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Joel Haycock 《Death Studies》1991,15(5):417-433
Suicide in jails is a growing public health problem. It is growing because the suicide rate among young men has increased sharply in the last 20 years and because the recent historic increases in the U.S. rate of jail incarceration have put more and more men, young and old, behind bars. This article reviews the empirical studies resulting from the new attention given jail-suicide research and prevention in the last decade. The author argues that the findings of this literature need to be treated with great caution. The second part of the article considers explanations of the greater risks for completed suicides in jail. The causes for the high rate of jail suicide must lie in the types of people who find themselves in jail (“importation” explanations) or in what jails are like (“deprivation” explanations). A large number of the risk factors for completed and attempted suicide in the general population are overrepresented among jail populations, and the article reviews some of these risk factors. Although this importation case has merit, it is only a partial explanation for the high rate of jail suicide. In contradiction to the assumptions of stricter importation theorists, newer, non-suicide-related research on jail populations has strongly indicated that some part of the elevated rates of inmate distress may be attributed to the effects of exposure to jail environments. The author concludes that new studies notwithstanding, the empirical research base on jail suicide remains very limited. Several avenues for new investigations are suggested. 相似文献
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Short-Ti inversion-recovery pulse sequence: analysis and initial experience in cancer imaging 总被引:2,自引:0,他引:2
Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy. 相似文献
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Sixteen cases of histopathologically proved solitary rectal ulcer syndrome were encountered. Fifteen patients underwent barium enema study; in nine cases the findings--including rectal stricture, granularity of the mucosa, and thickened rectal folds-were nonspecific. In six cases the study was normal. All patients had a long history of defecation disorders, and defecography was performed in all. In seven cases, intussusception of the rectal wall was seen; in another case the intussusception was accompanied by a rectocele. One case showed rectal prolapse. In four cases, failed relaxation of the puborectalis occurred and prevented the passage of the bolus; in another case there was abnormal perineal descent. In two patients studies were normal. In patients with defecation disorders, the possibility of this syndrome should be considered. Defecography is the method of choice for establishing the diagnosis. 相似文献
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