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The indirect hemagglutination test was used to study antibody titers to Entamoeba histolytica in different Malaysian populations. Eighty-seven percent of Orang Asli (western Malaysian aborigines) adults and 79% of Orang Asli children with acute amebic dysentery were seropositive. However, significantly fewer children (39%) with amebic dysentery had high titer responses (titer greater than or equal to 1:1,280) than did adults with amebic dysentery (76%). No correlation between proctoscopic severity and amebic titer was found. Forty-four percent of asymptomatic family members were seroresponders. Satak, an Orang Asli village located near towns, had significantly more seroresponders (32%) than did the isolated, deep jungle village, Belatim (4%).  相似文献   
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In 5 patients with pharmacologically intractable epilepsy, biopsy of the cerebellar cortex at the time of surface electrode implantation for therapeutic stimulation demonstrated marked degeneration of the Purkinje cell layer in every case. Two of the patients had never experienced a generalized convulsion. Comparison of these biopsy findings with the autopsy findings in two other groups of patients with a seizure disorder of different duration and severity and with the findings in other reported series suggests that permanent neuronal damage in epilepsy is related to the cumulative effects of the frequency and chronicity of the disorder. The pathogenesis remains unclear. The histopathological changes are identical to those seen in generalized cerebral hypoxia, but the observations in our series support the view that in epilepsy the pathogenesis may not be hypoxic.  相似文献   
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A cancer DNA phenotype, identical to the DNA structure of tumors, has been identified in the prostate glands of certain healthy men over 55 years of age. We now show that the same DNA signature exists in normal tissues adjacent to tumors. This finding implies that the phenotype is maintained in normal prostate cells from its inception through tumor development. The presence of the phenotype in tumors, adjacent normal cells, and in the normal prostate cells of certain older men suggests that it is a potentially critical factor in tumor development and may serve as an early biomarker for cancer risk assessment. Intervention to inhibit the development of the phenotype in healthy men, or to eliminate it once formed, may suppress or even prevent tumor formation.  相似文献   
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PURPOSE: To determine the prevalence of epilepsy and the role of neurocysticercosis in the occurrence of epilepsy in Atahualpa. METHODS: We used a door-to-door survey to detect subjects with epileptic seizures, to collect a blood sample for determination of anticysticercal antibodies, and to evaluate social characteristics of the population, including household pig ownership. Neurologists examined suspected cases and a sample of negative individuals. Then patients with epilepsy, as well as age- and sex-matched controls, underwent a head computed tomography (CT) and a scalp EEG. RESULTS: The questionnaire was answered by 2,415 of 2,548 residents of Atahualpa, and cysticercosis serology was performed in 1,687 consenting individuals. Cysticercosis seroprevalence was 145 (8.6%) per 1,686). Neurologic examination confirmed 24 patients with epilepsy (crude prevalence, 9.9 per 1,000 population, and 10.8 per 1,000 when adjusted to the United States population). After adjustment by age, sex, and pig raising, positive serology was strongly associated with epilepsy (odds ratio (OR), 4.16; 95% confidence interval (CI), 1.6-11.2). CT findings compatible with neurocysticercosis were found in five patients with epilepsy and also were more frequent than in controls, although this did not reach statistical significance (five of 19 vs. one of 19; p = 0.125, McNemar's test). Besides these five cases, three other patients with epilepsy had positive serology (one with a normal CT and two who did not have a CT). CONCLUSIONS: Neurocysticercosis is associated with one-third of cases of epilepsy in Atahualpa and may be a major contributory factor for the excess fraction of epilepsy seen in this population.  相似文献   
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