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121.
To identify differentially expressed genes between obese individuals and normal control, we have undertaken suppression subtractive hybridization (SSH). Omental adipose tissues were obtained via abdominal surgery for appendicitis in both 13 obese subjects[BMI (body mass index) 〉 30 kg/m(2)] and 13 normal subjects (BMI 〉 18 and 〈 25 kg/m(2)).  相似文献   
122.
Attempts have been made to culture the mucosa from various parts of the gastrointestinal tract. In this study, using an explant culture method, epithelial cells have been successfully cultured from all major regions of the gastrointestinal tract. The success rate, as judged by outgrowth of epithelial cells for at least 4 weeks, varied with the tissue studied with 19/50 colonic biopsies, 5/11 small intestinal biopsies, 9/12 stomach biopsies and 42/47 gallbladder biopsies yielding outgrowth of epithelial cells. Differentiation of the epithelial cells along the mucus cell pathway could be demonstrated on the monolayer cultures using Periodic acid Schiff or Alcian blue staining. Because the cultures were very heterogeneous and many morphological cell types were present in most cultures, differentiation along the other known differentiation pathways of the gastrointestinal mucosa, such as development of absorptive cells and endocrine cells, could not be excluded.
The problem of bacterial contamination, which has hindered previous studies on tissue from these sites, was overcome by decontaminating the biopsy by soaking in dilute sodium hypochlorite (0.04%).  相似文献   
123.
目的探索急性重症肝炎患者发生肝性脑病的危险因素,以便进行早期干预。方法收集血浆凝血酶原时间(PT)延长,活动度〈40%的急性重症肝炎患者69例,对69例患者的年龄、性别和基础疾病等临床背景资料和总胆红素、直接胆红素、谷草转氨酶(AST)、谷丙转氨酶(ALT)、血浆白蛋白、胆碱脂酶、血浆凝血酶原时间(PT)、白细胞计数(WBC)、血小板计数(Plt)等实验室检查数据进行单因素分析和多元Logistic回归分析。结果单因素分析和多元Logistic回归分析均提示年龄、血胆红素水平和血浆凝血酶原时间在肝性脑病组和非肝性脑病组之间有统计学差异。结论约30%的急性重症肝炎患者发展成为肝性脑病。高龄、血浆凝血酶原时间延长、活动度下降、高血浆总胆红素等是急性重症肝炎患者发展成为肝性脑病的潜在危险因素。  相似文献   
124.
肝囊肿腹腔镜开窗引流术后复发原因的探讨   总被引:8,自引:2,他引:6  
目的探讨肝囊肿腹腔镜开窗引流术后复发的原因. 方法回顾性总结1998年6月~2003年8月54例肝囊肿腹腔镜下开窗引流术的临床资料. 结果 52例随访1~6年,5例复发,复发率9.6%(5/52).3例由于囊肿位置特殊开窗过小,1例由于多发囊肿之间的透明隔未予切开,1例系多囊肝术后复发. 结论适应证选择不当、囊肿开窗过小、遗漏多发囊肿以及黏膜处理不当是导致复发的主要原因.  相似文献   
125.
目的 研究pcDU6载体质粒介导的转化生长因子β1(TGF-β1)短发夹RNA(shRNA)对人血清白蛋白(HSA)致人肾近曲小管上皮细胞(HK2细胞)增殖,TGF-β1、结缔组织生长因子(CTGF)和纤连蛋白(FN)表达的影响,并探讨有关机制。方法 构建TGF-β1shRNA的pcDU6载体质粒,体外培养HK2细胞株。采用脂质体转染将表达TGF-β1shRNA的pcDU6质粒载体(pcDU6-A1-A2和peDU6-B1-B2)分别导人实验组细胞。用HSA(5g/L)刺激HK2细胞12h或24h。四甲基偶氮唑盐(MTF)比色法测定细胞增殖水平。RT-PCR半定量分析HK2细胞中TGF-β1、CTGF和FNmRNA的表达水平;双抗夹心酶联免疫吸附法检测HK2细胞培养液中TGF-β1及FN蛋白质水平。结果 HK2细胞在HSA刺激下,其TGF-β1、CTGF及FNmRNA的表达明显上调,培养液中TGF-β1和FN的蛋白质含量亦明显升高(P〈0.05)。与pcDU6空载体组比较,pcDU6载体质粒介导的TGF-β1shRNA干扰组TGF-β1、CTGF及FNmRNA的表达明显下调(P〈0.05)。TGF-β1shRNA转染HK2细胞后12h或24h,细胞培养液中TGF-β1和FN蛋白质含量明显下降,HK2细胞增殖被部分抑制(P〈0.05)。在细胞增殖、TGF-β1、CTGF及FN基因表达方面,TGF-β1shRNA干扰组组间比较,以及pcDU6空载体转染组与HSA刺激组比较,差异均无统计学意义。结论 peDU6载体质粒介导的TGF-β1shRNA能够明显抑制HSA刺激下HK2细胞增殖、TGF-β1、CTGF和FN基因的表达。HSA刺激HK2细胞增殖及CTGF和FN基因的过表达可能通过TGF-β1介导。  相似文献   
126.
[目的]观察人骨髓间充质干细胞在速固化磷酸钙骨水泥支架中的增殖和生长情况。[方法]将速固化壳聚糖-磷酸钙骨水泥支架材料预先成形。采用全骨髓法分离人骨髓间充质细胞并在体外对细胞进行培养和扩增。72h首次换液,细胞融合80%传代,取第3代细胞用于实验。将细胞与磷酸钙骨水泥支架复合培养,分别利用四甲基偶氮唑蓝MTT法及扫描电镜等检测细胞在材料中的增殖和生长情况。[结果]用酶标仪检测OD值提示共培养后,支架内的细胞数量逐渐增加。扫描电镜结果显示支架材料内部为多孔结构,孔内见有细胞生长,细胞表面可见分泌颗粒。[结论]速固化壳聚糖-磷酸钙骨水泥对人骨髓间充质干细胞有较好的细胞相容性,细胞可在材料内黏附和增殖,是理想的骨组织工程支架材料。  相似文献   
127.
A portion of transplanted islets is lost during engraftment as a result of stressful events, involving hypoxia and production of proinflammatory molecules by islets. Two of these molecules (monocyte chemoattractant protein-1, CCL2/MCP-1 and tissue factor, TF) are directly correlated with reduced graft function. We evaluated which factors reduce islet proinflammatory conditions. In particular the effects of different culture media supplemented with proteins or antioxidant agents on CCL2/MCP-1 and TF human islet release were evaluated. We observed that human islets after culture in final wash culture medium (FW) significantly decreased CCL2/MCP-1 release and TF production compared with CMRL and M199. These effects were independent from the type of protein added to the media (human serum, human albumin, fetal calf serum). Glutathione in FW further decreased CCL2/MCP-1 in a dose-dependent manner. Culture conditions can modulate the proinflammatory state of islets, and could be used in clinical islet transplantation to reduce inflammation during engraftment.  相似文献   
128.
目的介绍一种较新的矫治鹰钩鼻鼻尖畸形的手术方法。方法自1995年2月至2005年5月,采用埋没导引缝合技术对18例鹰钩鼻鼻尖畸形患者进行手术矫治,术后结合鼻管支撑的鼻孔悬吊法外固定7~10d。结果术后经14个月至3年的随访,18例患者的鼻尖外形良好,形态满意。其中1例患者因鼻腔内悬吊线穿透引起轻度炎症,术后3周剪除缝线,5d自愈。结论采用埋没导引缝合的手术方法对鹰钩鼻鼻尖畸形患者进行矫治,并结合缝合、悬吊和固定,获得了良好的术后效果。此方法是一种较理想的手术方法,值得推广应用。  相似文献   
129.
《Pediatric Dental Journal》2006,16(2):132-137
We report the newly developed Micro-CT, which allows us to observe the individual animal over a long experimental period and to compare changes in pulp tissue in relation to growth and aging without considering individual differences. Further, we used pathological examination to prove similar the result observing from Micro-CT. We have examined wound healing of teeth after pulpotomy in rats, and could clearly observe histopathological changes in the affected teeth and the absorption of temporary filling material and pulp capping agents. In cases with breakage of the dental crown, the CT images agreed with the pathological observations, and it was possible to estimate the time of breakage. In vivo Micro-CT is possible to apply in continuous recording of small experimental animals, such as rats, under anesthesia and the result is sufficiently high. High-quality image was obtained in of the entire head region of the rat. It was suggested that this method can be used for long-term continuous observation of changes in the teeth conditions after pulpotomy in experimental animals. We report the newly developed Micro-CT, which allows us to observe the individual animal over a long experimental period and to compare changes in pulp tissue in relation to growth and aging without considering individual differences.  相似文献   
130.
Summary Primary presentation of an intradural Non-Hodgkin’s lymphoma is rare. Recently these B cell lymphomas of mucosa associated lymphoid tissue (MALT) have gained acceptance as an important pathological subtype and are distinguishable from other primary CNS lymphomas that exhibit aggressive behaviour. Over the past decade a number of these lesions have been reported to resemble a meningioma both intra-operatively and radiologically. The authors outline such a case of marginal zone B cell lymphoma that clinically and radiologically resembled a meningioma. This case illustrates the rare occurrence of low grade dural B cell lymphoma and the need to consider this entity in the differential diagnosis of CNS lesions, if appropriate targeted therapy is to be administered.  相似文献   
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