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51.
Postischemic renal dysfunction: the limited role of xanthine oxidase-generated oxygen free radicals 总被引:1,自引:0,他引:1
Oxygen free radicals (OFRs) generated during reperfusion are putative mediators of postischemic renal dysfunction. To address this issue, the renal response to ischemia and reperfusion was compared to the response to OFR generation without ischemia. Isolated rat kidneys were perfused at 37 degrees C and 90-100 mm Hg with an asanguinous modified Krebs' buffer. Kidneys were subjected to 30 min of ischemia followed by reperfusion or to OFRs generated by combining 25 mumole hypoxanthine with 1 unit xanthine oxidase. Both insults caused a 50% increase in vascular resistance. This was accompanied by a 30% reduction in perfusate flow rate and an 80% reduction in glomerular filtration and urine flow rates. The OFR scavengers, superoxide dismutase (SOD, 250 units/ml) and catalase (CAT, 500 units/ml), prevented these alterations after OFR generation but not after 30 min of ischemia and reperfusion. SOD and CAT also afforded no protection against the less severe dysfunction observed after 10 or 20 min of ischemia and reperfusion. OFRs do not appear to be prominent mediators of postischemic renal dysfunction; other factors, probably associated with ischemia must be primarily responsible. 相似文献
52.
53.
D J Flournoy M C Robinson 《Methods and findings in experimental and clinical pharmacology》1990,12(8):541-544
Three hundred and forty-nine methicillin resistant Staphylococcus aureus (MRSA) isolates from veterans were tested (by disc agar diffusion) for their in vitro activity against 18 antimicrobial agents. At least 90% of the isolates were susceptible to bacitracin, nitrofurantoin, hydrogen peroxide, novobiocin, netilmicin and vancomycin. We feel that the aminoglycoside, netilmicin, might provide an alternative agent (to intravenously administered vancomycin) for treating multiply-antimicrobial resistant MRSA. In addition, hydrogen peroxide exhibited very good activity against the test isolates and may have some use as a topical agent for reduction of MRSA on skin and some mucous membranes. This study suggests that further evaluation of netilmicin and hydrogen peroxide (topical only) might be useful. 相似文献
54.
Choc Miles G. Hsuan Francis Honigfeld Gilbert Robinson William T. Ereshefsky Larry Crismon Miles L. Saklad Stephen R. Hirschowitz Jack Wagner Richard 《Pharmaceutical research》1990,7(4):347-351
Clozapine plasma levels were monitored in 16 patients during a series of three consecutive treatments (single dose-multiple dose-single dose). Each patient received a single 75-mg dose (3 x 25 mg) with clozapine tablets, and serial plasma samples were collected over 48 hr after the dose. At 48 hr, a multiple-dose regimen was started, consisting of an initial dose escalation period followed by dosing at a constant regimen for at least 6 days. After the last dose, serial plasma samples were again obtained over 72 hr. Drug was then withheld for at least 7 days, a final single 75-mg dose was given, and plasma sampling was repeated. A subset of the patient population (N = 7) was used to test for a food effect during the single-dose treatments. The pharmacokinetic parameters between the initial and the final single dose periods were not significantly different. Similarly, there were no differences within patients when given the dose after fasting (fed 1 hr after dose) or with a meal. In contrast, the terminal elimination rate differed between the single-dose and the multiple-dose treatments (t1/2 m3 = 7.9 hr single dose and 14.2 hr multiple dose) (P less than 0.05) and the dose-normalized area under the plasma concentration/time curves increased 27% with multiple dosing. Since a previous study in patients (Choc et al., Pharm. Res. 4:402-405, 1987) showed dose proportionality of clozapine plasma concentrations during multiple-dose regimens, the present results cannot be described by Michaelis-Menten kinetics. 相似文献
55.
56.
在海拔3417m对18名健康世居藏族和16名移居汉族用Jeager气体代谢自动分析系统和心阴抗图测定了无氧阈和最大摄氧量时的SV、CO、PEP/LVET和SaO2。结果显示:在海拔3417m测得AT值明显低于海平面;世居藏族AT出现较晚,并且AT时的功率、VO2、MV、HR、CO、SV均高于移居汉族,而PET/LVET比值小于移居组;两组的SV峰值出现时间不同,蕊居组在AT或AT以后出现的占72% 相似文献
57.
Current methods of predicting prognosis in transitional cell carcinoma of the bladder fail to provide consistently reliable information about future tumour behaviour. The monoclonal antibody Ki67 recognises an antigen present in actively dividing cells and Ki67 reactivity has been shown to correlate with conventional prognostic indicators in several tumours. In this study, Ki67 antibody was used to determine the proportions of cells undergoing active division in 26 transitional cell carcinomas of the bladder. The proportion of cells stained in muscle invasive tumours (12.3 +/- 5.4%) was significantly greater than in superficial tumours (4.3 +/- 1.9%) and poorly differentiated tumours showed significantly greater proportions of cells staining compared with well or moderately well differentiated tumours. These results show that Ki67 reactivity correlates with high tumour stage and poor differentiation. Ki67 staining provides an easy method of determining tumour cell turnover that might provide additional prognostic information. 相似文献
58.
护士礼仪课的教学与实践 总被引:4,自引:0,他引:4
为适应医学模式的转变和市场需求,福建中医学院护理学系开设护士礼仪选修课,并对此课程进行教学设计,包括师资培养设计、教学对象设计、教学内容设计、教学方法设计。在授课结束对学生问卷调查、访谈和考试,并对结果进行统计学处理.认为教学实践效果较好。另在教学实践基础上讨论开设护士礼仪课程的意义,提出护士礼仪课程建设若干思考。 相似文献
59.
60.
体外培养诱导外周血淋巴细胞促进大鼠面神经再生的实验研究 总被引:1,自引:0,他引:1
目的:通过在神经缺损处局部回输体外分离培养纯化的淋巴细胞,了解此种方法促进面神经损伤修复的效果。方法:将20只Wistar大鼠的面神经颊支剪断并立即缝合(其余3支反折缝合)制成面神经损伤模型大鼠,将其分成淋巴细胞组和对照组,每组10只,每组再分成2周组和8周组。淋巴细胞组局部回输体外分离培养的外周血淋巴细胞,对照组作对照。于2周和8周测定面神经颊支-触须肌复合动作电位传导速度,辣根过氧化物酶(HRP)神经逆行示踪测定面神经核团的神经元阳性数目。结果:淋巴细胞组面神经颊支-触须肌复合动作电位传导速度8周时为0.64±0.07,与对照组(0.56±0.07)相比,差异有统计学意义(P<0.05)。HRP神经逆行示踪测定面神经核团神经元阳性数目,淋巴细胞组2周及8周与对照组同时间段相比差异均无统计学意义(均P>0.05)。结论:体外分离培养纯化的淋巴细胞在局部应用于神经损伤处对面神经再生修复可起一定的促进作用。 相似文献