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1.
Summary There are controversial reports in the literature concerning the effects of opioids on superoxide (O 2 ) formation in phagocytes, these agents being either inhibitory or stimulatory. We re-examined this issue and compared the effects of the Chemotactic peptide, N-formyl-l,-methionyl-l-leucyl-l-phenylalanine (fMet-Leu-Phe), phorbol myristate acetate (PMA), ATP, platelet activating factor (PAF), cytochalasin B (CB) and prostaglandin E1 (PGE1) with those of various opioids on O 2 formation in human neutrophils and HL-60 leukemic cells under defined experimental conditions. In the presence of CB, fMet-Leu-Phe and PAF concentration-dependently activated O 2 formation in neutrophils with EC50 values of 20 nM and 100 nM, respectively. In the absence of CB, fMet-Leu-Phe and PAF were much less effective. PAF synergistically enhanced O 2 formation induced by fMet-Leu-Phe. ATP at a concentration of 100 M and the opioids, methionine enkephalin, -endorphin, dynorphin, [d-Ala2, N-Me-Phe4, Gly5-ol]-enkephalin, [d-Ala2-d-Leu5]-enkephalin and morphine at concentrations between 10 pM to 1 M did not activate O 2 formation. ATP but not \-endorphin potentiated fMet-Leu-Phe-induced O 2 formation. O 2 formation induced by a maximally stimulatory concentration of PMA (100 ng/ml) was enhanced by fMet-Leu-Phe but was unaffected by methionine enkephalin or PGE1. PMA at a non-stimulatory concentration (2 ng/ml) potentiated the effect of fMet-Leu-Phe but did not induce responsiveness to PAF, ATP or -endorphin. PGE1 strongly inhibited fMet-Leu-Phe-induced O 2 formation, whereas morphine, methionine enkephalin and the opioid antagonist, naloxone, were without effect. In HL-60 cells differentiated with dibutyryl cAMP, fMet-Leu-Phe, PAF and ATP but not -endorphin activated O 2 formation. Our results show that O 2 formation is differentially regulated by various classes of intercellular signal molecules and that opioids do not play a role in the regulation of O 2 formation. The precise definition of the experimental conditions and control experiments with established modulators of O 2 formation are essential to evaluate the role of opioids in the regulation of this effector system.Send offprint requests to R. Seifert at the above address  相似文献   
2.
The studies presented in this article demonstrate the release of an IgE-dependent chemotactic factor for polymorphonuclear neutrophils (PMN) and eosinophils by alveolar macrophages (AMs) from normal subjects (n = 15) and allergic asthmatic patients (n = 15). A 60-minute incubation of normal AMs previously sensitized by 20% nonheated allergic sera with anti-human IgE antibody or the related allergen induced the release of a chemotactic activity (CA) for PMN and eosinophils in culture supernatants. When AMs were obtained from asthmatic patients, direct incubation with anti-IgE or the related allergen induced the same CA, whereas incubation with an unrelated allergen failed to produce CA (neutrophil CA after addition of anti-IgE, 22.5 +/- 3.5 cells per high power field; with related allergen, 15.8 +/- 3.6; with unrelated allergen, 0.7 +/- 1.8; p less than 0.0001). A partial characterization of the neutrophil chemotactic factor was carried out. Enzymatic treatment by trypsin or carboxypeptidase or by heating (56 degrees C for 3 hr) failed to abolish the neutrophil CA. After gel filtration the greater part of the neutrophil CA (80%) was recovered among low-molecular-weight components (300 to 1300 daltons). A preliminary deactivation of PMN by leukotriene B4 suppressed the CA of AM supernatants. These results indicate that IgE-dependent stimulation of AMs produces a neutrophil and eosinophil CA, present in a low-molecular-weight fraction possibly related to leukotrienes, and emphasizes the role of AMs in inflammatory lung processes during allergic asthma.  相似文献   
3.
MTEC 1分泌的趋化因子引起特定亚群胸腺细胞的定向迁移   总被引:9,自引:0,他引:9  
分析胸腺髓质上皮样细胞系MTEC1分泌的化学趋化因子对胸腺细胞亚群的趋化作用。方法以抗体加补体杀伤结合免疫磁珠及panning法,将小鼠胸腺细胞分离纯化,获得CD4+CD8+(DP),CD4-CD8-(DN),CD4+CD8-(CD4SP)及CD4-CD8+(CD8SP)四亚群细胞,用Boyden小室分析MTEC1┐SN对四群胸腺细胞的趋化作用。结果MTEC1┐SN对DP及CD4SP胸腺细胞有趋化活性(CI=6.6±1.0及6.1±1.8);对CD8SP细胞有中度趋化活性(CI=3.2±1.0);对DN趋化活性微弱(CI=1.3±0.6)。化学趋化因子MCP┐1纯品对CD4SP胸腺细胞显示强趋化活性(CI=5.6),对DN胸腺细胞则无可测出趋化活性。结论MTEC1分泌的化学趋化因子对DP,CD4SP及CD8SP胸腺细胞有显著趋化作用,对DN胸腺细胞几乎无趋化作用。提示此类化学趋化因子有趋使胸腺发育中后期阶段的细胞向胸腺髓质区迁移和定位的作用。  相似文献   
4.
目的:探讨Egr-1基因剔除对实验性胰腺炎小鼠胰腺组织中炎性相关因子表达的影响。 〖HTH〗方法:利用Egr-1基因剔除小鼠,采用大剂量雨蛙素诱导的实验性胰腺炎模型,观察Egr-1基因剔除后,胰腺组织水肿、MPO水平、血清淀粉酶水平、肺组织MPO水平的改变。并利用定量PCR的方法,检测胰腺组织中炎症相关因子组织因子(TF)、纤维蛋白溶酶原激活因子抑制因子(PAI-1)、单核细胞趋化吸引蛋白1(MCP-1)、Gro-1、IL-6和细胞间黏附分子-1(ICAM-1) mRNA的表达。 〖HTH〗结果:Egr-1基因剔除小鼠胰腺组织水肿明显轻于野生型,但组织MPO水平与血清淀粉酶与野生型组间相比无明显差异;肺组织MPO水平明显低于野生型。定量PCR检测结果表明, Egr-1基因剔除组,胰腺组织中TF、PAI-1,以及MCP-1、ICAM-1和IL-6 mRNA的表达,明显少于野生型组。 〖HTH〗结论:Egr-1基因剔除可明显减轻急性胰腺炎的严重程度,其作用可能通过减少胰腺组织中TF、PAI-1,以及MCP-1、ICAM-1和IL-6的表达而实现。  相似文献   
5.
Wistar大鼠实验性变态反应性脑脊髓炎模型的制备   总被引:3,自引:0,他引:3  
目的 探讨Wistar大鼠诱导实验性变态反应脑脊髓炎 (EAE)动物模型 ,检测EAE中起关键趋化作用的巨噬细胞趋化因子 - 1(MCP- 1)的表达。方法 采用免疫诱导方法制备EAE模型并苏木素 伊红 (HE)染色 ,同时用原位杂交法检测EAE大鼠MCP -1的表达。结果 免疫后 12~ 17d ,发病鼠出现EAE临床症状 ,HE染色 ,光镜下可见血管周围炎性浸润 ,MCP- 1的表达明显增加。结论 Wistar大鼠成功的诱导实验性变态反应脑脊髓炎模型是可信、可用的。  相似文献   
6.
钟万锷  周国雄  丁晓凌  黄华 《胃肠病学》2008,13(12):728-732
背景:溃疡性结肠炎(UC)的病因和发病机制尚不完全明确,趋化因子异常可能在其发生、发展中起重要作用。目的:研究趋化因子CCL20及其受体CCR6在葡聚糖硫酸钠(DSS)诱导的实验性结肠炎小鼠结肠黏膜中的表达以及CCL20与CCR6的相关性,探讨两者在结肠炎发病机制中的作用。方法:30只雌性BALB/c小鼠分为对照组和模型组。模型组小鼠自由饮用5%DSS溶液7d,建立实验性结肠炎模型;对照组小鼠自由饮用蒸馏水7d。第8d处死小鼠,观察疾病活动指数(DAI)、结肠组织学评分。以逆转录聚合酶链反应(RT.PCR)检测小鼠结肠黏膜CCL20、CCR6mRNA表达,以免疫组化和蛋白质印迹法检测结肠黏膜CCL20、CCR6蛋白表达,并分析CCL20与CCR6的相关性。结果:模型组DAI和结肠组织学评分均显著高于对照组(P〈0.01);CCL20、CCR6mRNA和蛋白表达显著高于对照组(P〈0.01),且与结肠炎症程度呈正相关。CCL20mRNA表达与CCR6mRNA表达有明显相关性(r=0.763.P=0.000071)。结论:CCL20和CCR6表达参与了结肠炎的发生和发展,两者相互作用可能在结肠炎局部结肠组织破坏和病理变化中起重要作用,有望成为UC的潜在治疗靶点。  相似文献   
7.
目的研究CXCL16的表达对小鼠免疫性肝损伤中的作用及意义。方法建立卡介苗和内毒素诱导的小鼠肝损伤模型,通过实时定量聚合酶链反应和免疫组织化学分析CXCL16在肝组织中的表达变化,根据肝脏病理变化和免疫组织化学结果分析,比较CXCL16的表达水平和肝脏损伤程度的关系。从模型中各个时间点的肝损伤组织中分离浸润单核细胞,计算浸润的细胞数量变化,并进一步分析其中主要的CD4和CD8T淋巴细胞亚群的数量变化,研究CXCL16在肝脏炎症和损伤中的作用和意义。结果成功复制了小鼠免疫性肝损伤模型,发现在肝脏炎症和损伤中CXCL16表达水平显著上调,CXCL16的表达水平与肝脏损伤程度密切相关,肝脏组织浸润的单核细胞数晕明显增加,淋巴细胞尤其是CD4 、CD8 T淋巴细胞数量也有明显的增加。结论小鼠肝脏损伤过程中CXCL16表达水平的增加与肝损伤程度密切相关,CXCL16趋化淋巴细胞浸润可能是导致肝脏损伤的重要机制之。  相似文献   
8.
本文以培养的兔主动脉平滑肌细胞条件培养基作为趋化因子的来源,用改良的Boyden小室微孔滤膜法进行单核细胞的迁移试验,并观察戊脉胺和细胞外Ca2+对其影响。用Fura-2检测单核细胞胞液游离钙浓度,并观察上述条件培养基及戊脉胺对其影响。结果表明,该条件培养基对单核细胞有明显趋化作用并被戊脉胺所抑制;它也能明显地升高单核细胞胞液游离钙浓度,并被戊脉胺所抑制。细胞外Ca2+也能影响单核细胞的迁移。以上结果提示,单核细胞迁移对细胞内、外Ca2+均有依赖性。  相似文献   
9.

Background

Extracorporeal shock wave therapy (ESWT) has been demonstrated to have the angiogenic effect on ischemic tissue. We hypothesize that ESWT exerts the proangiogenesis effect with an energy density–dependent mode on the target cells.

Materials and methods

Endothelial progenitor cells (EPCs) of rats were obtained by cultivation of bone marrow–derived mononuclear cells. EPCs were divided into five groups of different energy densities, and each group was furthermore subdivided into four groups of different shock numbers. Thus, there were 20 subgroups in total. The expressions of angiogenic factors, apoptotic factors, inflammation mediators, and chemotactic factors were examined, and the proliferation activity was measured after ESWT.

Results

When EPCs were treated with low-energy (0.04–0.13 mJ/mm2) shock wave, the expressions of endothelial nitric oxide synthase, angiopoietin (Ang) 1, Ang-2, and B-cell lymphoma 2 increased and those of interleukin 6, fibroblast growth factor 2, C-X-C chemokine receptor type 4, vascular endothelial growth factor a, Bcl-2-associated X protein, and caspase 3 decreased. stromal cell-derived factor 1 changed without statistical significance. When cells were treated with high-energy (0.16 mJ/mm2) shock wave, most of the expressions of cytokines declined except the apoptotic factors and fibroblast growth factor 2, and cells lead to apoptosis. The proliferation activity and the ratio of Ang-1/Ang-2 reached their peak values, when cells were treated with ESWT with the intensity ranging from 0.10–0.13 mJ/mm2 and shock number ranging from 200–300 impulses. Meanwhile, a minimal value of the ratio of Bax/Bcl-2 was observed.

Conclusions

There is a dose–effect relationship in ESWT. The shock intensity ranging from 0.10–0.13 mJ/mm2 and shock number ranging from 200–300 impulses were the optimal parameters for ESWT to treat cells in vitro.  相似文献   
10.
The hornet possesses highly toxic venom, which is rich in toxin, enzymes and biologically active peptides. Many bioactive substances were identified from wasp venom. Two families of antimicrobial peptides were purified and characterized from the venom of the wasp, Vespamagnifica (Smith). The primary structures of these peptides are homologous to those of chemotactic peptides and mastoparans isolated from other vespid venoms. They also share similarity to temporins which are amphibian antimicrobial peptides identified from the skin of the frog, Ranaboylii. These peptides show antimicrobial activities against bacteria and fungi. However, they show little hemolytic activity against human blood red cells.  相似文献   
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