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71.
72.
An algorythm of differential diagnosis conduction of the transplant rejection reaction and the diseases caused by herpes viruses in recipients after the kidney transplantation was elaborated, basing on the analysis of results of the clinical, laboratory, immunological and serological examination methods. 相似文献
73.
X Fang NL Weintraub CD Rios DA Chappell RM Zwacka JF Engelhardt LW Oberley T Yan DD Heistad AA Spector 《Canadian Metallurgical Quarterly》1998,82(12):1289-1297
Oxidation of LDL in the subendothelial space has been proposed to play a key role in atherosclerosis. Endothelial cells produce superoxide anions (O2.-) and oxidize LDL in vitro; however, the role of O2.- in endothelial cell-induced LDL oxidation is unclear. Incubation of human LDL (200 microg/mL) with bovine aortic endothelial cells (BAECs) for 18 hours resulted in a 4-fold increase in LDL oxidation compared with cell-free incubation (22.5+/-1.1 versus 6.3+/-0.2 [mean+/-SEM] nmol malondialdehyde/mg LDL protein, respectively; P<0.05). Under similar conditions, incubation of LDL with porcine aortic endothelial cells resulted in a 5-fold increase in LDL oxidation. Inclusion of exogenous copper/zinc superoxide dismutase (Cu/ZnSOD, 100 microg/mL) in the medium reduced BAEC-induced LDL oxidation by 79%. To determine whether the intracellular SOD content can have a similar protective effect, BAECs were infected with adenoviral vectors containing cDNA for human Cu/ZnSOD (AdCu/ZnSOD) or manganese SOD (AdMnSOD). Adenoviral infection increased the content and activity of either Cu/ZnSOD or MnSOD in the cells and reduced cellular O2.- release by two thirds. When cells infected with AdCu/ZnSOD or AdMnSOD were incubated with LDL, formation of malondialdehyde was decreased by 77% and 32%, respectively. Two other indices of LDL oxidation, formation of conjugated dienes and increased LDL electrophoretic mobility, were similarly reduced by SOD transduction. These data suggest that production of O2.- contributes to endothelial cell-induced oxidation of LDL in vitro. Furthermore, adenovirus-mediated transfer of cDNA for human SOD, particularly Cu/ZnSOD, effectively reduces oxidation of LDL by endothelial cells. 相似文献
74.
E. Ya. Litovskii F. S. Kaplan A. V. Klimovich 《Journal of Engineering Physics and Thermophysics》1978,34(3):302-304
The problem of change in thermal resistance of pores and microcracks in refractories with occurrence of heterogeneous reactions and formation of gas with diffusion product transfer in the temperature gradient field is analyzed.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 34, No. 3, pp. 452–455, March, 1978. 相似文献
75.
A new three dimensional oscillator for generating three phases of sinewaves is derived. The model is similar to the previous ones (Ref. 1 and 2) in enabling an undistorted stabilized generation of sinewaves. It possesses certain advantages in comparison to the previous models. The oscillator appears as a viable model for representing synchronous generators in a simplified manner in the simulation of power systems. 相似文献
76.
77.
PJ Hofschire EP Todd RL Varco EL Kaplan JE Edwards 《Canadian Metallurgical Quarterly》1976,69(3):439-440
We report an unusual case in which an apparently normal upper lobe of the right lung was supplied by major systemic arterial and pulmonary arterial vessels. The anomalous artery arose from the descending aorta. Following interruption of this vessel, the machinery-like murmur previously present disappeared. 相似文献
78.
79.
Rohsenow Damaris J.; Monti Peter M.; Hutchison Kent E.; Swift Robert M.; MacKinnon Selene V.; Sirota Alan D.; Kaplan Gary B. 《Canadian Metallurgical Quarterly》2007,15(1):81
Although treatment with transdermal nicotine replacement (TNR) has improved smoking abstinence rates, higher doses of TNR could improve effects on urge to smoke, nicotine withdrawal, and reinforcement from smoking, and naltrexone might further reduce reinforcement and urges. A laboratory investigation with 134 smokers using a 3 × 2 parallel-group design evaluated the effects of TNR (42-mg, 21-mg, or 0-mg patch) as crossed with a single dose of naltrexone (50 mg) versus placebo on urge to smoke, withdrawal, and responses to an opportunity to smoke (intake, subjective effects) after 10 hr of deprivation. Urge and withdrawal were assessed both prior to and after cigarette cue exposure. Only 42 mg TNR, not 21 mg, prevented urge to smoke, heart rate change, and cue-elicited increase in withdrawal. Both 21 and 42 mg TNR blocked cue-elicited drop in heart rate and arterial pressure. Naltrexone reduced cue-elicited withdrawal symptoms but not urges to smoke or deprivation-induced withdrawal prior to cue exposure. Neither medication significantly affected carbon monoxide intake or subjective effects of smoking except that 42 mg TNR resulted in lower subjective physiological activation. No interaction effects were found, and no results differed by gender. Results suggest that starting smokers with 42 mg TNR may increase comfort during initial abstinence, but limited support is seen for naltrexone during smoking abstinence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
Silk fibers have been used in textiles for more than 5,000 years and as a suturing material for many centuries. The recent development of new applications for silks include drug delivery. An overview of this new field is provided, summarizing the development of emerging drug delivery applications which include silk-based nanomedicines and transdermal delivery systems We also highlight some of the challenges in developing silk-based drug delivery systems. 相似文献