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31.
红细胞调控白细胞免疫功能新的自然实验研究体系 总被引:4,自引:0,他引:4
目的用血液免疫反应路线图实验体系评估红细胞在白细胞免疫活性中的作用。方法将0·3ml血浆加入0·2ml全血细胞悬液(全血细胞组)或0·2ml白细胞悬液(白细胞组)中,37℃温育1h,用免疫酶联法测定IL-8和IL-12水平,流式细胞仪测定白细胞膜CD4、CD8、CD35和CXCR4表达量。结果全血细胞组IL-8和IL-12水平(分别为5·96±4·26、9·84±2·23ρB·pg-1·ml-1)明显低于白细胞组(分别为15·09±9·86、13·59±3·69ρB·pg-1·ml-1,P<0·05),淋巴细胞CD4、CD35、CXCR4表达量(分别为37·79±12·00、154·66±70·00、34·40±20·45)明显高于白细胞组(分别为18·54±11·32、83·26±35·99、16·69±11·09,P<0.01),粒细胞CD35表达量(603·63±257·64)明显高于白细胞组(384·86±174·16,P<0.01)。成人全血细胞组淋巴细胞和粒细胞CD35和CXCR4表达量明显高于脐血全血细胞组(P<0·05或P<0·01)。结论红细胞是白细胞(包括T淋巴细胞、B淋巴细胞、NK细胞、树突状细胞、粒细胞等)免疫功能的调控者和指导者,脐血红细胞免疫调节功能明显下降;本研究为红细胞免疫调控活性测定提供了新的近似自然的方法。 相似文献
32.
腰椎节段形态对峡部、小关节应力及小关节接触力影响的有限元分析 总被引:1,自引:0,他引:1
目的:探讨腰椎形态结构变化对峡部裂性滑脱及小关节退变的作用和意义。方法:采用改良的“非种子区域分割方法”及非平行“最佳切割平面”等一系列新型计算机辅助设计(CAD)方法精确建立包括椎间盘高度、腰椎小关节角、椎间盘前凸角改变的L4~L5活动节段有限元模型;在2700N轴向压缩载荷条件下,分别对各有限元模型的峡部、小关节应力、小关节接触力以及椎间盘负载进行测试。结果:压缩载荷下,腰椎活动节段峡部、小关节等效应力及小关节接触力随椎间盘高度的减小而减小,随小关节角的增大而增加,随椎间盘前凸角的增加而减小。结论:椎间盘高度、腰椎小关节角、椎间盘前凸角等形态结构变化对腰椎节段有限元模型的峡部、小关节应力及小关节接触力有明显的影响。提示腰椎峡部应力性骨折及小关节退变的发生与椎间盘高度、腰椎小关节角、椎间盘前凸角等解剖形态因素有关。 相似文献
33.
Dnyanesh N Tipre James J Fox Daniel P Holt Gilbert Green Jianhua Yu Martin Pomper Robert F Dannals Frank M Bengel 《Journal of nuclear medicine》2008,49(7):1189-1195
The sympathetic nervous system of the heart plays a key role in the pathophysiology of various cardiac diseases. Small-animal models are valuable for obtaining further insight into mechanisms of cardiac disease and therapy. To determine the translational potential of cardiac neuronal imaging from rodents to humans, we characterized the rat sympathetic nervous system using 3 radiotracers that reflect different subcellular mechanisms: (11)C-meta-hydroxyephedrine (HED), a tracer of neuronal transport showing stable uptake and no washout in healthy humans; (11)C-phenylephrine (PHEN), a tracer of vesicular leakage and intraneuronal metabolic degradation with initial uptake and subsequent washout in humans; and (11)C-epinephrine (EPI), a tracer of vesicular storage with stable uptake and no washout in humans. METHODS: We used a small-animal PET system to study healthy male Wistar rats at baseline, after desipramine (DMI) pretreatment (DMI block), and with DMI injection 15 min after tracer delivery (DMI chase). The rats were kept under general isoflurane anesthesia while dynamic emission scans of the heart were recorded for 60 min after radiotracer injection. A myocardial retention index was determined by normalizing uptake at 40 min to the integral under the arterial input curve. Washout rates were determined by monoexponential fitting of myocardial time-activity curves. RESULTS: At baseline, HED showed high myocardial uptake and sustained retention, EPI showed moderate uptake and significant biphasic washout, and PHEN showed moderate uptake and monoexponential washout. The average (+/- SD) left ventricular retention index for HED, PHEN, and EPI was 7.38% +/- 0.82%/min, 3.43% +/- 0.45%/min, and 4.24% +/- 0.59%/min, respectively; the washout rate for HED, PHEN, and EPI was 0.13% +/- 0.23%/min, 1.13% +/- 0.35%/min, and 0.50% +/- 0.24%/min, respectively. The DMI chase resulted in increased washout only for HED. DMI block decreased myocardial uptake of all tracers by less than 90%. CONCLUSION: Kinetic profiles of HED in the rat myocardium were similar to those of HED in humans, suggesting comparable neuronal transport density. Unlike in humans, however, significant washout of EPI and faster washout of PHEN were encountered, consistent with high intraneuronal metabolic activity, high catecholamine turnover, and reduced vesicular storage. This evidence of increased neuronal activity in rodents has implications for translational studies of cardiac neuronal biology in humans. 相似文献
34.
中西医结合治疗急性冠脉综合征临床疗效观察 总被引:3,自引:0,他引:3
目的观察中西医结合治疗急性冠脉综合征(ACS)的临床疗效。方法将60例ACS患者随机分为两组。治疗组在抗血小板、抗凝、降脂、扩张冠状动脉、降压、保护血管内皮功能等常规治疗基础上服用中药复方苏欣康颗粒;对照组在常规治疗基础上加用复方丹参滴丸。2周为1个疗程,1个疗程结束后观察治疗前后临床症状、心电图、24h动态心电图变化,并判定疗效。结果经2周治疗后,治疗组总有效率(90.O%,27/30)显著高于对照组(83.3%,25/30),差异有统计学意义(P〈0.05)。治疗组临床症状的改善程度高于对照组,其中以对心悸、自汗及心肾阳虚的改善最显著(P均〈0.05)。治疗组心律失常发生率(36.7%)低于对照组(50.0%),但差异无统计学意义(P〉O.05)。结论中药复方苏欣康结合常规手段治疗ACS疗效确切,可作为治疗ACS的有效方剂。 相似文献
35.
Yulu Miao Mingxia Zhang Yulin Nie Wan Zhao Bin Huang Zhengming Jiang Shaoxiong Yu Zhibin Huang Hongjin Fu 《中国神经再生研究》2007,2(2):126-128
BACKGROUND: Besides local changes of cranial parenchymal cells, hemorrhage, etc., severe traumatic brain injuries also cause the changes of total body fluid and various functions, and the changes of lymphocytes and T lymphocyte subsets should be paid more attention to. OBJECTIVE: To reveal the changing laws of T lymphocyte subsets after severe traumatic brain injury, and compare with mild to moderate brain injury. DESIGN: A comparative observation. SETTINGS: Department of Neurosurgery, Longgang District Buji People's Hospital of Shenzhen City; Central Laboratory of Shenzhen Hospital of Prevention and Cure for Chronic Disease. PARTICIPANTS: All the subjects were selected from the Department of Neurosurgery, Longgang District Buji People's Hospital of Shenzhen City from August 2002 to August 2005. Thirty patients with severe brain injury, whose Glasgow coma score (GCS) was ≤ 8 points, were taken as the experimental group, including 21 males and 9 females, aging 16 - 62 years. Meanwhile, 30 patients with mild traumatic brain injury were taken as the control group (GCS ranged 14- 15 points), including 18 males and 12 females, aging 15 -58 years. All the subjects were in admission at 6 hours after injury, without disease of major organs before injury Informed consents were obtained from all the patients or their relatives. METHODS: (1) The T lymphocytes and the subsets in peripheral blood were detected with immunofluorescent tricolor flow cytometry at l, 3, 7 and 14 days after injury in both groups. (2) The conditions of pulmonary infections were observed at 4 days after injury. The differences of measurement data were compared with the t test. MAIN OUTCOME MEASURES: Changes of T lymphocytes subsets at 1 - 14 days after severe and mild or moderate traumatic injury. RESULTS: Finally, 28 and 25 patients with mild to moderate traumatic brain injury, whereas 25 and 21 patients with severe traumatic brain injury were analyzed at 7 and 14 days respectively, and the missed ones died due to the development of disease. (1) Changes of T lymphocyte subsets: At 1 and 3 days after injury, CD3, CD4, CD8, CD4/CD8 began to decrease, whereas CD8 increased in the experimental group, which were very significantly different from those in the control group (t =2.77 - 3.26, P 〈 0.01), and began to recover at 7 days, which were significantly different from those in the control group (t = 2.06 - 2.24, P 〈 0.05), and generally recovered to the normal levels at 14 days (P 〉 0.05). (2) Conditions of pulmonary infections: At 4 days after injury, the rate of pulmonary infection was significantly different between the experimental group and control group [73% (22/30), 0, x2=37.29, P 〈 0.01]. CONCLUSION: Patients with severe traumatic brain injury suffer from damages of cellular immune function at early period (within 7 days), and they are easily to be accompanied by pulmonary infections. 相似文献
36.
Single or combined monoclonal antibodies (McAbs) Zh53, Zh820, and Zh2-1 have been used to eliminate malignant clonogenic cells from human bone marrow. The test of cytotoxicity showed that all of these McAbs could express high specific cytotoxic action against HL-60 cells and were selectively complement-dependent cytotoxic to various types of fresh leukemic cells. Clonogenic assay detected that single treatment with antibody and rabbit complement (RC) could reduce clonogenic units of HL-60 cells by more than 2 logs and two treatments reduced clonogenic units by more than 4 logs. However, combination of 2 McAbs could reduce clonogenic units by 4-5 logs. The data suggest that multiple treatments with McAbs and RC or a combination of 2 McAbs are more effective than a single treatment in eliminating clonogenic tumor cells. Treatment of normal human bone marrow with Zh53, Zh2-1 and RC did not produce a loss of normal CFU-GM, but treatment with Zh820 reduced the clonic units of normal CFU-GM by 24%.
相似文献
37.
38.
V. E. Kataev O. I. Militsina I. Yu. Strobykina G. I. Kovylyaeva R. Z. Musin O. V. Fedorova G. L. Rusinov M. N. Zueva G. G. Mordovskoi A. G. Tolstikov 《Pharmaceutical Chemistry Journal》2006,40(9):473-475
Diesters based on isosteviol and dicarboxylic acids were synthesized and tested for antituberculous activity. Isosteviol and
some of its derivatives exhibit appreciable tuberculostatic properties in vitro, the activity being dependent on the length of the polymethylene spacer connecting two ent-beyeran fragments. The mechanism of the antituberculous action of isosteviol derivatives are discussed.
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Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 40, No. 9, pp. 12–13, September, 2006. 相似文献
39.
40.