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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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BACKGROUND: Computer-assisted image analysis has been proposed for human hair growth studies. METHODS: The performances of Trichoscan, a commercially available automated system combining epiluminiscence microscopy with digital image analysis, developed for office-based hair growth measurements, have been evaluated comparatively on the same skin sites using standardized photographic equipment and calibrated processing for contrast-enhanced phototrichogram (CE-PTG) analysis. This reference method has been validated with scalp biopsies and histological examination of serial sectioning. RESULTS: Besides edge effects, hair fibres escaped the Trichoscan analysis for various reasons including, but not limited to, thickness, pigmentation, closeness and crossing. CONCLUSION: Most of these problems have been identified in the late 1980s and remain largely unsolved by the processing software that was evaluated in 2004. Therefore claims promoting the Trichoscan method for accurate hair measurements in clinical trials on scalp and body hair are not supported by the present investigation. The speed at which the analysis is performed is outweighed by the errors in signal detection. Therefore we suggest that improvements must be clearly documented before Trichoscan is established for quantified diagnostic purposes and detailed hair cycle monitoring during hair trials.  相似文献   
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双波长紫外分光光度法测定贝母中腺苷和胸苷的含量   总被引:4,自引:0,他引:4  
将4种贝母的甲醇提取物经薄层色谱法粗分离后,直接用双波长紫外分光光度法测定其含量。结果表明,该方法线性关系好,腺苷和胸苷标准曲线的相关系数均为0.9999,同时也发现平贝、炉贝和伊贝中腺苷都占核苷总量60%以上,而浙贝中仅占约40%,提示贝母生药的抗凝血活性可能与贝母中核苷类化合物的种类和含量的差别有关。  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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