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81.
目的研究加兰他敏对阿尔茨海默病(AD)大鼠认知功能的影响及NMDA受体在其中的作用。方法雄性SD大鼠65只,随机分为假手术、链脲菌素(STZ)组,加兰他敏、MK-801和犬尿烯酸3个治疗组。侧脑室注射STZ制备大鼠AD模型,水迷宫试验测定大鼠的学习记忆能力。3个治疗组分别给予加兰他敏、MK-801 加兰他敏、犬尿烯酸 加兰他敏,共6周。结果术后第10天各组潜伏期明显延长,过平台次数明显减少,差异均无统计学意义。治疗6周后加兰他敏组潜伏期缩短,过平台次数增加,与STZ组比较,有显著差异,而MK-801和犬尿烯酸组潜伏期和过平台次数与STZ组比较,无明显差异。结论加兰他敏对AD大鼠的认知功能具有明显的改善作用,而应用NMDA受体阻断剂后其治疗作用消失。说明NMDA受体介导了加兰他敏对AD大鼠认知功能的改善。 相似文献
82.
本文应用日本血吸虫虫卵单克隆抗体及虫卵可溶性抗原,分别致敏新型免疫微球载体重氮基聚苯乙烯乳胶,制备出血吸虫反向乳凝试剂与乳凝试剂,并用于检测血吸虫病患者血清标本中的相应抗原和相应抗体,以此试验检测197份急慢性血吸虫病患者血清标本。结果反向乳凝试剂检出率为90.4%,乳凝试剂检出率为95.2%,均高于反向间接血凝法的85.0%。反向乳凝试验与乳凝试验联合应用,既可早期诊断,又可判断疗效。试验采用玻片凝集法,3min内即出结果,方法敏感.特异、简便和快速。 相似文献
83.
84.
Da-Nian Zhu, Long-Mei Xue, Peng Li. Effect of central muscarine receptor blockade. with DKJ-21 on the blood pressure and heart rote in stress-induced hypertensive rats.
The experiments were performed on Wistar or Sprague-Dawley rats of both sexes divided at random into stress and control groups. The rats in the stress groups were put into cages and subjected to electric foot-shocks and noises for 9-15 days, which caused an increase in blood pressure (BP) and heart rate (HR). In hypertensive rats DKJ-21 (4mg/lml) was injected intravenously (i.v.), and 0.5-1.0h after administration the BP and HR dropped from the high level to normotensive level. In normotensive rats, however, administration of DKJ-21 had no effect on BP or HR. In separate groups of normotensive rats, pretreatment of DKJ-21 (4 mg/l ml, i.v.) blocked the pressor and tachycardiac effect induced by microinjection of physostigmine (0.4μg/0.1 /μl/site), corticosterone (40μg/0.1μl/site) or aldosterone (40 μg/0.1 μl/site) into the rostral ventrolateral medulla (rVLM). Furthermore, DKJ-21 also attenuated the enhancement of the pressor response to stimulation of the defense area in the midbrain, which was induced by microinjection of drugs (mentioned above) into the rVLM. These results indicate that i.v. DKJ-21 can selectively block the muscarinic receptors in the rVLM in stress-induced hypertensive rats, which suggests that abnormal enhancement of cholinergic mechanism in the rVLM may be related to hypertensive effects of corticoids in this area. 相似文献
The experiments were performed on Wistar or Sprague-Dawley rats of both sexes divided at random into stress and control groups. The rats in the stress groups were put into cages and subjected to electric foot-shocks and noises for 9-15 days, which caused an increase in blood pressure (BP) and heart rate (HR). In hypertensive rats DKJ-21 (4mg/lml) was injected intravenously (i.v.), and 0.5-1.0h after administration the BP and HR dropped from the high level to normotensive level. In normotensive rats, however, administration of DKJ-21 had no effect on BP or HR. In separate groups of normotensive rats, pretreatment of DKJ-21 (4 mg/l ml, i.v.) blocked the pressor and tachycardiac effect induced by microinjection of physostigmine (0.4μg/0.1 /μl/site), corticosterone (40μg/0.1μl/site) or aldosterone (40 μg/0.1 μl/site) into the rostral ventrolateral medulla (rVLM). Furthermore, DKJ-21 also attenuated the enhancement of the pressor response to stimulation of the defense area in the midbrain, which was induced by microinjection of drugs (mentioned above) into the rVLM. These results indicate that i.v. DKJ-21 can selectively block the muscarinic receptors in the rVLM in stress-induced hypertensive rats, which suggests that abnormal enhancement of cholinergic mechanism in the rVLM may be related to hypertensive effects of corticoids in this area. 相似文献
85.
86.
CT导引下肝肾囊肿抽吸硬化治疗 总被引:6,自引:0,他引:6
目的:总结CT导引下肝肾囊肿穿刺抽吸硬化治疗的疗效和操作经验。材料和方法:肝囊肿11,肾囊肿15例,多囊肾1例,囊肿大小为3.5-12cm,均用15cm长20GGreene针穿刺治疗,抽出囊液量为21-550ml,囊液抽净后注入99.7%的无水酒精。结果:治疗后症状均有明显好转或消失,本组随访肝囊肿7例、肾囊肿11例,疗效指数I级1例(多囊肾),Ⅱ级肝肾囊肿各2例,Ⅲ级肝囊肿5例肾囊肿8例。穿刺操作顺利,无严重并发症发生。结论:CT导引下肝肾囊肿抽吸硬化治疗操作简便、创伤小、疗效高可作为替代外科手术的有效的治疗方法,多囊肾的单纯抽吸治疗可明显减轻症状,改善肾功能,是一种较好的治疗手段。 相似文献
87.
88.
Replacement of cholesterol gallstones by murideoxycholyl taurine gallstones in prairie dogs fed murideoxycholic acid 总被引:1,自引:0,他引:1
B I Cohen N Ayyad E H Mosbach C K McSherry N Matoba A F Hofmann H T Ton-Nu Y Peng C D Schteingart R J Stenger 《Hepatology (Baltimore, Md.)》1991,14(1):158-168
The effect of two hydrophilic bile acids, murideoxycholic acid (3 alpha,6 beta-dihydroxy-5 beta-cholanoic acid) and ursodeoxycholic acid, on cholesterol and bile acid metabolism and hepatic pathology and gallstone composition was studied in the prairie dog. Cholesterol gallstones were induced by feeding a diet containing 1.2% cholesterol for 75 days. The animals were divided into six groups, and gallstone regression was studied as follows: groups 2 and 5, chow plus 0.2% cholesterol; groups 3 and 6, chow plus 0.2% cholesterol plus 0.15% ursodeoxycholic acid; groups 4 and 7, chow plus 0.2% cholesterol plus 0.15% murideoxycholic acid. Animals in groups 2 to 4 were killed after an additional 6 wk; animals in groups 5 to 7 were killed after an additional 12 wk. Gallstone dissolution did not occur in any group. The gallstones in groups 2, 3, 5 and 6 were typical cholesterol aggregates, as determined by polarized light microscopy and Fourier transform infrared spectrometry. The gallstones of the murideoxycholic acid group were large, solitary, dark stones that appeared radiopaque under 22 kVp x-ray examination. Scanning electron microscopy showed that in these stones the cholesterol crystals had been replaced by an amorphous material, both within the stone and on the stone surface. Chemical analysis indicated that at the end of 12 wk the calcium/sodium salt of the taurine conjugate of murideoxycholic acid (murideoxycholyl taurine) comprised 70% of the stones; protein, cholesterol and small amounts of other bile salts were also present. In vitro studies confirmed the insolubility of the sodium and calcium salts of murideoxycholyl taurine. These studies indicate that the hydrophilic bile acids, murideoxycholic acid and ursodeoxycholic acid, did not achieve gallstone dissolution under the conditions used. In the animals fed murideoxycholic acid, an insoluble calcium salt of murideoxycholyl taurine replaced cholesterol as the major constituent of gallbladder stones. This is the first example of an insoluble dihydroxy taurine-conjugated bile acid; administration of the unconjugated bile acid induced precipitation of a kind of gallstone not previously reported. The final result was transformation of cholesterol stones to bile salt stones. 相似文献
89.
血管紧张素Ⅱ受体—1在清醒大鼠血压波动性调节中的作用 总被引:6,自引:0,他引:6
目的:探讨血管紧张素Ⅱ受体-1(AT1受体)在清醒WKY大鼠和自发性高血压大鼠(SHR)血压波动性(BPV)调节的作用。方法:应用计算机化清醒自由活动大鼠血流动力学监测技术,分别观察了:(1)静注新型非肽类AT1受体拮抗剂Losartan(Los);92)静注神经节阻断剂氯异朵铵;(3)静注Chlor和Los;(4)静滴血管紧张素Ⅱ(ANGⅡ)及静注Chlor后静滴ANGⅡ对WKY大鼠和SHR血压 相似文献
90.
30例肝硬化食管静脉曲张破裂大出血患者,用垂体后叶素0.2~0.4U/min连续静脉滴注和硝酸甘油含服联合治疗。结果表明,近期止血有效申达80%,死亡率10%;无一例出现严重心绞痛和心电图异常。 相似文献