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Tao Wang Shi-Wei Wang Yue Zhang Xue-Fei Wu Yan Peng Zhen Cao Bi-Ying Ge Xi Wang Qiong Wu Jin-Tao Lin Wan-Qin Zhang Shao Li Jie Zhao 《PloS one》2014,9(10)
Scorpion venom heat-resistant peptide (SVHRP) is a component purified from Buthus martensii Karsch scorpion venom. Although scorpions and their venom have been used in Traditional Chinese Medicine (TCM) to treat chronic neurological disorders, the underlying mechanisms of these treatments remain unknown. We applied SVHRP in vitro and in vivo to understand its effects on the neurogenesis and maturation of adult immature neurons and explore associated molecular mechanisms. SVHRP administration increased the number of 5-bromo-2’-dexoxyuridine (BrdU)-positive cells, BrdU- positive/neuron-specific nuclear protein (NeuN)-positive neurons, and polysialylated-neural cell adhesion molecule (PSA-NCAM)-positive immature neurons in the subventricular zone (SVZ) and subgranular zone (SGZ) of hippocampus. Furthermore immature neurons incubated with SVHRP-pretreated astrocyte-conditioned medium exhibited significantly increased neurite length compared with those incubated with normal astrocyte-conditioned medium. This neurotrophic effect was further confirmed in vivo by detecting an increased average single area and whole area of immature neurons in the SGZ, SVZ and olfactory bulb (OB) in the adult mouse brain. In contrast to normal astrocyte-conditioned medium, higher concentrations of brain-derived neurotrophic factor (BDNF) but not nerve growth factor (NGF) or glial cell line-derived neurotrophic factor (GDNF) was detected in the conditioned medium of SVHRP-pretreated astrocytes, and blocking BDNF using anti-BDNF antibodies eliminated these SVHRP-dependent neurotrophic effects. In SVHRP treated mouse brain, more glial fibrillary acidic protein (GFAP)-positive cells were detected. Furthermore, immunohistochemistry revealed increased numbers of GFAP/BDNF double-positive cells, which agrees with the observed changes in the culture system. This paper describes novel effects of scorpion venom-originated peptide on the stem cells and suggests the potential therapeutic values of SVHRP. 相似文献
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胚胎性癌细胞(简称EC细胞)作为一类肿瘤(畸胎瘤)的干细胞近年受到广泛的重视,从胚胎学、肿瘤学和分子生物学等许多学科领域都应用它作为实验材料,离体诱导分化研究是其中的一个方面。B 7-2 EC细胞是我们从129品系小鼠的自发睾丸畸胎瘤中分离克隆得到的一株多能EC细胞,它在同种同基因小鼠 相似文献
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控灌对小麦植株体内激素含量与籽粒灌浆速率的影响 总被引:5,自引:0,他引:5
利用防雨棚研究了控灌对小麦植株体内激素含量与籽粒不乐速率的影响。结果表明:随控水加重,小麦旗叶、根系和籽粒中ABA含量迅速达到高峰,然后快速降低;控水愈重,i-PAs峰值和籽粒灌浆速率峰值出现愈早,尔后下降,从而加速了植株衰老进程,导致产量降低。籽粒灌浆速率变化与旗叶,根主籽粒中激素含量变化呈极显著相关,且上述性状在相对含水量60%处理下与80%(对照)相比无显著差异,从而为小麦节水栽培提供了依据 相似文献
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Fengyong Yang Zhen Liu Yajing Wang Zhaoxin Li Haichu Yu Qixin Wang 《Cell biochemistry and biophysics》2014,70(3):1683-1686
The aim of the study was to evaluate the clinical efficacy of hydrogen sulfide (H2S) treatment on the endothelin-induced cardiac hypertrophy. Sixty-four adult male rats, weighing from 180 to 200 g, were randomly divided into four groups: ten in normal group, ten in sham group, 44 in model group established by inducing the myocardial hypertrophy with endothelin. The myocardial hypertrophy model rats were randomly divided into two groups: 22 in the simple myocardial hypertrophy model group and 22 in the H2S treatment group. Rats in normal group were given 2 ml pure water by gavage per day, those in the sham group and simple cardiac hypertrophy model group were given 2 ml of saline by gavage per day, and rats in the pure cardiac hypertrophy with H2S treatment were given intraperitoneal injections of 2 ml NaHS saline per day for a period of 4 weeks. Left ventricular mass index, myocyte hypertrophy, volume fraction of myocardial interstitial collagen, myocardial hydroxyproline content and other indicators of cardiac hypertrophy were observed after 4 weeks. (1) There were significant differences on the ventricular mass between the treatment group and the cardiac hypertrophy group: The left ventricular mass decreased 21.4 % and the left ventricular mass index decreased 5.97 % (P < 0.05; (2) the smallest cardiomyocytes diameter and cardiomyocytes cross-sectional area decreased 12.5 and 10.8 %, respectively (P < 0.05) in the treatment group compared to the cardiac hypertrophy group; (3) the volume fraction of myocardial interstitial collagen and the myocardial hydroxyproline content decreased 22.3 and 31.3 % in treatment group compared with the cardiac hypertrophy group, respectively (P < 0.05). H2S had a good clinical efficacy in reducing left ventricular mass fraction and myocardial collagen levels, improving myocardial hypertrophy and decrease myocardial fibrosis. It is worthy for further clinical studies. 相似文献
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Hai‐Yan Liu Huhe Chao Zhen‐Kun Liu Hong‐Fei Xia Zhihui Song Ying Yang Jing‐Pian Peng 《Journal of cellular and molecular medicine》2014,18(3):455-467
Cytochrome P450 26A1 (cyp26a1) is expressed in the mouse uterus during peri‐implantation. The repression of this protein is closely associated with a reduction in implantation sites, suggesting a specific role for cyp26a1 in pregnancy and prompting questions concerning how a metabolic enzyme can generate this distinct outcome. To explore the effective downstream targets of cyp26a1 and confirm if its role in peri‐implantation depends on its metabolic substrate RA (retinoic acid), we characterized the changes in the peripheral blood, spleen and uterine implantation sites using the cyp26a1 gene vaccine constructed before. Flow cytometry results showed a significant increase in CD4+RORγt+ Th17 cells in both the peripheral blood and spleen in the experimental group. The expression of RORγt and IL‐17 presented the Th17 cells reduction in uterus followed by the suppression of cyp26a1 expression. For greater certainty, cyp26a1 antibody blocking model and RNA interference model were constructed to determine the precise target immune cell group. High performance liquid chromatography results showed a significant increase in uterine at‐RA followed by the immunization of cyp26a1 gene vaccine. Both the ascertain by measuring RARα protein levels in peri‐implantation uterus after gene vaccine immunization and researches using the specific agonist and antagonist against RARα suggested that RARα may be the main RA receptor for signal transduction. These results provided more evidence for the signal messenger role of RA in cyp26a1 regulation from the other side. Here, we showed that the cyp26a1‐regulated Th17 cells are dependent on at‐RA signalling, which is delivered through RARα in mouse peri‐implantation. 相似文献
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