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81.
活血化瘀中药联合血管内皮生长因子基因转移促进股骨头坏死处新生血管形成的实验研究 总被引:5,自引:4,他引:1
目的:观察活血化瘀中药联合血管内皮生长因子(VEGF)基因转移对促进股骨头缺血坏死处新生血管形成情况。方法:日本大耳兔40只,随机分为对照组、模型组、中药组、基因组和综合组。治疗8周后采用免疫组织化学方法观察股骨头滑膜VEGF阳性细胞率及数字减影血管造影股骨头血管数目改变情况。结果:模型组VEGF阳性细胞表达率减低,与对照组、基因组、综合组比较,差异有显著性意义(P<0.01),与中药组比较,有统计学差异(P<0.05),综合组VEGF阳性细胞表达率较高,与中药组及基因组比较,有统计学差异(P<0.05)。血管数目:在A区,各组与模型组比较,均无统计学差异;在B区,各组较模型组血管数目均有增加,对照组、基因组、综合组与模型组比较,有统计学差异(P<0.05)。综合组与基因组比较有统计学差异(P<0.05),中药组虽然血管数目较模型组多,但是无统计学意义。结论:活血化瘀中药及VEGF基因转移均可促进股骨头缺血坏死处局部新生血管形成和侧支循环的建立,尤以活血化瘀中药联合基因疗法效果为好,为临床应用活血化瘀中药联合基因疗法治疗股骨头缺血性坏死提供实验依据。 相似文献
82.
83.
目的用彩色多普勒超声观察穿刺性血管损伤的声像图特征。方法26例周围血管穿刺后出现局部肿块、血管杂音,用彩色多普勒超声显示肿块的形态、回声、与周围血管的关系,观察肿块内、破口处、肢体动脉和静脉内的血流信号。结果3例单纯性血肿,彩色血流成像肿块内无血流信号;19例假性动脉瘤,肿块内有低速的动脉血流信号,动脉与肿块的破口处有五彩镶嵌的彩色血流信号和收缩期高速湍流血流频谱;4例动静脉瘘,在瘘口处可见有一股五彩镶嵌的彩色血流信号和连续性高速分流频谱。结论彩色多普勒超声能为穿刺性血管损伤提供准确的诊断。 相似文献
84.
经皮椎体成形术中骨水泥填充对患者凝血功能的影响 总被引:3,自引:0,他引:3
目的:探讨经皮椎体成形术中骨水泥对骨质疏松性椎体压缩骨折患者凝血功能的影响及临床意义.方法:2006年12月至2007年12月,对24例骨质疏松性椎体压缩骨折患者行经皮椎体成形术,男6例,女18例:年龄48~83岁,平均69岁.脊柱骨折部位为T5-L3,共44个椎体,其中胸椎20个椎体,腰椎24个椎体.采用C型臂X线机透视引导下行经皮椎体成形术,注射聚甲基丙烯酸甲酯骨水泥(PMMA).分别在注入骨水泥前10min、注入骨水泥后10min、30min、1h、2h及3h时检测患者凝血功能相关指标,包括血浆凝血酶原时间(PT)、活化的部分凝血活酶时间(APTT)、凝血酶时间(TT)、纤维蛋白原(FIB)、鱼精蛋白副凝固试验(3P试验)及血浆D-二聚体(D-D)含量,并进行统计学分析.结果:经皮椎体成形术中注人骨水泥10min后PT缩短、FIB增高、3P试验阳性率升高,D-D含量增高,1h时达到高峰后开始下降.注入骨水泥后10min、30min、1h、2h四个时间点与注入骨水泥前相比较均有显著性差异(P<0.05).活化的部分凝血活酶时间(APTT)、凝血酶时间(TT)在各时间点与注入骨水泥前比较均无显著性差异(P>0.05).3h后骨水泥对这些指标的影响基本消除,各项指标与注入骨水泥前比较均无显著性差异(P>0.05).结论:经皮椎体成形术中骨水泥填充会引起患者一过性血液高凝状态,在注入骨水泥后的3h内需严密监测病情,以防血栓性疾病发生. 相似文献
85.
Amos Zeichner Peter R. Giancola Joseph D. Allen 《Alcoholism, clinical and experimental research》1995,19(4):977-983
The purpose of this study was to compare the stress-response-dampening (SRD) effect of alcohol in hostile and nonhostile men based on a combined score of four subscales of the Cook-Medley Hostility Scale . Subjects were 72 male social drinkers. Subjects' cardiac interbeat-interval, and systolic and diastolic blood pressure reactivity to a situational stressor were measured following the consumption of either alcohol, no alcohol, or an active placebo beverage. Results demonstrated that hostile men evinced lower heart rate and systolic blood pressure (SBP) reactivity to the stressor when given alcohol, compared with intoxicated nonhostile subjects, and lower reactivity relative to all other groups, with the exception of SBP in the nonhostile controls. These results allow for speculation that hostile men may be more likely than controls to experience possible SRD effects of alcohol and thus, perhaps, be predisposed to increased alcohol consumption when under stress. 相似文献
86.
Czeslaw J. Lewa Jacques D. de Certaines 《Journal of magnetic resonance imaging : JMRI》1995,5(2):242-244
Mechanical waves in magnetic resonance imaging, which have been suggested for possible clinical applications, were analyzed with regard to imaging of the viscoelastic properties of large objects. The method is based on the Larmor frequency modulation caused by the application of mechanical waves. Possible clinical applications include all diseases that result in a change in the mechanical properties of biologic tissues (eg, atherosclerosis). 相似文献
87.
医院用血液制品HCV污染情况的调查 总被引:1,自引:0,他引:1
目的调查医院治疗用血液制品HCV污染情况.方法临床治疗所用的血液制品,在输完后留容器之残液备检.采用酶标免疫法(ELISA)检测.对ELISA检测之阳性标本及在阴性标本中随机抽取9份,采用逆转录双PCR方法检测HCV_RNA.结果血浆白蛋白抗_HCV阳性率458%,新鲜血浆阳性率26%.两种方法检测同一标本,ELISA检测阳性的血液制品中,用PCR证实,并非都有病毒复制;而在ELISA检测的阴性标本中,仍旧有较高的PCR阳性检出.结论血液制品存在着HCV污染,抗_HCV对于HCV感染的诊断价值很高.检测血液制品中的抗_HCV,合理使用血液成份,可防止HCV在医院内传播. 相似文献
88.
Abstract. This study examined the ability of nitrova-sodilator treatment with isosorbide dinitrate to prevent the development of reduced nerve conduction velocity and nutritive blood flow in streptozotocin-induced diabetes mellitus in rats. Two month untreated diabetes caused approximately 23% and 13% reductions in sciatic motor and saphenous nerve sensory conduction velocity ( P < 0.001). Isosorbide dinitrate treatment provided 64.6 and 67.6% protection for motor and sensory nerves, respectively ( P < 0.01). Sciatic endoneurial nutritive blood flow was measured by microelectrode polarography and a hydrogen clearance technique. After 1 month untreated diabetes, flow was reduced by 41.9% ( P < 0.001). Isosorbide dinitrate treatment for 1 month in non-diabetic and diabetic rats significantly increased blood flow ( P < 0.01). When between-group variations in blood pressure were taken into account, vascular conductance increased by 29% and 31% in non-diabetic and diabetic rats, respectively ( P < 0.01). Thus, nitrovasodilator treatment improves nerve perfusion and function in experimental diabetes, probably by compensating for reduced endothelium-derived nitric oxide release or action. 相似文献
89.
Takahiro Narishige Kensuke Egashira M.D. Yutaka Akatsuka Teisuke Takahashi Akira Takeshita 《Cardiovascular and interventional radiology》1993,16(6):343-347
The effects of an intracoronary administration of iomeprol, a new nonionic tri-iodinated water-soluble contrast medium, on
coronary circulation were compared to those of iopamidol and those of nitroglycerin in 6 chronically instrumented conscious
dogs. A pair of 10 MHz piezoelectric crystals and an electromagnetic flow probe were placed on the left circumflex coronary
artery (LCCA) to measure the epicardial coronary diameter (CD) and coronary blood flow (CBF). Polyethylene tubing for drug
administration was inserted into the LCCA proximal to the sonomicrometers. Iomeprol at the dose of 1 ml and 3 ml/min for 1
min significantly increased CD by 0.6±0.1% and 1.4±0.3%, respectively and CBF by 44.5±9% and 70±10%, respectively. Iopamidol
at the same rates also significantly increased CD by 0.8±0.1% and 1.5±0.3% and CBF by 50±11% and 82±14%, respectively. There
was no statistically significant difference between iomeprol-and iopamidol-induced increases in CD and CBF. However, the duration
of the increase in CD was significantly shorter (p<0.05) after iomeprol than after iopamidol. Nitroglycerin (10 μg/kg) significantly increased CD by 4.5±1% and CBF by 105±10%.
The increases in CD and CBF in response to iopamidol and iomeprol were significantly smaller (p<0.01) than to nitroglycerin. We conclude that vasodilating effects of iomeprol and iopamidol on the large epicardial coronary
artery and coronary blood flow are comparable in conscious dogs and significantly lower than after nitroglycerin in the doses
used by us.
This study was supported by a grant from the EI-ZA1 Pharmaceutical Co., Tokyo, Japan. 相似文献
90.
In order to evaluate the pump output control based on the oxygen delivery to peripheral tissues, arterial and mixed venous hemoglobin content ([Hb]) and oxygen saturation (SO2) were continuously monitored in three biventricular bypass animals (3-, 6-, and 40-day experiments) with fibrillating ventricles. The specially developed oxygen sensors were mounted in the outflow ports of the artificial hearts to measure [Hb] and SO2. One animal was exercised on the treadmill at 2.0 mile/h for 15 min with pump flows fixed to deliver oxygen of (a) above 13 cc/min/kg, (b) 10, and (c) 9. In (a), the mixed venous saturation (SvO2) dropped to approximately 25% with no increase in the blood lactate level. In (b) and (c), the SvO2 decreased to approximately 10-15% with increase in blood lactate levels from 4 to 10-30 mg/dl. Also, the recovery of the SvO2 in these groups following the termination of the exercise was slower in comparison to (a). The lower limit of the SvO2 level that would create oxygen debt situation in the peripheral tissues was approximately 25-30% for the exercise of 2.0 mile/h. The SvO2 reflects changes in respiratory status, pump output, hemoglobin level, and metabolism, and is thus a useful indicator to diagnose quickly the circulatory status as well as possibly to control the artificial heart output. 相似文献