共查询到20条相似文献,搜索用时 140 毫秒
1.
目的:探讨L-精氨酸对肾性高血压心肌肥厚大鼠左室肌原癌基因c-fos表达及血浆NO含量的影响。方法:采用免疫组织化学方法测定左室肌原癌基因c-fos蛋白表达,用比色法测定血浆一氧化氮含量。结果:通过8周治疗后,L-Arg使高血压心肌原癌基因c-fos蛋白表达,用比色法测定血浆一氧化氮含量。结果:通过8周治疗后,L-A使高血压心肌肥厚大鼠c-fos蛋白表达显著减少(P〈0.005),使血浆中NO含量 相似文献
2.
3.
高血压左心室肥厚与心肌原癌基因c-fos的表达 总被引:9,自引:0,他引:9
目的研究细胞核内原癌基因c-fos在高血压左室肥厚(LVH)发生、发展过程中的作用。方法采用两种高血压模型即自发性高血压大鼠(SHR)和两肾一夹型(2K1C)肾血管性高血压大鼠,观察在高血压所致LVH的不同阶段,收缩压(SBP)、左室重/体重比(LVW/BW)及左心室c-fos基因表达水平的变化。结果SHR在8~10周龄时已有明显的高血压和LVH,其SBP与LVW/BW均显著高于对照的WKY大鼠,左心室c-fos基因表达水平与WKY大鼠相比,差异无显著性,但二者均较高。20~22周龄与40~42周龄时,SHR的SBP、LVW/BW及左室c-fos基因表达水平明显高于对照组WKY大鼠。2K1C大鼠左肾动脉缩窄1周后就有明显的LVH,其LVW/BW较假手术组大鼠显著升高(2.90±0.13vs2.57±0.15,P<0.05),同时伴左室c-fos基因的高表达,至术后3周、10周仍保持较高水平。钙拮抗剂尼群地平和血管紧张素AT1受体拮抗剂losartan治疗10周后均可使2K1C大鼠左室c-fos基因表达水平降低。结论心肌原癌基因c-fos的高表达可能参与高血压LVH的发生、发展过程。 相似文献
4.
胰岛素抵抗高血压大鼠血小板L—精氨酸/一氧化氮系统的改变 总被引:8,自引:0,他引:8
目的 观察胰岛素抵抗高血压大鼠血小板L-精氨酸/一氧化氮系统的改变。方法 自发性高血压大鼠(SHR)自第5周至第10周喂信果糖,制备胰岛素抵抗高血压大鼠(IR)模型。在此模型上,检测血小板一氧化氮合酶(NOS)活性、一氧化氮(NO)产生量及L-精氨酸(L-Arg)转运特征,同时观察了血浆L-Arg水平、心纳素(NAP)、NO水平及cGMP水平。结果 SHR大鼠收缩压(SBP)(P〈0.01),血浆 相似文献
5.
高血压病人血小板L—精氨酸/一氧化氮系统的改变 总被引:14,自引:0,他引:14
目的原发性高血压(EH)病人(23例)与健康成年人(14)例作对照,观察高血压时血小板(Pt)左旋精氨酸(L-Arg)-一氧化氮(NO)系统的改变及L-Arg转运的特征。方法微盘测定法测定血小板孵育液中亚硝酸盐(NO2-)的含量来反映NO产生量、ADP刺激下NO的产生量;采用张新波等建立的一氧化氮合酶(NOS)测定改良法测定血小板NOS活性;放射性同位素标记测定血小板3H-L-Arg转运的动力学特征。结果EH患者Pt的NO产生量及NOS活性较对照组明显降低(P<0.01),用ADP刺激后,EH患者Pt的NO增加量仅为正常对照组增加量的60%,其L-Arg转运能力亦显著低于正常人(各浓度点P均<0.01)。最大转运速率(Vmax)仅为正常人的79%(P<0.01),而米氏常数(Km)则无明显改变(P>0.05)。结论高血压时Pt的L-Arg-NO系统存在明显异常,提示对EH患者,在降压的同时,联合应用改善L-Arg-NO系统的药物,对预防和治疗高血压减少并发症可能会有更好的效果。 相似文献
6.
左旋精氨酸对家兔心肌缺血再灌注损伤的保护作用 总被引:1,自引:0,他引:1
目的探讨左旋精氨酸(L-Arg)对心肌缺血再灌注损伤(MIRI)的保护作用。方法制备家兔MIRI模型,观察L-Arg对血清中和心肌组织中一氧化氮代谢产物(NOP)含量、乳酸脱氢酶(LDH)活性及心肌细胞形态学变化的影响。结果L-Arg保护组和非保护组比较,血清及心肌NOP明显升高(P<0.05);心肌LDH显著增高(P<0.05),而血清LDH无明显变化;心肌细胞形态学异常改变明显减轻。结论L-Arg通过提高机体一氧化氮水平而保护缺血再灌注损伤的心肌。 相似文献
7.
同型半胱氨酸对正常人血小板L-精氨酸/一氧化氮途径的影响 总被引:20,自引:0,他引:20
目的通过观察同型半胱氨酸(Hcy)对血小板L精氨酸(LArg)/一氧化氮(NO)系统的影响,探讨Hcy对血小板损伤的机制。方法健康成人6例,平均年龄(33±7)岁。晨取静脉血,将每例血样分为对照组及加Hcy组,分别测定血小板LArg转运功能;同时将上述两组分别设立加乙酰胆碱(Ach)与不加Ach组,测定血小板NO合酶(NOS)活性、NO生成量和cGMP含量。结果(1)在不同浓度的L-Arg时,Hcy组LArg转运速率均低于对照组(P<001)。(2)在Ach刺激下,NOS活性明显提高,但Hcy组提高的程度明显低于对照组(P<001)。(3)在Ach刺激下,NO生成及cGMP含量明显提高(P<001),但Hcy组仍明显低于对照组(P<005)。结论Hcy影响血小板功能可能与LArg/NO系统改变有关。 相似文献
8.
近年来人们发现原癌基因不仅与癌症的发生有关,而且在心血管系统的发病机制中也有作用,癌基因的异常表达可能是心肌肥厚、高血压和动脉粥样硬化的发病因素。本文主要阐述了原癌基因c-fos的分子生物学,c-fos表达产物的功能及其表达的调控,心血管系统调节肽对c-fos表达的调节以及c-fos与心血管系统疾病的关系。 相似文献
9.
近年来人们发现原癌基因不仅与癌症的发生有关,而且在心血管系统的发病机制中也有作用,癌基因的异常表达可能是心肌肥厚、高血压和动脉粥样硬化的发病因素。本文主要阐述了原癌基因C-fos的分子生物学,c-fos表达产物的功能及其表达的调控,心血管系统调节肽对c-fos表达的调节以及c-fos与心血管系统疾病的关系 相似文献
10.
抑制NO合酶上调大鼠血管α1—肾上腺素受体和三磷酸肌醇受体 总被引:1,自引:0,他引:1
探讨NO系统和血管α1-肾上腺素受体α1-AR)及三磷酸肌醇受体(IP3R)系统在高血压发病中的相互作用。方法在常规饲食中加入L-NAME喂饲大鼠1或4周制备大鼠高血压模型;应用放射性配基结合实验观察α1-AR及IP3R的变化。结果应用L-NAME处理一周,大鼠动脉血压升高30(2mmHg(P<0.05),血浆NOx含量则下降25%(P<0.05)。主动脉肌膜α1-AR及肌浆网IP3R密度分别增加12%和40%。L-NAME处理4周,大鼠血压升高75±8mmHg(P<0.01),血浆NOx含量下降50%(P<0.01),主动脉肌膜α1-AR及肌浆网IP3R密度分别较对照组高73%和137%(P<0.01),此时尾动脉肌膜AR及肌浆网IP3R密度亦较对照组增加55%和56%(P<0.01)。结论提示长期抑制NOS引起大鼠持续性高血压的同时,可致大鼠血管α1-AR及IP3R明显上调。 相似文献
11.
Distribution of gasses to the cast volume and volume of pores can be maintained within the acceptable limits by means of correct setting of technological parameters of casting and by selection of suitable structure and gating system arrangement. The main idea of this paper solves the issue of suitability of die casting adjustment—i.e., change of technological parameters or change of structural solution of the gating system—with regards to inner soundness of casts produced in die casting process. Parameters which were compared included height of a gate and velocity of a piston. The melt velocity in the gate was used as a correlating factor between the gate height and piston velocity. The evaluated parameter was gas entrapment in the cast at the end of the filling phase of die casting cycle and at the same time percentage of porosity in the samples taken from the main runner. On the basis of the performed experiments it was proved that the change of technological parameters, particularly of pressing velocity of the piston, directly influences distribution of gasses to the cast volume. 相似文献
12.
13.
目的本文旨在了解医务人员现代结控知识掌握的现状及培训效果?方法于培训前后进行问卷调查,内容包括:病例发现?结核病诊断及化疗?结果培训前疫情报告和转诊,回答正确者占75.2%?71.7%;对临床表现?查痰和诊断依据,回答正确者占83.5%?42.5%?40.8%;抗痨药物?用药方法?化疗原则?短化方案?短化疗程?治愈标准六项,回答正确者占58%?14.4%?20.8%?9.2%?17%?24.3%?培训后再次调查发现,90%以上医务人员对现代结控基本知识已掌握?结论各级医务人员现代结控知识是很贫乏的,因此,对其进行系统培训是极为必要的,此项工作省时?省力?投入少,可收到事半功倍的效果。 相似文献
14.
15.
John W. Braasch 《Journal of hepato-biliary-pancreatic sciences》1994,1(4):342-348
The historical evolution of the pylorus-preservation resection of the head of the pancreas is traced from the first resections early in this century to relative standardization of the operation, to a lowering of the operative mortality, and to an interest in improving nutritional status after resection. There are many theoretical advantages for the function of the upper gastrointestinal tract after pylorus and gastric preservation, such as maintenance of gastric capacitance and equilibration of osmotic pressure in gastric digestants, foodstuff digestion and absorption, and bowel motility. After the pylorus-preserving resection, gastric emptying is normal, pyloric function to prevent duodenal reflux is often normal, and gastric acids and serum levels of duodenal hormones are at normal levels, whereas after standard pancreatoduodenectomy, all of these are often abnormal. No prospective blinded studies have been published comparing nutritional values after the two operative procedures, but evidence is presented of a satisfactory result with regard to gastric capacitance, body weight gain, and lack of postgastrectomy symptoms. An undoubted advantage of the pylorus-preserving feature is a simplification of the operation. These gains are achieved without increase in operative mortality, without increase in the incidence of jejunal ulcer, and without theoretical or actual decrease in value of the procedure as a cancer operation, except in patients with duodenal carcinoma proximal to the ampulla of Vater. 相似文献
16.
17.
18.
Pylorus preservation has been advocated to decrease the morbidity associated with the classical or standard pancreaticoduodenectomy. The proposed advantages are decreased incidence of peptic ulceration, dumping syndrome, and nutritional problems. However, after an initial period of enthusiasm for the procedure, it is now being found that marginal ulceration at the duodenojejunal anastomosis is encountered with increasing frequency. Delay in gastric emptying occurs frequently, with an overall incidence of 30%. With the availability of better pancreatic enzyme supplements, the current incidence of nutritional problems and weight loss after the standard Whipple procedure is unknown. Whether there is a difference in long-term survival after the two procedures performed for adenocarcinoma of the head of the pancreas is still debatable. A controlled trial is needed to answer many of these questions, and pylorus-preserving pancreaticoduodenectomy should be used cautiously until further data become available. 相似文献
19.