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61.
Background: Anesthetic preconditioning (APC) with sevoflurane reduces myocardial ischemia-reperfusion injury. The authors tested whether two brief exposures to sevoflurane would lead to a better preconditioning state than would a single longer exposure and whether dual exposure to a lower (L) concentration of sevoflurane would achieve an outcome similar to that associated with a single exposure to a higher (H) concentration.

Methods: Langendorff-prepared guinea pig hearts were exposed to 0.4 mm sevoflurane once for 15 min (H1-15; n = 8) or 0.4 mm (H2-5; n = 8) or 0.2 mm sevoflurane (L2-5; n = 8) twice for 5 min, with a 5-min washout period interspersed. Sevoflurane was then washed out for 20 min before 30 min of global no-flow ischemia and 120 min of reperfusion. Control hearts (n = 8) were not subjected to APC. Left ventricular pressure was measured isovolumetrically. Ventricular infarct size was determined by tetrazolium staining and cumulative planimetry. Values are expressed as mean +/- SD.

Results: The authors found a better functional return and a lesser percentage of infarction on reperfusion in H2-5 (28 +/- 9%) than in H1-15 (36 +/- 8%; P < 0.05), L2-5 (43 +/- 6%; P < 0.05), or control hearts (52 +/- 7%; P < 0.05).  相似文献   

62.
肾病综合征血清锌,铜测定及临床意义   总被引:3,自引:0,他引:3  
本文应用原子吸收光谱法测定40例肾病综合征患儿血清锌、铜,并进行初步的探讨.材料与方法全部标本来自我院住院治疗的肾病综合征患儿共40例,男24例,女16例。年龄2岁~12岁.其中单纯性肾病32例,肾炎性肾病8例。对每一患儿均同时测定血清锌、铜和血清总蛋白、白蛋白及补体定量。血清锌、铜测仪为日本日立公司180-80型原子吸收分光光度对。试剂:1.稀释液剂为10%硝酸配成6%正丁醇液。2.标准应用液将1000ppm高纯金属锌、铜贮备液用1%稀硝酸稀释至一定浓度贮备。同时与样品同样10倍稀释.方法1.标本采集用玻璃毛细管收集耳垂血。凝…  相似文献   
63.
1 Introduction Exposure to hostile stressors causes a series of coor- dinated responses in the body, such as alterations of neu- roendocrine secretion, immune reaction and behavioral manifestation to maintain homeostasis stability and sur-vival of the organisms. Stressors are divided into two main categories: physical, or systemic, and psychological, or emotional / processive. Each stressor might activate a spe- cific central pathway to induce a special neuroendocrine response, even cause stre…  相似文献   
64.
65.
E1TorVibioCholeraeStrainSM_6andJiangsu1dStrain¥JiangXiaowan,etal.ACTAACADEMIAEMEDICINAENANJING,1994,14(2):163-164AbstractE1To?..  相似文献   
66.
上消化道出血是指食管、胃、十二指肠、空肠上端以及胰腺、胆道的急性出血,为内科常见的急重症之一,及时有效地止血是保证抢救成功的前提。近年来中医对于本病的治疗积累了较丰富的经验,从而弥补了单纯运用西药的某些不足之处。我们自拟益胃止血安治疗胃及十二指肠溃疡和炎症等  相似文献   
67.
Background: Morphine pretreatment via activation of [delta]1-opioid receptors induces cardioprotection. In this study, the authors determined whether morphine preconditioning induces ischemic tolerance in neurons.

Methods: Cerebellar brain slices from adult Sprague-Dawley rats were incubated with morphine at 0.1-10 [mu]m in the presence or absence of various antagonists for 30 min. They were then kept in morphine- and antagonist-free buffer for 30 min before they were subjected to simulated ischemia (oxygen-glucose deprivation) for 20 min. After being recovered in oxygenated artificial cerebrospinal fluid for 5 h, they were fixed for morphologic examination to determine the percentage of undamaged Purkinje cells.

Results: The survival rate of Purkinje cells was significantly higher in slices preconditioned with morphine (>= 0.3 [mu]m) before the oxygen-glucose deprivation (57 +/- 4% at 0.3 [mu]m morphine) than that of the oxygen-glucose deprivation alone (39 +/- 3%, P < 0.05). This morphine preconditioning-induced neuroprotection was abolished by naloxone, a non-type-selective opioid receptor antagonist, by naltrindole, a selective [delta]-opioid receptor antagonist, or by 7-benzylidenenaltrexone, a selective [delta]1-opioid receptor antagonist. However, the effects were not blocked by the [mu]-, [kappa]-, or [delta]2-opioid receptor antagonists, [beta]-funaltrexamine, nor-binaltorphimine, or naltriben, respectively. Morphine preconditioning-induced neuroprotection was partially blocked by the selective mitochondrial adenosine triphosphate-sensitive potassium channel antagonist, 5-hydroxydecanoate, or the mitochondrial electron transport inhibitor, myxothiazol. None of the inhibitors used in this study alone affected the simulated ischemia-induced neuronal death.  相似文献   

68.
Background: Isoflurane preconditions neurons to improve tolerance of subsequent ischemia in both intact animal models and in in vitro preparations. The mechanisms for this protection remain largely undefined. Because isoflurane increases intracellular Ca2+ concentrations and Ca2+ is involved in many processes related to preconditioning, the authors hypothesized that isoflurane preconditions neurons via Ca2+-dependent processes involving the Ca2+- binding protein calmodulin and the mitogen-activated protein kinase-ERK pathway.

Methods: The authors used a preconditioning model in which organotypic cultures of rat hippocampus were exposed to 0.5-1.5% isoflurane for a 2-h period 24 h before an ischemia-like injury of oxygen-glucose deprivation. Survival of CA1, CA3, and dentate neurons was assessed 48 later, along with interval measurements of intracellular Ca2+ concentration (fura-2 fluorescence microscopy in CA1 neurons), mitogen-activated protein kinase p42/44, and the survival associated proteins Akt and GSK-3[beta] (in situ immunostaining and Western blots).

Results: Preconditioning with 0.5-1.5% isoflurane decreased neuron death in CA1 and CA3 regions of hippocampal slice cultures after oxygen-glucose deprivation. The preconditioning period was associated with an increase in basal intracellular Ca2+ concentration of 7-15%, which involved Ca2+ release from inositol triphosphate-sensitive stores in the endoplasmic reticulum, and transient phosphorylation of mitogen-activated protein kinase p42/44 and the survival-associated proteins Akt and GSK-3[beta]. Preconditioning protection was eliminated by the mitogen-activated extracellular kinase inhibitor U0126, which prevented phosphorylation of p44 during preconditioning, and by calmidazolium, which antagonizes the effects of Ca2+-bound calmodulin.  相似文献   

69.
INTRODUCTION Parkinson抯 disease (PD), a debilitating neurodegenerative disorder, is featured with bradykinesia, resting, muscular rigidity, gait disturbances, and postural reflex impairment[1]. PD is rare before age of 50 years, but it increases dramatically with older ages, with peak onset occurring during the age of 70-85 years. In the United States, prevalence of PD in all age groups is approximately 150 per 100 000 and is roughly 30 per 100 000 at age of less than 50 years and 800 …  相似文献   
70.
郭海英 《中国药店》2005,(5):102-102,104
又到初夏季节,以消暑功能著称的藿香正气类产品也即将迎来它一年一度的销售高峰.不过,许多人并不知道,除了可以用作消暑外,藿香正气还有着非常广泛的用途:比如北京人拿它来治腹泻,广东人觉得它治胃胀效果比较好,哈尔滨人则认为喝酒时服用霍香正气正好可以用来解酒等等.  相似文献   
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