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991.
该文叙述了表面形貌的数学模型;分析了表面接触的力学过程;文章还阐述了部分EHL的形成原理并介绍了表面摩擦学行为的观察分析技术。 相似文献
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苏武的思想曾受儒、释、道3家的影响。游览赤壁的3篇诗文反映了苏轼由主儒思想向主道思想转变的过程。 相似文献
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997.
讨论非线性脉冲时滞差分方程:{xn 1-xn Pnf(Xn-l)=0,n≥0,n≠nk,xnk 1-xnk=bkxnk,k=1,2,3……给出了一类f方程所有解振动的充分条件。 相似文献
998.
主要利用Gronwall-Bellman -Behari不等式 ,把一类二阶线性微分方程与其摄动方程进行比较 ,对摄动项作适当限制 ,得到一类非线性非齐次微分方程属于极限圆型的判定准则 相似文献
999.
The present study was undertaken to clarify the pathogenesis of cisplatin-induced acute renal failure at the early stage.
Male Sprague-Dawley rats were given an intravenous administration of 10 mg/kg cisplatin. 0.9% saline was infused into them
at a rate of 2 ml/h for 3 h, starting with a 2-ml bolus injection before cisplatin administration. 3 h following cisplatin
administration, no evident morphological abnormalities were found by both light and electron microscopy; there were also no
significant changes in GFR. Thirty min after cisplatin injection, urine sodium and potassium excretion increased by 56% and
260% those of the control animals, respectively. Apparent renal mitochondrial respiration dysfunction was observed in cisplatintreated
rats 3 h later; the state 4 respiration increased by 100% and state 3 respiration, respiratory control ratio and carbonyl
cyanide p-trifluoromethoxyphenyl hydrazone-uncoupled respiration decreased by 46%, 74% and 47% of the controls, respectively.
The present data suggest that mitochondrial dysfunction may be a very early event in cisplatin-induced acute renal failure
in rats. 相似文献
1000.
This study was carried out to elucidate the nephroprotective effects from a mixture of 8 L-amino acids and the possible mechanism
of protection by this amino acid mixture. Acute renal failure model was induced by an intravenous administration of 10 mg/kg
cisplatin to male Sprague-Dawley rats. A mixture of 8 L-amino acids or 0.9% saline was infused at a rate of 2 ml/h for 3 h,
starting with a 2 ml bolus injection before cisplatin administration. Amino acids showed no acute effect on renal morphology.
The infusion of a mixture of 8 L-amino acids increased GFR by 85% in control rats. The abnormalities of urine sodium and potassium
excretion caused by cisplatin were markedly attenuated by the administration of the amino acid mixture. With the infusion
of this amino acid mixture, cisplatin-induced abnormal state 4 respiration returned to control levels and the depressed state
3 respiration, respiratory control ratio and carbonyl cyanide p-trifluoromethoxyphenyl hydrazone-uncoupled respiration were
ameliorated remarkably. A mixture of 8 L-amino acids showed marked nephroprotection against cisplatin-induced acute renal
failure in rats and might function through augmentation of the cisplatin-injured renal mitochondrial electron transport-oxidative
phosphorylation sequence, probably via stabilizing the membrane (including inner mitochondrial membrane) protein tertiary
structure. In addition, this amino acid mixture remarkably increased GFR and decreased urine sodium excretion in rats. 相似文献