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991.
Skin penetration of topically applied diclofenac is important for the treatment of rheumatic diseases and actinic keratoses. We have studied the permeation of diclofenac across human cadaver epidermis in-vitro from four lecithin vesicle formulations and a few marketed semi-solid preparations. The lecithin vesicle formulations were prepared by dissolving the lipid contents (lecithin and sodium cholate) in a 1:1 mixture of methanol-chloroform, evaporating the solvents under vacuum, and hydrating the lipid layer with the drug solution in water or 10% ethanol. The vesicles were sonicated for 5 min to reduce the vesicle size and their size and Zeta potential were characterized. The cumulative amount and maximum flux of diclofenac was 69.7+/-40.3 micrograms and 4.77+/-3.16 micrograms/hcm(2) from lecithin vesicles containing sodium cholate and 10% ethanol, and is the highest of all formulations studied. The cumulative amount and mean maximum flux obtained from other formulations were in the range of 2.46+/-1.98-29.9+/-10.1 micrograms and 0.53+/-0.46-3.61+/-0.86 micrograms/hcm(2). Based on the results, lecithin vesicles of diclofenac appear to be advantageous for the topical delivery of diclofenac.  相似文献   
992.
PURPOSE: To investigate the corneal and scleral permeability of nalidixic acid and synthesized fluoroquinolones and their in vivo pharmacokinetics in rabbits. METHODS: The corneal and scleral permeability coefficients of ciprofloxacin, norfloxacin, cinoxacin, enoxacin, and ofloxacin were determined in rabbits using high performance liquid chromatography (HPLC). The aqueous humor levels of norfloxacin and ciprofloxacin were measured separately by topical instillation of 0.3% solutions of the two drugs onto rabbit eyes. RESULTS: Nalidixic acid had a higher corneal permeability coefficient (17.3 +/- 3.56 x 10(-6) cm/second) than all other drugs tested (p < 0.01). Corneal permeability coefficients in rabbits among ciprofloxacin, norfloxacin, cinoxacin, enoxacin, and ofloxacin were not significantly different (p > 0.1). Comparing the corneal and scleral permeability coefficients, only values for nalidixic acid were not significantly different (17.35 +/- 3.56 x l0(-6) cm/second versus 22.69 +/- 5.19 x 10(-6) cm/second, p > 0.05), while all other drugs had scleral permeability coefficients 8 to 10 times greater than corneal permeability coefficients. The mean aqueous humor concentration of norfloxacin and ciprofloxacin at 60 minutes to 180 minutes after instillation was around 0.3 microg/mL, a value higher than MIC90 of most bacteria.  相似文献   
993.
目的 观察葛根素对糖尿病周围神经病变的临床疗效。方法 在治疗糖尿病的同时 ,用0 9%氯化钠注射液 30 0mL 葛根素 0 4g静脉滴注 ,每天 1次 ,10d为 1疗程 ,共 3个疗程。结果 用葛根素治疗糖尿病周围神经病变 5 3例 ,显效 31例 ,有效 12例 ,总有效率达 81% ,无明显副作用。结论 葛根素治疗糖尿病周围神经病变效果较好 ,副作用小 ,值得推广运用  相似文献   
994.
Objective. To assess the feature of pulmonary blood flow distribution after total cavopulmonary connection (TCPC) of different types, and to provide the selection of the best type .Methods. Thirty-two consecutive survival patients after TCPC underwent radionuclide lung perfusion imaging. According to the radionuclide counts in the left and right lungs, analyses of the distribution of blood flow from superior venous cava (SVC) and inferior venous cava (IVC) and the whole pulmonary blood flow in both lungs were made. All patients were divided into 4 groups by the the anastomosis between IVC and pulmonary artery.Results. Group Ⅰ: The flow ratio of the IVC to left lung was greater than that to the right lung , P≤0. 01; the flow ratio of the SVC to right lung was greater than that to the left lung, P≤0. 01; and the whole pulmonary blood flow went dominantly to the left lung, P≤0. 05, which is not in line with physiological distribution. Group Ⅱ: the flows from the SVC and IVC were mixed in the middle of  相似文献   
995.
In certain Japanese macaque (Macaca fuscata) populations, females routinely engage in same-sex courtship, mounting, and consortship activity. Drawing on behavioral, biogeographic, and genetic research, we suggest that female homosexual behavior may be associated with genetically distinct free-ranging populations of Japanese macaques. In addition, we briefly discuss the implications of this research for the evolution of female homosexual behavior in this species.  相似文献   
996.
piRNA(Piwi—interacting RNA)是2006年发现的一种新的小RNA,长度约24到30个核苷酸,其作用与Dicer酶无关.与Piwi蛋白家族成员相结合才能发挥作用。目前研究piRNA的功能都基本限定在生殖细胞中,近来研究表明piRNA对于生殖细胞功能的很多环节有巨大的影响,而且对生殖支持细胞的影响的研究也有了进展。本文就piRNA在生殖系统中的功能的研究进展作一综述。  相似文献   
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体育游戏是小学体育教学的重要内容,是教育学生最好的方法之一。我国现代著名教育家陈鹤琴先生说过:"小孩生来是好动的,是以游戏为生命的。"毛泽东同志在给《新体育》一书的题词中写道:"要活动,要游戏,是儿童的天性。"这充分说明了学生对游戏有着特殊的感情。  相似文献   
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