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1.
Cognitive Therapy and Research - Despite interest in psychological inflexibility as a marker of suicide risk, no measure of psychological inflexibility specific to SI exists. The present study...  相似文献   
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A chemically defined medium for the culture of mature oligodendrocytes   总被引:3,自引:0,他引:3  
A new chemically defined medium consisting of equal parts of Dulbecco modified Eagle's and Ham's F-12 media supplemented with insulin, sodium selenite, putrescine, and D+ galactose, which allows the long-term survival of mature oligodendrocyte pure cultures, is described. Immunohistochemical staining has shown that over 90% of the cells become positive for myelin proteins shortly following subculture. Contaminating astrocytes (2%) do not survive in this medium. Biochemical data have indicated that these purified oligodendrocytes express 2'3'-cyclic nucleotide 3'-phosphohydrolase and UDP-galactose ceramide galactosyltransferase activities. Electron microscopical examination revealed that the oligodendrocytes were mostly of medium-dark type and appeared to be identical to cells cultured in serum-containing medium. The ability to maintain pure oligodendrocyte cultures in such a defined medium will allow investigations concerning exogenous and endogenous factors involved in oligodendrocyte metabolism.  相似文献   
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Vitamin D-independent expression of chick brain calbindin-D28K.   总被引:1,自引:0,他引:1  
A combination of calbindin-D28K-specific cDNA probes and polyclonal antisera were used to investigate expression of the calbindin-D28K in the vitamin D-deficient avian brain in vivo in response to pharmacological doses of the vitamin D3 metabolite, 1,25-dihydroxyvitamin D3 (1,25(OH)2D3). Serum calcium levels were stimulated (2-fold) and intestinal calbindin-D28K expression (between 10- and 30-fold) by 1,25(OH)2D3 (6.5 nmol/animal) after 12 h. In marked contrast, steady-state whole brain levels of calbindin-D28K as judged by enzyme-linked immunoassay (ELISA) remained constant. Northern gel analysis revealed that three species of calbindin-D28K mRNA (2.0, 2.6 and 3.1 kb) were present a priori in the vitamin D-deficient chick brain and that administration of pharmacological doses (6.5 nmol/animal) of 1,25(OH)2D3 failed to influence their relative abundance. Separate but parallel dot blot hybridization analyses also confirmed that brain calbindin-D28K-mRNA levels were not influenced by 1,25(OH)2D3. These experiments demonstrate at the molecular level that, in contrast to the intestine, the gene encoding calbindin-D28K in the brain is regulated by mechanism(s) or factors which are independent of vitamin D status.  相似文献   
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Anorectal function in the solitary rectal ulcer syndrome   总被引:8,自引:6,他引:2  
The anorectal function of nine patients with solitary rectal ulcer syndrome (SRUS) (5 F: 4 M, median age, 27 (range, 19–41 years) and nine control subjects (5 F: 4 M, median age, 47 (35–66)P<0.01) has been investigated by a new technique that radiologically visualizes the anorectum during voiding of a semisolid contrast medium, while simultaneously measuring intrarectal pressure and anal sphincter EMG activity. A degree of rectal prolapse was demonstrated in eight of the SRUS patients; six of these lesions were clinically occult. Abnormal failure of the anal sphincter to relax on voiding was present in seven of the SRUS patients. These abnormalities resulted in the SRUS patients requiring a greater increase in intrarectal pressure (median, 100 cm water) to void than the control subjects (median, 65 cm water,P<0.01). This combination of high intrarectal pressure and rectal prolapse during straining seems to be the cause of SRUS This work was supported by a grant from the Medical Research Council.  相似文献   
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1. Twenty-two patients hospitalized for treatment of depression were treated under conditions simulating those of home treatment. 2. Full doses of nortriptyline, from 100 to 150 mg/day, were started after baseline observations were made. 3. Two patients were dropped from the study, one for orthostatic hypotension, one for an aberrant response to nortriptyline. Two additional patients developed orthostasis which was easily managed. Otherwise no unusual side effects were noted. 4. After six days of treatment, 9 of 20 patients showed significant improvement with an overall reduction in scores on the Hamilton Depression Scale of 49% for the entire group. 5. Using the weight-adjusted dosage schedule, 18 of the 21 patients attained plasma concentrations of nortriptyline within the presumed therapeutic range; however, no clear relationship could be established between plasma concentrations and clinical response. 6. With proper selection of patients, it should be possible to treat at home some patients who currently are considered to require hospitalization.  相似文献   
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