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991.
Intracellular mechanisms of halothane's effect on isolated aortic strips of the rabbit 总被引:17,自引:0,他引:17
The intracellular mechanisms of halothane action were examined in vascular smooth muscle from the aorta. Medial layers of the aorta from rabbits were mounted on photodiode tension transducers, stretched to 20 mg resting tension, and "skinned" with saponin. The skinned fiber preparations were then immersed in bathing solutions to study the effects of halothane (0.5-2%) on Ca2+ activation of the contractile proteins, and Ca2+ uptake and release from the sarcoplasmic reticulum (SR) using caffeine-induced tension transients. For comparison, isolated intact aortic rings were mounted on Blinks' dual tissue bath and attached to force transducers. The preparations were contracted with either 40 mM KCl, or norepinephrine (NE) followed by acetylcholine (ACh)- or sodium nitroprusside (SNP)-induced relaxation. At steady state contraction or relaxation, the effects of halothane (1-3%) were studied. The steady state tension during halothane was expressed as a percentage of the steady state tension before administration of halothane. In the isolated intact aortic rings, halothane (1-3%) produced biphasic effects on KCl-induced tension, i.e., an initially slight increase followed by decreases, independent of endothelium. Halothane markedly increased tension in the ACh- or SNP-relaxed state. The effects were dose-dependent. In the skinned aortic strips, halothane slightly decreased maximum Ca2+-activated tension development of the contractile proteins. Halothane decreased Ca2+ accumulation in the SR and increased Ca2+ release from the SR in a dose-dependent manner. The halothane-induced increases in Ca2+ release from the SR were blocked by ryanodine, an SR Ca2+ release channel blocker. It is concluded that halothane directly causes vascular contraction or relaxation, depending on the condition, and that halothane's effects on the SR may play a role. 相似文献
992.
D N Zhang 《中医杂志(英文版)》1989,9(3):159-162
The "Serial Recipes for Renal Failure" (SRRF), are 11 recipes formulated in accordance with the morbid mechanisms of deficiency, stagnation, dampness and reverse in chronic renal failure (CRF), for the purposes of replenishing deficiency, and activating blood stagnation as an etiological approach and eliminating dampness and suppressing reverse flow as an symptomatic approach. In the treatment of 64 cases of CRF, the total effective rate of SRRF was 84.4%, and the markedly effective rate 51.6%. The author holds that blood stagnation is the main point in the pathogenic mechanism and recommends comprehensive therapeutic measures. 相似文献
993.
Ischemic heart disease (IHD) is correlated with the Immunodisturbances. In this study, the immunological effects of Kuo Guan No 1, a powder for aiding Qi and activating the blood, in 17 cases of Qi Yang Xu Xue Yu (QYXXY, ) syndrome, Kuo Guan No 2, powder for nourishing the Yin and activating the blood, in 14 cases of Yin-Xu Xue-Yu (YXXY, ) syndrome had been observed in one month treatment. After treatment with both powder of Kuo Guan No 1 and Kuo Guan No 2, the increased levels of IgG, CIC, IC-IgG and IC-C3 in serum and the numbers of B cells in peripheral blood lymphocyte (PBL) of the patients with Ben-Xu Biao-Shi (BXBS, ) syndrome of IHD angina were markedly decreased and showed no significant difference while compared with the normal controls (P greater than 0.05); the numbers of OKT+3, OKT+4 and OKT+8 cells in PBL, which were lower before treatment in both groups, were obviously increased and showed no marked difference with the controls (P greater than 0.05); the higher ratio of T4/T8 was lowered in group of YXXY syndrome, and showed no difference while compared with the controls (P greater than 0.05), but the ratio in QYXXY syndrome group was lowered than that in the controls (P less than 0.05). After the treatment with Kuo Guan No 1, the increased level of C3 in serum in QYXXY group was lowered down to that of the controls (P greater than 0.05). The results indicated that it is reasonable to consider that "Kuo Guan" powder is an immunoregulative preparation for patients with BXBS syndrome of IHD angina. 相似文献
994.
A clinical study was carried out in 31 patients (39 limbs) with thromboangiitis obliterans (TAO, Buerger's Disease) by Chinese herbs "Vascular No.3". Doppler ultrasound flow velocity tracing at the femoral, popliteal, posterior tibial and dorsalis pedis levels and blood pressure at the ankle level were measured. The results showed that TAO patients treated with "Vascular No.3" had a total effective rate of 92.3% and a distinct improvement of 76.9%. The results of Doppler ultrasound proved that "Vascular No.3" significantly decreased arterial lumen stenosis level, increased blood velocity and local flow, promoted developing arterial collaterals and improved vaso-functional conditions. 相似文献
995.
呼出气氢测定试验对飞行人员乳糖酶缺乏症的研究 总被引:1,自引:1,他引:0
对66名汉族飞行人员进行乳糖呼出气氢测定试验,乳糖吸收不良的发生率为83.3%,其中乳糖不耐受者占34.6%;与一般汉族人群无明显差别。对10名确定为中度以上乳糖吸收不良的飞行人员进行250ml鲜牛奶的试验结果,有50%呼出气氢含量在正常范围,并无一例出现胃肠道症状。提示较长期食用牛奶未能使乳糖酶缺乏状态发生改变,但每日食用适量牛奶属合理营养。 相似文献
996.
997.
Antonio C. Buzaid David S. Alberts Janine Eispahr Kurt Mosley Yei-Mei Peng Kendra Tutsch Collin P. Spears Harinder S. Garewal 《Cancer chemotherapy and pharmacology》1989,25(2):124-130
Summary Dipyridamole (DP) has previously been studied both in vitro and in vivo in combination with various antimetabolites, including methotrexate and 5-fluorouracil (5FU). We evaluated in vitro and clinically the effects of adding DP to fluorodeoxyuridine (FUDR) in colorectal cancer. Using a human colony-forming assay, we observed that 0.05 M DP increased the cytotoxicity of FUDR by a median of 33.5-fold vs 1.5-fold for 5FU against human colon-cancer cell lines. The mechanism of the DP-enhanced antitumor activity of FUDR is not completely understood but appears to be related to a profound inhibition by DP of thymidine accumulation in and FUDR efflux from colon-cancer cell lines. On the basis of these in vitro results, 28 patients with metastatic colon cancer were entered in a clinical trial of monthly courses of 0.1 mg/kg FUDR daily for 14 days and 75 mg oral DP 5 times daily for 14 days starting on the 3rd day of continuous i.v. FUDR infusion. The pharmacokinetics of DP was studied in three patients; the results showed that 98% of total serum DP was protein-bound and that free DP levels were significantly lower than the concentrations necessary for the expected in vitro DP/FUDR modulation. Treatment was well tolerated, with only 12 patients developing mild to moderate toxicity. Of 27 evaluable patients, 4 achieved a partial response that lasted 2, 3, 5, and 6+ months. This relatively low response rate (15%), which is similar to that achieved with FUDR alone, may be explained by the low steady-state plasma concentrations of free DP achieved in our patients. Other means of DP administration, such as i.v., i.a., and i.p. injection, may be required to achieve free DP concentrations necessary for successful biochemical modulation of FUDR in patients.Supported in part by grants CA17094, CA23074, and CA39629 from the National Institutes of Health, Bethesda, Md 20205, and a grant from the Arizona Chronic Disease Commission. HSG is a recipient of an American Cancer Society Career Development Award 相似文献
998.
Toyofuku T Yoshida J Sugimoto T Zhang H Kumanogoh A Hori M Kikutani H 《Nature neuroscience》2005,8(12):1712-1719
Sema3A, a prototypical semaphorin, acts as a chemorepellent or a chemoattractant for axons by activating a receptor complex comprising neuropilin-1 as the ligand-binding subunit and plexin-A1 as the signal-transducing subunit. How the signals downstream of plexin-A1 are triggered upon Sema3A stimulation, however, is unknown. Here we show that, in the presence of neuropilin-1, the FERM domain-containing guanine nucleotide exchange factor (GEF) FARP2 associates directly with plexin-A1. Sema3A binding to neuropilin-1 induces the dissociation of FARP2 from plexin-A1, resulting in activation of FARP2's Rac GEF activity, Rnd1 recruitment to plexin-A1, and downregulation of R-Ras. Simultaneously, the FERM domain of FARP2 sequesters phosphatidylinositol phosphate kinase type I isoform PIPKIgamma661 from talin, thereby inhibiting its kinase activity. These activities are required for Sema3A-mediated repulsion of outgrowing axons and suppression of neuronal adhesion. We therefore conclude that FARP2 is a key molecule involved in the response of neuronal growth cones to class-3 semaphorins. 相似文献
999.
1000.
新生期大白鼠皮下注射谷氨酸单钠对成年后下丘脑α-促黑素细胞激素神经元免疫反应性的影响 总被引:2,自引:0,他引:2
本文用免疫组化方法研究了新生期大白鼠注射谷氨酸单钠(MSG)对成年后下丘脑α-促黑素细胞激素(α-MSH)免疫反应神经元的影响,结果显示MSG处理以后下丘脑弓状核区α-MSII免疫反应神经元减少甚至完全消失,但不影响下丘脑背外侧区的α-MSH神经元群。文中还讨论了这两群α-MSH神经元的生理作用。 相似文献