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The finding of clinical and laboratory differences between schizophrenic patients with large and small cerebral ventricles has led to the widespread assumption that large ventricles are a marker that characterizes a subgroup of patients with schizophrenia. We reviewed all published English language ventricle-to-brain ratio (VBR) studies in which individual data points were available (schizophrenics: n = 691, medical controls; n = 205, normal volunteers: n = 160). Using a univariate normal mixture model to examine the distribution of ventricular size in each group, we found no evidence of a mixture of Gaussian distributions (i.e., "bimodality") within any of the three groups. The same analysis was then performed on the combined sample of schizophrenic patients and normal and medical controls, respectively. In each case the improvement in fit of a mixture of normal distributions compared to a single component normal distribution was significant. The data do not support the notion that ventricular enlargement is a discontinuous marker of a subtype of schizophrenia.  相似文献   
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We performed a community-wide study in metropolitan Baltimore to examine the prognostic role of length of time between hospital admission and ventricular fibrillation or cardiac arrest (VFib/CA) complicating acute myocardial infarction (MI). Risk of developing VFib/CA was particularly marked in the first few hours after admission to the hospital. We compared 128 patients experiencing VFib/CA within 48 hours of admission and 80 patients developing these complications after more than 48 hours. Patients with "early" VFib/CA exhibited a lower in-hospital case-fatality rate than those with "late" VBib/CA (67% versus 88%; p less than .01). Likewise, of patients discharged alive from the hospital and followed for as long as six years a greater proportion of the 38 with histories of "early" VFib/CA survived than of the 11 who had experienced "late" VFib/CA during hospital admission (.05 less than p less than .10). These results suggest that whereas "early" VFib/CA may reflect transitory myocardial electrical instability, "late" VFib/CA may indicate chronic instability and thus imply a poor prognosis.  相似文献   
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An incubation system containing rat jejunoileum was used to determine whether analogues of cyanocabalamin (CNCbl) inhibited the in vitro absorption of CNCbl. The naturally occurring analogues "pseudo B12," "factor A," and the nonnaturally occurring analogue desdemethyl B12, were produced by guided biosynthesis with Propionibacterium arabinosum. Factor B was produced by acid cleavage of cyanocabalamin. Inhibition of Co57-CNBbl uptake was demonstrated for cold CNCbl and for desdemethyl B12, although statistical significance was achieved only for cold CNCbl at 40X and 100X the molar quantity of the radiolabeled CNCbl. However, a trend towards progressive inhibition of specific CNCbl binding was shown as increasing concentrations of CNCbl or desdemethyl B12 were used. No inhibition of specific CNCbl binding could be demonstrated for any of the naturally occurring cobamides tested.  相似文献   
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An employee incentive program in this HMO not only improved the quality of services offered and maintained them at a more cost-efficient level, but also benefitted employees through added income.  相似文献   
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Hypertension may result from chronic lead exposure. Lead poisoning arising from "moonshine whiskey" drinking has been associated with a rise in plasma renin activity. In the present study, plasma renin concentration following intravenous administration of frusemide was measured in eleven subjects with moderate or severe lead poisoning of industrial origin. The results were compared with those obtained for seven normal, control subjects. There was no significant difference in response obtained in the two groups. Industrial lead poisoning does not appear to affect renin release. The combined insult of lead and alcohol may explain the findings in the previous study.  相似文献   
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An existential perspective on human suffering suggests that the psychoanalytic view of the unconscious poses a difficult dilemma in regard to self-examination: On the one hand, not to pursue introspection may leave one as a person driven by untoward instinctual urges; on the other hand, to vigorously self-reflect, may result in inexorable despair in regard to the limitations and finitude of mortal existence. The author contends that the reason for the dilemma is rooted in Western psychology--a perspective that regards the human being as an encapsulated consciousness, set separately and competitively apart from other objects in the cosmos. This orientation is shown to pose difficulties in treating madness and despair. By the use of clinical material, the author shows how Martin Buber's notion of authentic dialogue can be useful in efforts to bridge the separation between the sufferer and the healer.  相似文献   
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