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Almost all investigations of first-episode schizophrenia uncover more male than female subjects. Two possible explanations for this observation are (1) first-episode investigations suffer more or less consistent methodologic biases or (2) the incidence of schizophrenia is higher in men than in women. Data from the markers and predictors of schizophrenia (MAP) project, a community-based first-episode study, permitted an investigation of the two alternatives. The results suggest that neither recruitment nor diagnostic vagaries explain the excess of males. Instead, the MAP results, consistent with other recent investigations, suggest that the incidence of schizophrenia is lower in women than in men. The findings are consistent with the literature on gender differences in schizophrenia, which indicates that schizophrenia in women is a less severe disorder than in men. The report includes recommendations for future first-episode investigations to ensure adequate representation of women. 相似文献
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Low-artifact intravascular devices: MR imaging evaluation 总被引:2,自引:0,他引:2
Teitelbaum GP; Ortega HV; Vinitski S; Stern H; Tsuruda JS; Mitchell DG; Rifkin MD; Bradley WG Jr 《Radiology》1988,168(3):713-719
Flow-phantom magnetic resonance (MR) imaging, with use of both spin-echo (SE) and gradient-echo (GRE) techniques at 1.5 T, was performed on the percutaneous Greenfield (beta-III titanium alloy [TMA wire]), Amplatz (MP32-N alloy), and Simon nitinol filters and TMA wire facsimiles of the bird's nest, Gunther, new retrievable, and Amplatz vena caval filters. SE imaging allowed detection of thrombi as small as 5 X 5 mm trapped within the percutaneous Greenfield, Simon nitinol, and TMA-wire facsimile filters; with the MP32-N Amplatz filter, a larger volume of thrombus (10 X 20-mm clots) was necessary for clot detection. GRE imaging allowed detection of intraluminal tilting of the percutaneous Greenfield and facsimile Amplatz (TMA-wire) filters. GRE imaging was useful for demonstrating postfilter turbulence due to clots, which was greatest for the Amplatz filter. Imaging of facsimile vascular devices made of tantalum or TMA wire did not cause the severe "black-hole" MR artifacts typical of the stainless-steel devices. SE and GRE imaging were very useful for determining caval patency in two patients with previously placed Mobin-Uddin filters. Noninvasive MR evaluation of blood vessels in the presence of a variety of low-artifact intravascular devices appears feasible. 相似文献
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To determine the usefulness of including a duration criterion in the definition of "negative" symptoms, the prognostic significance of a longitudinally obtained measure of negative symptoms was compared with a cross-sectionally obtained measure. As predicted, the presence of negative symptoms based on longitudinal observation was associated with most aspects of 18-month course in a group of "first-episode" schizophrenic individuals, whereas cross-sectional levels of negative symptoms were not. The findings suggest that negative symptoms, when operationalized as a trait-like phenomenon, help to portend a poor course of illness. 相似文献
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Variability of skin temperature in the waking monkey 总被引:3,自引:0,他引:3
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Rao VM; Dalinka MK; Mitchell DG; Spritzer CE; Kaplan F; August CS; Axel L; Kressel HY 《Radiology》1986,161(1):217-220
Four patients with proved osteopetrosis (three with the infantile malignant form and one with the benign form) were examined with magnetic resonance imaging at 1.5 T. All patients were studied in the coronal and sagittal planes using both short and long repetition time/echo time sequences. The infantile malignant form was characterized by a complete lack of signal from the marrow alternating with a signal intensity equivalent to that of the intervertebral disks, resulting in a "stepladder" appearance. In the benign form or after successful marrow transplantation in the infantile malignant form, intermediate or high signal intensity in the vertebrae was noted, suggesting the presence of some marrow elements. 相似文献