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Stimulation of net secretion by deoxycholic acid (DCA) in the colon and by cholera enterotoxin (CE) in the jejunum is mediated by cAMP. Propranolol (Pr) inhibits adenylate cyclase (AC) activity and net secretion induced by bile acid in the colon. The aim of this study was to assess the organ specificity of DCA and CE as well as the selectivity of Pr inhibition. Three colonic and three jejunal loops were prepared in each of 8 rabbits treated intravenously with Pr, 4 mg per kg, 1/2 hr before loop construction and in each of 10 untreated control rabbits. One milliliter of DCA, 6 mM, CE, 10 mug per ml, or heat-inactivated CE or 0.9% NaCl, as basal controls were injected in random order into each of the loops. The volume of luminal fluid and mucosal AC were measured in each intestinal loop 5 hr later. DCA in the colon stimulated AC 2-fold (P less than 0.01) and luminal fluid 15-fold (P less than 0.01). CE in the jejunum stimulated AC 2.3-fold (P less than 0.01) and luminal fluid 9-fold (P less that 0.01). No significant effects on volume or AC occurred in response to CE in the colon or to DCA in the jejunum. Pr pretreatment completely prevented the stimulation of AC and luminal fluid by DCA in the colon but did not affect the action of CE in the jejunum of the same animals. Thus, DCA and CE are organ-specific stimulants of cAMP systems, and Pr is a selective inhibitor of certain inducers of cAMP and net secretion.  相似文献   
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Treatment-induced cortical reorganization after stroke in humans   总被引:68,自引:0,他引:68  
BACKGROUND AND PURPOSE: Injury-induced cortical reorganization is a widely recognized phenomenon. In contrast, there is almost no information on treatment-induced plastic changes in the human brain. The aim of the present study was to evaluate reorganization in the motor cortex of stroke patients that was induced with an efficacious rehabilitation treatment. METHODS: We used focal transcranial magnetic stimulation to map the cortical motor output area of a hand muscle on both sides in 13 stroke patients in the chronic stage of their illness before and after a 12-day-period of constraint-induced movement therapy. RESULTS: Before treatment, the cortical representation area of the affected hand muscle was significantly smaller than the contralateral side. After treatment, the muscle output area size in the affected hemisphere was significantly enlarged, corresponding to a greatly improved motor performance of the paretic limb. Shifts of the center of the output map in the affected hemisphere suggested the recruitment of adjacent brain areas. In follow-up examinations up to 6 months after treatment, motor performance remained at a high level, whereas the cortical area sizes in the 2 hemispheres became almost identical, representing a return of the balance of excitability between the 2 hemispheres toward a normal condition. CONCLUSIONS: This is the first demonstration in humans of a long-term alteration in brain function associated with a therapy-induced improvement in the rehabilitation of movement after neurological injury.  相似文献   
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OBJECTIVE: To assess psychotropic drug utilization in the general population of six European countries, and the pattern of use in individuals with different DSM-IV diagnoses of 12-month mental disorders. METHOD: Data were derived from the European Study of the Epidemiology of Mental Disorders (ESEMeD/MHEDEA 2000), a cross-sectional psychiatric epidemiological study in a representative sample of 21 425 adults aged 18 or older from six European countries (e.g. Belgium, France, Germany, Italy, the Netherlands and Spain). Individuals were asked about any psychotropic drug use in the past 12 months, even if they used the drug(s) just once. A colour booklet containing high-quality pictures of psychotropic drugs commonly used to treat mental disorders was provided to help respondents recall drug use. RESULTS: Psychotropic drug utilization is generally low in individuals with any 12-month mental disorder (32.6%). The extent of psychotropic drug utilization varied according to the specific DSM-IV diagnosis. Among individuals with a 12-month diagnosis of pure major depression, only 21.2% had received any antidepressants within the same period; the exclusive use of antidepressants was even lower (4.6%), while more individuals took only anxiolytics (18.4%). CONCLUSION: These data question the appropriateness of current pharmacological treatments, particularly for major depression, in which under-treatment is coupled with the high use of non-specific medications, such as anxiolytics.  相似文献   
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Abstract

Comprehension of typewritten informed consent information was evaluated for young-old (60–69 years) through old-old (80–89 years) volunteers as a function of years of education (< 12, 12, and > 12), readability of information (low [college level] vs high [7th grade]), and typeface used in the preparation of the materials (Prestige Elite 72, Letter Gothic, and Orator). All volunteers (N = 235) read a typewritten information sheet and retained it for review while answering eight multiple choice questions. Immediate feedback was provided, and a second test was administered if any answers were incorrect. The findings indicated that comprehension varied directly with education and inversely with age. Typeface and age interacted due to age-related differences with the two smaller (Prestige Elite and Letter Gothic), but not with the largest of the typefaces (Orator). These findings suggest that the observed age-related differences may have been due to visual and not cognitive deficits. Readability did not affect performance either by itself or in combination with any other variable.  相似文献   
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