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31.
Idiopathic or congenital coronary artery ectasias and aneurysms are uncommon forms of coronary artery disease. The prognosis and optimal management of such patients remains unknown. The authors describe the case of an otherwise healthy 30-year-old man with concomitant severe right coronary artery ectasia and left main coronary artery aneurysm who sustained a mild anterior myocardial infarction. There was no obstructive coronary artery disease, and no cause for the lesions could be identified. Chronic anticoagulation and antiplatelet therapy were initiated with resolution of symptoms. 相似文献
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MS Huang CS Lai IW Chong MS Lin MS Tsai HC Lin JJ Hwang 《Canadian Metallurgical Quarterly》1996,90(6):343-348
To establish the spirometric values for normal, healthy Chinese women in Taiwan, the spirometry of 506 life-long non-smoking, healthy Chinese women was examined, including 140 subjects over the age of 60 years. Significant correlations among age, height and forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC%, peak expiratory flow (PEF), Vmax75, Vmax50, Vmax25 were found. However, there were no significant correlations between age and FEV1/FVC%, nor age and Vmax25 in the elderly group. FEV1 (FEV1*) and FVC (FVC*) were standardized to the overall mean height for elderly women using Cole's formula. The decline in FEV1* and FVC* with age were observed. The predicted value for the average 70-year-old woman with a height of 1.5 m derived from the present study is compared with those from other surveys of the elderly. The values from the present study are somewhat higher than the values from the Hong Kong study. The authors believe the fact that all of the present subjects were life-long non-smokers might explain the differences. 相似文献
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1. The binding of cholic acid to 100000g supernatants from rat livers was investigated by equilibrium dialysis and gel-exculsion chromatography. 2. Supernatants were found to contain at least two classes of binding site for cholic acid. 3. These recptor molecules are probably proteins since incubation with proteolytic enzymes resulted in complete loss of cholic acid binding. 4. Supernatants were added to columns of Sephadex G-75, and two groups of fractions were shown to bind cholic acid. One of these contained low-affinity binding sites and the other contained both low- and high-affinity binding sites. 5. Feeding cholestyramine had no effect on cholic acid binding. 6. Increased cholic acid binding occurred after injection of phenobarbitone. There was an increase in the amount of the low-affinity component but no change in the high-affinity component. 7. The dissociation constants of the binding of cholic acid suggest that the binding proteins may be involved in bile acid transport. 相似文献
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IW Campell 《Canadian Metallurgical Quarterly》1976,30(6-8):153-156
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Nonsampling errors are subtle, and strategies for dealing with them are not particularly well known within psychology. This article provides a compelling example of an incorrect conclusion drawn from a nonrandom sample: H. C. Lombard's (1835) mortality data. This example is augmented by a second example (A. Wald, 1980) that shows how modeling the selection mechanism can correct for the bias introduced by nonsampling errors. These 2 examples are then connected to modern statistical methods that through the method of multiple imputation allow researchers to assess uncertainty in observational studies. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
39.
A rat liver microsome pseudostationary phase has been used for the on-line capillary electrophoresis monitoring of glucuronidation. Uridine diphosphate glucuronosyltransferase (EC 2.4.1.17) containing microsomes was isolated from rat liver and directly injected onto neutrally coated capillary containing polymeric replaceable gels followed by injection of the substrate mixture. On-line glucuronidation was observed within 15 min without any sample preparation. The factors affecting the separation of glucuronides and parent compounds were investigated by varying the applied electric fields and the size (length and internal diameter) of capillary. The Michaelis-Menten parameters (Km and Vmax) for the glucuronidation of 4-methyl-7-hydroxy coumarin and 4-nitrophenol were determined using the CE method and by off-line microsomal incubation. No significant differences were observed for Km and Vmax values for 4-methyl-7-hydroxycoumarin and 4-nitrophenol between on-line and off-line glucuronidation of these two compounds. This method was also used to determine the inhibition constant (IC50 value) for the competitive inhibition of morphine glucuronidation by codeine, IC50 (on-line) = 170 vs 580 microM (off-line). The results demonstrate that this method can be used to screen for the glucuronidation of test compounds and should reduce the time required for this screening process. 相似文献
40.
Correlations between bibliometrics and peer evaluation for all disciplines: the evaluation of Brazilian scientists 总被引:1,自引:0,他引:1
This paper correlates the peer evaluations performed in late 2009 by the disciplinary committees of CNPq (a Brazilian funding agency) with some standard bibliometric measures for 55 scientific areas. We compared the decisions to increase, maintain or decrease a scientist’s research scholarship funded by CNPq. We analyzed these decisions for 2,663 Brazilian scientists and computed their correlations (Spearman rho) with 21 different measures, among them: total production, production in the last 5 years, production indexed in Web of Science and Scopus, total citations received (according to WOS, Scopus, and Google Scholar), h-index and m-quotient (according to the three citation services). The highest correlations for each area range from 0.95 to 0.29, although there are areas with no significantly positive correlation with any of the metrics. 相似文献