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31.
Conventional angiography is considered to be gold standard for evaluating the degree of carotid artery stenosis. However, this technique carries a risk of complications. Thus, noninvasive techniques have been developed to avoid conventional angiography. Among these techniques, duplex sonography certainly constitutes the most attractive method, providing both morphological and hemodynamic data by combining different acquisition modalities. Contrast-enhanced MR angiography (MRA) is a recent development providing information on the intracranial and cervical vascularization in a short acquisition time. Previous studies have showed the reliability of this technique to detect severe carotid stenosis. Helicoidal CT is a third noninvasive method providing a reliable evaluation of carotid artery stenosis by analyzing both the axial CT images and the 3D reconstruction. However, CT angiography requires a radiation does and injection of an iodinated contrast agent. Moreover, the surrounding venous and bone structures may obscure evaluation of the arterial lumen.  相似文献   
32.
Summary Varus deformity of the knee is common in young children who have suffered from fulminating purpura. This study was directed at the anatomic features of the vascularisation of the upper end of the tibia that might account for such deformation. It was based on the dissection of 28 anatomic specimens prepared by injection of Indian ink into the vascular trunk. 16 specimens were diaphanised for better analysis of the intracartilaginous distribution of the vessels. The study showed that the vascularisation of the medial condyle of the tibia is poor and of terminal nature, which may explain the occurrence of ischemic growth disorders following fulminating purpura.
Etude de la vascularisation artérielle du condyle médial du tibia chez le foetus
Résumé Les déformations en varus du genou chez les jeunes enfants ayant présenté un purpura fulminans sont fréquentes. Ce travail a pour objet de rechercher les caractéristiques anatomiques de la vascularisation de l'extrémité supérieure du tibia qui peuvent expliquer ces déformations. L'étude porte sur la dissection de 28 pièces anatomiques préparées par injection de l'axe vasculaire à l'encre de Chine. Pour mieux analyser la répartition intra-cartilagineuse des vaisseaux, 16 pièces ont été diaphanisées. Cette étude montre que la vascularisation du condyle médial du tibia est pauvre, de type terminal, ce qui peut expliquer la survenue de troubles de croissance ischémiques dans les suites d'un purpura fulminans.
  相似文献   
33.
Expression of cadherins and CD44 isoforms in ovarian endometrial cysts   总被引:3,自引:0,他引:3  
We evaluated the immunohistochemical expression of cadherins and CD44 variants in 20 endometriomas, 20 cystadenomas, 20 borderline ovarian tumours as well as 20 ovarian carcinomas, and the serological and cystic fluid concentrations of soluble E-cadherin and soluble CD44 standard (sCD44sdt) in 20 endometriomas, 20 cystadenomas, six borderline and 11 carcinomas of the ovary. In endometriomas, immunostaining of E- and N-cadherin was negative (20 and 30% respectively). CD44 H, v3 and v6 immunostaining were detected in 63, 10 and 40% respectively. A difference in immunostaining for E-cadherin was found between endometriomas and cystadenomas (P < 0.001) and for N- cadherin between endometriomas and carcinomas (P < 0.001). A difference in CD44H immunostaining was observed between endometriomas and cystadenomas (P < 0.035) but not with borderline ovarian tumours and carcinomas. No difference in serum concentrations of soluble E- cadherins and CD44 standard was found between the four groups of tumours. Cystic fluid concentrations of E-cadherin were lower in endometriomas than in borderline tumours and ovarian carcinomas (P < 0.001). High concentrations of soluble CD44 standard cystic fluid were found in endometriomas than in other ovarian cysts. Endometriomas and borderline tumours share alterations of cadherins and CD44 isoforms which may help in the understanding of the aggressive and invasive potentials of endometriotic cells.   相似文献   
34.
Urea rebound and delivered Kt/V determination with a continuous urea sensor   总被引:2,自引:1,他引:2  
BACKGROUND: The recent introduction of urea sensors for dialysis monitoring has made possible new approaches to urea kinetic modelling. In this study we show how the equilibrated postdialysis urea concentration (Ceq) and Kt/V corrected for double-pool urea kinetics (Kt/Vdp) can be accurately determined using an on-line sensor providing a continuous measure of blood water urea. A modification of the Smye constant volume double-pool theory led to the following equations for Ceq and Kt/Vdp [formula: see text] where Cpre is the blood concentration measured at the start of dialysis, t is the length of the dialysis session (in min) and S(ex) is the constant slope of the blood urea logarithm concentration decline following development of the intercompartmental urea concentration gradient in the first 30-60 min of dialysis. METHODS: These equations were tested in 11 patients undergoing 165-240 min of paired filtration dialysis with continuous monitoring of blood urea concentration. Cpre was determined as the plateau concentration during a preliminary period of 15-20 min of slow isolated ultrafiltration. S(ex) was accurately determined from linear regression applied to the urea sensor data from the 80-min point to the end of dialysis. RESULTS: Ceq and Kt/Vdp determined from the above equations compared closely to values determined from 25-40 min of urea rebound monitoring with the urea sensor: 10.6 +/- 3.0 versus 10.8 +/- 2.7 mmol/l (mean +/- SD) for Ceq and 1.21 +/- 0.24 versus 1.18 +/- 0.20 for Kt/Vdp, compared to single-pool values of Kt/V = 1.34 +/- 0.23. CONCLUSION: This technique may be readily programmed into on-line urea monitors to provide current and extrapolated values of Ceq and Kt/Vdp from about the first hour of dialysis.   相似文献   
35.
Epling-Burnette  PK; Wei  S; Blanchard  DK; Spranzi  E; Djeu  JY 《Blood》1993,81(11):3130-3137
Human monocytes express interleukin-2 receptor beta (IL-2R beta) constitutively; however, the function of these receptors has not been fully delineated. We discovered that IL-2R beta directs two biologic activities in human monocytes, the release of granulocyte-macrophage colony-stimulating factor (GM-CSF) and increased susceptibility to lysis by lymphokine-activated killer cells (LAK) cells. Human monocytes were purified from peripheral blood mononuclear cells by plastic adherence and anti-CD2 plus complement lysis. By a 5-hour 51Cr-release assay, monocytes cultured in IL-2 were found to gain increasing susceptibility to LAK cells with time and this effect was dose dependent. Maximal susceptibility was obtained with a 4-day culture in 1,000 U/mL of IL-2. Monocytes were also found to release GM-CSF in response to IL-2 using a CSF-dependent cell line, Mo7e. Because IL-2- induced GM-CSF release coincides with LAK lysis of IL-2-cultured monocytes, we treated monocytes with anti-GM-CSF and anti-IL-2R beta to determine whether GM-CSF release and LAK susceptibility were dependent or independent events. We found that both phenomena were inhibited by either antibody. Therefore, we conclude that IL-2-induced release of GM- CSF is mediated by IL-2R beta, which then acts to modulate the susceptibility of monocytes to lysis by LAK cells.  相似文献   
36.
阿魏酸钠对花生四烯酸代谢的影响   总被引:10,自引:0,他引:10  
利用放射薄层方法测定兔血小板花生四烯酸代谢产物TXB2,PGE2和PGF。用放射免疫法测定兔血小板TXB2及主动脉6-keto-PGF。阿魏酸钠(SF,0.1~3.2 mmol/L),抑制14C-花生四烯酸转化为TXB2,呈剂量效应关系,IC50为0.762 mmol/L。SF在较高浓度(0.8~3.2mmol/L)时亦抑制PGE2,PGF的生成。用放免法观察到,SF对血小板TXB2和动脉壁6-keto-PGF的生成均有抑制作用,对TXB2的作用较强。结果提示,SF可抑制兔血小板和动脉壁环氧酶活性。  相似文献   
37.
BACKGROUND: Quality of life (QOL) assessment has emerged to measure and quantify the balance between treatment benefit and toxicity, and has a value in predicting response and overall survival in cancer patients. METHODS: From July 1995 to February 1997, 38 symptomatic patients with advanced non-small cell lung cancer (NSCLC) were treated with MIP chemotherapy (mitomycin 6 mg/m2, ifosfamide 3000 mg/m2 and cisplatin 50 mg/m2 on day 1 every 3 weeks). Patients were assessed for QOL including physical well-being, general symptoms and lung cancer-specific symptoms, as well as objective response. RESULTS: The overall response rate was 38.9% (14/36, all were partial response) and the median duration of response was 3.5 months [95% confidence interval (CI) 2.0-4.0]. The median duration of overall survival was 7 months (95% CI 5.9-8.5). The overall improvement of QOL was 58.3% with 21 patients feeling better on treatment. The toxicity of chemotherapy was mild, mainly nausea/vomiting and minimal alopecia. Using multiple clinical predictors of survival (age, histology, stage, performance status), only change of QOL emerged significantly (P = 0.0007). CONCLUSIONS: MIP had an endurable response and low toxicity profile, and provided good QOL. Integral QOL data in our study provided the strong prediction of survival in advanced NSCLC. Further experienced QOL study will provide greatly enhanced outcome data in clinical trials.   相似文献   
38.
亲属活体肾移植18例报告   总被引:2,自引:2,他引:2  
目的:总结亲属活体肾移植的临床经验,以期提高该技术的安全性及疗效。方法:选择2005—11/2006—12解放军第一七五医院收治的亲属活体肾移植患者18例,均知情同意。受体均为慢性肾小球肾炎;供体年龄24-74岁,17例有血缘关系,另一例为妻子供肾。均行经腰开放手术取肾,左侧供肾15例,右侧供肾3例。术后受体采用环孢素A+霉酚酸酯+激素三联低剂量免疫抑制剂方案。结果:①所有供体在术后10d左右出院,均无严重并发症且肾功能正常。②16例受体均在术后1-3d内移植肾功能恢复正常,另2例因供肾迷走血管损伤在术后5d左右血肌酐下降到200μmol/L,1个月左右稳定在160μmol/L。1例他克莫司仅服0.5-0.75mg/d,于术后5个月出现急性排斥反应。1例术后2个月出现环孢素A急性肾毒性(血药浓度谷值为343μg,L)。2例出现药物性肝炎。结论:亲属活体肾移植术较为安全,排斥反应少,结果满意。免疫抑制剂宜采用低剂量方案。  相似文献   
39.
不同孔径纳米羟基磷灰石人工骨修复兔桡骨缺损效果比较   总被引:4,自引:7,他引:4  
目的:纳米级的羟基磷灰石材料与人体内组织成分更为相似,具有更佳的生物性能。评价不同孔径的多孔纳米羟基磷灰石人工骨的骨缺损修复能力,从而筛选出适合的孔径以达到骨传导功能与生物力学性能的良好统一。方法:实验于2005-10/2006-10在深圳市第二人民医院中心实验室完成。①实验材料:纳米羟基磷灰石人工骨以硝酸钙和磷酸二氢铵为原料,采用溶胶-絮凝法制备粉体,运用压力成型、木模成型和浸渍成型分别制得孔隙分布均匀的孔径分别为50~150μm、100~250μm和300~500μm的多孔纳米羟基磷灰石人工骨。②实验动物:雄性新西兰大白兔60只随机分为植入50~150μm孔径材料组、植入100~250μm孔径材料组、植入300~500μm孔径材料组、空白对照组,每组15只。实验过程中对动物处置符合动物伦理学要求。③实验方法:制备双侧桡骨骨缺损动物模型,然后用3种不同孔径的纳米羟基磷灰石人工骨材料植入骨缺损处进行修复,空白对照组不植入任何材料。④实验评估:术后4,8和12周分别行大体标本观察、X射线片观察、扫描电镜观察及生物力学测试,比较各组材料修复骨缺损的能力。结果:实验动物均进入结果分析。①X射线片检查结果:术后4周、8周、12周,植入100~250μm孔径材料组X射线评分高于植入50~150μm,300~500μm孔径材料组,差异有显著性意义(P<0.05)。②生物力学检测结果:术后4周、8周、12周,植入100~250μm孔径材料组生物力学强度高于植入50~150μm,300~500μm孔径材料组,差异有显著性意义(P<0.05)。③扫描电镜观察结果:植入100~250μm孔径材料组成骨效果明显优于植入50~150μm,300~500μm孔径材料组和空白对照组。结论:纳米羟基磷灰石人工骨具有良好的成骨能力,但其骨修复能力受孔径因素的影响,孔径100~250μm的纳米羟基磷灰石人工骨材料成骨能力较好。  相似文献   
40.
目的:应用异硫氰酸荧光素标记天花粉蛋白,在激光共聚焦显微镜下直接观察天花粉蛋白进入黑色素瘤B16细胞的动态过程并分析其对黑色瘤B16细胞的损伤作用。方法:实验于2003-08/2004-08在南通大学神经再生重点实验室完成。将常规传代培养的黑色素瘤B16细胞用胰酶消化,以5×109个/L的浓度种植于24孔培养板。将天花粉蛋白、异硫氰酸荧光素-天花粉蛋白、异硫氰酸荧光素-牛血清白蛋白分别加入培养细胞中,终浓度为50mg/L,同时加入等量生理盐水作为正常对照组,每组再分别设3,6,12h不同孵育时间组。异硫氰酸荧光素标记天花粉蛋白后,利用激光共聚焦显微镜观察异硫氰酸荧光素-天花粉蛋白进入细胞的过程及其荧光强度,CCK-8细胞毒性实验评估各组细胞存活率、并用单细胞凝胶电泳及hoechst33258染核观察天花粉蛋白对黑色素瘤B16细胞致DNA损伤作用。结果:①终浓度50mg/L的异硫氰酸荧光素-天花粉蛋白孵育3h时已经进入黑色素瘤细胞,6h时进入细胞量达到最高,12h时已轻度下降,各时间点比较差异有统计学意义(P<0.01)。异硫氰酸荧光素-天花粉蛋白组与异硫氰酸荧光素-牛血清白蛋白组荧光强度差异有显著性(P<0.01)。②终浓度50mg/L异硫氰酸荧光素-天花粉蛋白、天花粉蛋白孵育黑色素瘤细胞3,6h后利用单细胞电泳和Hoechst33258染色未观察到核形态的变化;但孵育6h后CCK-8细胞毒性实验显示活细胞数量明显下降;孵育12h后出现DNA损伤的特征性彗星尾现象,并观察到明显的核浓缩和边集现象,出现特征性凋亡小体。结论:孵育6h时天花粉蛋白进入细胞量最多,但并没有明显的细胞DNA损伤的作用,而孵育12h时产生明显的细胞毒作用和凋亡的发生。  相似文献   
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