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1.
The Flinders Sensitive Line (FSL) of rats has been selectively bred to have increased sensitivity to cholinergic agonists. However, these rats exhibit altered responsiveness to a number of noncholinergic agents, such as apomorphine, buspirone and ethanol. This study compared the FSL and control Flinders Resistant Line (FRL) rats in terms of their hyperthermic response to the phencyclidine (PCP) receptor agonist, MK-801 (0.2 mg/kg SC) and their MK-801 binding characteristics. We have found that FSL rats react with a delayed hyperthermia, having a significantly lower hyperthermia for the first 120 min of observation. Thereafter the response does not differ in FSL and FRL rats. Both groups had similar affinities and numbers of [3H]MK-801 binding sites in the hippocampus/cerebral cortex. Pretreatment with scopolamine (1 mg/kg SC) failed to affect MK-801-induced hyperthermia in either line of rats. These findings suggest that selective breeding of FSL rats attenuated the secondary mechanisms involved in the PCP receptor-mediated hyperthermic response. However, by itself cholinergic supersensitivity does not appear to be a major factor in the blunted responsiveness of FSL rats to MK-801.  相似文献   
2.
目的 探讨体外循环(CPB)术中发生冷凝集试验阳性的处理经验。方法 采用最适宜的温度(鼻咽温31.5℃—32.5℃,肛温34℃~35℃),常温高钾停跳液,CPB大剂量抑肽酶和皮质激素的应用及激活全血凝血时间(ACT)的严格监测等等。结果 术中阻断主动脉65min,心脏自动复跳,术后无中枢神经系统并发症及血红蛋白尿。结论对CPB术中发生冷凝集试验阳性的病人采取综合性的防救措施可以有效的防止红细胞凝集、溶血等不良反应,确保手术安全。  相似文献   
3.
随着医学事业的发展,监护仪得到广泛的运用,就医用监护仪常用生理参数的工作原理简述如下。  相似文献   
4.
The neuroendocrine and clinical effects of transdermal 17β-estradiol (rated at 50 μg/day; TTS 50) were studied in 40 postmenopausal women; ten additional postmenopausal women did not receive any drugs. The changes in LH and rectal temperature induced by the infusion of the opioid antagonist naloxone (10 mg i.v. bolus plus 10 mg/h for 4 h) were used to evaluate the central activity of endogenous opioid peptides. TTS 50 increased opioid activity, as evidenced by the restoration of the LH response (P < 0.01) and the enhancement of the hypothermic effect (P < 0.05) of naloxone. A greater reduction in hot flushes was observed in TTS 50-treated subjects than in untreated women, with the maximal effect of TTS 50 achieved after 3 months of therapy. TTS 50 did not modify the concentrations of circulating lipids, glucose or liver enzymes but reduced the biochemical parameters indicative of bone reabsorption. Bone density of the distal radius significantly increased during TTS 50 (P < 0.02), reaching its maximum value after 6 months of therapy. Thereafter bone density declined, but more slowly than in untreated women.

Our data suggest that TTS 50 has marked neuroendocrine effects, that it diminishes the incidence of hot flushes and reduces bone demineralization. By contrast, it has a very little, if any, metabolic impact on the liver or on glucose and lipid metabolism.  相似文献   

5.
目的探讨温度、抗凝剂(EDTA-K2)对血嗜酸性粒细胞阳离子蛋白(ECP)水平的影响。方法采用固相双位点酶放大化学发光法,分别对22例健康体检者在两种不同温度(25℃和37℃)的血清标本,以及在相同温度(37℃)下,加抗凝剂和不加抗凝剂的血标本进行ECP水平测定。结果25℃组和37℃组血清ECP水平分别为8.92±6.45μg/L(x±s)和19.87±12.16μg/L(x±s),两组有显著性差异(P<0.01);37℃温度下加抗凝剂和不加抗凝剂血标本的ECP水平分别为5.26±2.60μg/L(x±s)和19.87±12.16μg/L(x±s),两组也有显著性差异(P<0.001)。结论温度和抗凝剂(EDTA-K2)对血标本的ECP水平测定有不同程度的影响。  相似文献   
6.
We retrospectively reviewed the records of 250 consecutive patients undergoing coronary artery bypass graft surgery (CABG) from January 1994 through January 1996 to determine the incidence of persistent postoperative neurological dysfunction after CABG and to compare normothermic and moderate hypothermic cardiopulmonary bypass (CPB). Normothermic CPB was used in 128 patients (36°–37°C) and hypothermic CPB (27°–28°C) in 122 patients. Postoperative neurological dysfunction included focal motor deficits, delayed recovery of consciousness (>24h) after surgery, and seizures within 1 week postoperatively. Persistent neurological dysfunction was diagnosed if complete resolution had not occurred within 10 days of surgery. The incidence of persistent postoperative neurological dysfunction was 4.1% in the hypothermic CPB group and 2.3% in the normothermic CPB group. There were no statistically significant differences between the two groups (P=NS). These results suggest that normothermic CPB did not increase the incidence of persistent postoperative neurological dysfunction compared to hypothermic CPB.  相似文献   
7.
不同针刺手法调节体温效应机制研究概况   总被引:8,自引:2,他引:6  
季淑梅  阎丽 《中国针灸》2007,27(4):306-308
目的:介绍近年不同的针刺手法对体表温度调节效应的研究,并探讨其产生体温效应的机制。方法:从临床研究、实验研究等方面进行综述。结论:针刺穴位的作用及其疗效,随着手法引起的温度变化而不同,针刺补法引起体温升高,而泻法则引起体温下降。体表温度是由血液循环状态、交感神经兴奋程度和组织新陈代谢状态等多方面决定的,不同的针刺手法引起的皮肤温度变化与影响上述3个环节状态有关。  相似文献   
8.
Temperature sensitive liposomes (TSL) containing adriamycin (ADM) and cytarabine (Ara-C) were prepared. ADM and Ara-C were selected as model compounds of amphiphilic and hydrophilic drug, respectively. Encapsulation efficiency of ADM entrapped into TSL was about twice greater than that of Ara-C. It might be due to different polarity of the drugs. Lipid compositions of TSL had no effect on the encapsulation efficiency of drugs. Thermal behavior of TSL using a differential scanning calorimetry (DSC) was also investigated. Phase transition temperature (Tc) of TSL was dependent on the lipid compositions of TSL.ADM broadened thermogram of TSL but Ara-C did not. However, Tc of TSL was not changed by any drug. Release rate of drugs was highly dependent on temperature. The release profile of ADM was similar to that of Ara-C. The maximum release rate of drugs from TSL was occurred at the near Tc and observed at 39–41°C for DPPC (Dipalmitoylphosphatidylcholine) only, 52–54°C for DSPC (Distearoylphosphatidylcholine) only, 41–43°C for DPPC and DSPC (3∶1), and 43–45°C for DPPC and DSPC (1∶1), respectively. Effect of human serum albumin (HSA) on the release rate of ADM was investigated. HSA had no significant effect on the release of ADM below Tc. However, ADM release from TSL was increased at the near and above Tc. The HSA-induced leakage of drug may result from the interaction of liposomal constituents with HSA structure at the near Tc. From the fact that the release profiles of ADM from freshly prepared TSL and stored TSL for 1 week at 4°C was not changed, the TSL was considered to be stable for at least 1 week at 4°C. Based on these findings, TSL may be useful to deliver drugs to preheated target sites due to its thermal behaviors.  相似文献   
9.
目的 研究高温高湿环境下颅脑火器伤后生命体征变化特点及死亡因素。 方法 杂种猫 3 2只随机分为 4组 ,火器伤后分别放入A (2 5℃、相对湿度 50 % )、B (3 5℃、相对湿度85% )、C(3 8℃、相对湿度 90 % )、D(40℃、相对湿度 95% )四种环境中。每隔 10min记录一次血压、脉搏、呼吸频率及体温 ,到 6h时结束实验。 结果 常温枪伤组实验过程中生命体征稳定 ,随着温度及湿度的增加 ,各组动物相同时相点的体温、呼吸及心率均明显不同 (P <0 .0 5)。A组、B组动物在伤后 6h内均无死亡。C组 1.5h开始死亡 ,至 5h动物全部死亡 ,平均生存时间为 3 .4h。D组 0 .5h开始死亡 ,至 2 .5h动物全部死亡 ,平均生存时间为 2 .0h。 结论 高温高湿环境对颅脑火器伤时的生命体征变化和死亡率影响显著  相似文献   
10.
本文对12例体表恶性肿瘤病人采用放射治疗与微波加热治疗并用的方法取得了较好的效果,总有效率100%。  相似文献   
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