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61.
浆细胞病患者IL-4产生细胞数减少的意义及机制探讨 总被引:2,自引:0,他引:2
本文运用APAAP法检测了16名浆细胞患者外周血细胞在PHA刺激下产生IL-4的能力。发现浆细胞病组阳性细胞比率明显低于正常对照组(P<0.001),且阳性细胞比率与患者血清中多克隆IgM、IgA水平呈正相关(r=0.806和r=0.703)。在正常人外周血中加入CRP50mg/L,经PHA刺激后IL-4产生细胞也明显减少。作者假设,由于IL-6增高引起CRP等急性期相蛋白大量分泌,使IL-4产生受到明显抑制,从而使B细胞激活发生障碍是浆细胞病中多克隆免疫球蛋白合成抑制的主要原因。 相似文献
62.
人工心脏瓣膜置换术后患者口服抗凝治疗不当所致的出血与栓塞占远期并发症的首位。血浆凝血酶原时间(PT)是对人工心脏瓣膜置换术后患者口服抗凝药监测简便、敏感、快速、实用的实验室首选指标,其报告方式的标准化对临床医生有着非常重要的指导意义,国际标准化比率(PT-INR)作为一个较好的监测抗凝药物水平的表示方法,已被WHO推荐使用,但对于人工心脏瓣膜置换术后患者口服抗凝药治疗时PT-INR值的允许范围各地报告不一,为此,我们对我院收治的行人工心脏瓣膜置换术后患者口服华法令治疗时PT监测的情况进行了总结和研究,以探讨适合本地区人工心脏瓣膜置换术后患者口服抗凝药治疗监测中PT-INR的允许范围,为临床合理用药提供安全可靠的实验室监测指标。现报告如下。 相似文献
63.
RP—HPLC测定人血浆中洛伐他汀浓度及药动学研究 总被引:10,自引:0,他引:10
用RP-HPLC测定人血浆中洛伐他汀浓度。以甲醇-水(83∶17,V/V)为流动相,色谱柱采用HYPERSILBDS-C18(5μm)不锈钢柱,紫外237nm波长检测。血浆样品经环己烷-异丙醇(95∶5)萃取浓缩后进样测定。洛伐他汀浓度在2.5~80ng/ml范围内线性良好,r=0.9968。测定含洛伐他汀20.0ng/ml的血浆样品,其日内(n=7)及日间(n=7)的RSD分别为9.8%和8.5%。回收率平均为(101.3±5.5)%。测定了10名健康志愿者单次po洛伐他汀片剂80mg后不同时间的血药浓度,计算了相应的药动学参数。 相似文献
64.
65.
Sex differences in plasma cocaine levels and subjective effects after acute cocaine administration in human volunteers 总被引:3,自引:3,他引:0
S. E. Lukas M. Sholar L. H. Lundahl X. Lamas E. Kouri J. D. Wines L. Kragie J. H. Mendelson 《Psychopharmacology》1996,125(4):346-354
Gender differences after acute cocaine administration have received little attention in spite of the fact that males and females respond differently to many drugs. Seven male and seven female occasional cocaine users received both an intranasal dose of cocaine hydrochloride (0.9 mg/kg) and placebo powder in a randomized order and reported subjective effects via an instrumental joystick device and various questionnaires. Blood samples were withdrawn at 5-min intervals to assess pharmacokinetic differences. Male subjects achieved the highest peak plasma cocaine levels (144.4 ± 17.5 ng/ml), detected cocaine effects significantly faster than females and also experienced a greater number of episodes of intense good and bad effects. Women studied during the follicular phase of their menstrual cycle had peak plasma cocaine levels of 73.2 ± 9.9 ng/ml, which was significantly higher than when they were studied during their luteal phase (54.7 ± 8.7 ng/ml), but there were no differences in their subjective reports of cocaine effects. In spite of the different cocaine blood levels and subjective effects, peak heart rate increases did not differ between males and females suggesting that women may be more sensitive than males to the cardiovascular effects of cocaine. These data suggest that there are significant gender and menstrual cycle differences in the response to acute intranasal cocaine administration and these differences may have implications for the differential abuse of this drug.This paper is dedicated to Xavier Lamas, MD, PhD, who lost his life while ascending Mt. Everest, August 1995 相似文献
66.
Guillain-barré syndrome: A series observed at riyadh armed forces hospital january 1984–January 1994
A consecutive series of 47 hospitalized cases of Guillain-Barré syndrome seen over a 10-year period was analysed with respect
to: (1) age and sex; (2) antecedent events and seasonal distribution; (3) patterns of clinical presentation; (4) CSF and neurophysiological
findings; (5) results of treatment with plasma exchange; and (6) outcome. Twenty-two were children, 20 middle-aged and 5 aged;
37 were male and 10 were female. The most frequent antecedent event was upper respiratory tract infections; a seasonal peak
incidence was found in winter. Clinical, CSF and neurophysiological findings concurred with those in the Western literature;
79% of the cases were severe. Plasma exchange performed within the first 2 weeks of onset benefitted in the short-term outcome,
i.e. improvement by 1 grade at 4 weeks, but the long-term benefit, i.e. the ability to regain independent locomotion, was
questionable. Plasma exchange helped in curtailing the time to walking unaided but had no benefit on the duration of artificial
ventilation. Factors associated with an adverse outcome were: age over 15 years, severity of motor electrodiagnostic findings
(especially a decreased distal CMAP amplitude and EMG signs of acute denervation), requirement for ventilation and slow progression
(>3 weeks) to maximum deficit. After a mean follow-up of 11 months, 55% of the patients regained independent locomotion, which
is a comparatively low proportion. 相似文献
67.
Summary These studies were designed to determine the role of the central nervous system, the sympathetic nervous system, the adrenal glands and the renal sympathetic nerves in yohimbine-induced renin release in conscious rats. Yohimbine (0.3–10 mg/kg, s.c.) caused time- and dose-related increases in plasma renin activity (PRA) and concentration (PRC) which were accompanied by time- and dose-related elevations of plasma norepinephrine (NE) and epinephrine (Epi) concentrations. Significant positive correlations were found between the increases in PRA and the increases in plasma NE and Epi concentrations caused by yohimbine, and propranolol (1.5 mg/kg, s.c.) blocked 90% of yohimbine (3 mg/kg, s.c.)-induced renin release. Over the entire spectrum of doses of yohimbine, the increases in PRA and plasma NE and Epi concentrations were positively correlated with the decreases in mean arterial pressure (MAP), but the -intercept was positive in every case and the 1 mg/ kg dose of yohimbine consistently increased PRA independent of any change in MAP. Complete renal denervation, as evidenced by a greater than 90% reduction in renal NE content, did not alter the increase in PRA caused by yohimbine (3 mg/kg, s.c.). An increase in circulating plasma catecholamine concentrations appeared to mediate yohimbine-induced renin release since propranolol prevented the rise in PRA caused by yohimbine in renal denervated rats. Prior adrenalectomy (Adx) also failed to prevent the rise in PRA produced by yohimbine (3 mg/kg, s.c.), but a combination of Adx and renal denervation caused a significant impairment of yohimbine-induced renin release. However, neither Adx alone nor the combination of Adx and renal denervation affected the increase in plasma NE concentration caused by yohimbine. Complete transection of the spinal cord at C8 caused a drastic reduction in plasma catecholamine concentrations but did not change basal PRC. Yohimbine (3 mg/kg, s.c.) did not increase PRC or plasma catecholamine concentrations after spinal transection. Based on these results, we conclude that 1) the stimulation of renin release by yohimbine is a secondary neurohormonal consequence of the generalized increase in sympathetic activity caused by yohimbine, 2) the sympathoadrenal activation produced by yohimbine results from an action in the brain which is amplified by the simultaneous blockade of prejunctional 2-adrenoceptors and 3) vasodepressor effects of the larger doses yohimbine cause a baroreflexly-mediated increase in sympathetic activity which interacts in a positive fashion with the central and peripheral sympathoexcitatory effects of yohimbine.
Send offprint requests to T. K. Keeton 相似文献
68.
ANDREA SGOIFO SIETSE F DE BOER JOZSEF HALLER JAAP M KOOLHAAS 《Physiology & behavior》1996,60(6):1403-1407
Plasma noradrenaline (NA), adrenaline (A), and corticosterone (CS) responses to social and nonsocial stressors were studied in male members of a strain of wild-type rats, widely differing in their level of aggression. The aggressiveness was preliminarily established by measuring the latency time to attack (ALT) a male intruder in a standard resident-intruder test. Animals were then provided with a jugular vein cannula for blood sampling during stress exposure. Implanted rats were randomly assigned to 3 experimental treatments: social stress (defeat experience, SD), nonsocial stress (presentation of a shock-prod, SP) and control (animals undisturbed in their home cages, CTR). A significant correlation was found between ALT and the amount of time spent in burying the probe in SP rats: the more aggressive the animal, the higher the rate of burying behavior. SD induced a much stronger effect on plasma NA, A, and CS concentrations than SP. A significant negative correlation was found between ALT scores and values of the area under the response time curve for NA and A, in both SD and SP situations: the more aggressive the animal, the higher the catecholaminergic reactivity to the stressors. On the contrary, no evidence of a correlation between aggressiveness and plasma corticosterone responses was found, neither in SD nor in SP rats. These findings in an unselected strain of wild-type rats confirmed that an aggressive/active coping strategy is associated with a high sympathetic-adrenomedullary activation and support the concept of individual differentiation in coping styles as a coherent set of behavioral and neuroendocrine characteristics. 相似文献
69.
Changes in PG, PI and PFFA were examined and compared in fed rats or after 0 to 12 hours of fasting, during the night or during the day. At night, a progressive decrease in PG and PI and an increase in PFFA were induced by 0 to 12 hours of food deprivation. During the light period a decrease in PG occurred only from the 6th hour of fasting. A slight, progressive increase in PFFA levels was induced from 0 to 12 hours of fasting, while no significant variation of PI levels was observed. The results are discussed in terms of relationships between blood glucose, PFFA levels, and food intake in control rats over the circadian cycle. 相似文献
70.
等离子体表面改性涤纶材料的血浆蛋白吸附与血小板黏附行为研究 总被引:8,自引:0,他引:8
采用等离子体表面接枝改性技术在涤纶 (聚对苯二甲酸乙二醇酯 ,PET)材料表面接枝不同分子量的聚乙二醇 (PEG) ,从表面能与界面自由能的角度分析了血浆蛋白 (纤维蛋白原和白蛋白 )在材料表面的竞争吸附关系 ,结果表明接枝了 PEG长链分子的 PET材料具有优先吸附白蛋白的性质 ,其中接枝 PEG6 0 0 0的 PET优先吸附倾向最明显。预接触白蛋白和纤维蛋白原的 PET材料表面的血小板黏附实验表明 :吸附白蛋白的表面能够显著抑制血小板的黏附和聚集 ,表现出好的血液相容性 ,而吸附了纤维蛋白原的材料表面具有降低血液相容性的性质。 相似文献