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901.
腹腔镜辅助下大隐静脉隔绝术治疗大隐静脉曲张60例 总被引:1,自引:0,他引:1
目的探讨腹腔镜辅助下大隐静脉隔绝术的疗效。方法2000年1月~2004年1月对60例66条大隐静脉曲张腹腔镜辅助下行大隐静脉隔绝术,腹腔镜辅助下高位结扎、电灼大腿段大隐静脉,阻断其小腿段所有属支及交通支,使大隐静脉与体循环隔绝。结果手术时间30~60min,(50±9)min;术后住院时间3~5d,(3.5±0.6)d。60例随访1~36个月,平均28个月,无复发。结论腹腔镜辅助下大隐静脉隔绝术创伤小,疗效好,复发率低,是治疗大隐静脉曲张的理想术式。 相似文献
902.
目的通过动物实验观察不同骨水泥强化松质骨螺钉的生物力学和组织学变化动态,为骨质疏松骨折患者内固定提供理论基础。方法在10只杂种犬胫骨近端制作松质骨螺钉植入的动物模型,分别采用碳酸化羟基磷灰石水泥(CHC)和聚甲基丙烯酸甲酯(PMMA)强化,分别于术后5d、4、8、12和16周处死动物,观察螺钉拔出的生物力学和组织学变化。结果CHC强化的螺钉拔出力随手术后时间的延长而逐渐升高,16周时达到(512.5 14.5)N,而PMMA强化组螺钉拔出力则随手术后时间的延长而逐渐降低。CHC-骨界面结合紧密,并且随时间延长出现CHC降解和骨长入,而PMMA-骨界面形成一层纤维组织。结论CHC强化能够提高松质骨螺钉植入体内的稳定性,并且随植入时间延长而逐渐升高。 相似文献
903.
目的探讨腹膜后脓肿的病因,诊断和治疗。方法回顾性分析了1990-2004年诊断和治疗腹膜后脓肿33例的临床资料。结果急性坏死性胰腺炎后20例,胆囊切除胆总管探查术后4例,十二指肠损伤2例,阑尾穿孔3例,肾结石4例。超声检查确诊80%(20/25),CT检查确诊100%(22/22)。经腹部腹膜后脓肿切开置管引流25例,手术1~4次不等,后腰部切开引流8例。手术后并发应激性胃粘膜损伤致消化道出血7例,成人呼吸窘迫综合征(ARDS)5例,急性肾功能衰竭3例,死亡4例。治愈时间1~6个月,平均3.5个月。结论及时明确诊断,进行有效引流并加强营养支持是治疗成功的关键。 相似文献
904.
Takuro Yoshikawa Yasuyuki Suzuki Yasuhiro Fujino Keitaro Kakinoki Shiri Li Tadahiro Goto Tomohiro Tanaka Ippei Matsumoto Tetsuya Sakai Yasuki Tanioka Hiroshi Yokozaki Yoshikazu Kuroda 《American journal of transplantation》2005,5(9):2135-2142
Small bowel transplantation (SBT) is associated with a high incidence of infectious complications because of ischemia/reperfusion (I/R) mucosal injury concomitant with potent immunosuppression. In this study, we evaluated whether the cavitary two-layer method (cTLM) could reduce I/R injury and allow early mucosal restoration, particularly after prolonged preservation and transplantation. Canine heterotopic segmental SBT was performed immediately without preservation (group 1), after 24-h preservation in UW solution (group 2) or by the cTLM (group 3). The graft samples were taken 1 h after reperfusion and on days 1, 4 and 7. We assessed graft mucosa with detailed microscopic and electromicroscopic analyses. In Group 3, histological injury and cell apoptosis after transplantation were significantly alleviated and rapidly recovered to a similar level of group 1. The mucosal restoration was morphologically completed within 4 days. In contrast, in group 2, more pronounced mucosal injury and delayed recovery were noted. Crypt cell proliferation activity was well maintained in groups 1 and 3 throughout the experimental period. Our ultrastructural analysis suggested that mitochondrial integrity achieved by the cTLM was a basal mechanism under the prompt mucosal restoration. The cTLM could reduce I/R injury, facilitate mucosal regeneration and restore the nearly normal structure early after SBT. 相似文献
905.
Osteogenic potential of postnatal skeletal muscle-derived stem cells is influenced by donor sex. 总被引:2,自引:0,他引:2
Karin A Corsi Jonathan B Pollett Julie A Phillippi Arvydas Usas Guangheng Li Johnny Huard 《Journal of bone and mineral research》2007,22(10):1592-1602
This study compared the osteogenic differentiation of F-MDSCs and M-MDSCs. Interestingly, M-MDSCs expressed osteogenic markers and underwent mineralization more readily than F-MDSCs; a characteristic likely caused by more osteoprogenitor cells within the M-MDSCs than the F-MDSCs and/or an accelerated osteogenic differentiation of M-MDSCs. INTRODUCTION: Although therapies involving stem cells will require both female and male cells, few studies have investigated whether sex-related differences exist in their osteogenic potential. Here, we compared the osteogenic differentiation of female and male mouse skeletal muscle-derived stem cells (F- and M-MDSCs, respectively), a potential cell source for orthopedic tissue engineering. MATERIALS AND METHODS: F- and M-MDSCs were stimulated with bone morphogenetic protein (BMP)4, followed by quantification of alkaline phosphatase (ALP) activity and expression of osteogenic genes. F- and M-MDSCs were also cultured as pellets in osteogenic medium to evaluate mineralization. Single cell-derived colonies of F- and M-MDSCs were stimulated with BMP4, stained for ALP, and scored as either Low ALP+ or High ALP+ to detect the presence of osteoprogenitor cells. F- and M-MDSCs were transduced with a BMP4 retrovirus (MDSC-BMP4 cells) and used for the pellet culture and single cell-derived colony formation assays. As well, F- and M-MDSC-BMP4 cells were implanted in the intramuscular pocket of sex-matched and sex-mismatched hosts, and bone formation was monitored radiographically. RESULTS AND CONCLUSIONS: When stimulated with BMP4, both F- and M-MDSCs underwent osteogenic differentiation, although M-MDSCs had a significantly greater ALP activity and a larger increase in the expression of osteogenic genes than F-MDSCs. In the pellet culture assay, M-MDSCs showed greater mineralization than F-MDSCs. BMP4 stimulation of single cell-derived colonies from M-MDSCs showed higher levels of ALP than those from F-MDSCs. Similar results were obtained with the MDSC-BMP4 cells. In vivo, F-MDSC-BMP4 cells displayed variability in bone area and density, whereas M-MDSC-BMP4 cells showed a more consistent and denser ectopic bone formation. More bone formation was also seen in male hosts compared with female hosts, regardless of the sex of the implanted cells. These results suggest that M-MDSCs may contain more osteoprogenitor cells than F-MDSCs, which may have implications in the development of cellular therapies for bone healing. 相似文献
906.
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
907.
明胶降解物对大鼠真皮成纤维细胞增殖及Ⅰ型胶原蛋白分泌的影响 总被引:1,自引:0,他引:1
目的 探讨组织工程心瓣膜常用人工基质材料--明胶发生降解后的产物对大鼠真皮成纤维细胞增殖及Ⅰ型胶原蛋白分泌的影响. 方法 利用酶组合技术制备明胶降解物(gelatin hydrolysate, GH),采用超滤的方法分离出低分子量明胶降解物组分(gelatin hydrolysate fraction, GHF),用于5只SD大鼠真皮成纤维细胞的体外培养.采用CCK-8活细胞计数试剂盒(Cell Counting Kit-8)检测细胞的增殖情况,ELISA试剂盒检测细胞I型胶原蛋白的分泌情况. 结果 ①GHF对细胞增殖作用的浓度效应:在0.125~1.0 mg/ml浓度范围内,GHF对细胞的促增殖作用呈现先增强后减弱的趋势,在0.25 mg/ml时,细胞增殖率最大,达到(47.54±16.35)%;②GH与GHF对细胞增殖影响比较:GH与GHF均具有促进细胞增殖的作用,且在浓度为0.25 mg/ml时,促细胞增殖作用无显著差异[(27.04±15.21)% vs (39.22±15.55)%, P=0.177];③GH与GHF对细胞分泌Ⅰ型胶原蛋白影响比较:GHF组第3天时Ⅰ型胶原分泌量为(28.06±5.60)pg/105,与空白对照的(18.24±4.52)pg/105相比,有显著差异(P=0.006),而GH组直至第6天时Ⅰ型胶原蛋白分泌量,与空白对照相比,无统计学意义(P=0.103). 结论 分子量大小不同的明胶降解物GH与GHF均具有促进大鼠真皮成纤维细胞增殖的作用,且分子量较小的GHF还具有促进细胞I型胶原分泌的功能. 相似文献
908.
目的:制备结合凝血酶原复合物(PCC)的阴离子脂膜微泡,评价微泡的理化性质。材料和方法:采用机械振荡直接连接法,分两组(于机械振荡之前或之后加入),制备结合PCC的阴离子脂膜微泡,观察并检测洗涤前后微泡的理化性质。结果:微泡与PCC的结合率及Ⅸ因子活性:两组间比较无明显差异(P>0.05),但洗涤后结合率由洗涤前的95%降为80%,活性由90%降为19%。结论:直接连接法可制备结合PCC的阴离子脂膜微泡,微泡与PCC结合率较高,且洗涤前能保持Ⅸ因子较高的活性。 相似文献
909.
关节镜下人工韧带重建前交叉韧带的临床初步体会 总被引:6,自引:0,他引:6
目的探讨关节镜下应用LARS人工韧带重建前交叉韧带的可行性及近期疗效. 方法用法国产LARS人工韧带对16例前交叉韧带(anterior cruciate ligament,ACL)损伤行关节镜下ACL重建术.等距点钻胫骨、股骨骨道,将肌腱拉入骨道,韧带游离部分位于关节腔内,拉紧后2枚螺钉固定韧带,合并损伤同期处理. 结果手术时间51~86 min,平均64 min.术后无滑膜炎、韧带断裂、活动明显受限等并发症.16例均随访1.5~6个月,平均3.8月.按照IKDC评分标准:术前C级6例,D级10例;术后A级6例,B级9例, C级1例(χ2=6.264,P<0.05).Lysholm膝关节功能评分术前36~76分,(63.7±7.3)分;术后86~97分,(94.8±9.6)分(t=10.356,P<0.05). 结论关节镜下LARS人工韧带重建ACL,操作简便,可使膝关节获得即时稳定性,早期康复锻炼,最大限度的防止关节功能受限,近期疗效满意. 相似文献
910.
BACKGROUND: Deposition of proteins on surfaces of medical devices has been recognized to putatively relate to the process of regulation of biomaterial-associated complications by attachment of fibrin clots, eukaryotic cells, and microbes. The molecules adsorb to a varying extent, depending not only on the physicochemical properties of the biomaterial, but also on the composition of the host fluid. OBJECTIVE: Adsorption of proteins on catheters exposed both ex vivo and in vitro to dialysate of patients on peritoneal dialysis (PD) was studied. METHODS: Peritoneal dialysis effluent was collected from 5 patients with end-stage renal disease on continuous ambulatory PD. Tenckhoff catheters were obtained from 16 patients. Deposition of proteins on excised Tenckhoff catheters and tubing of different materials exposed to PD effluent in vitro was studied using 125iodine-labeled antibodies. Adhesion of Staphylococcus aureus and Staphylococcus epidermidis strains was quantified on tubing exposed to PD effluent in vitro. RESULTS: The presence of albumin, transferrin, immunoglobulin G, fibrinogen, fibronectin, von Willebrand factor, vitronectin, and thrombospondin was determined at various concentrations in PD effluent. All proteins analyzed were detected on PD catheters removed from patients. The extent of protein deposition on Tenckhoff catheters exposed to PD effluent, in vitro, rapidly reached a plateau and remained constant, as it did on polyvinyl chloride and polyethylene tubing. Adhesion of staphylococci was enhanced on Tenckhoff catheters exposed to PD effluent compared to unused PD solution. CONCLUSIONS: The data identify surface exposed proteins that may serve as adhesion sites for microbes on peritoneal catheters indwelled in patients undergoing PD. 相似文献