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1.
为探讨正常大鼠与吞噬功能缺陷大鼠视网膜色素上皮(RPE)和视杆细胞外节(ROS)膜表面的甘露糖受体的存在和分布,本实验用胶体金标记物对12只Wistar大鼠和12只RCS大鼠的RPE细胞及临近其顶部的ROS表面的Con-A受体进行标记.结果表明。两种大鼠RPE细胞及ROS膜表面均有胶体金标记物.胶体金标记物在两种RPE细胞微绒毛上分布密度较低,而在两种大鼠ROS膜表面分布密度则高。说明两种大鼠RPE细胞和ROS膜表面均有Con-A受体分布。在两种大鼠ROS被RPE细胞吞入后,均无胶体金标记物。  相似文献   

2.
小狼毒的新多取代二萜酯和麦角甾醇型三萜新成分   总被引:1,自引:0,他引:1  
小狼毒的新多取代二萜酯和麦角甾醇型三萜新成分张峻,杨成金,吴大刚(中国科学院昆明植物研究所植物化学开放实验室,昆明650204)ANEWPOLYSUBSTITUTEDDITERPENESTERANDERGOSTANOLTYPENEWTRITERPEN...  相似文献   

3.
急性缺氧对事件关联电位的影响*李鲁平马瑞山1程宏伟1王兴邦1程敬之(西安交通大学生物医学工程系,西安710049;1第四军医大学空医系)通常事件关联电位(event-relatedpotentials,ERP)由叠加平均获得,所以掩盖了逐次ERP的差...  相似文献   

4.
本实验采用免疫组织化学ABC-GDN法和地高辛标记寡核苷酸探针原位杂交技术,研究了降钙素基因相关肽(CGRP)及其mRNA在恒河猴内的表达。结果显示CGRP分布于恒河猴肺内各级支气管粘膜上皮的神经内分泌细胞(NEC)和神经上皮样小体(NEB)中。CGRP杂交阳性细胞的分布与免疫组织化学的结果相同。CGRP mRNA杂交信号均匀分布于整个细胞质,而CGRP免疫反应物仅在神经内分泌细胞的基部更明显,说  相似文献   

5.
我们采用不同组块数的汉字词组作为刺激事件,研究了在短时记忆过程中40Hz脑电事件相关电位(40Hz ERPs)的分维特性。通过短时记忆容量与40Hz ERPs分维特性的相关分析,发现在测试组块数在7附近时,40Hz ERPs分维数分形维数特性发生了突变,表现为左右半球分维数值相对大小的反转和同一半球内分维数的突降。这与心理学分析得到的汉字短时记忆容量在6、7个组块数附近的结合相吻合。  相似文献   

6.
脑电信息处理是脑功能研究重要组成部分。本文介绍了脑电信息处理的前沿领域,包括诱发电位、事件相关电位(ERP)、正弦调制光(声)诱发脑电、40HzERP和脑电非线笥动力学研究,并论及了认知活动与分形维数的关系。  相似文献   

7.
本研究在离体大鼠肠系膜血管床灌流模型上,采用特异放免法测定灌流液中的降钙素基因相关肽(CGRP),观察几种常见炎症介质在内毒素引起CGRP释放中的作用。结果显示:前列腺素合成酶抑制剂地塞米松、布洛芬与消炎痛,缓激肽受体B2拮抗剂HOE140,血小板激活因子拮抗剂WEB2086,组胺H1受体拮抗剂苯海拉明以及和组胺H2受体拮抗剂西咪替丁,均能明显抑剂制内毒素引起的CGRP释放,5羟色胺受体拮抗剂ICS205930却无明显作用。从而提示:内毒素引起CGRP释放是通过炎症介质前列腺素、缓激肽、血小板激活因子和组胺介导的,阻断或减少炎症介质的产生可望减轻内毒素血症时CGRP的过量释放。  相似文献   

8.
降钙素基因相关肽拮抗内皮素的致心律失常作用   总被引:6,自引:0,他引:6  
本工作在麻醉大鼠冠状动脉口注射内皮素1(ET1)900pmol/kg能引起室性早搏(PVC)、室速(VT)、室颤(VF)等严重心律失常,心律失常评分(AS)为5.6±1.0;冠状动脉口单独注射降钙素基因相关肽(CGRP)300-1200pmol/kg仅引起血压一过性下降,此后逐渐恢复,无心律失常发生,心律失常评分为0。用CGRP300pmol/kg预处理后再注射ET1900pmol/kg,心律失常发生率减少,严重程度降低,AS为1.6±1.6。CGRP1200pmol/kg+ET1组心律失常评分显著低于ET1对照组(P<0.01)。本实验结果表明,CGRP的抗心律失常作用很可能有部分是通过拮抗内皮素的致心律失常作用来实现的。  相似文献   

9.
本工作目的是在离体大鼠肠系膜动脉床灌流模型上,观察几种常见炎症介质:前列腺素E2(PGE2)、缓激肽(BK)、组胺(HIS)、血小板活化因子(PAF)及5-羟色胺(5-HT)对血管周围感觉神经介质CGRP释放的直接影响。结果显示:PGE2(1-100μmol/L)和BK(5-10μmol/L)能引起大鼠肠系膜动脉床时间和浓度依赖性地释放CGRP。HIS,PAF和5-HT则未见明显作用。结果提示,PGE2与BK可能是引起血管周围感觉神经兴奋和CGRP释放的主要炎症介质。  相似文献   

10.
本研究在离体大鼠肠系膜血管床灌流模型上,采用特异放免法测定灌流液中的降钙素基因相关肽(CGRP)观察几种常见炎症介质在内毒素引起CGRP释放中的作用,结果显示:前列腺素合成酶抑制剂地塞米松,布洛芬与消炎痛,缓激肽受体B2拮抗剂HOE-140,血小板激活因子拮抗剂WEB2086,组胺H1受体拮抗剂苯海拉明以及和组胺H2受体拮抗剂西咪替丁,均能明显抑剂制内毒素引起的CGRP释放,5羟色胺受体拮抗剂IC  相似文献   

11.
Several pieces of experimental evidence indicate the following: 1) the most efficient antitumor treatments (this principle applies on both chemotherapy and radiotherapy) are those that induce immunogenic cell death and are able to trigger a specific antitumor immune response; and 2) the immunogenicity of cell death depends very closely on the plasma membrane quantity of calreticulin (CRT), an endoplasmic reticulum (ER) stress protein exposed to the cell membrane after immunogenic treatment. Nevertheless, the mechanisms implicated in CRT translocation are unknown. CRT is known to interact in the ER with ERP57, another ER stress protein. I sought to determine whether ERP57 would have any role in tumor immunogenicity. In this article I report that CRT exposure is controlled by ERP57 exposure. CRT and ERP57 are translocated together in the same molecular complex. ERP57 knockdown suppressed CRT exposure as well as phagocytosis by dendritic cells and abolished the immunogenicity in vivo. Knockdown or the absence of CRT abolishes ERP57 exposure. Administration of recombinant ERP57, unlike the administration of recombinant CRT, did not restore the immunogenicity of CRT or ERP57 small interfering RNA-transfected tumor cells. Together, these studies identify ERP57 as a key protein that controls immunogenicity by controlling CRT exposure and illustrate the ability of ERP57 to serve as a new molecular marker of immunogenicity.  相似文献   

12.
生态系统服务研究在生态红线政策保护成效评估中的应用   总被引:3,自引:0,他引:3  
江波  王晓媛  杨梦斐  蔡金洲 《生态学报》2019,39(9):3365-3371
生态保护红线政策是中国推进生态保护与建设的宏观政策,其保护成效评估是国内外关注的重大科学问题。在分析国内外生态系统服务研究进展及中国生态保护红线内涵、划定进程及管控要求的基础上,结合生态红线政策与生态系统服务研究的关联及生态系统服务研究在红线政策保护成效评估应用中面临的挑战,提出了红线政策实施效果评估的技术框架和基本思路。开展生态红线政策保护成效评估,能从科学上明确生态红线政策实施对多尺度利益相关者成本、效益的影响,为生态红线政策的综合研究提供框架和科学方法;从政策设计上,为生态红线布局进一步优化提供依据;从制度建设上,提出符合生态红线政策实施的制度框架,推动生态保护红线制度建设由理论走向实践。  相似文献   

13.
Event-related potentials (ERP) are informative indicators of higher nervous activity of healthy people and patients in pathological states. Traditionally, methods of ERP processing include peak-time characteristics, topographical mapping and localization of equivalent dipole sources. At the same time, estimation of ERP synchronization is complicated by a short duration of the process. The wavelet analysis makes it possible to overcome the disadvantages of the traditional Furrier analysis and to calculate characteristics of ERP synchronization, in particular, phase synchronization. A new approach to estimation of the auditory ERP in healthy persons is proposed in the article. The method is based on the analysis of phase wavelet-synchronization of ERP individual components under conditions of differentiation of different degrees of attention concentration in healthy persons.  相似文献   

14.
Previous studies have shown that the amplitude and phase of the steady-state visual-evoked potential (SSVEP) can be influenced by a cognitive task, yet the mechanism of this influence has not been understood. As the event-related potential (ERP) is the direct neural electric response to a cognitive task, studying the relationship between the SSVEP and ERP would be meaningful in understanding this underlying mechanism. In this work, the traditional average method was applied to extract the ERP directly, following the stimulus of a working memory task, while a technique named steady-state probe topography was utilized to estimate the SSVEP under the simultaneous stimulus of an 8.3-Hz flicker and a working memory task; a comparison between the ERP and SSVEP was completed. The results show that the ERP can modulate the SSVEP amplitude, and for regions where both SSVEP and ERP are strong, the modulation depth is large.  相似文献   

15.
A monoclonal antibody was developed against an 8,000-kDa enzyme-releasing peptide (ERP) released from human alveolar macrophages. ERP was isolated on an immunoaffinity column containing the antibody bound to staphylococcal protein A-Sepharose. Release of ERP from the macrophages is not changed by plastic adherence, phagocytosis, calcium ionophore, or phorbol esters. The peptide was not antigenically similar to interferon-gamma, tumor necrosis factor, or interleukin 1 alpha or 1 beta. The release of constituents from azurophilic and specific granules was the main identified biologic function of ERP. ERP was a more effective secretagogue in the untreated neutrophils and f-met-leu-phe was more effective in the cytochalasin B-treated neutrophils. Absorption of ERP from macrophage-conditioned medium removed a small amount of the chemotactic activity; however, the immunopurified peptide was not chemotactic or chemokinetic for neutrophils, and at high concentrations, it suppressed base line chemokinesis. Treatment of washed macrophages with trypsin released active ERP of approximately the same m.w. of spontaneously secreted ERP. These studies showed that human alveolar macrophages release a peptide which is a secretagogue for human neutrophils under conditions which may be encountered in the lungs during certain disease states. Proteolytic enzymes which are free in the lungs may release the peptide and lead to the secretion of neutrophil enzymes.  相似文献   

16.
在自然呼吸和窦性节律下,用浮置式玻璃微电极引导在体单个左心室肌纤维动作电位,作为兴奋的指标,以其 0相触发产生期前的试验刺激,测定有效不应期(ERP)。38只家兔的测定结果表明,在R-R间期为205—330ms的范围内,随着心率加快(R-R间期缩短),ERP减小,而 ERP/RR 间期增大,说明 ERP 与心率直接有关。并且,在较快的心率时,ERP 相对延长。通过相关与回归分析,制出了能够删除心率影响的校正公式。静脉注射酒石酸锑钾(50mg/kg)发现,在窦性和起搏节律下,酒石酸锑钾均能轻度延长 ERP(P<0.001)。窦性节律下的校正后值与起搏节律的测定结果完全一致。证明校正后值能够用来比较处理前后不同心率条件下,各种药物、离子及其它因素对ERP 的影响。 本文的校正公式虽然只适用于同种动物和方法,但此校正公式的制作原理也可以广泛应用到其它多种动物。  相似文献   

17.
Encapsulation is a major defensive reaction against foreign materials that are too large to be phagocytosed by individual hemocytes; however, the biochemical process of encapsulation is still obscure. To isolate and characterize the early-stage encapsulation-relating protein (ERP), we used the coleopteran insect, Tenebrio molitor larvae, injecting three differing kinds of bead or inserting pieces of surgical suture into the abdomen of T. molitor larvae. The resulting proteins from the injected beads or the inserted pieces of surgical suture were recovered 10 min after injection or insertion, and were analyzed on SDS/PAGE under reducing conditions. Four different proteins (86, 78, 56 and 48 kDa) were enriched compared with the crude hemolymph. Among them, we purified 56-kDa and 48-kDa ERPs to homogeneity and raised polyclonal antibodies against each protein. Immunoblotting analysis showed that the affinity-purified antibodies of the 56-kDa and 48-kDa ERPs cross-reacted with the 48-kDa and 56-kDa ERPs, respectively. Analysis of the cDNA of 56-kDa ERP consisted of 579 amino acid residues and showed a novel glutamine-rich protein. Positive clones of the 48-kDa ERP showed the same DNA sequence as 56-kDa ERP. Interestingly, the chemically determined N-terminal amino acid sequence and the three partial amino acid sequences of the 48-kDa protein were found in the 56-kDa ERP, suggesting that the 48 kDa ERP was produced by the cleavage of Arg101-Gly102 of the 56-kDa ERP by a limited proteolysis. Western blotting analysis showed that these ERPs were detected exclusively on membrane fractions of hemocytes. Also, when the early-stage encapsulated beads were coated with both the 56-kDa and 48-kDa ERP antibodies and re-injected into larvae, no further encapsulation reaction was observed. However, when the early-stage encapsulated beads were incubated with 56-kDa ERP antibody, 48-kDa ERP antibody or nonimmunized rabbit IgG and re-injected into larvae, further encapsulation did occur.  相似文献   

18.
19.
Of 144 patients with suspected pancreatic disease in whom a 75Se-selenomethionine scan was performed, endoscopic retrograde pancreatography (ERP) was successful in 108 (75%). The final diagnosis is known in 100 patients and has been compared with scan and ERP findings. A normal scan reliably indicated a normal pancreas, but the scan was falsely abnormal in 30%. ERP distinguished between carcinoma and chronic pancreatitis in 84% of cases but was falsely normal in five patients with pancreatic disease. In extrahepatic biliary disease both tests tended to give falsely abnormal results. A sequence of tests to provide a rapid and reliable assessment of pancreatic function should be a radio-isotope scan, followed by ERP if the results of the scan are abnormal, and a Lundh test if the scan is abnormal but the findings on ERP are normal.  相似文献   

20.
Nineteen-channel event-related potentials (ERPs) were studied in the GO/NOGO test in 517 healthy subjects. Multi-channel ERPs were decomposed into independent components by the method of modeling the cross-covariance structure of transient process. The research results showed that low-correlated ERP components could be obtained by this method with acceptable reliability. The identified components were associated with psychological processes, such as the attended sensory mismatch operation, decision making on the subsequent action, the action inhibition operation, and the conflict monitoring operation. In conclusion, decomposition of ERP recordings into independent components and the use of sLORETA help to localize ERP sources more accurately than the conventional ERP analysis.  相似文献   

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