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71.
Yu GF  Huang Q  Dai WM  Jie YQ  Fan XF  Wu A  Lv Y  Li YP  Yan XJ 《Peptides》2012,33(1):164-169
High plasma copeptin level has been associated with one-month mortality after traumatic brain injury. However, not much is known regarding its relation with long-term outcome. Thus, we investigated the ability of copeptin to predict 1-year outcome in patients with traumatic brain injury. One hundred and six healthy controls and 106 patients with acute severe traumatic brain injury were included. Plasma samples were obtained on admission. Its concentration was measured by enzyme-linked immunosorbent assay. Forty-eight patients (45.3%) suffered from unfavorable outcome (Glasgow Outcome Scale score of 1-3) and 31 patients (29.2%) died in 1 year after traumatic brain injury. Upon admission, plasma copeptin level in patients was substantially higher than that in healthy controls. A forward stepwise logistic regression selected plasma copeptin level as an independent predictor for 1-year unfavorable outcome and mortality of patients. A receiver operating characteristic curve analysis showed plasma copeptin level predicted 1-year unfavorable outcome and mortality obviously. The predictive value of the copeptin concentration was thus similar to that of Glasgow Coma Scale score for the prediction of unfavorable outcome and mortality after 1 year. In a combined logistic-regression model, copeptin improved the area under curve of Glasgow Coma Scale score for the prediction of unfavorable outcome and mortality after 1 year, but the differences were not significant. Thus, copeptin level is a useful, complementary tool to predict functional outcome and mortality 1 year after traumatic brain injury.  相似文献   
72.
Early during Gram-negative sepsis, excessive release of pro-inflammatory cytokines can cause septic shock that is often followed by a state of immune paralysis characterized by the failure to mount adaptive immunity towards secondary microbial infections. Especially, the early mechanisms responsible for such immune hypo-responsiveness are unclear. Here, we show that TLR4 is the key immune sensing receptor to initiate paralysis of T-cell immunity after bacterial sepsis. Downstream of TLR4, signalling through TRIF but not MyD88 impaired the development of specific T-cell immunity against secondary infections. We identified type I interferon (IFN) released from splenic macrophages as the critical factor causing T-cell immune paralysis. Early during sepsis, type I IFN acted selectively on dendritic cells (DCs) by impairing antigen presentation and secretion of pro-inflammatory cytokines. Our results reveal a novel immune regulatory role for type I IFN in the initiation of septic immune paralysis, which is distinct from its well-known immune stimulatory effects. Moreover, we identify potential molecular targets for therapeutic intervention to overcome impairment of T-cell immunity after sepsis.  相似文献   
73.
目的观察叶酸联合成体神经干细胞对创伤性脑损伤大鼠的治疗作用,探讨其可能作用机制。方法 120只Wistar大鼠随机分为6组,正常组,模型组,假手术组,叶酸注射组,成体神经干细胞移植组,成体神经干细胞移植+叶酸注射组。倒置显微镜下观察神经干细胞形态学变化;流式细胞仪检测神经干细胞表面标记物CD105、CD45、CD44、CD29的表达;免疫荧光法检测神经元特异性烯醇酶(NSE成熟神经元的特异性标志)、胶质纤维酸性蛋白(GFAP胶质细胞的标记物)的表达;平衡木实验检测大鼠运动协调与整和能力;Morris水迷宫实验测试各组大鼠的学习记忆能力;HE染色及Brdu免疫组化实验观察脑组织形态学变化;酶联免疫吸附试验检测大鼠脑组中脑源性神经生长因子(BDNF)、神经生长因子(NGF)的表达;蛋白质印迹法检测脑组织中凋亡相关蛋白BCL-2、Bax、Caspase-3的表达。结果分离所得细胞能在体外传代培养,流式细胞仪检测发现细胞阳性表达CD44、CD29,阴性表达CD105、CD45,细胞经胎牛血清诱导分化后能形成NSE或GFAP阳性细胞。实验表明,叶酸与成体神经干细胞干预创伤性脑损伤大鼠模型后能显著改善其行为学变化,减轻脑组织的炎症反应,恢复受损神经细胞,增加脑组织内BDNF、NGF的含量,上调BCL-2的表达,下调Bax、Caspase-3的表达。结论叶酸联合成体神经干细胞干预创伤性脑损伤大鼠能显著改善中枢神经功能,对维持神经元微环境稳态具有重要的作用。  相似文献   
74.
Teng QY  Zhou JY  Wu JJ  Guo JQ  Shen HG 《FEBS letters》2006,580(17):4274-4281
To identify chicken IL-2R alpha chain (chCD25), the cDNA of chCD25 was cloned and mapped onto chicken chromosome 1. The polyclonal and monoclonal antibodies raised from the recombinant chCD25 specifically bound to the cell surface of splenic mononuclear cells (SMC) and inhibited chicken IL-2-dependent proliferation of T cells. Flow cytometry analysis revealed that chCD25 molecules could be expressed on the surface of monocytes/macrophages, thrombocytes, CD4+ and CD8+ cells as well as tissue cells. Importantly, the CD4+CD25+ and CD8+CD25+ cells were upregulated dramatically in chickens infected with H9N2 avian influenza virus. These results confirm that the cloned cDNA is the nucleotide sequence of chicken IL-2R, and suggest that chicken CD4+CD25+ and CD8+CD25+ cells may play an important role in immune responses induced by H9N2 virus, and the monoclonal antibodies to chCD25 may be useful for investigating biological functions of chicken regulatory T cells.  相似文献   
75.
76.
目的创建一种操作简单、经济实用的动脉粥样硬化(AS)破裂斑块及血栓动物模型。方法21只雄性纯种新西兰白兔随机分为两组:液氮冻伤+高脂喂养组(A组=11只)和高脂喂养组(B组=10只)。A组实施右颈总动脉内膜液氮冻伤术结合高脂饲料喂养,B组单纯给予高脂饲料喂养。8周末以液氮激发斑块破裂,激发前后分别采血检测血脂、hsC-RP、MMP-9及PAI-1水平;激发48h后处死所有动物,取出右颈总动脉作HE染色及免疫组化染色等,光镜及电镜观察破裂斑块及血栓形成情况。结果8周后兔血脂水平明显升高;激发后血浆hsC-RP、MMP-9及PAI-1均明显升高;所有A组兔子的右颈总动脉均可见AS破裂斑块及血栓形成,而B组兔子未见斑块或血栓形成;所建立的破裂斑块在组织结构、细胞构成、生长特征和脂质沉积方面与人类斑块相似。结论液氮冻伤术能简便、快速、高效地建立AS破裂斑块及血栓模型,从而为研究人类AS破裂斑块及血栓形成的机理和药物干预治疗提供了一种新型动物模型。  相似文献   
77.
小型猪动脉粥样硬化斑块稳定性模型研究   总被引:10,自引:0,他引:10  
目前已有的动物模型在研究动脉粥样硬化斑块破裂、破裂的可控性及量化研究方面均不能满足研究的需要.为了建立类似于人类动脉粥样硬化病变的斑块模型,体外研究斑块稳定性,应用传统的高脂高胆固醇膳食诱导建立了小型猪动脉粥样硬化模型,并从血脂水平和斑块病理形态学特征方面加以了证实.该模型中斑块与人类成熟斑块的高度相似性使其成为研究斑块稳定性和斑块破裂的较好模型.从量化比较这一出发点着手,建立了一个体外可控可量化诱导斑块破裂模型,方法简单易行,是一个较好的量化研究斑块破裂和破裂相关因素间关系的实验模型.  相似文献   
78.
Necrotic neuronal death is recently known to be mediated by the calpain-cathepsin cascade from simpler organisms to primates. The main event of this cascade is calpain-mediated lysosomal rupture and the resultant release of lysosomal cathepsins into the cytoplasm. However, the in-vivo substrate of calpain for inducing lysosomal destabilization still remains completely unknown. The recent proteomics data using the post-ischemic hippocampal CA1 tissues and glaucoma-suffered retina from the primates suggested that heat shock protein (Hsp) 70.1 might be the in-vivo substrate of activated μ-calpain at the lysosomal membrane of neurons. Hsp70.1 is known to stabilize lysosomal membrane by recycling damaged proteins and protect cells from oxidative stresses. Here, we studied the molecular interaction between activated μ-calpain and the lysosomal Hsp70.1 in the monkey hippocampal CA1 neurons after the ischemia-reperfusion insult. Immunofluorescence histochemistry showed a colocalization of the activated μ-calpain and upregulated Hsp70.1 at the lysosomal membrane of the post-ischemic CA1 neurons. In-vitro cleavage assay of hippocampal Hsp70.1 by Western blotting demonstrated that Hsp70.1 in the CA1 tissue is an in-vivo substrate of activated μ-calpain, and that carbonylated Hsp70.1 in the CA1 tissue by artificial oxidative stressors such as hydroxynonenal (HNE) or hydrogen peroxide is much more vulnerable to the calpain cleavage. These data altogether suggested that Hsp70.1 can become a target of the carbonylation by HNE, and Hsp70.1 is a modulator of calpain-mediated lysosomal rupture/permeabilization after the ischemia-reperfusion injury.  相似文献   
79.
80.
The purpose of this study was to describe kinematic and kinetic differences between a group of ACL deficient subjects who were grouped according to functional ability. Sixteen patients with complete ACL rupture were studied; eight subjects had instability with activities of daily living (non-copers) and eight subjects had returned to all pre-injury activity without limitation (copers). Three-dimensional joint kinematics and kinetics were collected from the knee and ankle during walking, jogging and going up and over a step. Results showed that both groups mitigated the force with which they contacted the floor but non-copers consistently demonstrated less knee flexion in the involved limb. The copers used joint kinematics similar to those of their uninvolved knees and similar to knee motions reported in uninjured subjects. The reduced knee motion in the involved knee of the non-copers did not correlate directly with quadriceps femoris muscle weakness.

The data suggest that the non-copers utilize a stabilization strategy which stiffens the knee joint which not only is unsuccessful but may lead to excessive joint contact forces which have the potential to damage articular structures. The copers use a strategy which permits normal knee kinematics and bodes well for joint integrity.  相似文献   

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