Effect of platelet-activating factor (PAF) on human platelets

The effect of pure synthetic PAF (1-0-alkyl-2-acetyl-sn-glycero-3- phosphorylcholine) was studied in human platelets. PAF (0.2--2.0 micrograms/ml) produced a dose-dependent aggregation in human platelet- rich plasma (PRP) or platelet suspension obtained by gel-filtration (GFP). In addition, PAF (0.8 microgram/ml) induced secretion of 14C- serotonin (45% +/- 10%; mean +/- SD, n = 9) and platelet factor 4 (PF4) (12.89 +/- 3.81 micrograms/10(9) platelets; n = 9) in PRP. Similar results were obtained in GFP. Aggregation and release of 14C-serotonin and PF4 were inhibited by the metabolic inhibitors 2-deoxyglucose (16.7 mM) and antimycin-A (8.3 micrograms/ml), by the membrane-active drugs mepacrine (10 microM) and chlorpromazine (0.025 mM), by PGI2 (5.34 nM), which elevates intracellular c-AMP, by indomethacin (10 microM) or aspirin (100 microM). The ADP scavengers, creatine phosphate and creatine phosphokinase (CP/CPK), inhibited the second wave of aggregation but not secretion. These data suggest that the major effect of PAF on human platelets is mediated through the cyclo-oxygenase pathway and not through a third pathway.     

大学生焦虑的类型及其相关因素

目的:总结分析大学生焦虑的研究现状,为开展相关研究提供思路。方法:应用计算机检索Medline1979-01/2005-12关于大学生焦虑的文章。检索词"university students,anxiety"并限定文章的语言种类为英语。同时利用计算机检索中国期刊全文数据库1979-01/2005-12的相关文章,限定文章语言种类为中文,检索词"大学生焦虑"。结果:焦虑是大学生中普遍存在的心理问题。其中考试焦虑、学习焦虑、社交焦虑、毕业生的焦虑、特质焦虑、贫困大学生的焦虑、军队大学生的焦虑、医学大学生的焦虑以及不同年级、性别、专业及城乡差别大学生的焦虑是大学生焦虑中最为严重的几个方面。许多心理专家学者为大学生的各种焦虑问题的原因进行了分析,并提出了解决方案和对策。结论:大学生的焦虑已成为影响大学生生活学习的重要不利因素,需要学校、社会、家庭及个人采取有效的方法来缓解并消除这种焦虑情绪,从而为大学生学习及毕业后能更好的适应纷繁复杂的社会打下良好的基础。     

幼年豚鼠视网膜兴奋毒性损伤模型的建立

目的:观察谷氨酸钠不同给药时程对幼年豚鼠视网膜神经节细胞损伤的程度,以建立简便而稳定可靠的视网膜兴奋毒性损伤模型。方法:实验于2005-03/2006-06在泰山医学院动物实验中心和形态学实验室完成。①实验材料:45～50d(幼年)豚鼠35只,体质量280～320g,雌雄不拘;谷氨酸钠(上海伯奥生物科技有限公司生产),纯度99%,pH6.9～7.2,用生理盐水配成300g/L溶液。②实验分组:采用随机数字法将豚鼠分成2组,即正常对照组5只、谷氨酸钠组30只(谷氨酸钠组根据用药时间又分为4个亚组,即1d组5只、3d组6只、7d组9只,14d组10只)。③实验干预:谷氨酸钠组按3g/kg体质量腹腔注射谷氨酸钠,分别连续1,3,7和14d。④实验评估:给药后,再饲养10d后取材,观察视网膜神经节细胞数目和形态学的变化。结果:①各组豚鼠视网膜光镜观察结果:谷氨酸钠1d组视网膜神经节细胞未见明显形态学改变;3d组少数细胞发生皱缩;7d组视网膜神经节细胞损伤较为明显,多数神经节细胞发生核固缩;14d组动物半数死亡(5/10),视网膜神经节细胞损伤严重,明显脱失,残留细胞体积变小。②各组豚鼠视网膜神经节细胞密度:谷氨酸钠14d组、7d组视网膜神经节细胞密度与正常对照组比较差异均显著(P<0.01),谷氨酸钠3d组与正常对照组比较差别有统计学意义(P<0.05),谷氨酸钠1d组与正常对照组比较差异无显著性(P>0.05)。结论:谷氨酸钠对幼年豚鼠视网膜的毒性损伤与用药时程有关,按3g/kg体质量腹腔注射,1次/d,连续7d,能成功建立谷氨酸视网膜兴奋毒性豚鼠动物模型,且无一例死亡,损伤适中。     

心肌肌钙蛋白Ⅰ、肌红蛋白和肌酸激酶同工酶在老年急性心肌梗死中的检测及意义

目的 探讨心肌肌钙蛋白Ⅰ( cTnⅠ)、肌红蛋白(Mb)和肌酸激酶同工酶(CK-MB)在老年急性心肌梗死(AMI)中的变化及意义。方法 分别检测89例AMI患者（AMI组）和100例体检的健康人(对照组)cTnⅠ、Mb、CK-MB水平,并进行比较。结果 AMI组cTnⅠ、Mb、CK-MB水平分别为(8.15±3.26)μ g/L、(478.45±96.87)μg/L和(128.17±53.26) U/L,而对照组分别为（0.03±0.02）μg/L、(21.61±9.38)μg/L和(9.53±2.94) U/L,AMI组cTnⅠ、Mb、CK-MB水平显著高于对照组(P＜0.05)。cTnⅠ、Mb、CK-MB检测AMI的敏感度分别为95.5％( 85/89)、97.8％( 87/89)和87.6％( 78/89),特异度分别为98.0％(98/100)、82.0％( 82/100)和94.0％(94/100)。结论 cTnⅠ、Mb和CK-MB水平在老年AMI患者中明显升高,其中cTnⅠ在诊断AMI时具有很高的敏感度和特异度。     

Recurrent pterygia: results of postoperative treatment with Sr-90 applicators

Recurrent pterygia in 42 patients (48 eyes) were treated locally with strontium-90 irradiation from May 1967 to May 1988. The 31 male patients had an average age of 52 years; the 11 female patients, 46 years. All patients underwent surgical resection of the recurrent pterygia with use of the bare-sclera technique. During the immediate postoperative period the surgical site was treated with an Sr-90 applicator (beta irradiation). Doses ranged from 10 to 70 Gy (average, 50 Gy). Follow-up times ranged from 8 to 136 months (median, 14 months). The local control rate was 89%. Four of the five recurrences were in patients treated with doses of 1,000-1,500 cGy (P less than .0002). None of the patients developed cataracts or any other serious complications.