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Evaluation of an on-line patient exposure meter in neuroradiology   总被引:1,自引:0,他引:1  
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Thirteen morbidly obese individuals were studied prospectively for 1 year after vertical banded gastroplasty (VBG) to determine the relationships between energy balance equation parameters and excess weight loss. The measured energy expenditure (MEE), as determined by indirect calorimetry, was not correlated with weight loss. However, when this parameter was expressed as a ratio to the predicted energy expenditure (PEE), the ratio was significantly correlated with the postoperative excess weight loss at 2, 6, and 12 months. The mean daily energy intake after the VBG was 2715 +/- 865 kJ. The postoperative energy intake was not correlated with the excess weight loss. Diet-induced thermogenesis was studied in eight patients. The mean diet-induced thermogenesis was 10.31% +/- 13.92%. The diet-induced thermogenesis was not correlated with the postoperative excess weight loss. The preliminary findings of this trial suggest that the MEE/PEE ratio is useful in predicting excess weight loss after VBG.  相似文献   
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人体液中喷布洛尔及其代谢物的GC/MS分析   总被引:1,自引:0,他引:1  
用气相色谱一质谱联用(GC-MSD)系统分析方法检出了人尿中喷布洛尔的6个羟化代谢物,用Scp-Pak柱提取的方法检出了人血浆中的原型药物。并从分子结构上对此药物的代谢途径进行了研究。尿中提取和血中提取的回收率分别为90.83.%和85.88%,Gc-MSD的检测限为5pg。本方法适用于运动员兴奋剂的系统检查。  相似文献   
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Twenty-four nonsmoking male volunteers took 50 mg atenolol or 10 mg betaxolol orally once a day for 9 days in a two-period, four-sequence, randomized, crossover study. Plasma concentrations reached steady state after day 5. Percent fluctuation in plasma concentration defined as (Cmax-Cmin)/Cavg (% fluctuation 1) was 97% on day 9 for betaxolol and 343% for atenolol; thus atenolol fluctuation was more than threefold that of betaxolol. A 10-fold difference in plasma level fluctuation was observed when fluctuation was defined as (Cmax-Cmin)/Cmin (% fluctuation 2). The intersubject variances for % fluctuation 1 and % fluctuation 2 were 4.1 and 85.5 times greater for atenolol than for betaxolol; these differences were marginally statistically significant for % fluctuation 1 and significant for % fluctuation 2. The intrasubject variabilities for area under the curve and plasma level fluctuations were statistically greater for atenolol than for betaxolol. Atenolol intrasubject variances were 25 and 271 times greater than for betaxolol for % fluctuation 1 and % fluctuation 2, respectively. Thus, betaxolol exhibited less fluctuation in plasma levels with substantially less intersubject and intrasubject variability. These factors would be expected to provide a more consistent therapeutic response and more dependable dosage adjustment.  相似文献   
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Trauma und Berufskrankheit - Die deutschen Durchgangsärzte arbeiten mit einer sowohl medizinisch als auch finanziell seit langem überholten Gebührenordnung. Im vorliegenden Vortrag...  相似文献   
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According to Beck's original theory, depressives make unwarranted negatively biased personal inferences. Specifically, Beck suggested that depressives ignore current positive situational information and are unduly influenced by current negative situational information in making inferences. To test Beck's theory, we used Kelley's normative model of causal inference to examine the utilization of causally relevant situational information by dysphoric, nondepressed, and very nondepressed subjects in making causal attributions for personal success and failure. We used Stevens and Jones' classic method from social psychology and embedded the relevant causal information in the natural flow of events. Results showed that dysphoric, nondepressed, and very nondepressed subjects did, to an equal degree, use such information to make causal attributions. Although dysphoric and both groups of nondepressed subjects used current situational information consistently with Kelley's model, clear-cut baseline differences in the content of their causal attributions existed. Thus, the results supported the reformulations of Beck's theory that emphasize content, rather than process, differences between depressive and nondepressive cognition for dysphoria.Preparation of this article was supported by a Vilas Award, a University of Wisconsin Graduate School Grant, a Romnes Fellowship, a Biomedical Grant, and NIMH Grant R01MH43866 to Lyn Y. Abramson.  相似文献   
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X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG repeat expansion in the first exon of the androgen receptor (AR) gene. Disease-associated alleles (37-66 CAGs) change in length when transmitted from parents to offspring, with a significantly greater tendency to shift size when inherited paternally. As transgenic mice carrying human AR cDNAs with 45 and 66 CAG repeats do not display repeat instability, we attempted to model trinucleotide repeat instability by generating transgenic mice with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions in their genomic context. Studies of independent lines of AR YAC transgenic mice with CAG 45 alleles reveal intergenerational instability at an overall rate of approximately 10%. We also find that the 45 CAG repeat tracts are significantly more unstable with maternal transmission and as the transmitting mother ages. Of all the CAG/CTG repeat transgenic mice produced to date the AR YAC CAG 45 mice are unstable with the smallest trinucleotide repeat mutations, suggesting that the length threshold for repeat instability in the mouse may be lowered by including the appropriate flanking human DNA sequences. By sequence-tagged site content analysis and long range mapping we determined that one unstable transgenic line has integrated an approximately 70 kb segment of the AR locus due to fragmentation of the AR YAC. Identification of the cis - acting elements that permit CAG tract instability and the trans -acting factors that modulate repeat instability in the AR YAC CAG 45 mice may provide insights into the molecular basis of trinucleotide repeat instability in humans.   相似文献   
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