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11.
Triflavin, an Arg-Gly-Asp (RGD)-containing peptide, purified from snake venom of Trimeresurus flavoviridis, inhibits human platelet aggregation through the blockade of fibrinogen binding to fibrinogen receptors associated with glycoprotein IIb/IIIa complex. In this report, we examined the effect of triflavin on tumor cells (human hepatoma J-5)-induced platelet aggregation (TCIPA) of heparinized platelet-rich plasma (PRP). ADP-scavenger agents, apyrase (10 U/ml) and creatine phosphate (5 mM)/creatine phosphokinase (5 U/ml) did not inhibit TCIPA while hirudin (5u/ml) completely inhibited it. J-5 cells initially induced platelet aggregation, then blood coagulation occurred. J-5 cells concentration-dependently shortened the recalcification time of normal as well as Factor VIII, IX-deficient human plasmas, while it was inactive at shortening the recalcification time of Factor VII-deficient plasma, suggesting J-5 cells induced platelet aggregation through activation of extrinsic pathway, leading to thrombin formation as evidenced by the amidolytic activity on S-2238 by expressing tissue factor-like activity. Triflavin inhibited TCIPA in a dose-dependent manner (IC50, 0.02 μM). When compared on molar ratio, triflavin was approximately 30,000 times more potent than GRGDS (IC50,0.58 mM). On the other hand, GRGES showed no significant effect on TCIPA, even its concentration was raised to 4 mM. Additionally, the monoclonal antibodies, raised against glycoprotein IIb/IIIa complex (i.e., 7E3 and 10 E5) inhibited J-5 TCIPA. In conclusion, we suggest the inhibitory effect of triflavin on J-5 TCIPA may be chiefly mediated by the binding of triflavin to the fibrinogen receptor associated with glycoprotein IIb/IIIa complex on platelet surface membrane.  相似文献   
12.
Two phospholipase A2 (PLA2) enzymes, TMVPLA2 I and TMVPLA2 II, isolated from Trimeresurus mucrosquamatus venom induced rat hind-paw oedema. Recovered myeloperoxidase activity increased within 1 h and was greatly elevated in the rat paw 3-6 h after subplantar injection of these venom PLA2 enzymes. Methotrexate pretreatment significantly reduced not only the peripheral leucocyte count but also venom PLA2-induced paw oedema. In rat isolated PMN leucocyte suspension, venom PLA2 induced superoxide radical formation. Paw swelling caused by TMVPLA2 I or TMVPLA2 II was only slightly or not, respectively, reduced in the rats pretreated with anti-platelet plasma, which reduced peripheral blood platelet count by greater than 96%, suggesting platelets are not involved. In isolated platelet preparation, TMVPLA2 I induced platelet activation in a concentration-dependent manner, while TMVPLA2 II had no effect. Pretreatment with diphenhydramine/methysergide greatly suppressed the oedematous responses caused by the two venom PLA2 enzymes; the residual responses were significantly further depressed by aspirin. The oedematous responses caused by the enzymes were also suppressed by FPL 55712, BW 755C, dexamethasone, superoxide dismutase/catalase, isoprenaline and terbutaline. However, BN 52021 and L 652731, both platelet aggregating factor antagonists, were not effective on these responses. Thus, in addition to histamine and 5-hydroxytryptamine release by the mast cells in PLA2-induced paw oedema (Wang & Teng 1990), the results of this study indicate minor, but significant, roles for neutrophils and inflammatory mediators including prostaglandins, leukotrienes and superoxide radicals.  相似文献   
13.
本文阐述了1990年-1993年间沈阳口岸入境人员传染病监测工作的基本情况,在对6503名归国人员和2146名外籍人员进行传染病监测体检中,发现HIV感染者41人、隐性梅毒患者1人、开放性肺结核患者1人。  相似文献   
14.
复式脉冲低能量ESWL治疗肾结石769例报告   总被引:3,自引:0,他引:3  
目的探讨复式脉冲HB-V型低能量体外冲击波碎石机治疗肾结石的治疗效果.方法采用复式脉冲HB-ESWL-VG型低能量碎石机治疗直径<2.0 cm的各类肾结石769例,治疗工作电压3~9 kV,平均冲击次数2 300次.结果肾盏结石总粉碎率为97.4%,其中上中盏结石复打率为13.1%,术后3个月排净率为89.4%,下盏结石复打率为17.3%,排净率为81.5%;肾盂结石粉碎率为98.3%,复打率为6.1%,术后3个月排净率为93.0%.结论复式脉冲低能量ESWL治疗肾结石具有治疗成功率高、复打率低、无严重并发症、副作用少之优点.  相似文献   
15.
Z H Teng 《中华妇产科杂志》1992,27(4):233-4, 251
Here are reported 83 cases with pelvic congestion syndrome after tubal ligation. Radionuclide 113m in blood-pool scanning was found to be a valuable method in detecting this syndrome in 72 cases who were proved by operation with a correct diagnosis rate of 98.6%. The mild cases received non-operative treatment. The relationship between the modalities of tubal ligation and this syndrome was discussed and preventive measures suggested.  相似文献   
16.
目的 探讨部分肿瘤相关分子标志物免疫组织化学的表达与结直肠癌淋巴结转移的相关性.方法 应用免疫组织化学技术检测65例结直肠癌手术标本Ki-67、p53的表达情况,对照手术所见和手术标本的病理检查结果 ,研究这些肿瘤相关分子标志物与肿瘤的生物学特性如浸润和淋巴结转移等的关系.结果 65例结直肠癌手术标本Ki-67、p53免疫组织化学的表达与肿瘤肠壁浸润深度无明显相关性(P>0.05).Ki-67的表达及Ki-67标记指数的表达与淋巴结转移及Dukes分期有明显的相关性(P<0.01);p53标记指数的表达与淋巴结转移有相关性(P<0.05),与Dukes分期有明显的相关性(P<0.01).结论 作为反应细胞增殖活性的肿瘤相关分子标志物Ki-67,其免疫组织化学的表达程度可间接反映结直肠癌淋巴结转移状况,可能成为反映淋巴结转移的一个标志物.  相似文献   
17.
班氏丝虫病分布于临沂地区的13个县市,淡色库蚊为主要传播媒介,据开始防治前的1957年调查,微阳率15.03%;经60年代部分县的防治,70年代大面积的普查普治和重点病区的全民服药以及食用“海盐”防治,至1983年微阳率已降至0.16%。通过1984~1986三年的横纵向监测,微阳率处较低水平,未见回升趋势,蚊媒自然感染率已接近于0;在抽查10岁以下的15974名儿童中未有新感染,显示我区丝虫病传播已基本阻断。  相似文献   
18.
We investigated the effects of a novel platelet-activating factor (PAF) receptor antagonist, CIS-19 [cis-2-(3, 4-dimethoxyphenyl)-6-isopropoxy-7-methoxy-1-(N-methylformamido)-1, 2, 3, 4-tetrahydronaphthalene], on PAF-, histamine-, substance P- and antigen-induced bronchoconstriction and microvascular leakage, as well as PAF- and antigen-induced bronchial hyperreactivity to methacholine in urethane-anesthetized guinea-pigs. Administration of CIS-19 (0.5–5 mg/kg, i.v.) inhibited the increase in lung resistance induced by PAF (30 ng/kg, i.v.) in a dose-dependent manner, but failed to inhibit the increase induced by histamine (30 μg/kg, i.v.) or substance P (6.5 μg/kg, i.v.). CIS-19 (5 mg/kg, i.v.) did not inhibit the increase in lung resistance induced by ovalbumin (2 mg/kg, i.v.) in actively sensitized guinea-pigs. PAF (30 ng/kg, i.v.)-induced microvascular leakage, measured by the extravasation of Evans blue dye, was dose-dependently inhibited by CIS-19 (0.5–5 mg/kg, i.v.) in the trachea, main bronchi and intrapulmonary airways, but it did not affect histamine (30 μg/kg, i.v.)- or substance P (6.5 μg/kg, i.v.)-induced microvascular leakage at all airway levels. CIS-19 (2.5 and 5 mg/kg) did not affect ovalbumin (2 mg/kg, i.v.)-induced microvascular leakage in all airway levels in actively sensitized guinea-pigs. CIS-19 (2.5 and 5 mg/kg, i.v.) significantly inhibited PAF-induced enhancement of the bronchial response to methacholine, but had no effect on ovalbumin (0.05 mg/kg, i.v.)-induced bronchial hyperreactivity in actively sensitized guinea-pigs. It is concluded that CIS-19 is a potent PAF receptor antagonist which inhibits PAF- but not antigen-induced bronchoconstriction, microvascular leakage and bronchial hyperreactivity. These results suggest that PAF plays little or no role in early airway responses following antigen challenge. Received: 29 April 1996 / Accepted: 10 October 1996  相似文献   
19.
20.
DNA中鸟嘌呤加胞嘧啶克分子百分比含量(G Cmol%)值是一种间接反映两个物种核中DNA序列相似性的遗传指标之一.自从Lee和Belozersky把G Cmol%值用作细菌分类鉴定遗传指标以后,G Cmol%值在微生物分类鉴定方面已得到广泛应用。在真菌方面,国外于60年代已有报道,而国内  相似文献   
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