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E Boehm V Veksler P Mateo C Lenoble B Wieringa R Ventura-Clapier 《Canadian Metallurgical Quarterly》1998,30(5):901-912
The importance of mitochondrial creatine kinase (mi-CK) in oxidative muscle was tested by studying the functional properties of in situ mitochondria in saponin-skinned muscle fibres from sarcomeric mi-CK-deficient (mutant) mice. Biochemical analyses showed that the lack of mi-CK in mutant muscle was associated with a decrease in specific activity of MM-CK in mutant ventricle, and increase in mutant soleus (oxidative) muscle. Lactate dehydrogenase activity and isoenzyme analysis showed an increased glycolytic metabolism in mutant soleus. No change was observed in ventricular muscle. In control animals, the apparent K(m) of mitochondrial respiration for ADP in ventricle and soleus (232 +/- 36 and 381 +/- 63 microM, respectively) was significantly reduced in the presence of creatine (52 +/- 8 and 45 +/- 12 microM, respectively). There was no change in the K(m) in oxidative fibres from mutant mice (258 +/- 27 and 399 +/- 66 microM, respectively) compared with control, though surprisingly, it was also significantly decreased in the presence of creatine (144 +/- 8 and 150 +/- 27 microM, respectively) despite the absence of mi-CK. It is proposed that in mutant (and perhaps normal) oxidative tissue, cytosolic MM-CK can relocate to the outer mitochondrial membrane, where it is coupled to oxidative phosphorylation by close proximity to porin, and the adenine nucleotide translocase. Such an effect can preserve the functioning of the CK shuttle and the energetic properties of mi-CK deficient tissue. 相似文献
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Comments on D. T. Campbell's (see record 1976-12046-001) application of evolutionary theory to human social behavior and concludes that Campbell has impressively synthesized the thinking available in many fields concerning cultural evolution. However, in his analysis he has not carried certain psychological dimensions (i.e., variability, selection, retention) as far forward as information allows. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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It has now been about four years since the first impressive experience using structured programming* techniques on a large production software project.1 Yet one still hears wildly varying claims about its effectiveness in general. Here are some recent samples. 相似文献
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Four hundred seventy blood access procedures performed on 170 dialysis patients during the period 1962-1975 have been analyzed according to survival of access with respect to age, sex and cause of failure. Subcutaneous forms of blood access have a significantly longer life and are more free of complications than external shunts. Although the mode of access can now be tailored to the individual patient, the arterio-venous fistula remains the least expensive and simplest surgical procedure. It should therefore remain as the first choice of access for most patients. 相似文献
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Examined 13 research studies dealing with differences between negroes and caucasians in the validity of employment and training selection procedures. It was found that 100 of the 160 validity coefficients computed were not significant for either group, indicating the need for validation prior to operational use. Significant differences in the coefficients between groups were found only in 7 instances. Statistical significance of single group validity occurred in 33 instances. The combination of ethnic groups yielded lower validity than for either group separately on only 3 out of 120 instances. It is concluded that there is very little evidence of differential validity. Single-group validity appears linked to the use of ratings (rather than more objective criterion measures), and small samples. (25 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Y Imaiso T Taniwaki T Yamada T Yoshimura M Hirano S Ueno N Kaneda J Kira 《Canadian Metallurgical Quarterly》1998,50(2):517-519
PURPOSE: To evaluate re-treatment with an additional course of low-dose irradiation in patients with progressive or recurrent choroidal neovascular membranes (CNVMs). MATERIALS AND METHODS: Ten patients who had received 14 Gy of external-beam radiation therapy in seven fractions for subfoveal CNVMs were found to have recurrent or persistent neovascularization at follow-up. They received an additional 15 Gy of radiation therapy administered in five daily fractions with a standard lens-sparing technique. Before reirradiation, visual acuity ranged from 20/80 to counting fingers. The median time between radiation courses was 6.5 months (range, 2-16 months). After re-treatment, the patients were followed up with angiography and visual field testing. The median follow-up was 18.5 months (range, 12-21 months). RESULTS: Eight of 10 patients (80%) maintained their visual acuity at 1 year and three of seven (43%) at 18 months. Visual acuity was stabilized in five of the 10 patients at their last follow-up. No acute or late side effects of irradiation were noted. CONCLUSION: Additional radiation therapy in selected patients with CNVMs who have failed to benefit from previous irradiation is well tolerated and appears to stabilize the disease process in a substantial proportion of these patients. 相似文献
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