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21.
The edema-producing activity of NNAVPLA2, an acidic phospholipase A2 (PLA2) enzyme from Naja naja atra venom (NNAV), was less potent than that of TMVPLA2 II, a basic PLA; from Trimeresurus mucrosquamatus venom (TMV). These edema-forming effects were greatly suppressed by pretreatment of rats with diphenhydramine/ methysergide or compound 48/80, which reduced the tissue content of histamine and serotonin. Heparin abolished and suppressed the paw edema caused by protamine and TMVPLA2 II, respectively, but had no effect on the NNAVPLA2-induced response. In isolated rat peritoneal mast cells, both PLA2 concentration dependently induced the release of histamine and β-glueuronidase. Again, TMVPLA2 II was more potent than NNAVPLA2. This degranulation effect of mast cells caused by TMVPLA2 II and protamine was inhibited by heparin, while that caused by NNAVPLA2 was unaffected. The edema-forming and mast cell degranulation effects were greatly decreased in both PBPB-modified NNAVPLA2 and PBPB-modified TMVPLA2 II, in which the catalytic activity of the enzymes was completely lost. PBPB-modified TMVPLA2 II-induced paw edema was also suppressed by heparin. Furthermore, this edematous response was totally reversed in rat pretreated with aspirin in combination with diphenhydramine and methysergide. These results suggest that the edema-forming effect of PLA2 is probably dependent on the presence of catalytic, positive charge and pharmacological sites on its molecule.  相似文献   
22.
本文从护理诊断的概念与发展;护理诊断的目标与发展;护理诊断的分类与发展;护理诊断在我国的应用与发展以及如何作出护理诊断五个方面综述了护理诊断的发展过程及重要性。  相似文献   
23.
BACKGROUND AND PURPOSE: Birth certificates are a major source of population-based data often used in maternal and child health research, but their value depends upon the level of accuracy of the data. The purpose of this study was to assess the validity of the birth registry data in Taiwan. METHODS: Obstetric records of a total of 2779 infants born at a municipal hospital in Taipei between 1995 and 1997 were abstracted and linked to the Taiwan Birth Registry (TBR). Concordance was presented by agreement percentages for various birth characteristics including gender, birth order, birth weight, and gestational age. Concordance was further assessed using Cohen's k and sensitivity/specificity for both birth weight and gestational age, with both variables categorized according to their customary definitions. RESULTS: Missing data for specific items in the TBR ranged from 0% (gender) to 1.6% (birth order). The birth registry accurately reported all 4 selected items, with the highest and lowest concordance percentage noted for gender (99.0%) and gestational age (88.3%), respectively. The level of agreement indicated by the Cohen's k statistic ranged from 0.92 to 0.96 for birth weight and gestational age when both variables were treated as categorical variables. CONCLUSIONS: The TBR showed a low rate of missing information and high levels of validity for the elements frequently used in maternal and child health research in Taiwan.  相似文献   
24.
主要通过医学生的视角,从教学内容、教学方法等方面谈了对医学伦理学教育的感受和一些建议,并通过医学生的声音反映医学伦理学教育的成果以及存在的一些问题。  相似文献   
25.
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   
26.
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   
27.
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   
28.
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   
29.
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   
30.
发育性偏颌畸形的整形外科矫治   总被引:2,自引:1,他引:1  
目的探讨发育性偏颌畸形的外科矫治方法。方法通过对21例发育性偏颌畸形患者的畸形部位与程度,分别采用LefortⅠ型截骨、下颌升支矢状劈开、颏部水平截骨、下颌骨外板截除、下颌骨外板移植等项整形手术治疗,并就该类患者颌面结构特征、手术方式的选择及疗效进行了回顾性分析。结果自1997年7月至2003年10月共治疗发育性下颌偏斜畸形21例,根据不同的类型采用相应的手术方法,获得了满意面部形态和殆功能。结论发育性偏颌畸形,根据不同类型运用相应的措施,通过恢复面部骨性轮廓支架和殆关系,配合术前术后的正畸治疗,可获得满意的临床效果。  相似文献   
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