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101.
脱细胞尿道及其海绵体基质制备的实验研究   总被引:1,自引:0,他引:1  
目的 探索脱细胞尿道及其海绵体基质的制备方法。方法取健康壮年兔完整尿道及其海绵体组织,以Triton-X100与NH3H2O联合提取法进行脱细胞处理。标本做HE染色,组织学观察分析脱细胞效果。结果脱细胞处理11天后,成功获得脱细胞及其海绵体基质,所得基质外观良好。HE染色观察无细胞存在。弹力纤维排列规整,间隙较大,结构无破坏。结论利用Triton-X100与NH3H2O联合提取法可成功制备完整无细胞尿道及其海绵体基质,为尿道再造修复提供崭新思路。  相似文献   
102.
The morphologic effects of androgen deprivation in the different lobes of the rat prostate were examined by light microscopic morphometry. The prostates of Wistar male rats (260-340 g) were fixed in situ by glutaraldehyde perfusion in castrated animals 1 week after gonadectomy and in intact animals. The ventral (VP), dorsal (DP), and lateral (LP) lobes as well as the coagulating gland (CG) were dissected out, weighed, and processed for light microscopy. Using stereologic methods the following parameters were estimated for each lobe: volume fraction of connective tissue, epithelium and glandular lumina, average epithelial height, average epithelial cell volume, and total number of epithelial cells. Castration leads to a 58-76% reduction of the wet weight of all prostatic lobes. The decrease of glandular tissue is greater in VP than in LP, DP, and CG. In VP and LP, there is a 39-45% reduction of the epithelial height, and this effect is less pronounced in DP and CG. For all lobes, the shrinkage of average epithelial cell volume is in the same range (25-30%). Moreover, in VP and LP, there is a 70% reduction of the total number of cells, whereas the reduction is less in DP and CG. It thus seems that the reduction of prostatic epithelial tissue mass upon castration is due to a reduction of the number of cells as well as a reduction of the volume of individual cells. VP and LP appear to be more androgen-dependent than DP and CG.  相似文献   
103.
Apolipoprotein E is synthesized and secreted by degenerating peripheral nerve, but the role of resident endoneurial cells in this process is not clear. To exclude the involvement of nonresident cells, we examined the cellular source of endoneurial apolipoprotein E in explant cultures of rat sciatic nerve. The cellular outgrowth from these explant cultures released apolipoprotein E into the culture medium. The cellular outgrowth contained fibroblasts, Schwann cells, and a population of cells with many phenotypic characteristics of macrophages, including the production of apolipoprotein E. No other cell type in the cultures appeared to contribute to this production. These data suggest that apolipoprotein E is produced by resident endoneurial cells in explant cultures and that these cells are macrophages.  相似文献   
104.
The purpose of this study was to examine the long-term clinical results of meniscus transplantation for articular cartilage defects in the knee joint. The type of study was case series. From October 1990 to June 1995, eight cases underwent allogenic or autogenic meniscus transplantations for articular cartilage defects, and seven cases were available for follow-up evaluations. The age at surgery ranged from 14 to 42 years of age (average 22.5). In one case, transplantation of tissue-engineered cartilage was performed due to pain 5 years after surgery. The other six cases were followed up for 8–13 years (average 10.1). The size of the cartilage defect ranged from 1.0 to 6.3 cm2 (average 2.8 cm2). Patients were evaluated with the Lysholm score and MR images. We also performed arthroscopic examinations in three cases at the final evaluation. This study leads to the conclusion that meniscus transplantation for articular cartilage damage is not comparable to autologous chondrocyte transplantation. Two cases showed a good clinical outcome but the tissue remained as fibrocartilage tissue in the long-term.  相似文献   
105.
T可以减少超重高甘油三酯血症患者体脂肪,降低血甘油三酯和低密度脂蛋白胆固醇水平.  相似文献   
106.
目的研究鼠婴肾组织移植于肾包膜下对促红细胞生成素的调节作用,为临床应用治疗肾性贫血提供理论依据。方法以Wistar雄性大鼠建立慢性肾功能衰竭动物模型为受体,将鼠婴肾组织块多点植入受体肾包膜下。治疗期间用EPO酶联免疫(ELISA)试剂盒测定血清EPO水平;观察肾组织病理改变,用免疫组化方法检测EPO在移植物中的表达。结果①60d时D组血清促红细胞生成素(1.768±0.140)mu/mL高于B组(1.160±0.324)mu/mL(P<0.01),与C组(2.329±0.125)mu/mL也有差异(P<0.05)。②移植后60d,移植物的体积由1mm3增至3-4mm3大小,表面血管网丰富,光镜下见肾小球、肾小管结构正常;③移植物EPO免疫组化,发现移植物EPO着色颗粒主要分布于肾皮质的肾小管,明显多于病例对照组大鼠肾组织(P<0.05)。结论通过对移植物的形态观察和功能测定,证明肾组织移植是一种有效的治疗手段,有可能为慢性肾性贫血提供一种新的途径。  相似文献   
107.
老化皮肤的胶原与弹性组织变化研究   总被引:3,自引:2,他引:1  
石钰  李利  王曦 《中国美容医学》2007,16(6):727-730
目的:探讨光曝露情况及年龄因素对皮肤中弹性组织、Ⅰ/Ⅲ型胶原及基底膜Ⅳ型胶原的影响,进而探索皱纹形成的组织学原因。方法:对80例取自不同年龄志愿者的曝光部位(眶周/前额、面颊)及非曝光部位(腹部/臀部)的皮肤组织进行HE染色、Weigert染色、苦味酸天狼猩红染色及免疫组化处理,采用显微形态观察和半定量分析。结果:各部位皮肤基底膜内Ⅳ型胶原的含量无差异;随着曝光时间增加,前额/眶周皮肤中Ⅰ型胶原减少率最大,弹性变性物质增加率最大。结论:前额/眶周皮肤的胶原显著减少和弹性变性物质明显增生,是该部位皮肤皱纹早发的重要原因。  相似文献   
108.
A rare case of an infected chronic hematoma in a patient with immunodeficiency syndrome mimicking a soft tissue neoplasm is presented. There are few reported cases of hematogenous infection of chronic hematomas, which be difficult to differentiate from soft tissue neoplasms.  相似文献   
109.
The aim of this study was to fabricate an artificial bile duct for the development of a new treatment for biliary diseases. Eighteen hybrid pigs were implanted with a bile duct organoid unit (BDOU) made of a bioabsorbable polymer. Twelve of the transplanted BDOUs had been seeded with autologous bone marrow cells (BMCs) in advance. Six animals, the controls, were grafted with the scaffold alone with no BMCs seeded. The common bile duct was cut, the hepatic cut end of the native common bile duct was anastomosed to the BDOU and the other end was anastomosed to the duodenum. The controls underwent a similar operation. The neo-bile duct was removed at pre-determined time points and investigated histologically. All 18 recipient pigs survived until their sacrifice at 6 weeks, 10 weeks or 6 months. Histological examination revealed incomplete epithelialization of the neo-bile duct at 6 weeks and 10 weeks after transplantation. At 6 months, the organoid exhibited a morphology almost identical to that of the native common bile duct. No differences were found between the controls and BMC-seeded pigs. These results show that the artificial bile duct thus fabricated can serve as a substitute for the native bile duct.  相似文献   
110.
目的:探讨成年男性舌根部舌下神经解剖走行特点,指导临床舌根部射频温控减容术治疗阻塞性睡眠呼吸暂停低通气综合征(OSAHS)时针形电极刺入舌根部的部位及深度,以避免损伤舌下神经。方法:选择10具成年男性的舌标本,定型后在冰冻状态下作冠状切面,通过计算机图像处理与测量系统行舌下神经定位测量,并进行相关的统计学分析。结果:(1)两侧舌下神经呈对称性分布。(2)成年男性舌下神经舌内部分的主干(本实验为舌盲孔前后15mm范围内)其垂直向解剖走行基本恒定,距舌表面(22.21±2.22)mm;水平向走行中,舌盲孔后一般位于舌中内(近中线侧)(28.61±2.66)%处,舌肓孔前为(21.89±1.93)%处。结论:本实验为舌根部射频温控减容术治疗OSAHS提供了一个相对安全的范围:在不超过(22.21±2.22)mm深度且舌盲孔后避开中内(近中线侧)(28.61±2.66)%区域、舌盲孔前避开中(内近中线侧)(21.89±1.93)%区域,基本不会损伤舌下神经。  相似文献   
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