制的和12例控制不佳的MRI阴性的GTCS病人进行发作间期99mTc-ECD-SPECT脑血灌流显像,10例年龄匹配的健康人作对照,用感兴趣区(ROI)的不对称指数(%AI)进行半定量分析.将SPECT分析结果与病人的临床表现与EEG相比较.结果:①控制不佳组与有效控制组在丘脑和基底节区的%AI存在显著性差异(P<0.05);②控制不佳组SPECT脑显像的异常率(83.3%,10/12)明显高于有效控制组的异常率(17.2%,5/29),两组具有显著性差异(P<0.01);而两组病人的EEG异常率分别为58.3%、44.8%(7/12、13/29),无显著性差异(P>0.05).结论:控制不佳的MRI阴性的GTCS病人往往存在发作间期的低血流灌注脑区,提示癫的难治性;而控制良好的病人多无明显异常发现,可能预后较好.  相似文献   
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