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41.
血管内皮生长因子及炎性因子在油酸性犬急性呼吸窘迫综合征中的变化 总被引:1,自引:0,他引:1
目的探讨油酸性急性呼吸窘迫综合征(ARDS)beagle犬血浆及肺泡灌洗液血管内皮生长因子(VEGF)、可溶性细胞间黏附分子-1(ICAM-1)、白细胞介素-8(IL-8)、肿瘤坏死因子-α(TNF—α)水平的改变。方法12只英国纯种beagle犬,静脉注射油酸0.15mL/kg,在注射油酸前、后1h,出现ARDS的典型表现时,抽血测VEGF、sICAM-1、IL-8、TNF—α,并对此时相作肺泡灌洗液VEGF、sICAM—1、IL-8、TNF-α的测定。结果beagle犬静脉注射油酸后1h血浆TNF—α升高(P〈0.05),血浆反肺泡灌洗液IL8、sICAM-1和VEGF在1h较油酸前没有明显变化(P〉0.05),beagle犬油酸型ARDS模型建立后血浆及肺泡灌洗液VECF、sICAM-1、IL-8、TNF—α均显著高于建模前(P〈0.05)。结论VEGF、sICAM-1、IL-8、TNF~α在beagle犬油酸型ARDS发生发展过程中可能均起重要作用,其水平的高低可能与ARDS严重程度及预后有关。 相似文献
42.
目的探讨转染人血管内皮生长因子(VEGF)基因对大鼠胰岛移植物再血管化和生物学功能的影响。方法实验分二步进行,首先构建携带人血管内皮生长因子165(hVEGF165)基因的重组腺病毒载体AdhVEGF165,用其按病毒/细胞的感染倍数(MOI)分别为10、100、500的比例在体外转染新鲜分离、纯化的近交系Lewis大鼠胰岛,检测体外培养的胰岛表达hVEGF165基因的情况;然后按MOI为10的比例在体外用AdhVEGF165转染Lweis大鼠胰岛,再经门静脉注射至近交系Lewis大鼠的肝脏内(VEGF组),并设不含hVEGF165基因的空载体转染对照组(GFP组)和磷酸盐缓冲液处理对照组(PBS液组),术后测定受鼠的血糖变化,进行静脉糖耐量试验(IVGTT),并观察受鼠肝脏中移植胰岛的组织学变化。结果体外转染hVEGF165基因的大鼠胰岛分泌至细胞外的hVEGF165的浓度显著高于未转染者(P〈0.01)。糖尿病大鼠移植转染hVEGF165基因的胰岛后,静脉注射葡萄糖后40、60、120min时的血糖水平显著低于GFP组和PBS液组(P〈0.05);40min时体循环中胰岛素的浓度,VEGF组显著高于GFP组和PBS液组(P〈0.05);VEGF组移植胰岛内CD34和胰岛素免疫组化染色的强度均高于GFP组和PBS液组。结论转染hVEGF165基因对胰岛移植物的再血管化和生物学功能有促进作用。 相似文献
43.
Vascular malformation (AVM) in the gastrointestinal tract is an uncommon, but not rare, cause of bleeding and iron deficiency anemia, especially in an aging population. While endoscopic coagulative therapy is the method of choice for controlling bleeding, a substantial number of cases require additional therapy. Adjunctive or even primary phamacotherapy may be indicated in recurrent bleeding. However, there is little evidence-based proof of efficacy for any agent. The bulk of support is derived from anecdotal reports or case series. The present review compares the outcome of AVM after no intervention, coagulative therapy or focus on pharmacological agents. Most of the literature encompasses two common AVMs, angiodysplasia and hereditary hemorrhagic telangiectasia. Similarly, the bulk of information evaluates two therapies, hormones (estrogen and progesterone) and the somatostatin analogue octreotide. Of these, the former is the only therapy evaluated in randomized trials, and the results are conflicting without clear guidelines. The latter therapy has been reported only as case reports and case series without prospective trials. In addition, other anecdotally used medications are discussed. 相似文献
44.
分子靶向药物bevacizumab是针对血管内皮生长因子(VEGF)的重组人源化单克隆抗体,在多种恶性肿瘤的治疗中显示了临床效果。现就bevacizumab的作用机制及其在乳腺癌治疗中的临床研究进展作一综述。 相似文献
45.
目的:评价耳蜗神经电位活动直接监护在听神经瘤手术中对保护听力的作用。方法:听神经瘤手术中施行耳蜗电图监护。结果:16例听神经瘤手术中施行耳蜗电图监护者,术后听力保留5例(31%),其中4例为有效听力保留。肿瘤在2厘米以下者听力保留为38%(5/13)。结论:听神经瘤手术过程中采用耳蜗电图监护,能敏感地反应即时的听神经功能状况,给术者及时的反馈信息,有助于听力保护 相似文献
46.
Stephen R. Thomas Ronald G. Pratt Ronald W. Millard R. C. Samaratunga Yoseph Shiferaw Leland C. Clark Richard E. Hoffmann 《Journal of magnetic resonance imaging : JMRI》1994,4(4):631-635
Oxygen-sensitive F-19 magnetic resonance imaging of perfluorocarbon compounds requires that fluorocarbon T1 changes correlate with the local Po2 and not with the composition of the surrounding aqueous phase. The influence of various bioconstituents and paramagnetic ions within the aqueous phase on the F-19 fluorocarbon phase T1 for PFC emulsions was evaluated at 0.14 and 0.66 T. T1 was measured for FC-43, perflubron, and a fluorinated surfactant. Controlled variables introduced in the aqueous phase included annex solution constituents, blood, pH changes, and Gd-DTPA. For a constant Po2, the F-19 T1s were independent of the emulsion constituents, blood concentration, and pH. For FC-43 and perflubron, F-19 T1 was independent of the Gd-DTPA concentration, while the aqueous phase T1 decreased by more than an order of magnitude. XMO-10 (smallest emulsion particle size) showed a slight decrease in F-19 T1 with increasing Gd-DTPA concentration at 0.66 T. 相似文献
47.
Hitoshi Tajiri M.D Kosuke Kozaiwa M.D Tokuzo Harada M.D Yoshikazu Ozaki M.D Kazunori Miki M.D Kazuo Shimizu M.D Shintaro Okada M.D. 《Pediatrics international》1991,33(3):323-326
We assessed the efficacy of a government-sponsored mass protection program in Osaka, Japan, for perinatal HBV infection in infants born to HBeAg positive HBV carrier mothers. We also evaluated the impact of optional follow-up procedures in such infants, including an evaluation of anti-HBs response and a booster dose of HBV vaccine for poor responders. The results demonstrated that this mass protection program protected 94.4% of the infants from perinatal HBV infection in the Osaka area. However, the proportion of infants with an unprotective level of anti-HBs was higher in the standard group than in the follow-up group both at 1.0 and 1.5 years of age, which was also the case for HBV events. Furthermore, the present study showed that a booster dose of vaccine in poor responders was very effective in promoting an anti-HBs response. In conclusion, we recommend that a follow-up blood test to confirm a response of anti-HBs to HBV vaccine should be performed at 4–8 weeks after the third injection of HBV vaccine in infants born to HBeAg positive HBV carrier mothers. We also recommend that a booster injection of HBV vaccine should be immediately given to poor responding infants who otherwise are at a considerable risk of developing HBV infection in late infancy. 相似文献
48.
Kevin L. Greason M.D. Jose A. Acosta M.D. Thomas J. Magrino M.D. Moogil Choe M.D. 《Diseases of the colon and rectum》1996,39(6):702-704
PURPOSE: This study was undertaken to clarify the importance of bleeding vascular ectasia of the colon as the etiology of massive lower gastrointestinal hemorrhage in patients 40 years of age or younger. METHODS: An otherwise healthy 21-year-old male was admitted to a tertiary medical center with massive lower gastrointestinal hemorrhage. Technetium-labeled red blood cell scan, selective visceral angiography, and colonoscopy identified the source of bleeding as vascular abnormality of the descending colon. Segmental colonic resection was performed. RESULTS: Histologic review of the specimen demonstrated a vascular ectasia. The patient recovered uneventfully and has had no further stigmata of hemorrhage. A review of the literature was undertaken to make clear the significance of vascular ectasia as the source for massive colonic hemorrhage in the young adult. CONCLUSION: This is the first report that documents histologically a vascular ectasia as the source of massive lower gastrointestinal hemorrhage in an otherwise healthy patient less than 40 years of age. Vascular ectasia is an uncommon cause of lower gastrointestinal hemorrhage in the young adult.The Chief, Bureau of Medicine and Surgery, Navy Department, Washington, DC, Clinical Investigation Program sponsored this report #84-16-1968-532, as required by HSETCINST 6000.41A. The views expressed in this article are those of the authors and do not reflect the official policy or position of the Department of the Navy, Department of Defense, or the United States Government. 相似文献
49.
50.
肿瘤抑制因子PTEN蛋白在自发性高血压大鼠主动脉平滑肌中的表达 总被引:1,自引:0,他引:1
目的:研究PTEN蛋白在雄性自发性高血压大鼠及SD大鼠主动脉中的表达。方法:取18周龄和26周龄雄性自发性高血压大鼠及同龄雄性SD大鼠主动脉石蜡包埋切片,免疫组织化学观察PTEN在主动脉平滑肌细胞中的表达。结果:SD大鼠主动脉平滑肌细胞中存在PTEN阳怀免疫反应产物。自发性高血压大鼠主动脉平滑肌细胞也存在PTEN阳性免疫反应产物,但免疫反应产物的染色强度明显低于SD大鼠。结论:SD大鼠主动脉平滑肌细胞PTEN高表达,自发性高血压大鼠主动脉平滑肌细胞PTEN表达呈下降趋势。提示PTEN可能在自发性高血压大鼠主动脉平滑肌细胞重塑过程中发挥作用。 相似文献