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71.
Wang W Liu X Zhao J Zhao B Zhang S Miao J 《Bioorganic & medicinal chemistry letters》2007,17(2):482-485
To understand the effects of a novel butyrolactone derivative, 3-benzyl-5-((2-nitrophenoxy) methyl)-dihydrofuran-2(3H)-one (3BDO), on the apoptosis of vascular endothelial cells (VECs), we exposed 3BDO (20-60 microg/ml) to VECs deprived of serum and FGF-2 for 24 and 48 h, respectively. The results showed that 3BDO (20-60 microg/ml) increased VEC viability and inhibited VEC apoptosis induced by deprivation of serum and FGF-2 in a very weak dose-dependent manner. During this process, integrin beta4 expression was depressed, but the level of reactive oxygen species (ROS) was not changed. The data suggested that 3BDO (20-60 microg/ml) could inhibit VEC apoptosis and suppress integrin beta4 expression, but it could not depress the ROS level induced by deprivation of serum and FGF-2. 相似文献
72.
Zhiping Song Weiyue Zhu Jun Rong Xian Xu Jiakuan Chen Bao-Rong Lu 《Evolutionary ecology》2006,20(6):501-522
Crop-to-wild introgression may play an important role in evolution of wild species. Asian cultivated rice (Oryza sativa L.) is of a particular concern because of its cross-compatibility with the wild ancestor, O. rufipogon Griff. The distribution of cultivated rice and O. rufipogon populations is extensively sympatric, particularly in Asia where many wild populations are surrounded by rice fields. Consequently, gene flow from cultivated rice may have a potential to alter genetic composition of wild rice populations in close proximity. In this study, we estimated introgression of cultivated rice with O. rufipogon based on analyses of 139 rice varieties (86 indica and 53 japonica ecotypes) and 336 wild individuals from 11 O. rufipogon populations in China. DNA fingerprinting based on 17 selected rice simple sequence repeat (SSR) primer pairs was adopted to measure allelic frequencies in rice varieties and O. rufipogon samples, and to estimate genetic associations between wild and cultivated rice through cluster analysis. We detected consanguinity of cultivated rice in O. rufipogon populations according to the admixture model of the STRUCTURE program. The analyses showedz that four wild rice populations, DX-P1, DX-P2, GZ-P2, and HL-P, contained some rare alleles that were commonly found in the rice varieties examined. In addition, the four wild rice populations that scattered among the rice varieties in the cluster analysis showed a closer affinity to the cultivars than the other wild populations. This finding supports the contention of substantial gene flow from crop to wild species when these species occur close to each other. The introgressive populations had slightly higher genetic diversity than those that were isolated from rice. Crop-to-wild introgression may have accumulative impacts on genetic variations in wild populations, leading to significant differentiation in wild species. Therefore, effective measure should be taken to avoid considerable introgression from cultivated rice, which may influence the effective in-situ conservation of wild rice species. 相似文献
73.
Li H Jin G Qin J Tian M Shi J Yang W Tan X Zhang X Zou L 《Histochemistry and cell biology》2011,136(5):515-526
During the central nervous system (CNS) development, radial glia cells (RGCs) play at least two essential roles, they contribute
to neuronal production and the subsequent guidance of neuronal migration, whereas its precise distribution and contribution
to cerebral cortex remains less understood. In this research, we used Vimentin as an astroglial marker and Sox2 as a neural
progenitor marker to identify and investigate RGCs in rat cerebral cortex at embryonic day (E) 16.5. We found that the Sox2+
progenitor cells localized in the germinal zone (GZ) of E16.5 cerebral cortex, ~95% Sox2+ cells co-localized with Vimentin+
or Nestin+ radial processes which extended to the pial surface across the cortical plate (CP). In vitro, we obtained RG-like
cells from E16.5 cerebral cortex on adherent conditions, these Sox2+ Radial glia (RG)-like cells shared some properties with
RGCs in vivo, and these Sox2+ RG-like cells could differentiate into astrocytes, oligodendrocytes and presented the radial
glia—neuron lineage differentiation ability. Taken together, we identified and investigated some characterizations and properties
of Sox2+ RGCs derived from E16.5 cerebral cortex, we suggested that the embryonic Sox2+ progenitor cells which located in
the cortical GZ were mainly composed of Sox2+ RGCs, and the cortex-derived Sox2+ RG-like cells displayed the radial glia—neuron
lineage differentiation ability as neuronal progenitors in vitro. 相似文献
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75.
Zhong Q. WangDavid Ribnicky Xian H. ZhangAamir Zuberi Ilya RaskinYongmei Yu William T. Cefalu 《The Journal of nutritional biochemistry》2011,22(1):71-78
An ethanolic extract of Artemisia dracunculus L. (PMI 5011) has been observed to decrease glucose and insulin levels in animal models, but the cellular mechanisms by which insulin action is enhanced in vivo are not precisely known. In this study, we evaluated the effects of PMI 5011 to modulate gene expression and cellular signaling through the insulin receptor in skeletal muscle of KK-Ay mice. Eighteen male KK-Ay mice were randomized to a diet (w/w) mixed with PMI 5011 (1%) or diet alone for 8 weeks. Food intake, adiposity, glucose and insulin were assessed over the study, and at study completion, vastus lateralis muscle was obtained to assess insulin signaling parameters and gene expression. Animals randomized to PMI 5011 were shown to have enhanced insulin sensitivity and increased insulin receptor signaling, i.e., IRS-associated PI-3 kinase activity, Akt-1 activity and Akt phosphorylation, in skeletal muscle when compared to control animals (P<.01, P<.01 and P<.001, respectively). Gene expression for insulin signaling proteins, i.e., IRS-1, PI-3 kinase and Glut-4, was not increased, although a relative increase in protein abundance was noted with PMI 5011 treatment. Gene expression for specific ubiquitin proteins and specific 20S proteasome activity, in addition to skeletal muscle phosphatase activity, i.e., PTP1B activity, was significantly decreased in mice randomized to PMI 5011 relative to control. Thus, the data demonstrate that PMI 5011 increases insulin sensitivity and enhances insulin receptor signaling in an animal model of insulin resistance. PMI 5011 may modulate skeletal muscle protein degradation and phosphatase activity as a possible mode of action. 相似文献
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79.
目的:探讨冠心病(CAD)患者血清C-反应蛋白(CRP)的变化及其临床意义.方法:运用全自动生化分析仪检测97例CAD患者和28例对照组人群的血清CRP,将CAD患者进一步分为稳定性心绞痛组(SAP)、不稳定心绞痛(UAP)、心肌梗死组(AMI)三组.另外,将97例CAD惠者分为1支病变组、2支病变组和3支病变组.所有研究对象均行选择性冠状动脉造影检查.结果:(1)与对照组比较,CAD患者血清CRP显著升高(P<0.05);(2)与对照组比较,SAP组、UAP组和AMI组患者血清CRP均显著升高(P<0.05);与SAP组比较,UAP组和AMI组患者血清CRP亦显著升高(P<0.05);(3)与对照组比较,1支病变组、2支病变组和3支病变组患者血清CRP均显著升高(P<0.05);与1支病变组比较,2支病变组和3支病变组患者血清CRP亦显著升高(P<0.05);与2支病变组比较,3支病变组患者血清CRP亦显著升高(P<0.05).结论:(1)CRP可能与CAD有关;(2)CRP异常升高可能反映冠状动脉斑块的不稳定和CAD的严重程度. 相似文献
80.
Weiwei Kong Chuang Li Qiaofang Qi Jiahui Shen Kaiwen Chang 《Cell biology international》2020,44(1):177-188
Cardamonin (CD), a naturally occurring chalcone isolated from large black cardamom, was previously reported to suppress the proliferation of breast cancer cells. However, its precise molecular anti‐tumor mechanisms have not been well elucidated. In this study, we found that CD markedly inhibited the proliferation of MDA‐MB 231 and MCF‐7 breast cancer cells through the induction of G2/M arrest and apoptosis. Reactive oxygen species (ROS) plays a pivotal role in the inhibition of CD‐induced cell proliferation. Treatment with N‐acetyl‐cysteine (NAC), an ROS scavenger, blocked CD‐induced G2/M arrest and apoptosis in this study. Quenching of ROS by overexpression of catalase also blocked CD‐induced cell cycle arrest and apoptosis. We showed that CD enhanced the expression and nuclear translocation of Forkhead box O3 (FOXO3a) via upstream c‐Jun N‐terminal kinase, inducing the expression of FOXO3a and its target genes, including p21, p27, and Bim. This process led to the reduction of cyclin D1 and enhancement of activated caspase‐3 expression. The addition of NAC markedly reversed these effects, knockdown of FOXO3a using small interfering RNA also decreased CD‐induced G2/M arrest and apoptosis. In vivo, CD efficiently suppressed the growth of MDA‐MB 231 breast cancer xenograft tumors. Taken together, our data provide a molecular mechanistic rationale for CD‐induced cell cycle arrest and apoptosis in breast cancer cells. 相似文献