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21.
Objective To investigate the dynamic changes of intercellular adhesion molecule-1 (ICAM-1) expression in endothelial cells (EC) during hindlimb allograft acute rejection in rats and the inhibitory effect of cyclospofine A (CsA) on the acute rejection. Methods The rat model of hindlimb allograft was developed. The rats were randomly divided into following groups: control group (Wistar→Wistar), rejection group ( Sprague-Dawley→Wistar) and CsA-treated group (Sprague-Dawley→Wistar). At postoperative day 1, day 4 and day 7samples of the femoral artery from the allograft limb were harvested to observe the pathologic changes. ICAM-1 expression in EC was quantified using immunohistochemical assay. Results Slight swelling and weak ICAM-1expression of EC were observed in the control group. In the rejection groups, obvious EC swelling and massive lymphocyte infiltration were seen. ICAM-1 expression in EC was significantly stronger and elevated. In CsA-group only mild infiltration of lymphocytes was seen and ICAM-I expression in EC was also much weaker.Conclusion During rat hindlimb allograft acute rejection the expression of ICAM-1 in EC was closely related to the occurrence and development of acute rejection. CsA could reduce the expression of ICAM-1 in EC and hence inhibit acute rejection of composite allograft.  相似文献   
22.
微囊化异种甲状旁腺组织移植的研究   总被引:4,自引:0,他引:4  
目的探讨微囊化异种甲状旁腺(PTG)组织移植对Wistar大鼠甲状旁腺功能低下的治疗作用及微囊的通透性。方法 40只去甲状旁腺Wistar大鼠随机分为微囊组、非微囊组、空囊组、空白对照组。用海藻酸-钡交联微囊包裹兔甲状旁腺组织,移植至Wistar大鼠肾包囊。移植后每隔2周取血测血钙,移植后第16周取移植物进行透射电镜检查及T淋巴细胞、大鼠IgG抗体的免疫组织化学染色。结果微囊组移植后第4周血清钙由(1.62±0.04)mmol/L恢复至正常水平 (2.2~2.6)mmol/L,9例维持至观察期结束(P<0.01),非微囊组、空囊组及空白对照组血清钙差异无统计学意义(P>0.05)。第16周取出移植物检测显示移植物活性良好,微囊周围可见较多T 淋巴细胞浸润,囊壁及囊内IgG抗体染色阳性。结论海藻酸-钡交联微囊可对甲状旁腺组织起到有效的保护作用,使甲状旁腺组织较长时间存活并发挥正常功能。但海藻酸-钡交联微囊并未减轻受体免疫排斥反应的激活且未有效的免疫隔离IgG抗体。  相似文献   
23.
混合Poisson分布及其应用:疾病的统计分布(五)   总被引:4,自引:0,他引:4  
本文讨论了混合Poisson分布的性质、应用条件、参数的估计及混合Poisson分布阶数的确定,指出混合Poisson分布可用于混合样本的判别归类,并用Bayes的思想导出其判别归类方法。模拟试验结果表明:当混合Poisson分布中各部分的比例相差不大,而各部分的均值相差较大时,抽样效果和拟合效果越好,所得到的估计值越接近理论值;反之效果越差。  相似文献   
24.
目的 :了解冠心病患者外周循环单核细胞组织因子 (TF)表达与冠心病病情的关系 ;观察溶栓治疗对急性心肌梗死患者单核细胞TF表达的影响。方法 :测定了 2 2例稳定型心绞痛 (SA)患者 ,2 1例不稳定型心绞痛(UA)患者 ,1 5例急性心肌梗死 (AMI)患者用尿激酶溶栓前及溶栓后 ,1 8例健康人外周循环单核细胞组织因子阳性率。单核细胞组织因子阳性率测定用免疫荧光染色及流式细胞术。结果 :SAP组 ,UAP组和AMI组单核细胞TF阳性率高于对照组 ,UAP组和AMI组单核细胞TF阳性率高于SAP组 ,单核细胞TF阳性率与冠心病病情显著相关。急性心肌梗死患者溶栓后 2h单核细胞TF阳性率升高。结论 :外周血单核细胞TF的表达与冠心病病情严重程度密切相关 ;急性心肌梗死患者溶栓治疗后单核细胞TF的表达进一步增强 ,这可能是溶栓后凝血酶活化的原因之一。  相似文献   
25.
在这篇文章中,应用圆形分布法计算了泰安市1984—1985两年流行出血热的发病平均日期,分别为1984年11月5号和1985年11月11号,两年合计的平均发病日期为11月9号。另外,还分析了发病的年龄和职业。这将为预防工作提供准确的科学数据。  相似文献   
26.
应用皮瓣移植修复足跟部皮肤软组织缺损   总被引:9,自引:2,他引:7  
目的通过8种不同皮瓣的临床应用,总结足跟部皮肤软组织缺损的修复效果。方法采用了游离足背皮瓣、游离背阔肌皮瓣、游离肩胛皮瓣、桥式胫后动脉岛状皮瓣、桥式携带背阔肌皮瓣或桥式携带肩胛皮瓣、胫后动脉岛状皮瓣、胫后动脉皮支岛状皮瓣、跖底内侧动脉岛状皮瓣,对足跟部皮肤软组织缺损进行修复的临床应用。结果95块皮瓣修复足跟部皮肤软组织缺损,成活93块,成功率为97.9%。随访1~15年,治疗效果满意。结论应用皮瓣移植的方法,才能使足跟部皮肤软组织缺损得到有效的修复。  相似文献   
27.
目的 探讨齿槽裂修复治疗的目的、方法以及治疗时机的选择。方法 查阅1950年至2006年有关齿槽裂修复的文献,归纳文献中报道的不同方法,并评价其各自的优缺点。结果 齿槽裂修复的主要目的:关闭口鼻瘘;建立稳定、连续的上颌骨牙弓;为牙齿萌出提供基础;为上唇和鼻底提供稳定支架。主要治疗方法:植骨术;牵引成骨技术;组织工程骨和生长因子应用;引导骨再生技术。患者最佳的手术治疗时机是9~11岁时混合牙列期。结论 在9~11岁混合牙列期手术,以髂骨松质骨为移植材料被认为是修复齿槽裂的主要手段。牵引成骨技术、组织工程技术和引导骨再生技术,将是齿槽裂修复的新方向。  相似文献   
28.
Tissue distribution and pharmacodynamics of verapamil were evaluated during steady state intravenous (i.v.) infusion and after single dose intraperitoneal (i.p.) drug administration to female Sprague-Dawley rats. In one group of rats, verapamil was infused to a steady state concentration at which time animals were killed. Verapamil-induced decreases in mean arterial pressure (MAP) were monitored during infusion and correlated with concomitantly obtained plasma verapamil concentrations. Tissue (lung, liver, renal medulla, renal cortex, cardiac muscle, skeletal muscle, perirenal fat, brain stem, cerebral cortex, and cerebellum) and plasma samples were obtained immediately after animals were killed and verapamil and norverapamil concentrations determined. Another group of rats, after receiving i.p. verapamil, were killed at 1, 3, 5, 19, and 24 h. Elimination from each tissue evaluated was described by a first order process. Elimination half-life of verapamil was similar among plasma and tissues evaluated (1.5 to 2.2 h). The per cent verapamil not bound to plasma proteins was concentration-independent and similar between rats receiving i.p. (mean +/- S.D.) (2.28 +/- 0.72 per cent) and i.v. (2.08 +/- 0.03 per cent) verapamil. MAP and verapamil concentration in plasma (r = 0.75; p less than 0.01) and cardiac muscle (r = -0.82; p less than 0.01) were inversely correlated in a highly significant fashion during both i.v. and i.p. drug administrations. The tissue-to-plasma distribution ratio for verapamil and norverapamil was similar among animals receiving i.p. verapamil at all points of sampling, suggesting distribution equilibrium had been achieved. After steady state i.v. infusion, both verapamil and norverapamil tissue: plasma concentration ratios were greater than after i.p. administration. Higher tissue: plasma verapamil concentration ratios after i.v. administration than after i.p. administration suggest either only a pseudoequilibrium is attained after i.p. administration or that determinants of tissue distribution of racemic verapamil differ with different routes of drug administration. In these studies, MAP provided a reasonable pharmacodynamic marker for verapamil tissue and plasma concentrations.  相似文献   
29.
Background/aims: The objective and quantitative assessment of the skin is important in medical and cosmeceutical research. Assessment of color is an important element for analyzing the surface of the skin, which is usually determined subjectively by a doctor or using color analysis devices. These devices, however, cannot provide correct color information because color is construed from the mean value of the observation region, and analysis of color distribution is impossible. The purpose of this paper is to develop an objective analysis method to permit skin color measurement of each pixel unit of an image and analyze the distribution of skin surface color. Methods: The Skin Color Distribution Analyzer (SCDA) is an analysis method newly developed at the Research Institute for Skin Image at Korea University. The SCDA system presented in this paper performed a novel form of quantitative and objective analysis of skin color distribution using each pixel color model parameter found in image wavelength information. In this paper, distribution analysis was conducted on normal skin and skin lesions and skin affected by artificially induced irritant contact dermatitis and pigmented nevous. The method selected a grade using a color model parameter. Twenty healthy Korean males participated in this study. A comparative study of the eight anatomical areas was performed, including the exposure and non‐exposure parts and the medial aspect and the lateral aspect of the forearm. A reliability test for the SCDA system was also conducted with a spectrometer (SPEC) using the color analysis method. Results: Each skin lesion was precisely segmented by grade and each parameter hada different statistical significance for results of analysis of distribution in pigmented nevous and the artificially induced irritant contact dermatitis. Parameters L*, b*, a*, and EI showed salient traits. Showed resemble measured result in the SCDA system and the SPEC of normal skin. The exposed site, in comparison with the non‐exposed site, showed a notable difference in the L* parameter and a significant statistical difference in the x and z parameters, except b*. The comparison of the medial and lateral aspects of the forearm showed a notable difference in the L* parameter and a significant statistical difference in the parameters except y and b*. In the reliability test result using the SCDA system and the SPEC, the SCDA system was highly reliabile in terms of the CV value in all color model parameters. Conclusions: The color distribution analysis method using the SCDA system has revealed an aspect that the existent method of medical research has not shown, and is considered to be more reliable than other methods. This method can provide better study findings because it can be applied to other fields in addition to the medical science field and the ripple effect is thought to be bigger in other science field too.  相似文献   
30.
目的探索体外构建组织工程血管及细胞种植的方法。方法(1)制备管状支架模具,采用模具成形,冷冻干燥等技术,应用胶原和透明质酸复合体外预构管状支架;(2)分动态种植和静态培养两组进行细胞分层种植,每组12个,应用水溶性磺酸四唑(WST-1)测定,扫描电镜观察,5-溴2-脱氧嘧啶核苷(BrdU)细胞标记鉴定比较两种方法的细胞生长情况。结果(1)成功制备了管状支架,在培养液中约3周可保持管腔形态不变形,不塌陷;2.WST-1测定值在培养6、14、20 d分别为:动态组0.842±0.110、1.124±0.102、1.132±0.112,静态组0.386±0.121、0.489±0.245、0.499±0.265,两组比较差异有统计学意义,电镜和BrdU标记表明动态组细胞排列整齐有序。结论应用模具成形,冷冻干燥技术预构管状支架的方法切实可行,动态培养有助于细胞种植,本研究为组织工程血管的构建方法提供了思路。  相似文献   
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