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81.
为了探索单疱病毒性角膜炎的发病机制和快速诊断HSK。方法应用多聚酶链反应对感染的HSK的20只纯新西兰白兔和60例HSK患者的角膜进行了单疱病毒-1-DNA检测。结果急性感染期的5只兔角膜和12只人角膜均阳性;用稳定期45d的兔角供体行部分穿透性角膜移植术,术后50d10只兔角膜中7只阳性,稳定期6个月-6年的18只人角膜片,12只阳性;30例临床可疑HSK角膜刮取物,26例阳性;5只未感染HSK  相似文献   
82.
Injection of TFP (a specific antagonist of CaM) into the lateral ventricles of the rat brain on the fourth day of pregnancy causes marked antifertility effect in 83% of the rats (0% in the control group). Examination with the pontamone blue reaction for the implantation elucidated that the antifertitity effect was due to the blockage of implantation of the follicle. Injection of TFP into the lateral ventricles of the brain markedly reduced the concentration of CaM in hypothalamus, ovary and uterus. Serum progesterone was also reduced. However, injection glven on day 7 was ineffective to terminate the pregnancy. Injection given on certain time of pregnancy was able to reduce the cellular CaM content and to cause antifertitity. This finding demonstrated that CaM played an important rote during the course of pregnancy.  相似文献   
83.
行为实验己经证明,锌过多或缺锌均可影响脑功能。锌作为体内重要的微量元素,影响多种酶的活性及蛋白质和核酸的台成。本实验通过体外分离大鼠脑海马突触体,观察不同浓度锌离子对Ca2 -Mg2 ATP酶的活性和3H-Leu掺入突触蛋白合成的影响.结果表明:1.锌离子浓度在25μmol/L时增加该酶的活性(<0.01),并促进3H-Leur掺入蛋白质的合成(<0.05)。2.锌离子在50,100,200μmol/L的较高浓度时对Co2 -M2 ATP酶的活性有显著的抑制作用(分别为:P<0.05.P<0.01,P<0.01),仅200μmol/L对3H—Leu掺入突触蛋白合成有抑制作用。本研究提示:适量的锌对突触体功能的维持是必要的,但剂量过高则起相反作用。  相似文献   
84.
In various animal models of injury to skin, mucous membranes, muscle and brain, corticotropin-releasing factor (CRF) attenuated vascular leakage in the injured tissues. Here, the effects of CRF on a rat model of pulmonary oedema were examined. Male albino rats (220-290 g) received saline or CRF s.c., 30 min before pentobarbital anaesthesia, 60 mg/kg i.p., and 1 h before 1-epinephrine bitartrate (Epi), 30 micrograms/kg i.v. Within 30 min after Epi all (n = 27) saline-pretreated rats were dead from pulmonary oedema, but animals receiving human/rat CRF at doses of 7 to 57 micrograms/kg s.c. (n = 25) were all alive. Body wt, wet and dry wt of lungs were used to calculate an oedema index. This index increased from 3.6 +/- 0.1 to 9.6 +/- 0.3 after Epi but was inhibited by 87% after CRF 28 micrograms/kg s.c. The ED50 of CRF for reducing pulmonary oedema was 3.2 (1.3-7.4) micrograms/kg s.c. Mean arterial pressure increased from 119 +/- 4 to 167 +/- 2 mmHg after Epi 10 micrograms/kg i.v., but was not different (118 +/- 3 to 169 +/- 4 mmHg) after CRF pretreatment, 6 micrograms/kg s.c., a dose which reduced lung oedema. Pharmacokinetic estimates suggest that plasma levels of CRF sufficient to attenuate lung oedema in rats approximate those seen in pregnant women at delivery, raising the possibility that endogenous CRF may protect the maternal organism during parturition.  相似文献   
85.
用9周-39周引产胎儿标本72例,取右耳廓石蜡切片,HE和Weitert弹性纤维染色,光镜观察其弹性软骨、弹性纤维、耳廓肌和结缔组织的发生。  相似文献   
86.
"工欲善其事,必先利其器",具备抢救急重危患儿的能力,是每个儿科护士在护理危重患儿中的利器之一.因此,本文针对护理人员在急诊抢救护理过程中的问题进行分析,提出解决问题的相应对策,以提升护理专业素质.  相似文献   
87.
After eliminating confounding factors, the study was made on the relationship between height, collagen metabolism, hair zinc and excessive fluoride intake. 140 schoolchildren aged 12-13 years born and reared in endemic fluorosis areas were surveyed. The results were as follows: 1. The average height of children with dental fluorosis III degree (DF III degree) was appreciably smaller than that of children without dental fluorosis. Among children with excessive fluoride intake, a negative correlation between the height and fluoride level in staple foods was seen. 2. The more the fluoride ingested, the higher the urinary THP excreted, showing that fluoride intoxication interfered with the collagen metabolism. 3. Among children with excessive fluoride intake, the height showed negative correlation with urinary THP/Cr, suggesting that the effect of fluoride on collagen metabolism indicated the mechanism of height retardation. 4. As compared to control group with the excessive fluoride intake but without dental fluorosis group, there was a significant reduction in hair zinc in group with DF III degree, suggesting that the zinc in the body decreased because of zinc metabolism disturbance by excessive fluoride intake. But among cases with excessive fluoride intake, no appreciable correlation between hair zinc and height was found. Therefore, it could not be confirmed that the effect of fluoride on zinc metabolism affected the height development.  相似文献   
88.
不同来源HSP70的氨基酸组成分析   总被引:1,自引:0,他引:1  
使用DEAE-52离子交换层析和ATP琼脂糖亲和层析方法,从人体肿瘤细胞株,大鼠肝脏和心脏、家兔和小鼠肝脏组织中纯化了主要的热应激蛋白-HSP70,用氨基酸自动分析仪分析它的氨基酸组成。  相似文献   
89.
90.
The potassium conductance increased by BRL 34915 (BRL, cromakalim) was studied in single guinea pig ventricular myocytes by using a whole cell voltage-clamp technique. In control voltage-clamp recordings, the late current-voltage relation showed a distinct inward rectification. BRL (1–100 μM) shortened the action potential and diminished or abolished inward rectification but had no effect on the slope conductance and currents flowing during hyperpolarizing clamp steps. BRL did not decrease the slow inward current but accelerated the time constant of activation and amplitude of the outward current. Cd markedly decreased (0.2 mM) or abolished (0.4–0.6 mM) the slow inward current and BRL induced a faster outward shift of late current to a greater value. Glybenclamide (10 μM), a blocker of ATP-sensitive K+ channels, had little effect of its own on action potential, membrane currents, and I-V relation. However, in the presence of BRL, glybenclamide abolished BRL effects on action potential and currents and restored inward rectification. It is concluded that the mechanism by which BRL shortens the action potential is a faster growth of an outward current due to the reduction or abolition of the inward rectification of an ATP-dependent potassium channel. The reduction in force in non-isolated tissues appears to be an indirect result of the action potential shortening and not of a decreased slow inward current.  相似文献   
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