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81.
下腹部多个真皮下血管网皮瓣在手外伤修复中的应用   总被引:10,自引:3,他引:7  
目的:应用下腹部多个真皮下血管网皮瓣修复手外伤,方法:在下腹形成以旋髂浅血管为蒂的髂腰部皮瓣及以腹壁浅血管为蒂的下腹部皮瓣,二皮瓣共蒂形成双叶皮瓣,同时将其修薄,形成有轴心血管的真皮下血管网皮瓣,修复两指完全脱套伤。在下腹部形成多个真皮下血管网的任意皮瓣,修复多个指背皮肤缺损伴有肌腱及骨外露的创面。供区如不能直接拉拢缝合,可取断层皮片修复供区创面.结果:本组10例中,8例采用下腹部双叶真皮下血管网轴型皮瓣修复,2例采用下腹部真皮下血管网任意皮瓣修复,术后效果。结论:采用多个真皮下血管网皮瓣修复手外伤的创面,伤指不需并指,去脂,分指,术后外形佳,是目前较理想的修复手外伤的手术方法。  相似文献   
82.
作者采用PCR方法克隆了我国海南省FCC1/HN株P190抗原两个保守区基因,分别定名为P190CRI和P190CRV。基因片段经纯化后连接到pUC18载体中进行DNA序列分析,结果显示:除了P190CRV中有5个碱基变换外,其余序列均与MAD20型序列一致。经序列分析的两个基因片段分别与pGEX-2T载体连接,经双酶切鉴定后转化感受态JM109(DE_3)大肠杆菌进行高效融合表达,并且用Sepharose 4B-谷胱甘肽层析柱进行亲和纯化,结果为:两个插入基因片段均得到高效融合表达,经一步亲和纯化后就取得高纯度的重组蛋白。  相似文献   
83.
ABSTRACT: Short-chain fatty acids, such as butyrate and propionate, induce fetal globin gene expression and are under clinical investigation in the β-hemoglobinopathies. Limitations of the short-chain fatty acids as therapeutics include their rapid metabolism and a tendency to induce cell growth arrest if administered for prolonged periods. In studies described here, the cellular effects of other inducers of fetal globin, phenoxyacetic acid and derivatives of short-chain fatty acids and cinnamic acids, were investigated in the human erythroid cell line K562, the IL-3 dependent multi-lineage cell line (32D), and in mice and primates. Several test compounds supported 32D cell proliferation despite a 50-fold depletion of IL-3, which resulted in growth arrest and apoptotic death in control cells. The degree of proliferation induced by certain test compounds was similar to the degree of proliferation induced by Erythropoietin and G-CSF in the cells. Eight of ten compounds induced γ globin mRNA in K562 cells. A 2.5 to 6-fold increase in reticulocytosis was observedin vivoin mice treated with two prototype compounds. Pharmacokinetic studies of three prototype compounds demonstrated millimolar plasma concentrations after single oral doses for many hours in primates. These findings identify orally bioavailable compounds which induce γ globin gene expression and hematopoietic cell proliferation through an activity which partially abrogates requirements for IL-3. Such compounds provide potential for oral therapeutics which stimulate proliferation of hematopoietic cells of multiple lineages, as well as inducing fetal globin.  相似文献   
84.
应用不同浓度人白细胞干扰素处理10例慢性乙型肝炎病人外周血淋巴细胞,观察病人姐妹染色单体互换(SCE)频率的动力学变化.结果表明,人白细胞干扰素处理组SCE平均频率明显低于对照组,差异高度显著(P<0.01);慢性迁延性肝炎和慢性活动性肝炎处理组之间SCE平均频率无显著性差异;但人白细胞干扰素处理低浓度组SCE平均频率低于高浓度组,差异不显著(P>0.05).提示人白细胞干扰素具有诱导HBV损伤人体DNA的修复作用;大剂量人白细胞干扰素对HBV损伤人体DNA的修复未必有益.  相似文献   
85.
86.
The authors review the latest theories of peripheral nerve regeneration and repair. They present their research on nerve regeneration including the alterations in the mother cell body, and in the distal part of the axon, and the time required to reach the best production of amino acids for cytoskeleton reconstruction. Other research of particular interest which is presented regards the chemotactic arrangement of motor and sensory axons inside a vein. This research has shown that the axons are able to find their way to the appropriate (sensory or motor) distal endoneural tubes.Adoption phenomena are also presented.The discussion of surgery includes the type (suture, glueing, grafts, tubulization) and the time of surgical repair. Timing and repair strategies are related to the site of the lesion (which can require that a greater or smaller amount of cytoskeleton be reconstructed), the type of the injury, the state of surrounding tissues, the age of the patients, injuries to muscles, tendons, bones, vessels and skin. A scheme of strategy is proposed.  相似文献   
87.
Franklin  M.  Gonzalez  J.  Michaelson  R.  Glass  J.  Chock  D. 《Hernia》2002,6(4):171-174
Surgisis (Cook Surgical, Bloomington, Ind., USA) is a new four-ply bioactive, prosthetic mesh for hernia repair derived from porcine small-intestinal submucosa. It is a naturally occurring extracellular matrix which is easily absorbed, supports early and abundant new vessel growth, and serves as a template for the constructive remodeling of many tissues. As such, we believe that Surgisis mesh is ideal for use in contaminated or potentially contaminated fields in which ventral, incisional, or inguinal hernia repairs are required. From November 2000 through May 2002, 25 patients (11 male, 14 female) underwent placement of Surgisis mesh for a variety of different hernia repairs. A total of 25 hernia repairs were performed in our patient population. Fourteen procedures (56%) were performed in a potentially contaminated setting (i.e. with incarcerated/strangulated bowel within the hernia or coincident with a laparoscopic cholecystectomy/colectomy). Eleven repairs (44%) were performed in a grossly contaminated field, including one in which an infected polypropylene mesh from a previous inguinal hernia repair was replaced with Surgisis and one in which necrotic bowel was discovered within the hernial sac. Median follow-up was 15 months with a range of 1–20 months. Of the 25 total repairs, there was one wound infection complicated by enterocutaneous fistula in a patient originally operated on for ischemic bowel. The fistula was in a location independent of the Surgisis mesh. There were no mesh-related complications or recurrent hernias in our early postoperative follow-up period. Surgisis mesh appears to be a promising new prosthetic material for hernia repair, especially in contaminated or potentially contaminated fields. Obviously, long-term follow-up is still required. Electronic Publication  相似文献   
88.
Abstract Abstract. Various prosthetic materials have been proposed for the repair of abdominal wall defects. These materials offer tension-free repair and significantly lower recurrence rate. Their respective properties are related to such complications as seroma, infection, fistula formation, intestinal adhesions and removal. We compared the final outcome in treating abdominal wall defects in 56 patients with three different prosthetic materials: conventional polypropylene in a preperitoneal location, expanded polytetrafluoroethylene mesh, and hydrophilic membrane coated polyester mesh in an intraperitoneal location. The hydrophilic coated polyester group exhibited the lowest complication rate and the polypropylene group the highest. Electronic Publication  相似文献   
89.
Evidence from both experimental carcinogenesis and studies in human cirrhotic liver suggest that defective repair of the promutagenic DNA base lesion, O 6-methylguanine, is a factor in the multistep process of hepatocellular carcinogenesis. Ubiquitous environmental alkylating agents such as N-nitroso compounds can produce O 6-methylguanine in cellular DNA. Unrepaired, O 6-methylguanine can lead to the formation of G ? A transition mutations, a known mechanism of human oncogene activation and tumour suppressor gene inactivation. Combined treatment of rodents with an agent producing O 6-methylguanine in DNA, and an agent promoting cell proliferation, leads to development of hepatic nodules and hepatocellular carcinoma (HCC), cell division, hence DNA replication, being required for the propagation of tumorigenic mutation(s) in hepatocyte DNA. The paramount importance of O 6-methylguanine in hepatocellular carcinogenesis is indicated by the observation that transgenic mice engineered to have increased hepatic levels of repair enzyme O 6-methylguanine-DNA methyltransferase (MGMT) are significantly less prone to hepatocellular carcinogenesis following alkylating agent treatment. Cirrhosis is a universal risk factor for development of human HCC, and a condition that is characterized by increased hepatocyte proliferation as a result of tissue regeneration. Levels of the human repairing enzyme for O 6-methylguanine were found to be significantly lower in cirrhotic liver than in normal tissue. In accord with findings from animal models, this suggested a mechanism in which persistence of O 6-methylguanine due to defective DNA repair by MGMT, together with increased hepatocyte proliferation, might lead to specific gene mutation(s) and hepatocellular carcinogenesis. Screening for the presence and persistence of O 6-methylguanine in human DNA presently involves formidable technical difficulty. Indications are that such limitations might be overcome by the use of an ultrasensitive method such as immuno-polymerase chain reaction (PCR). This approach should allow parallel measurement of DNA adduct and repair enzyme in routine liver biopsy samples. It might also enable investigation of O 6-methylguanine in human genes specifically associated with hepatocellular carcinogenesis. Given the wide variation in human MGMT levels observed between individuals, tissues, and cells, this technology should be adapted to permit the ultrasensitive localisation and measurement of adducts and repairing enzyme in liver biopsy tissue sections. Ability to ultrasensitively measure O 6-methylguanine, and its repair enzyme, should prove valuable in the risk assessment of cirrhotic patients for developing hepatocellular carcinoma. Received for publication on July 6, 1998; accepted on Aug. 12, 1998  相似文献   
90.
Abstract: Accommodation refers to survival of a xenograft despite the presence of anti-donor organ antibodies and complement. We have recently shown that accommodation of a hamster heart transplanted to a rat receiving short-term cobra venom factor (CVF) and continuing cyclosporine A (CyA) therapy is associated with i) the expression in the endothelial cells (EC) and smooth muscle cells of the graft of a number of "protective" genes, ii) a prominent intragraft Th2 cytokine profile, and iii) the relatively heavy deposition of IgG2c antibodies on the EC of the graft. In contrast, rejecting grafts do not express the protective genes, have a Th1 cytokine profile, and apparently have lesser amounts of IgG2c. These findings are consistent with host factors (Th2 cytokines and IgG2c) contributing to xenograft accommodation. To test whether these host factors may predispose to the development of accommodation, we placed a second hamster heart into each of 12 rats carrying a surviving first heart; recipients were, at the time, receiving only CyA. Whereas first grafts transplanted to rats receiving only CyA survive for 3 to 4 days, 11 out of 12 second transplants survived more than 20 days, and the other survived for 7 days. Nine of the twelve were not rejected: of these, four were removed between day 35 and 132 for study, and the remainder are still beating at 35 to 52 days. The surviving second hearts we studied had accommodated in that the picture on immunopathology was the same as for surviving first hearts. We suggest that the Th2 cytokines and perhaps the IgG2c response are factors in allowing prolonged survival of the second grafts and, further, that these factors contribute to the expression in the EC and smooth muscle cells of the surviving second hearts of the protective genes.  相似文献   
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