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931.
Substance abuse testing and treatment programs for adolescents using drugs are receiving increased attention on high school campuses. Many policymakers question drug testing and the treatment models for adolescent substance abusers. This paper explores the impact of drug testing. Treatment models and approaches for substance abuse are presented. It is recommended that treatment counselors explore drug testing in relationship to treatment models for substance use. We advise counselors to consider comprehensive programs for adolescents based on their belief systems and values assigned to moral, medical and social models of treatment.  相似文献   
932.
There is growing evidence that a spectrum of chondrodysplasias are caused by mutations in the gene coding for type II collagen. The basic molecular defect in diastrophic dysplasia has not been defined, but it appears not to be in collagen type II. Cartilage contains other tissue-specific collagens, types IX, X, and XI, but no mutations have yet been found in their genes in clinical disease. Type IX collagen is hypothesized to play a role in the regulation of type II collagen fibril organization and structure in cartilage extracellular matrix. In this study, we have examined iliac crest growth cartilage from a patient with diastrophic dysplasia. Although collagen fibrils were markedly increased in diameter on transmission electron microscopy, type II collagen appeared to be normal biochemically. Type XI collagen was also normal. However, type IX collagen appeared abnormal on sodium dodecyl sulfate polyacrylamide gel electrophoresis with a pronounced excess of the COL1 domain of the molecule in pepsin extracts. The findings point to an abnormality in structure or metabolism of type IX collagen in diastrophic dysplasia. © 1994 Wiley-Liss, Inc.  相似文献   
933.
Essential fructosuria is one of the oldest known inborn errorsof metabolism. It is a benign condition which is believed toresult from deficiency of hepatic fructokinase (ketohexokinase,KHK, E.C.2.7.1.3). This enzyme catalyses the first step of metabolismof dietary fructose, conversion of fructose to fructose-1-phosphate.Despite the early recognition of this disorder, the primarystructure of human KHK and the molecular basis of essentialfructosuria have not been previously defined. In this report,the isolation and sequencing of full-length cDNA clones encodinghuman ketohexokinase are described. Alternative mRNA speciesand alternative KHK isozymes are produced by alternative polyadenylationand splicing of the KHK gene. The KHK proteins show a high levelof sequence conservation relative to rat KHK. Direct evidencethat mutation of the KHK structural gene is the cause of essentialfructosuria was also obtained. In a well-characterized family,in which three of eight siblings have fructosurla, all affectedindividuals are compound heterozygotes for two mutations Gly40Argand Ala43Thr. Both mutations result from G  相似文献   
934.
Eighteen patients with chronic constipation were diagnosed as having paradoxical puborectalis contraction (PPC) as the cause for their constipation. The diagnosis of PPC was made after office evaluation, colonic transit study, manometry, cinedefecography, and electromyography (EMG). These 18 patients had a mean duration of symptoms of 26.9 years; none of these patients had unassisted bowel movements. Fourteen patients had a mean of 4.6 laxative-induced bowel evacuations per week, and 11 patients had a mean of 4.4 enema-induced bowel evacuations per week. Patients underwent a mean of 8.9 one-hour EMG-based biofeedback sessions. At a mean follow-up of 9.1 (range, 0.5–12) months, these 18 patients had a mean of 7.3 unassisted bowel actions per week ( P <0.0001). In addition, persistent laxative use was reported by only two patients, and, in both cases, this was once a week or less ( P <0.001). Similarly, enema use was reported by only three patients, one once weekly and the other two thrice weekly ( P <0.002). No biofeedback-related complications were identified. EMG-based biofeedback is a valuable technique associated with an 89 percent success rate in the treatment of PPC.Read at the meeting of The American Society of Colon and Rectal Surgeons, Boston, Massachusetts, May 12 to 17, 1991.  相似文献   
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938.
Three hypotheses for cognitive deficits among psychopaths were tested: executive dysfunction, left hemisphere activation, and an interaction between the two. Twenty-one psychopathic and 23 nonpsychopathic criminal offenders identified with the Hare Psychopathy Checklist-Revised participated in verbal and visual-spatial tasks during which the level of executive processing demands was manipulated. Consistent with prior research, psychopathic offenders made more errors than controls, but only during the verbal task and only on trials with high executive demand. Within those trials, most errors occurred when set-maintenance demands were the highest. No response latency differences between groups were found.  相似文献   
939.
940.
Gastric mucormycosis involvement is a rare condition that usually occurs in inmunocompromised patients and frequently has a fatal outcome. We report the case of a 73‐year‐old woman admitted to the intensive care unit with severe bleeding after an acute pulmonary disease. Upper endoscopy disclosed wide and deep necrotic ulcers in the body and fundus of the stomach and greenish exudates with the antrum and the duodenum undamaged. Autopsy revealed an invasive mucormycosis and a severe atheromatosis. Several predisposing factors for mucormycosis infection have been reported until now. We postulate that ischemic gastritis could be a predisposing factor for colonization of zygomycete.  相似文献   
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