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991.
A recent development in antithrombotic research allows the inhibition of platelet aggregation via protection of the glycoprotein IIb/IIIa receptor on the platelet membrane. We hypothesized that a GP IIb/IIIa receptor inhibitor would inhibit thromboxane-induced platelet aggregation during circulation in our in vitro ventricular assist device (VAD) circuit and preserve long-term platelet function. Twenty-one in vitro nonpulsatile centrifugal VAD circuits were simulated for 4 days using 450 ml of fresh human whole blood with or without glycoprotein IIb/IIIa receptor inhibitor (tirofiban). Platelet aggregation and degranulation were measured in whole blood induced by ristocetin, collagen, ADP, and thromboxane A2 (TXA2). The tirofiban-treated group preserved the platelet count and tended to exert these beneficial effects by inhibiting pathologic platelet aggregation induced by TXA2, collagen, and ADP as well as degranulation. Tirofiban may be useful in preserving platelet number and function during clinical VAD use. 相似文献
992.
993.
乳腺部患者手术创面冲洗液细胞学检查的价值 总被引:1,自引:0,他引:1
目的 观察乳腺癌患者手术创面脱落癌细胞与临床病理分期的关系,为术中采用杀来脱落癌细胞的措施提供依据。方法 对262例乳腺癌患者手术创面冲洗液进行细胞学检查,并将结果与临床病理分期做对比分析。结果 本组虱脱落癌细胞阳性者63例,占24%。Ⅰ、Ⅱ、Ⅲ、Ⅳ期乳腺癌患者脱落癌细胞检出率分别为5.3%、27.1%、79.3%100%。T1、T2和T3以上者,脱落癌细胞检出纺分别为6.1%、18.9%、561 相似文献
994.
OBJECTIVES: To observe the role of the engineered growth plate (EGP) in the treatment of premature arrest of growth plate and to establish a novel treatment method for the premature arrest of the growth plate. METHODS: The engineered growth plates were cultured for the first time by using polylactic acid (PLA) as cell scaffold seeded with growth plate chondrocytes and they were implanted into the medial proximal defects of growth plates of New Zealand rabbit tibia. The degree of deformity of the tibia was evaluated by X-ray and the expression of collagen II mRNA of regenerating growth plate was detected by in situ hybridization technique. RESULTS: Little deformity appeared in the EGP group 8 weeks after operation. Some deformity was seen in the EGP group 16 weeks after operation, whereas it's degree was much less than that of the control group (P = 0.0001). The degree of the angular deformity of the EGP precultured with bFGF and TGF-beta group was less than that of the EGP group (P < 0.05). The cells in the regenerating growth plate arranged in column and were stained blue by in situ hybridization technique. CONCLUSION: The EGP can prevent the formation of bony bridge and restore the growth of the damaged growth plate. 相似文献
995.
放疗增敏剂甘氨双唑钠的Ⅱ期临床研究 总被引:19,自引:0,他引:19
目的 :按二期临床研究要求观察注射用甘氨双唑钠 (简称CMNa)的有效性和安全性。方法 :采用平行对照、随机分组的设计方法 ,将 2 8例经病理组织学确诊的需接受放射治疗的头颈部、食管和肺部肿瘤患者 ,按 2∶1的比例分设实验组(CMNa +常规放疗 )和对照组 (单纯常规放疗 ) ,观察其有效性和安全性的相关指标。结果 :治疗前后血常规、肝肾功能的实验室检查 ,治疗中和治疗后不良反应、严重程度的观察比较及不良反应率的结果比较。两组均无显著性差异。肿瘤原发灶和转移灶的CR率和CR +PR率两组未见显著性差异。但转移灶达PR时所需的照射剂量明显低于对照组 (P <0 0 5 )。结论 :安全性与前期研究结果相符 ,在临床推荐剂量内未观察到明显消化道和神经系统等的不良反应 ,有效率未见显著性差异可能与样本数较少有关。据后期汇总的大样本统计显示两组的显著性差异表现在CMNa可提高CR率和总有效率 ,并降低达到CR和PR时的照射剂量 相似文献
996.
目的: 建立人单核巨噬细胞泡沫化抑制剂筛选模型,筛选得到可抑制细胞泡沫化的抑制剂.方法: U937单核细胞经100 nmol·L-1佛波酯(PMA)诱导72 h分化为巨噬细胞后,换无血清培养液于96孔板中,每毫升含巨噬细胞1×106个,每孔再加入80 mg·L-1氧化的低密度脂蛋白(ox-LDL),37 ℃培养48 h,建立单核巨噬细胞泡沫化模型.利用微生物发酵液,或单一的化合物样品与其共孵育,油红.染色后观察细胞胞内变化,寻找对泡沫细胞形成有抑制作用的样品.利用基因工程技术表达的人清道夫受体A类II型的胞外部分,在本模型中可抑制巨噬细胞泡沫化的形成,进一步验证了模型的可行性.结果: 从2000 个微生物发酵液中筛选到6株微生物发酵液为阳性,从10个化合物中发现一个有抑制巨噬细胞泡沫化活性的新化合物.结论: 本模型可用于细胞泡沫化抑制剂的高通量筛选. 相似文献
997.
288例老年呼吸道感染患者病原菌分布特性及药敏分析 总被引:4,自引:1,他引:4
目的: 了解老年呼吸道感染患者病原菌的分布特点及药敏特性.方法: 对288例老年呼吸道感染患者痰样本(NCCLS法)进行细菌培养,K-B纸片法进行药敏测定.结果: 患者痰中共检出病原菌400株,细菌280株,其中G-杆菌147株,占36.75%, G 球菌133株,占33.25%.肺炎克雷伯菌及铜绿假单胞菌最敏感药的是头孢他啶,敏感率均为40%以上,肺炎链球菌和金黄色葡萄球菌最敏感药的是万古霉素;检出真菌120株,占30%,以白色念珠菌为主.结论: 进行病原菌跟踪监测及时的药敏试验,对及时控制老年呼吸道感染,是不可缺少的重要环节. 相似文献
998.
目的:建立HPLC法测定清热除湿合剂中黄芩苷的含量。方法:用Supelcosil LC-18-DB(4.6mm×150 mm,5 μm)色谱柱,流动相:甲醇-水-磷酸溶液(48:52:0.2),流速1.0ml·min-1,检测波长280 nm。结果:黄芩苷在0.237~9.472μg范围内与峰面积线性关系良好,回归方程为A=1.332×104 1.456×105C(r=0.999 9,n=7),平均加样回收率为100.48%,RSD为1.06%。结论:本法测定简便,结果准确,重现性和分离度好,可用于清热除湿合剂的质量控制。 相似文献
999.
目的观察前列腺素E1脂微球载体制剂(Lipo-PGE1)治疗肝硬化大量腹水的疗效.方法选择肝硬化大量腹水84例,分为两组,治疗组42例,用Lipo-PGE1联合综合护肝+利尿剂治疗;对照组42例采用综合护肝+利尿剂治疗.结果治疗组对肝硬化大量腹水治疗显效率和总有效率显著高于对照组(P<0.001).Lipo-PGE1治疗前后的丙氨酸转氨酶(ALT)、天门冬酸氨基转移酶(AST),总胆红素(SB)、肌酐(Cr)等指标均在疗程结束时得到显著改善(P<0.01).结论
Lipo-PGE1有一定退腹水作用,且具有保护肝细胞、促进肝细胞再生的作用. 相似文献
1000.
Insight into the mechanism by which estradiol improves organ functions after trauma-hemorrhage 总被引:3,自引:0,他引:3
BACKGROUND: Recent studies have indicated that female rodents with high levels of estradiol (proestrus) have better organ functions after trauma-hemorrhage than females with low estradiol levels (estrus) or male animals. However, the precise role of estrogens in maintaining organ function after hemorrhage remains unknown. METHODS: Adult female Sprague-Dawley rats were ovariectomized 14 days before the experiment to decrease circulating levels of estradiol. Animals underwent laparotomy to induce tissue trauma and were then bled to and maintained at a mean arterial pressure of 40 mm Hg until 40% of the maximal bleed-out volume was returned in the form of Ringer's lactate. Resuscitation was carried out with 4 times the volume of maximal bleed-out with Ringer's lactate during a period of 1 hour. 17beta-Estradiol (E2, 1 mg/kg body weight intravenously) with or without a specific estrogen receptor antagonist ICI 182,780 (3 mg/kg body weight intraperitoneally) was given at the beginning of resuscitation. At 24 hours after hemorrhage and resuscitation, cardiovascular and hepatocellular functions (ie, the maximal velocity and overall efficiency of indocyanine green clearance) were determined. Plasma E2 was also assayed. The effects of ovariectomy and E2 administration on uterine weight were measured in additional groups of animals. RESULTS: The results indicate that cardiovascular and hepatocellular organ functions were significantly depressed after trauma-hemorrhage and were restored in animals receiving E2. However, simultaneous administration of its specific receptor antagonist abolished the salutary effects of E2 treatment despite high circulating levels of E2. Uterine weight decreased at 14 days after ovariectomy, which was partially restored with a single dose of E2. CONCLUSIONS: Administration of 17beta-estradiol should be considered a novel and safe adjunct for ameliorating hemorrhage-induced organ dysfunctions in ovariectomized and postmenopausal women because of their low estradiol levels. 相似文献