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991.
N. Z. Klyueva D. B. Ryzhov S. V. Kulikov S. K. Churina 《Bulletin of experimental biology and medicine》1997,124(2):751-753
Injection of a synthetic analog of parathyroid hypertensive factor to WKY rats considerably increases and prolongs pressor
response to adrenaline. Synthetic analog injected after adrenaline induces a short-term (3–4 min) and potent (to 250%) rise
of arterial pressure. Each subsequent injection of the synthetic analog induces a less pronounced in the amplitude and duration
pressor response. The α-adrenoblocker phentolamine completely abolishes the effects of the parathyroid hypertensive factor
analog.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 8, pp. 148–150, August, 1997 相似文献
992.
手术联合中药治疗激素性股骨头缺血性坏死的实验研究 总被引:5,自引:0,他引:5
目的 :初步探讨激素性股骨头缺血性坏死的发病机制 ,观察手术 +中药治疗本病的疗效。方法 :通过对新西兰大白兔联合应用马血清 +甲基强的松龙造模及手术处理 ,对正常组、模型组、手术组、手术 +中药组实验兔的血脂、血液流变学、血生化及股骨头标本切片观察 ,分析比较。结果 :手术 +中药治疗本病的疗效优于单纯保髋手术。结论 :手术 +活血化瘀补肾壮骨方法是股骨头缺血性坏死治疗的合理方法 相似文献
993.
目的探讨体外循环不同途径给予鱼精蛋白所产生的不良反应及地塞米松对这些不良反应的预防作用。方法将 6 4例患者按给药途径及是否预防性给予地塞米松分为 4组 :A1,A2 ,B1和B2 组。A组升主动脉给药 ,B组颈内静脉给药 ;A1,B1组给予地塞米松 ,A2 ,B2 组不给予地塞米松。观察各组注射鱼精蛋白后 3,10 ,2 0 ,30min平均动脉压 (meanarterialpressure ,MAP)、平均肺动脉压 (meanpulmonaryarterialpressure ,MPAP)及气道压力(airwaypressure ,AP)的变化。结果A1组各时间点数据无显著性差异 (P >0 .0 5 ) ,A2 组给予鱼精蛋白 3min后血压下降 (P <0 .0 5 ) ;B1组给予鱼精蛋白 3min后血压下降 (P <0 .0 5 ) ,气道压力升高 (P <0 .0 5 ) ,B2 组给予鱼精蛋白 3,10 ,2 0min后血压明显下降 (P <0 .0 5 ,P <0 .0 1) ,气道压力升高 (P <0 .0 5 ,P <0 .0 1)。结论从主动脉根部注射鱼精蛋白对血流动力学影响较静脉给药小 ,地塞米松对鱼精蛋白的副作用有一定的预防作用 相似文献
994.
Immunochemical techniques have been used to identify five antigenic (Ag) sites on apolipoprotein B-100 (apoB), the major protein constituent of very low density (VLDL), intermediate density (IDL), and low density lipoproteins (LDL). Each Ag site results from allelic variation at a specific locus of the apoB gene. In the present study, we assessed whether variations in the five Ag loci were associated with concentrations of plasma lipids or lipoprotein fractions measured by analytical ultracentrifugation in a group of 44 healthy men. Pair-wise analyses of the Ag markers revealed that Ag(a1/d), in association with either Ag(x/y) or Ag(t/z), is significantly related to plasma IDL-mass concentrations. In this cohort we detected no significant associations of the Ag alleles (singly or in combination) with plasma total cholesterol, triglycerides, LDL-cholesterol, HDL-cholesterol, or mass of total VLDL or LDL. These results suggest that genetic variations in the apoB molecule may predispose to variations in concentrations of IDL that could have consequences for atherosclerotic risk. 相似文献
995.
应用硫代乙酰胆碱-联硫代双硝基苯甲酸(ASCh-DTNB)比色测定法,测定了40名健康者及5名贫血者血样的全血胆碱酯酶(bl-ChE)活力值、红细胞胆碱酯酶(e-ChE)活力值及血浆胆碱酯酶(p-ChE)活力值,探讨它们之间的比例关系并用红细胞计数值(RBC)校正酶活力。结果表明:e-ChE与b1-ChE之间关系密切(r=0.948,P<0.001),e-ChE稳定地占bl-ChE的84.97%,在质和量两方面验证了以bl-ChE值表示e-ChE值的可靠性和可信程度,血液胆碱酯酶(b1ChE)活力主要取决于e-ChE活力,RBC值的离散对e-ChE值有极大影响,故用RBC值校正e-ChE活力,这样可缩小人群测定值的变异度,得到较难确的群体均值;消除男女之间测定值的差异,建立更合理和通用的临界参比值,极大地方便了使用,使血液胆碱酯酶(CHE)活力测定法在防治有机磷农药中毒中的应用,更为敏感和特异。 相似文献
996.
Summary A rapid and quantitative method for the determination of benzodiazepines using high-performance liquid chromatography (HPLC)
with diode-array detection (DAD) is reported. The drugs were extracted from serum, blood or post-mortem blood using C18 extraction columns. Brotizolam was used as internal standard. Experiments with spiked serum/blood samples resulted in recoveries
between 75% and 94% for all investigated benzodiazepines. Excellent linearity was obtained over the concentration range 5–1500
ng benzodiazepine/ml. The limit of detection was approximately 2 ng/ml. The detection of low therapeutic serum levels of highly
potent benzodiazepines is also possible.
相似文献
997.
Gerhard Adam Jrg Neuerburg Elmar Spüntrup Andreas Mühler Kira Scherer Vet Surg Rolf W. Günther 《Journal of magnetic resonance imaging : JMRI》1994,4(3):462-466
Gadolinium-DTPA (diethylenetriaminepentaacetic acid)-cascade-polymer, a potential new blood pool contrast agent for magnetic resonance (MR) imaging, was compared with a known blood pool agent, Gd-DTPA-polylysine, in an animal model. The relative signal intensities of liver, renal cortex, pancreas, and trunk muscle were assessed in 12 pigs between 4 seconds and 120 minutes after injection of a 20 μmol/kg dose of each contrast agent, by using a FLASH (fast low-angle shot) sequence. Except for muscle, all tissues showed visible enhancement after injection of either contrast agent. After injection of Gd-DTPA-polymer, enhancement patterns in the liver, renal cortex, and pancreas were similar to those seen after injection of Gd-DTPA-polylysine. No statistically significant differences in enhancement between the two contrast agents were found at any time point. The authors conclude that the contrast kinetics of Gd-DTPA-cascade-polymer are similar to those of Gd-DTPA-polylysine and that this agent may also be used as a blood pool contrast agent for MR imaging. 相似文献
998.
999.
Summary
The compartment syndrome (cs) is characterized by an increased tissue pressure in a limited space. Pathophysiologically, it
is a multifactorial disease that is potentially induced by an initial trauma and develops according to the existence of cofactors.
Cofactors are, for instance, the circulation of the patient and the initial treatment of the impending cs. In particular,
the microcirculation is altered with endothelial destruction, development of a capillary leak, protein loss from intravasal
space and the development of an interstitial and intracellular third space. An impaired drainage of the lymphatic and venous
system causes a venous infarction. An arterial infarction results if the tissue pressure exceeds the arteriolar pressure.
An accompanying ischemia reperfusion mechanism increases the trauma load. In disadvantageous cases, the patients are in danger
of developing a multi-organ deficiency syndrome (MODS) by an uncontrolled inflammatory reaction, by intravasal volume loss
and by a myonephropathic systemic reaction. Clinically, the patients suffer a disproportionate amount of pain, followed by
neurological signs. Especially in noncompliant patients, tissue pressure measurement is useful. Resuscitation of the circulation
as well as splitting of casts is important. In case of a manifest cs, dermatofasciotomy has to be performed as an emergency
operation. Even if cs is diagnosed early and fasciotomy is carried out early, the development of sequellae cannot be avoided
in every single case.
相似文献
1000.