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51.
The incidence of thromboembolitic events in patients undergoing transfemoral angiography was examined using indium-111 labeled platelets. Twenty-seven patients received approximately 300 muCi of autologous labeled platelets at least 3 hours before angiography and were scanned with a gamma camera immediately before and after angiography. All patients were free of clinically obvious complications in the 1-2 day period after angiography. Our results showed evidence of platelet deposition at 21 sites other than the puncture site in 12 (44%) patients. Most platelet deposition (54%) occurred along the region between the puncture site and the aortic bifurcation; 24% occurred at sites not traversed by the catheter. At the puncture site itself, there was substantial platelet uptake in 44% of patients. This study indicates the need for further work in determining the most suitable catheter material and in assessing the efficacy of other measures such as anticoagulant or antiplatelet therapy. 相似文献
52.
本文用DSC和激光拉曼光谱研究抗癌药物足叶乙甙(4-去甲基表鬼臼毒素-β-D-乙叉吡喃葡萄糖甙,简称VP 16-213)与二棕榈酰磷脂酰胆碱(DPPC)脂质体的作用。VP 16-213分子掺入DPPC脂质体双层中,不但使相转变温度向高温移动,而且吸热峰的半高宽度随VP 16-213浓度增加而变宽。其Raman光谱在频率2850 cm~(-1)处的C-H键对称伸缩振动亦随着药物浓度增加而减弱。这些结果表明VP 16-213分子是定域在脂双层中DPPC分子链的C_1~C_9亚甲基区域,使脂质体的有序性提高而流动性降低。 相似文献
53.
老年大鼠松质骨骨重建的组织形态计量学研究 总被引:1,自引:0,他引:1
目的:研究老年大鼠及在促骨合成药前列腺素E2(PGE2)作用下松质骨骨重建和骨建造的形态计量学改变,探讨动物骨重建形态学新参数测量方法及其意义。方法:50只20月龄雄性Wistar大鼠随机分成5组,年龄对照组(基础组、10d和30d年龄对照组),PGE2给药组(分别10d和30d给予3mg/kg/d处理组)。用体内双荧光标记,不脱钙组织切片,粘合线(cement line)染色,骨组织形态计量学方法,测定骨重建和骨建造参数。结果:20月龄雄性大鼠胫骨近端松质骨的形成表面大多数为骨重建单位(占63.3%),少部分为骨建造单位(占26.7%);PGE2用药后骨重建单位增加1.5倍,骨建造单位增加4倍,比值倒置,成骨细胞10d时明显增多。说明PGE2通过刺激成骨细胞骨合成而介民导骨建造性骨增加和骨重建性骨量增加,并以前为主。结论:老年雄性大鼠 松质骨以骨重建活动为主,仍有骨建造活动。PGE2主要通过刺激成骨细胞骨建造而增加骨量。 相似文献
54.
I. A. NÆSS S. C. CHRISTIANSEN† P. ROMUNDSTAD‡ S. C. CANNEGIETER† F. R. ROSENDAAL†§ J. HAMMERSTRØM 《Journal of thrombosis and haemostasis》2007,5(4):692-699
Background: Estimates of the incidence of venous thrombosis (VT) vary, and data on mortality are limited. Objectives: We estimated the incidence and mortality of a first VT event in a general population. Methods: From the residents of Nord‐Trøndelag county in Norway aged 20 years and older (n = 94 194), we identified all cases with an objectively verified diagnosis of VT that occurred between 1995 and 2001. Patients and diagnosis characteristics were retrieved from medical records. Results: Seven hundred and forty patients were identified with a first diagnosis of VT during 516 405 person‐years of follow‐up. The incidence rate for all first VT events was 1.43 per 1000 person‐years [95% confidence interval (CI): 1.33–1.54], that for deep‐vein thrombosis (DVT) was 0.93 per 1000 person‐years (95% CI: 0.85–1.02), and that for pulmonary embolism (PE) was 0.50 per 1000 person‐years (95% CI: 0.44–0.56). The incidence rates increased exponentially with age, and were slightly higher in women than in men. The 30‐day case‐fatality rate was higher in patients with PE than in those with DVT [9.7% vs. 4.6%, risk ratio 2.1 (95% CI: 1.2–3.7)]; it was also higher in patients with cancer than in patients without cancer [19.1% vs. 3.6%, risk ratio 3.8 (95% CI 1.6–9.2)]. The risk of dying was highest in the first months subsequent to the VT, after which it gradually approached the mortality rate in the general population. Conclusions: This study provides estimates of incidence and mortality of a first VT event in the general population. 相似文献
55.
Evaluation of atypical human immunodeficiency virus immunoblot reactivity in blood donors 总被引:6,自引:0,他引:6
NL Dock ; HV Lamberson Jr ; TA O''Brien ; DE Tribe ; SS Alexander ; BJ Poiesz 《Transfusion》1988,28(5):412-418
Blood donors reactive by enzyme-linked immunosorbent assay for antibody to the human immunodeficiency virus (HIV) who showed atypical patterns of viral core protein reactivity on Western blot were monitored for several months. Characterization of their antibodies was performed by 1) use of recombinant HIV proteins; 2) determination of cross-reactivity to HTLV-I, HTLV-II, and HTLV-IV: 3) assessment of immune status; and 4) identification of potentially interfering autoantibodies. Nineteen of 20 donors maintained the same HIV antibody reactivity throughout the follow-up period; the other donor became fully antibody-positive. Eighteen of 20 donors' sera showed clear reactivity with HIV recombinant core proteins. Ten of 19 donor samples demonstrated cross-reactivity to HTLV-IV; 3 of these 10 also cross-reacted with HTLV-I. The immune status of all donors was normal, although the medical histories and HLA antibody screens suggested possible autoimmune reactivity in 9 of 18 donors. During follow-up interviews, three donors reported possible risk factors for HIV infection that had not been acknowledged at the time of blood donation. We conclude that exclusion of donors with these atypical serologic test results is warranted while further studies to determine significance are being conducted. 相似文献
56.
57.
对QT离散度实质的探讨 总被引:2,自引:0,他引:2
为探讨QT离散度(QTd)的真实意义,观察139例急性心肌梗死(AMI,AMI组)及109例正常人(对照组)的最长QT间期(QTmax)、校正QTmax(QTcmax)及QTd的变化。结果:①AMI组的QTmax、QTcmax和QTd均显著高于对照组(分别为422.60±30.51msvs382.46±23.40ms、460.21±28.96msvs388.51±20.15ms、59.80±28.40msvs39.43±12.21ms,P均<0.001)。②AMI组中发生严重室性心律失常(VA)患者(114例)的QTmax、QTcmax、QTd与无VA的患者(25例)相比,均有显著差异(分别为448.58±33.40msvs416.10±35.30ms、481.43±35.17msvs439.60±27.10ms、66.90±20.72msvs48.32±23.61ms,P均<0.001)。认为AMI时QTd系T向量环在不同导联上的“投影”差异所引起的,其异常的本质是QT间期延长 相似文献
58.
目的:已有理论提出急性心肌梗死后骨髓和外周血中的CD34 干细胞具有自身动员的潜能,观察这一潜能的变化特征及其对心肌梗死组织再生能力的影响。方法:实验于2004-09/2005-02在阜外心血管病医院完成。①实验动物:雄性SD大鼠40只,随机数字表法分为心肌梗死组、假手术组,20只/组。②实验方法:心肌梗死组大鼠采用冠状动脉结扎法建立心肌梗死模型。心电图ST段抬高或有室性心律出现,前壁心肌呈苍白色为造模成功。假手术组仅作开胸手术,前降支不予结扎。③实验评估:于心肌梗死后3,7,14,28d,流式细胞仪检测骨髓和外周血中CD34 干细胞的含量。用免疫组化方法检测梗死心肌组织中的Ki67细胞和毛细血管数量。结果:①外周血及骨髓CD34 干细胞含量的变化:心肌梗死组外周血中的CD34 干细胞数量于造模后3d开始上升,7d后明显高于假手术组(P<0.01),至14,28d时逐渐回落至假手术组水平(P>0.05)。心肌梗死组骨髓中的CD34 干细胞数量于造模后各时间点始终无明显变化(P>0.05)。②组织学评定:心肌梗死组梗死区Ki67细胞和毛细血管数量于造模后3d开始增多,7d时明显多于非梗死区(P<0.05);至14,28d梗死区Ki67细胞数量明显少于造模后7d(P<0.05),毛细血管数量的减少不明显(P>0.05)。免疫组化染色显示少数Ki67细胞分化为血管内皮细胞,未见向心肌细胞分化。③相关性分析:梗死区Ki67细胞、毛细血管数量于造模后7d与外周血中CD34 干细胞数量呈显著正相关(r=0.913,P=0.021;r=0.887,P=0.035)。结论:机体CD34 干细胞的自体动员、增殖反应的潜能随急性心肌梗死时间的延长而逐渐减弱,自体动员的干细胞功能尚不足以达到修复梗死心肌组织的效果。 相似文献
59.
Transfusion practice in central Virginia 总被引:4,自引:0,他引:4
60.
ABM Kharsany N Hancock JA Frohlich HR Humphries SS Abdool Karim Q Abdool Karim 《HIV medicine》2010,11(10):661-665