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61.
共聚焦激光扫描显微镜(MRC600)活体观测川芎嗪和去甲基肾上腺素对休克状态下家兔大脑皮质内微循环的影响 总被引:1,自引:0,他引:1
目的 :共聚焦激光扫描显微镜活体观测川芎嗪和去甲基肾上腺素对休克状态下家兔大脑皮质内微循环的影响。方法 :在开放颅窗的家兔模型上 ,荧光素标记血浆 ,罗丹明 6G标记WBC ,用共聚焦激光扫描显微镜活体观测川芎嗪和去甲基肾上腺素对休克状态下家兔大脑皮质内微循环的影响 ,并经图像分析系统测量数据 ,用SAS软件包进行统计学分析。结果 :①川芎嗪抗休克效果优于去甲基肾上腺素 ;②去甲基肾上腺素在休克状态下对口径为 60 .15 μm的动脉血管处未引起明显的血管运动 ,而川芎嗪能引起血管运动 ,尤以大剂量川芎嗪引起强烈的血管运动 ;③川芎嗪和去甲基肾上腺素增加或保持血液缘流厚度不变 ,可能是两者抗休克机制发挥作用的途径之一 ;④川芎嗪和去甲基肾上腺素引起血管运动 ,尤以中小血管处明显。结论 :川芎嗪抗休克效果优于去甲基肾上腺素。川芎嗪和去甲基肾上腺素增加或保持血液缘流厚度不变 ,可能是两者抗休克机制发挥作用的途径之一 相似文献
62.
反复注射单抗可产生抗抗体,本文探讨了鼠型单抗Hepama-I 经不同注射途径(肝动脉iHA、门静脉iPV、外周静脉iv)、联用化疗药(5-Fu+ADM+MMC+DDP 简称FAMD)、标记上核素及加用CsA 对兔抗鼠抗体(RAMA)形成的影响及与单抗廓清的关系。结果:iHH、ipv 可减少RAMA,~(131)碘使RAMA产生时间延迟且含量减低;CsA 可部分抑制RAMA 产生;FAMD 与单抗合用可降低抗抗体含量;RAMA 可加速单抗廓清。提示:CsA 是一种理想的抑制抗抗体药物,更为实用的是以核素标记单抗,同时应用化疗药,经肝动脉注入。 相似文献
63.
G. Viala P. Buser 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1974,21(3):275-284
Summary In decerebrate rabbit preparations, a gentle pressure exerted on the dorsal skin area can completely suppress the rhythmic, locomotor-like movements or the corresponding nerve discharges which easily develop in such preparations. This inhibition can also be obtained on spinal preparation (and thus does not depend upon supraspinal levels); its maximal effect (i.e. minimal pressure threshold) is located at the lumbar level. It involves tonic receptors belonging both to the skin and to muscle and/or joints. This phenomenon probably plays a role in the so-called hypnotic akinesia which, as is well known, can easily be elicited in rabbits put in dorsal decubitus.
Notes de Remerciements. Travail réalisé avec l'aide d'une subvention du C.N.R.S. (ERA 411), de l'I.N.S.E.R.M. (Contrat 71 11 64) et de la Fondation pour la Recherche médicale française. 相似文献
64.
银杏叶制剂和丹参对急性肾衰兔肾皮质局部血流量的影响 总被引:8,自引:0,他引:8
目的探讨急性肾功能衰竭(acute renal failure,ARF)兔肾皮质局部血流量(regional renalblood flow,rRBF)与血液流变学的关系,以及银杏叶制剂(Ginkgo Bilobal Extraction,GbE)、丹参对其的影响.方法用50%的甘油10 ml/kg行兔后肢肌肉加压注射,建立ARF动物模型,观察血液流变学、rRBF的变化,并给予GbE、丹参注射液对比观察.结果 ARF组血液流变学指标明显异常,rRBF明显下降.ηb、ηb、EAI、HCT等与rRBF呈明显负相关(P均<0.05).GbE组、丹参组动物血液流变学、rRBF等指标明显改善.结论 ARF时血液流变特性恶化和肾局部微循环障碍可能是造成rRBF下降的直接原因之一.GbE、丹参对甘油所致ARF家兔的血液流变特性及肾组织缺血性损害有明显的保护作用. 相似文献
65.
目的:探讨兔急性肺血栓栓塞症(PTE)时血浆及支气管肺泡灌洗液(BALF)中TNF-α,IL-8、IL-10的水平和地塞米松(Dex)的影响。方法:采用自体血栓回输法建立兔急性PTF模型。36只兔随机分为对照组、Dex治疗组和PTE模型组。用ELISA方法检测上述细胞因子(CK)水平,术毕肺组织行病理观察。结果:栓塞后上述CK均有升高,治疗后TNF-α、IL-8均有下降,IL-10变化不明显。组织病理学可见栓塞后肺动脉内血栓形成,肺组织萎缩、出血、炎性反应明显,Dex治疗后肺组织病理改变明显减轻。结论:PTE后促炎性CK在引起肺部炎性反应和肺组织及肺动脉病损中起了重要作用,抗炎治疗可以明显减轻CK引起的这种损伤。抗炎治疗能降低PTE急性期病死率,改善远期预后,CK可能起了很重要的作用。 相似文献
66.
67.
Wolfgang Müller-Felber Klaus Küllmer Petra Fischer Carl-Detlev Reimers Stefan Wagner Ullrich Harland Martin Schmidt-Achert Dieter Pongratz 《Virchows Archiv : an international journal of pathology》1993,422(4):277-283
Leu-19 antigen, which seems to be identical with neural cell adhesion molecule (N-CAM), plays a major role in the innervation of muscle cells, and in adult muscle appears after denervation and during regeneration of muscle fibres, where it acts as part of a signalling system increasing the probability of re-innervation. This combined enzyme-histochemical and immunohistochemical study examined whether this signalling process was regulated in a uniform or differential pattern for type 1 and type 2 muscle fibres. The subscapular nerve of 18 rabbits was transsected with subsequent complete denervation of the supraspinatus muscle. Leu19 and N-CAM immunohistochemistry was performed 2 to 64 days after surgery. Whereas in normal muscle there are virtually no Leu-19/N-CAM positive muscle fibres; from day 2 after denervation an increasing proportion of fibres expressed Leu-19/N-CAM, prior to any neurogenic atrophy. In the early stage of denervation Leul9/N-CAM expression was confined to type 1 fibres. After 11 days nearly all fibres were Leul9/N-CAM positive irrespective of their fibre type. Sixty-four days after denervation type 1 fibres became Leu19/N-CAM negative, while atrophic type 2 fibres showed intensive staining. Thus, expression of Leu-19 antigenity is differently regulated in both fibre types. 相似文献
68.
Judy Y. Su 《Pflügers Archiv : European journal of physiology》1992,421(1):1-6
Ryanodine, a blocker for Ca2+-release channels of the sarcoplasmic reticulum (SR Ca2+-release channels), induces depression of myocardial contraction in isolated intact muscle, which is consistent with depression of the caffeine-induced tension transient in skinned muscle fibers. In isolated SR, ryanodine binds to a specific receptor with high affinity, and this binding is enhanced by caffeine and increasing Ca2+ and decreased by increasing Mg2+. The aim of this study was to test the hypothesis that depression of myocardial contraction is mediated by changes in ryanodine-receptor binding properties. Accordingly, factors (caffeine, Ca2+, and Mg2+) affecting ryanodine-receptor binding properties in the isolated SR membrane were studied in skinned myocardial fibers from adult rabbits. The depression of the caffeine-induced tension transient by ryanodine (ryanodine depression) influenced by these three factors was measured. In a dose-dependent manner, increasing caffeine or Ca2+ concentrations enhanced the ryanodine depression. The concentrations for 50% ryanodine depression (IC50) approximated 7mM for caffeine, and pCa 5.25 for Ca2+. When 1 M ryanodine and 25 mM caffeine were combined, ryanodine depression was independent of Ca2+ at low Ca2+ concentrations (20%–30% at pCa>8 and 7.5) and was a direct function of Ca2+ at higher concentrations (pCa 7.5–6.0 with IC50 approx. pCa 6.75). In contrast, increasing Mg2+ reduced the ryanodine depression with IC50 approximately equal to pMg 3.3. In conclusion, the caffeineor Ca2+-enhanced, and Mg2+-reduced ryanodine depression observed in this study is consistent with known ryanodinereceptor binding properties. 相似文献
69.
目的 :探讨辛伐他汀对体外培养兔血管平滑肌细胞增殖的影响及意义。方法 :16只雄性新西兰兔随机分为血清对照组和三个不同剂量的辛伐他汀亚组 (每日分别给予辛伐他汀 5mg/kg、10mg/kg、15mg/kg) ,7天后采血并混合每组 4只兔血 ,无菌分离制备三亚组的辛伐他汀含药血清。采用内皮素 1(ET 1)刺激正常喂饲原代培养兔主动脉血管平滑肌细胞的方法 ,建立血管平滑肌细胞增殖模型。采用MTT及3H TdR法检测各组辛伐他汀含药血清对血管平滑肌细胞增殖的作用。结果 :与不含药的正常对照组相比 ,不同亚组辛伐他汀含药血清呈剂量依赖性抑制血管平滑肌细胞增殖 (P <0 .0 1~0 .0 5 )。结论 :兔口服辛伐他汀后的血清具有抑制血管平滑肌细胞增殖的作用 相似文献
70.
In rabbit hearts arrested by a carnosine-buffered cardioplegic solution the incorporation of [1-14C]acetate into lipids was investigated. After 10–20 and 60 min of ischemia the radioactivities of phospholipids, mono-, di-, and triacylglycerols, acyl-CoA, acylcarnitine, and free fatty acids were determined. In the first period of ischemia mainly acylcarnitine was labelled (ca. 50%) and only 25% of [14C]-activity was found in phospholipids which showed the lowest specific activity of all lipid classes. After 60 min of ischemia the percentage of total radioactivity of acylcarnitine and phospholipids was decreased, whereas that of neutral lipids was increased to more than 50%. During the increase of total radioactivity the relative specific activity of all lipids decreased except that of triacylglycerols. Only fatty acids up to chain lengths of 16 carbon atoms were labelled. Lauric and myristic acid had high specific activities. These results indicated de novo synthesis of fatty acids accumulating in triacylglycerols during ischemia of the arrested heart. 相似文献