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101.
J. M. Rothfeld J. F. Hejtmancik P. M. Conn D. W. Pfaff 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1987,69(1):113-118
Summary The slow potential change (spc) accompanying spreading depression (SD) was studied in rats and in a seizure-sensitive strain of Mongolian gerbil under three different experimental paradigms, each involving the use of naloxone. Gerbils undergoing electroconvulsive shock treatment displayed SD during the post-ictal phase, which was blocked by the intraperitoneal (i.p.) administration of naloxone (20–50 mg kg-1). Topical application of naloxone to the exposed cortex of the anaesthetized gerbil and rat blocked the spc of SD evoked by KCl. Microiontophoretic ejection of naloxone during extracellular recordings reversed cell refractoriness following the spc, demonstrated by the observation of a maintained sensitivity to iontophoretic pulses of glutamate. The results suggest a possible involvement of naloxone-sensitive processes in the mechanism responsible for cortical SD. 相似文献
102.
热休克蛋白60对小鼠树突状细胞功能影响体外研究 总被引:1,自引:0,他引:1
目的:探讨动脉粥样硬化中重要炎性物质——热休克蛋白60(HSP60)体外对小鼠树突状细胞(mDC)功能影响.方法:小鼠骨髓提取DC,体外培养成熟后与两种浓度mHSP60孵育,动态观察DC突起改变;流式细胞仪检测孵育前后mDC表面标志改变;MLR测定孵育前后mDC刺激功能变化;ELISA法测定MLR上清液中细胞因子浓度.结果:孵育后,mDC突起增加明显;CD11c^+、CD80及CD86表型显著增加;淋巴细胞刺激功能明显增强;分泌细胞因子IL-12、IFN-γ增加(P<0.01)而IL-4增加不明显(P>0.05),IFN-γ/IL-4比值升高.结论:mHSP60体外可以促进mDC功能,作用呈剂量依赖性. 相似文献
103.
ESWL实际焦点位置的理论和数值分析 总被引:6,自引:1,他引:6
从理论和数值模拟两个方面分析了ESWL中的非线性的动力学焦点和实际焦点的位置 ,给出三种典型的动力学焦点的数值结果 ,说明非线性动力学焦点和实际焦点一般不是几何焦点 ,指出正确确定实际焦点在ESWL技术中的重要性。 相似文献
104.
Eva Müller Wolfgang Neuhofer Akihiro Ohno Silvia Rucker Klaus Thurau Franz-X. Beck 《Pflügers Archiv : European journal of physiology》1996,431(4):608-617
The distribution of heat shock proteins (HSP) HSP60, HSP73, HSP72 and HSP25 in the isoosmotic cortex and the hyperosmotic medulla of the rat kidney was investigated using Western blot analysis and immunohistochemistry. HSP73 was homogeneously distributed throughout the whole kidney. The level of HSP60 was high in the renal cortex and low in the medulla. HSP25 and HSP72 were present in large amounts in the medulla. Only low levels of HSP25 and almost undetectable amounts of HSP72 were found in the cortex. HSP25 exists in one nonphosphorylated and several phosphorylated isoforms. Western blot analysis preceded by isoelectric focussing showed that HSP25 predominates in its nonphosphorylated form in the outer medulla but in its phosphorylated form in cortex and inner medulla. Although this intrarenal distribution pattern was not changed during prolonged anaesthesia (thiobutabarbital sodium), a shift from the nonphosphorylated to the phosphorylated isoforms of HSP25 occurred in the medulla. The characteristic intrarenal distribution of the constitutively expressed HSPs (HSP73, HSP60, HSP25) may reflect different states of metabolic activity in the isoosmotic (cortex) and hyperosmotic (medulla) zones of the kidney. The high content of inducible HSP72 in the medulla most likely is a consequence of the osmotic stress imposed upon the cells by the high urea and salt concentrations in the hyperosmotic medullary environment. 相似文献
105.
Prevention of endotoxin shock by an antibody against leukocyte integrin {beta}2 through inhibiting production and action of TNF 总被引:2,自引:0,他引:2
Watanabe Shun-ichi; Mukaida Naofumi; Ikeda Naoki; Akiyama Mariko; Harada Akihisa; Nakanishi Isao; Nariuchi Hideo; Watanabe Yoh; Matsushima Kouji 《International immunology》1995,7(7):1037-1046
Septic shock remains a serious disorder associated with highmortality. Accumulating evidence indicates that TNF is a majorand essential mediator of endotoxin shock. We report here thatadministration of an antibody against CD18 dramatically reducedendotoxin-induced shock inrabbits as revealed by preventionof severe hypotension, metabolic acidosis and a pathologicalchange suggestive of disseminated intravascular coagulationwith concomitant inhibition of elevation of plasma TNF activity.The anti-CD18 antibody also inhibited the hypotension inducedby administering recombinant TNF. Furthermore, an antibody againsta ligand for CD18 complexes, intercellular adhesion molecule-1,also prevented TNF-induced shock as well as endotoxin shockinrabbits. These observations suggest that adhesion of leukocytesto endothelium may be of primary importance in the action ofTNF as well as in the production of TNF in vivo and that theantibody against adhesion molecules could be of therapeuticbenefit in life-threatening septic shock in humans. 相似文献
106.
空肠弯曲菌HSP43诱导自身免疫机理──分子模拟和抗原优势 总被引:3,自引:0,他引:3
我们曾发现空肠弯曲菌43kD热休克蛋白(HSP43)能诱导小鼠产生自身免疫应答,本文则进一步分析了这种诱导作用的机理。二株针对HSP60保守区序列的单克隆抗体IIH9和ML-30不但能结合人及小鼠细胞中HSP60家族成员,而且也能结合HSP43,表明HSP43、人及小鼠HSP60三者均属同一家族成员,具有序列上的高度同源性。小鼠用空肠弯曲菌免疫后出现了针对10种菌体蛋白的抗体,其中最早被诱导的抗体是针对HSP43的,并且该种抗体在随后80d观察期间内保持了较高活性,表明HSP43是优势抗原。本文结果提示,HSP43较易被免疫系统识别而产生应答,通过和宿主HSP60高度序列同源性而可能呈现分子模拟,从而诱导自身免疫损伤。 相似文献
107.
L. C. Pele S. J. Thompson B. Kirkham R. P. H. Thompson J. J. Powell 《Inflammation research》2007,56(4):143-148
Objectives: The aims of this study were to determine, in peripheral blood mononuclear cells (PBMC), whether particulate antigen triggers
(i) an amplified cell proliferative response compared to soluble antigen and (ii) a dysfunctional response in cells derived
from patients with chronic inflammation and specifically in those with inflammatory bowel disease (IBD).
Subjects: Healthy volunteers (n = 17), inflammatory controls (n = 8) and patients with IBD (n = 17) were recruited from St Thomas’ and
Guys’ Hospital, London, UK.
Methods: Following optimisation of experimental conditions (0.1–10.0 μg/ml antigen), PBMC were stimulated with (i) 10.0 μg/ml recombinant
soluble heat shock protein 65 (hsp 65) and (ii) 1.0 and 10.0 μg/ml hsp 65 conjugated to microparticles (0.5 μm diameter).
PBMC proliferative responses were measured by 3H-Thymidine incorporation at day 5 and results compared between groups using unpaired t-test.
Results: Conjugation to microparticles of low dose hsp 65 significantly increased overall proliferative responses by 2–11 fold compared
to soluble antigen alone (p < 0.05). However, no specific PBMC proliferative dysregulation was noted in cells from subjects
with IBD.
Conclusions: Low dose antigen, in microparticulate form, leads to amplified cell proliferation in primary human cells, as showed previously
in cell lines and animal studies. However there is no abnormal proliferative response in cells from subjects with IBD.
Received 8 February 2006; returned for revision 7 March 2006; accepted by G. Wallace 25 October 2006 相似文献
108.
The present experiment explored the utility of finger pulse volume (FPV) as a measure of anxiety. Subjects were exposed to either a threatening or nonthreatening situation, and indices of physiological arousal (pulse rate (PR) and FPV) and self-report of anxiety (Affect Adjective Checklist (AACL)) were collected. Results indicated that FPV was responsive to changes in experimentally induced anxiety and significantly correlated with PR and AACL, although the strength of these relationships was not substantial. Relevance for psychophysiological theory and the clinical observation of anxiety is discussed. 相似文献
109.
Elevated plasma levels of the long pentraxin, pentraxin 3, in severe dengue virus infections 总被引:4,自引:0,他引:4
Mairuhu AT Peri G Setiati TE Hack CE Koraka P Soemantri A Osterhaus AD Brandjes DP van der Meer JW Mantovani A van Gorp EC 《Journal of medical virology》2005,76(4):547-552
C-reactive protein is one of the most widely used indicators of the response of acute-phase proteins. The measurement of C-reactive protein in dengue, however, is clinically not useful, because of marginally elevated levels and absent association with disease severity. The prototypic long pentraxin, pentraxin 3, is an acute phase protein that is structurally related but distinct from C-reactive protein which has proven to correlate with the severity of bacterial infection in critically ill patients. The potential involvement of pentraxin 3 in dengue and its aptitude to predict more severe disease or poor clinical outcome has not been studied previously. We therefore measured pentraxin 3 plasma levels in 44 dengue virus infected patients. Pentraxin 3 levels were strikingly higher when compared to C-reactive protein levels, with highest pentraxin 3 values observed in the first 7 days after the onset of symptoms. Median pentraxin 3 levels at admission and peak levels during follow up were higher in patients suffering from dengue shock syndrome (at admission: 119.3 ng/ml [interquartile range 61.8--188.7], peak values during follow up: 147.9 ng/ml [interquartile range 85.7--204.3]) compared to levels found in patients with dengue fever and dengue hemorrhagic fever (at admission: 59.0 ng/ml [interquartile range 28.6--100.3], P=0.040; peak values during follow up: 80.8 ng/ml [interquartile range 36.1--168.1], P=0.020). Our results indicate that pentraxin 3 seems to be a marker of infection better than C-reactive protein in dengue. The role of pentraxin 3 in the pathogenesis of dengue and its potential as an early prognostic indicator of disease severity needs further assessment. 相似文献
110.
目的:探讨心理应激对海马CA3区神经元凋亡的影响,热休克蛋白70(Hsp70)对心理应激引起的海马CA3区神经元凋亡的保护作用。方法:建立心理应激、热应激(Heat Shock Pretreatment)、心理应激加热应激三种动物模型,利用免疫组化和TUNEL分别检测海马CA3区神经元在第1、2、3个月三个时间段的Hsp70表达和神经元凋亡水平。结果:有心理应激的各组动物海马凋亡神经元数高对照组(P<0·05),热应激加心理应激组凋亡神经元在2、3个月时较同时段心理应激组下降(P<0·05),但热应激组与对照组间差异没有显著性。有热应激各组Hsp70表达数高于无热应激的两组(P<0·01)。海马CA3区Hsp70表达水平与神经元调亡水平呈负相关(r=-0·26,P=0·03)。结论:热应激可促进海马Hsp70的表达,热休克蛋白70对心理应激导致的海马CA3区神经元损伤有保护作用。 相似文献