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31.
心肌钠钙交换在调节心肌细胞内外钠、钙平衡中发挥重要作用。钠钙交换分为前向型和逆向型2种。在心力衰竭、心肌缺血、心肌再灌注等病理情况下,通过钠钙交换器的离子交换可产生致心律失常性的一过性内向电子流,引起延迟后除极和非折返激动型的室性心动过速。钠钙交换器抑制药在预防这些病理情况下的心律失常具有潜在的作用。  相似文献   
32.
Overactive bladder (OAB) is a prevalent and costly condition that can affect any age group. Typical symptoms include urinary urgency, frequency, incontinence and nocturia. OAB occurs as a result of abnormal contractions of the bladder detrusor muscle caused by the stimulation of certain muscarinic receptors. Therefore, antimuscarinic agents have long been considered the mainstay of pharmacologic treatment for OAB. Currently, there are five such agents approved for the management of OAB in the United States: oxybutynin, tolterodine, trospium, solifenacin and darifenacin. This article summarizes the efficacy, contraindications, precautions, dosing and common side effects of these agents. All available clinical trials on trospium, solifenacin and darifenacin were reviewed to determine its place in therapy.  相似文献   
33.
Summary The objective of this study was to evaluate the effect of two non-steroid anti-inflammatory drugs, indomethacin and metamizole, on ureteral peristalsis during acute occlusion similar to the situation in renal colic. In 12 pentobarbital anesthetized sheep, both ureters were cannulated and the frequency of ureteral contractions, urine flow, mean ureteral pressure and blood pressure were recorded during 10-min control and i.v. drug administration periods. Both indomethacin (1–2 mg/kg) and metamizole (60–120 mg/kg) showed a dose dependent reduction in peristaltic frequency without reduction of the mean pressure. In addition, the pressure amplitude of the peristaltic waves was also lowered, particularly with indomethacin. Only indomethacin reduced the urine flow. Arterial blood pressure was elevated by both drugs, particularly after the first dose of indomethacin. It can be concluded that indomethacin and metamizole reduce ureteral peristaltic frequency, probably blocking the impulse transmission at the ureteropelvic junction.For the partial fulfillment of a Master's degree in Pharmacology  相似文献   
34.
氟西汀与阿米替林治疗105例抑郁障碍病人的双盲对照试验   总被引:6,自引:4,他引:2  
目的:评价国产氟西汀的抗抑郁作用及安全性。方法:采用随机、双盲对照、多中心研究,分为国产氟西汀组57例(男性22例,女性35例;年龄40±s13a),口服氟西汀20mg,qd,阿米替林57例(男性27例,女性30例;年龄40±14a),口服阿米替林75mg,bid,疗程6wk。结果:氟西汀治疗抑郁障碍的疗效与阿米替林相当,总有效率分别为85%及92%(P>0.05);氟西汀组的主要副作用有口干、便秘、恶心、心动过速等,但较之阿米替林程度轻且发生率低。结论:氟西汀的抗抑郁作用与阿米替林相当,副作用少,服用方便。  相似文献   
35.
人癌干细胞集落形成测定常用双层琼脂平皿法。新法系采用园形玻璃毛细管法培养!可 以减少细胞用量及药物消耗。管内径为1.3mm,管长9.75cm,内盛15.000有核细胞/50μl,培养7~ 14天。50例肿瘤活检标本生长成功率为88%,并可供化疗药物敏感性试验用。这种微量化检测具有 独特的优点,便于推广应用。  相似文献   
36.
In rabbit platelet rich plasma (PRP), 5-hydroxytraptamine (5-HT,0.03~3μmol/L) induced decrease in light transmission (DLT) dose-de pendently with centralization, as revealed by electron microscopy. However, 5-HT did not induced platelet aggregation and release reaction. 5-HT-induced DLT was inhibited by methysergide (0.3~30μmol/L), indomethacin (0.3~10μmol/L) and PGE_1 (0.01~0.3μmol/L) in a dose-dependent manner, but not EGTA(0.3~3mmol/L). Collagen(Coll), arachidonic acid (AA), adenosine diphosphate (ADP) and a stable thromboxane A2 analoge(STA_2) also induced DLT before aggregation by themselves, which was also inhibited by PGE_1, but not inhibited by EGTA except for Coll However,Coll-, AA-, STA_2-and ADP-induced DLT were reduced by pretreatment of PRP with 5-HT dose-depen-dently. The duration of DLT by Coll and AA were decreased from 151.4±5.93 sec and 15(?)38±0.60sec to 45.44±4.04 sec and 9.00±1.25 sec respectively ((?)±s(?) P<0.01), but not by ADP and STA_2, 3μmol/L of ADP-and 0.3μmol/L of STA_2-induced aggregation which was not accompanied with release reaction were enhanced by 5-HT pretreatment, but in those (Coil 5μg/ml, AA 100~200μmol/L and STA_2 1~3 μmol/L) with release reaction, the amount of adenosine triphosphate(ATP)were suppressed significantly (P<0.001) by 5-HT pretreatment without the effect on the magnitude of aggregation, The mobilization of cytosolic free calcium concentration ([Ca~(2+)]i) was observed after 5-HT treatment in single washed platelet, the results indicated that the basic level of [Ca~(2+)] i was 64.78±3.24nmol/L and this level was increased dose-dependently and significantly at 30 sec after administration of 5-HT and the time of peak value of [Ca~(2+)] i was at 90~100 sec.The similar time courses of suppression of ATP released during aggregation, in cases of Coll(5μg/ml), AA (200μmol/L) and STA_2(3μmol/L), by 5-HT were also found in the present experiment.  相似文献   
37.
采用综合治疗,抗炎,散瞳,局部治疗与全身应用免疫抑制疗法,治疗319例352眼外伤获得了满意的疗效,眼球挫伤104例,眼球穿孔伤93例,化学烧伤71例,眼炸伤46例。眼热烧伤5例,治疗包括及时清创胶粘或缝合,清除前房出血合理用皮质类固醇和免疫抑制剂等。眼球挫伤治愈率97.12%,穿透伤93.18%,热烧伤66.67%。319例眼外伤治愈率94.67%好转5.33%,并对各种治疗方法进行了讨论。  相似文献   
38.
应用足叶乙甙与阿糖胞苷联合化疗方案治疗13例急性单核细胞白血病取得较好疗效,13例中完全缓解8例(61.5%),部分缓解3例(23.1%),总有效率达84.6%。文中对用药剂量及疗效进行了讨论。  相似文献   
39.
In vascular smooth muscle, openers of ATP-dependent potassium channels (K ATP channels), such as P1075 (N-cyano-N’-(1,1-dimethylpropyl)-N’’-3-pyridylguanidine), produce relaxation. In this study we have investigated the effects of thiol-modifying agents on the binding of P1075 and on the 86Rb+ efflux stimulating and vasorelaxant effects of the opener in rat aortic rings. The increase in 86Rb+ efflux induced by P1075 was taken as a qualitative measure of K+ channel opening. The hydrophilic SH-group-oxidizing substance, thimerosal (1 to 100μM), abolished specific binding of [3H]-P1075 with an IC50 value of 7.6±1.2μM; at 30μM, the half time for inhibition was 38min. Two other thiol-oxidizing agents, PMB (4-hydroxy-mercuribenzoic acid) and DTBNP (2,2’-dithio-bis(5-nitropyridine)), inhibited binding up to 86% and 44%, respectively. The disulphide bond reducing substance, DTT (1,4-dithiothreitol, 0.1 to 1mM), reduced [3H]-P1075 binding by up to 20% and partially reversed the inhibitory effect of thimerosal. In 86Rb+ efflux experiments, thimerosal (3 to 100μM) concentration-dependently increased basal efflux but inhibited P1075-stimulated tracer efflux with an IC50 value of 7±1μM. The inhibitory effect occurred with a half-time of approximately 8min and was essentially reversed by DTT. In rings precontracted with noradrenaline, thimerosal inhibited the vasorelaxant effect in a noncompetitive manner, shifting the concentration-relaxation curves to the right and reducing maximum relaxation.The data show that oxidation of thiol groups interferes with the binding of the K ATP channel opener, P1075; concomitantly, the 86Rb+ efflux stimulating and the vasorelaxant effects are inhibited. Reduction of disulphide bonds by DTT has only minor effects on the action of P1075. Collectively, the results suggest that intact thiol groups are essential for the functioning of the KATP channel in rat aorta. The different kinetics governing the inhibition of opener binding and of opener-stimulated 86Rb+ efflux suggest that the SH-groups involved in the two processes differ in their accessibility to thimerosal and/or in their reactivity. Received: 7 April / Accepted: 9 July 1997  相似文献   
40.
用带血管的胎儿甲状旁腺移植术治疗甲状旁腺机能低下症,共行手术6次(腹腔内移植5次,股三角区移植1次),6次中有3例术后发生4次排斥反应。经1年8月至3.5年随防,疗效显著者2例,有效2例,失败1例。本文讨论了有关甲状旁腺移植的手术方法、注意事项、免疫抑制剂应用等问题。  相似文献   
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