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51.
OBJECTIVE: To understand the action mechanisms of polydatin (PD) in the treatment of septic shock in view of its effect on lipopolysaccharide (LPS)-induced chemotaxis of the leucocytes. METHOD: Chemotactic chamber assay was used to investigate the regulative role of PD in chemotaxis of the neutrophils in response to LPS stimulation. RESULTS: The chemotactic index of normal neutrophils was 4.96+/-0.69, which was significantly increased by LPS stimulation. LPS stimulation at the doses of 10, 100, and 1000 ng/ml resulted in the elevation of the chemotactic index of the neutrophils to 8.94+/-1.73, 10.31+/-1.180 and 7.12+/-1.46 respectively (P<0.05), an effect potently reversed by the application of PD at the concentrations ranging from 0.008 to 0.8 mg/ml, of which 0.08 mg/ml was the most effective concentration that produced a decrease of the chemotactic index to 1.95+/-0.17. In addition, PD exhibited obvious anti-LPS effect after treatment for 5 to 60 min (P<0.05), while showing no influence on the chemotaxis of normal neutrophils (P>0.05). CONCLUSION: PD can regulate neutrophil chemotaxis in inflammatory reactions and may play a crucial role in the treatment of infections and inflammation. 相似文献
52.
人大肠癌不同转移潜能细胞株SW620及SW480的差异蛋白质组分析 总被引:2,自引:0,他引:2
53.
三七药材指纹图谱的研究 总被引:3,自引:0,他引:3
Fingerprinting of Panax notoginseng was performed by high-performance liquid chromatography using Agilent Hypersil C18 (250.0 mm x 4.0 mm, 5 microm) column with the mobile phase of acetonitrile and water and gradient elution. The detection wavelength was set at 203 nm. The method is simple and reliable to identify and evaluate the quality of Panax notoginseng. 相似文献
54.
伤害控制骨科学--多发伤治疗最新观点 总被引:12,自引:3,他引:9
挽救生命、减少伤残仍是多发伤救治的基本观点,治疗的形式和时机却在逐渐地变化、修正,伤害控制原则是一项新的多发伤治疗策略,其在创伤骨科的应用产生了伤害控制骨科学。伤害控制骨科学包括三步,第一步:早期临时固定不稳定性骨折、止血,如果需要,作颅内减压;第二步:在ICU内复苏病人使其各项生理指标达到理想状态;第三步:病人病情稳定后进行最终的正式手术固定骨折。伤害控制骨科学适应证:血液动力学不稳定及极度危重的多发伤病人应遵循伤害控制原则;对临界病人,仍可早期手术正式固定骨折,但如果手术过程中任何时间发生病情恶化,手术应该立即改为伤害控制。伤害控制骨科学是一项正在发展、完善的技术,将来研究需要进一步验证既有观点的有效性,以减少多发伤病人ARDS和MOF的发生。 相似文献
55.
生物型人工硬脑膜应用的实验研究 总被引:9,自引:0,他引:9
OBJECTIVE: To evaluate the safety and efficacy of a dural graft prepared using porcine membrane in duraplasty. METHODS: Eighteen New Zealand rabbits were randomly divided into groups A (n=4), B (n=4), C (n=5), and D (n=5) sacrificed 3, 14, 30 and 90 d after duraplasty, respectively. Each animal underwent bilateral parietal craniectomy behind the coronal suture and beside the midline to expose the dura, which was cut on the right side and substituted with the dural graft. The exposed dura on the left was kept intact as control. The rabbits were observed for WBC counts before the operation and before sacrifice by transcardiac formalin perfusion, respectively. The meninges and brain tissues were histologically examined after sacrifice. RESULTS: The WBC count varied little after the operation (P>0.05). Microscopic examination demonstrated tissue repair on both the implantation side and control side, without graft adhesion to the cortical surface. In group A, a large number of leukocytes were seen gathering on the lateral dura, suggesting acute tissue repair. In group B, endothelial cells covering the inner surface of the graft could be seen. Fibroblasts and fibrocytes were seen in the grafts between collagen fibers in group C, and in group D, fibroblasts and fibrocytes increased between the collagen fibers and the suture healed. CONCLUSION: The dura graft is safe and applicable for dural defect repair. 相似文献
56.
丙型肝炎病毒感染对肾移植术后影响的临床研究 总被引:3,自引:0,他引:3
Li-xin Yu Zhi-peng Wang Shao-jie Fu Yi-bin Wang Chu-fu Du Jian Xu Wen-feng Deng 《第一军医大学学报》2004,24(6):682-684
OBJECTIVE: To study the influence of hepatitis C virus (HCV) infection on the clinical outcome of kidney transplantation. METHODS: The recipient/graft survival, the incidence of acute/chronic rejection and cause of death in 86 HCV-infected recipients of renal transplantation were compared with those in another 86 recipients without HCV infection. RESULTS: HCV-infected recipients had significantly shorter 5-year survival (74.4%) than those without HCV infection (87.2%, P<0.01). The 1-year (94.2%/90.7% vs 96.8%/96.0%) and 3-year recipient/graft survival rates (88.4%/79.1% vs 90.7%/87.2%), the incidence of acute/chronic rejection (31.3% vs 21.2%, and 12.5% vs 6.5%) and the 5-year graft survival (73.3%/81.4%) were comparable between the two groups (P>0.05). Hepatic disease was identified as the primary cause of mortality. CONCLUSIONS: HCV infection may affect the long-term survival of the recipients with kidney transplantation, and therefore should be considered as a relative contraindication of kidney transplantation. 相似文献
57.
目的 观察刀豆素A(ConA)与小鼠腹腔巨噬细胞表面ConA受体结合、内吞、转运及巨噬细胞自噬、凋亡的形态学变化,以探讨受体介导内吞与自噬体形成和细胞凋亡之间的关系。方法 用辣根过氧化物酶(HRP)标记ConA(ConA-HRP)与小鼠腹腔巨噬细胞共孵育,不同时间取出部分巨噬细胞,制备电镜标本,观察。结果透射电镜观察表明:ConA的内吞属于受体介导内吞;形成的内吞体有泡状、管状及双层膜的线状等形式;双层膜的线状结构包裹部分胞质和细胞器,形成自噬体;自噬体与溶酶体融合,而后巨噬细胞凋亡。结论受体介导内吞和自噬同凋亡之间存在一定的关系。 相似文献
58.
目的探讨p38 丝裂原激活蛋白激酶(MAPK)家族四种亚型对诱导型一氧化氮合酶(iNOS)基因的转录调控。方法以人胚胎肾293(HEK 293)细胞为靶细胞,采用脂质体(LPS)介导的细胞基因共转染技术、荧光素酶报告基因技术,分别将FLAG-tagged p38 MAPK 4种亚型、含有鼠iNOS基因启动子区的荧光素酶报告基因质粒(piNOS-Luc)、空载体(pcDNA3)、β-半乳糖苷酶表达质粒(pCMV-β)共转染,检测并比较荧光素酶相对活性。结果(1)未加刺激时,在HEK 293细胞中,p38 MAPK中仅有p38α能够诱导iNOS基因启动子的转录活性;(2)在LPS刺激下,p38 MAPK 4种亚型均能够诱导iNOS启动子的转录活性,其中,p38β所诱导的转录活性最高,p38α的诱导作用亦很明显。结论(1)LPS能够在HEK 293细胞中诱导iNOS基因转录活性;(2)在HEK 293细胞中,p38 MAPK参与了静息时及LPS刺激下对iN-OS基因的转录调控。 相似文献
59.
目的探讨面神经颅外段的动脉来源及分布. 方法 15例新鲜尸体头颈部标本经双侧颈总动脉插管,加压注入红色乳胶或过氯乙烯填充剂,观察面神经颅外段的血供来源及分布. 结果面神经营养动脉来源于耳后动脉的茎乳动脉、颞浅动脉面神经支、面横动脉、颈外动脉上面神经支、颈外动脉下面神经支、面动脉后面神经支和面动脉前面神经支,其外径分别为(0.8±0.2) mm、(0.9±0.4) mm、(1.9±0.3) mm、(1.0±0.2) mm、(1.1±0.4) mm、(1.0±0.2) mm和(1.1±0.6) mm.各营养动脉除营养面神经外还发出分支相互吻合,构成了丰富的面神经血管网. 结论了解面神经颅外段动脉血供来源及分布,为避免腮腺咬肌区手术损伤面神经营养血管提供了解剖学基础. 相似文献
60.
Agilent 2100 Bioanalyzer在人乳头瘤病毒检测中的应用 总被引:5,自引:1,他引:4
目的:探讨Agilent2100Bioanalyzer芯片分析系统(简称Bioanalyzer)在人乳头瘤病毒(HPV)的PCR检测和分组中的应用。方法:先分别进行通用引物介导PCR(GP-PCR)和型特异性引物介导PCR,扩增HPV高保守区(L1区)的共同序列和各型(包括HPV6,11,16和18型)的特型性序列,然后分别用常规的琼脂糖凝胶电泳技术和Bioanalyzer对PCR产物进行检测,并比较两种检测方法的准确度,重复性和灵敏度。结果:Bioanalyzer在确定片段长度时的准确度和重复性比琼脂糖凝胶电泳高,前者的准确度在95%以上,后者仅为85%,Bioanalyzer的检测灵敏度比琼脂糖凝胶电泳高100倍,结论:Bioanalyzer芯片分析系统结合PCR方法可对HPV进行特异,准确,稳定,灵敏的检测和型别鉴定,具有重要的推广价值。 相似文献