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排序方式: 共有1185条查询结果,搜索用时 15 毫秒
941.
942.
大鼠离体肝再灌注模型(IPRL)的建立及其在肝移植器官保存液实验中的意义 总被引:11,自引:0,他引:11
目的 为肝脏保存液的研究提供离体肝脏再灌注模型。方法 用大鼠肝移植供体手术方法获取供肝,离体再循环2小时,同健康活体大鼠进行对比,观察胆汁分泌量、胆汁中胆酸及胆红素水平。结果 健康活体大鼠肝和保存时间为0小时的离体再灌注肝的2小时胆汁分泌量分别为206.0±74.8μl 相似文献
943.
944.
Inhibition of neutrophil apoptosis after elective surgery. 总被引:9,自引:0,他引:9
N F Fanning J Porter G D Shorten W O Kirwan D Bouchier-Hayes T G Cotter H P Redmond 《Surgery》1999,126(3):527-534
BACKGROUND: Neutrophils play a crucial role in host defense against infections, but their inappropriate infiltration and activation within tissues can cause host tissue damage through release of reactive oxygen metabolites, metalloproteinases, and proinflammatory cytokines. The termination of a neutrophil-mediated inflammatory response is effected through programmed cell death or apoptosis. Delayed neutrophil apoptosis is associated with proinflammatory diseases, such as the systemic inflammatory response syndrome. Surgery induces a profound inflammatory response; therefore, neutrophil apoptosis of patients undergoing elective surgery was investigated. METHODS: Nonseptic patients undergoing elective orthopedic surgery while under epidural anesthesia had neutrophils and platelet-poor isolated from whole venous blood harvested at 4 time points: pre-epidural, 45 minutes postepidural but before surgical intervention, 1 hour postsurgical incision, and 24 hours postsurgery. Neutrophil apoptosis was quantified at 1, 12, and 24 hours in culture by immunofluorescence flow cytometry of annexin V and propidium iodide staining and confirmed by TUNEL (terminal deoxynucleotidyl transferase nick end labeling) assay for DNA strand breaks. Serum cytokines were quantified by specific enzyme-linked immunosorbent assay. RESULTS: Spontaneous neutrophil apoptosis after elective surgery was significantly (P < .001) inhibited with an effect evident within an hour of surgical incision and persisting at 24 hours postsurgery. The addition of patients' 24 hour postoperative plasma to healthy neutrophils markedly (P < .01) reduced neutrophil apoptosis, whereas plasma taken an hour after surgical incision was ineffective. Interleukin (IL)-6 was notably increased (1395 +/- 196 pg/mL, P < .01) 24 hours postsurgery and at this postoperative concentration inhibited (P < .01) apoptosis of normal neutrophils. Levels of other inflammatory mediators (IL-1 beta, tumor necrosis factor alpha, granulocyte-macrophage colony-stimulating factor, soluble Fas, soluble Fas ligand) were unaltered. The anti-inflammatory cytokine IL-10 was only slightly increased 24 hours postsurgery (8.32 +/- 2.99 pg/mL); however, the addition of recombinant human IL-10 (10 ng/mL) counteracted (P < .05) inhibition of neutrophil apoptosis induced by IL-6 and post-surgery plasma. CONCLUSIONS: These results identify marked inhibition of neutrophil apoptosis after elective surgery and suggest that the inhibition of neutrophil apoptosis in the postoperative period is, at least in part, a result of soluble circulating factors. The marked imbalance favoring proinflammatory over anti-inflammatory cytokine release in the immediate postoperative period mediates the overwhelmingly antiapoptotic net capacity of postsurgery plasma. 相似文献
945.
Van Veldhuisen DJ 《岭南心血管病杂志》1999,5(2):151
标题 a)Ibopamine和地高辛治疗轻到中度的心力衰竭b)在6个月的随访中轻度而未治的心衰之发展及ibopamine和地高辛单疗之效果作者 a)VanVeldhuisenDJ,etal-JAmCollCardiol,1993,22:1564(英文)b)VanVeldhuisenDJ,etal-AmJCardiol,1995,75:796(英文) 研究疾病:轻到中度的心力衰竭。目的:评价ibopamine的疗效和安全性,并将其与地高辛和安慰剂相比较。 设计:随机、双盲和安慰剂对照。病人资料… 相似文献
946.
Oral Diseases (2011) 17 , 241–251 The rapid advancement in basic biology knowledge, especially in the stem cell field, has created new opportunities to develop biomaterials capable of orchestrating the behavior of transplanted and host cells. Based on our current understanding of cellular differentiation, a conceptual framework for the use of materials to program cells in situ is presented, namely a domino vs a switchboard model, to highlight the use of single vs multiple cues in a controlled manner to modulate biological processes. Further, specific design principles of material systems to present soluble and insoluble cues that are capable of recruiting, programming and deploying host cells for various applications are presented. The evolution of biomaterials from simple inert substances used to fill defects, to the recent development of sophisticated material systems capable of programming cells in situ is providing a platform to translate our understanding of basic biological mechanisms to clinical care. 相似文献
947.
Roche-Nagle G Curran J Bouchier-Hayes DJ Tierney S 《Irish journal of medical science》2007,176(3):169-173
Background Venous thromboembolism is a common source of morbidity and mortality but a variety of preventative measures are available.
Aims To audit the current practice of thromboprophylaxis and compare against published protocols.
Methods Three-hundred and seventy-six (376) surgical patients were surveyed prospectively. A Performa was completed recording the
presence of up to 11 risk factors. A risk score was calculated and the use of specific thromboprophylatic measures identified.
Results Heparin thromboprophylaxis was widely used, eight patients (who were on aspirin therapy) failed to receive any prophylaxis
(risk factors 4–6). In addition there were 60 patients at low risk (risk score <2) received LMWH from which they were unlikely
to benefit.
Conclusions Thromboembolic prophylaxis is widely but unselectively applied. Adoption of a risk: benefit ratio approach should ensure those
who would benefit from thromboprophylaxis are adequately treated while those in whom thromboprophylaxis is not indicated are
spared unnecessary therapy. 相似文献
948.
A gamma camera and 99m Technetium were used to obtain transmissionand emission scans of the thorax in order to estimate transthoracictissue thickness, and volumes of blood and interstitial tissuein each pixel of the gamma camera image. This technique hasbeen applied to six patients with stage 2/3 pulmonary sarcoidosisand eight with cryptogenic fibrosing alveolitis and age andsex-matcehed control groups without lung disease. In both conditionstransthoracic tissue thickness was significantly increased:mean values (SD) were 14.6 (1.8) cm in cryptogenic fibrosingalveolitis and 12.3 (2.2) cm in stage 2/3 sarcoidosis. Thiswas partially accounted for by an increase in the interstitialfluid compartment. Blood volume was unaffected. Measurementof transthoracic tissue thickness involves minimal radiationexposure and may be of value in monitoring these diseases; measurementof interstitial fluid volume may give information on diseaseactivity. 相似文献
949.
950.