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971.
Mesenchymal stem cells (MSCs) transplantation has emerged as a potential therapeutic approach for Alzheimer's disease (AD). However, the poor proliferation capacity and low survival rate of engrafted MSCs in the hostile microenvironment of AD limit their therapeutic efficiency. Lin28B is a conserved RNA-binding protein associated with cell self-renewal and survival. The purpose of the present study was to explore whether lin28B might influence the functions of implanted MSCs and strengthen their neuroprotective potential in AD. A gain-of-function assay was used to upregulate lin28B expression in MSCs by lentiviral transfection. Our in vitro results indicated that lin28B promoted MSCs proliferation and migration, and protected MSCs against Aβ1–42-induced cell death by upregulating insulin-like growth factor-2 (IGF-2). Blockage of IGF-2 partially abrogated the above effects of lin28B. After intracerebroventricular injection into amyloid precursor protein/presenilin 1 mice, implanted MSCs were monitored using bioluminescence imaging. We observed that administration of MSCs transfected with lin28B significantly stimulated their proliferation and prolonged cell retention after delivery. Moreover, administration of the transfected MSCs markedly mitigated cognitive deficits, promoted amyloid plaque clearance, decreased the activation of microglia, and reduced neuronal cell death. The data above confirmed our hypothesis that lin28B is a crucial modulator determining the fate of transplanted MSCs by regulating IGF-2-associated pathways and thereby enhancing their protective effects against AD.  相似文献   
972.
Seed shattering refers to the phenomenon in which the pods split along the abdominal and back sutures before the crop is received, so that the seeds are spread. Seed shattering is vital to the reproduction of their offspring in wild plants, but it is also the main cause of crop yield loss reason. Pod-explosion resistance is a complex process of physical and physiological and biochemical reactions. Soybean seed shattering phenomenon is widespread, which severely restricts the development of soybean industry. Seed shattering (pod cracking or fruit dropping) is essential for the reproduction of its offspring in wild plants, but it is also the main cause of crop yield loss. This article analyzes the morphology and structure of pods related to seed shattering from the morphology of pods. On the basis of the regularity of the occurrence of seed shattering and the summary of phenotypic index identification methods, physiologically introduced the regulation mechanism of key enzymes and endogenous hormones on seed shattering. The localization, labeling and cloning of seed shattering genes are introduced in molecular biology. The study focused on reviewing the latest advances in the research on soybean seed shattering characteristics, and discussed with the research results of related crops. Finally, the research and application of soybean seed shattering resistance were prospected for several aspects.  相似文献   
973.
974.
Coxsackievirus A10 (CV-A10) is one of the etiological agents associated with hand, foot and mouth disease (HFMD) and also causes a variety of illnesses in humans, including pneumonia, and myocarditis. Different people, particularly young children, may have different immunological responses to infection. Current CV-A10 infection animal models provide only a rudimentary understanding of the pathogenesis and effects of this virus. The characteristics of CV-A10 infection, replication, and shedding in humans remain unknown. In this study, rhesus macaques were infected by CV-A10 via respiratory or digestive route to mimic the HFMD in humans. The clinical symptoms, viral shedding, inflammatory response and pathologic changes were investigated in acute infection (1–11 day post infection) and recovery period (12–180 day post infection). All infected rhesus macaques during acute infection showed obvious viremia and clinical symptoms which were comparable to those observed in humans. Substantial inflammatory pathological damages were observed in multi-organs, including the lung, heart, liver, and kidney. During the acute period, all rhesus macaques displayed clinical signs, viral shedding, normalization of serum cytokines, and increased serum neutralizing antibodies, whereas inflammatory factors caused some animals to develop severe hyperglycemia during the recovery period. In addition, there were no significant differences between respiratory and digestive tract infected animals. Overall, all data presented suggest that the rhesus macaques provide the first non-human primate animal model for investigating CV-A10 pathophysiology and assessing the development of potential human therapies.  相似文献   
975.
Xue  Bai  Wang  Ping  Yu  Wenzhen  Feng  Jing  Li  Jie  Zhao  Rulian  Yang  Zhenglin  Yan  Xiyun  Duan  Hongxia 《中国科学:生命科学英文版》2022,65(6):1157-1170
Science China Life Sciences - Blood vessel dysfunction causes several retinal diseases, including diabetic retinopathy, familial exudative vitreoretinopathy, macular degeneration and choroidal...  相似文献   
976.
目的探讨替米沙坦(TM)调控miR-495-3p/心肌细胞增强因子2A (MEF2A)通路对缺氧诱导PC12细胞损伤的影响和机制。 方法将PC12细胞进行正常培养(对照),缺氧(缺氧24 h),缺氧+ 0.1、1、10 μg/mL TM、缺氧+ miR-NC (转染miR-NC),缺氧+miR-495-3p (转染miR-495-3p模拟物),缺氧+TM+anti-miR-NC (转染anti-miR-NC,10 μg/mL TM)和缺氧+ TM+anti-miR-495-3p (转染anti-miR-495-3p,10 μg/mL TM)处理。酶联免疫吸附实验(ELISA)检测乳酸脱氢酶(LDH)漏出量和超氧化物歧化酶(SOD)的活性,流式细胞术检测细胞凋亡,实时荧光定量PCR (RT-qPCR)和Western blot检测miR-495-3p、心肌细胞增强因子2A (MEF2A)表达水平。两组间比较采用t检验,多组间比较采用单因素方差分析,组间两两比较采用LSD-t检验。 结果与对照比较,缺氧处理的PC12细胞LDH漏出率[(9.46±0.97)﹪比(45.69±4.31)﹪]、细胞凋亡率[(5.36±0.54)﹪比(28.36±2.41)﹪]、MEF2A mRNA(1.00±0.08比2.74±0.26)和MEF2A蛋白表达水平(0.39±0.03比0.87±0.06)均升高;SOD活性[(12.24 ±1.13)比(5.13±0.52 )U/mL)]和miR-495-3p表达水平(1.00±0.08比0.35±0.03)均降低,差异有统计学意义(P均< 0.05)。与缺氧处理比较,缺氧+0.1、1、10 μg/mL TM干预的PC12细胞LDH漏出率[(45.69±4.31)﹪比(32.14±3.84)﹪、(23.54±3.17)﹪、(16.87±1.46)﹪]、细胞凋亡率[(28.36±2.41)﹪比(22.46±2.31)﹪、(17.14±1.65)﹪、(10.23±1.12)﹪]、MEF2A mRNA(2.74±0.26比2.26±0.23、1.87±0.19、1.34±0.18)和MEF2A蛋白表达水平(0.87±0.06比0.75±0.05、0.63±0.04、0.46±0.03)均降低;SOD活性[(5.13±0.52)比(6.87±0.69 )、(8.01±0.81)、(10.12±1.02)U/mL]、miR-495-3p表达水平(0.35±0.03比0.49±0.04、0.61±0.06、0.83±0.07)均升高,差异有统计学意义(P均< 0.05)。与缺氧+ miR-NC比较,缺氧+ miR-495-3p的PC12细胞LDH漏出率[(46.87±4.28)﹪比(19.65±1.87)﹪]和细胞凋亡率[(28.38±2.44)﹪比(12.36±1.25)﹪]均降低,SOD活性[(5.15±0.51)比(9.67±0.97)U/mL]升高,差异有统计学意义(P均< 0.05)。与缺氧+TM+anti-miR-NC比较,缺氧+TM+anti-miR-495-3p的PC12细胞LDH漏出率[(17.64±1.79)﹪比(32.69±3.57)﹪]和细胞凋亡率[(10.98±1.75)﹪比(22.64±2.13)﹪]均升高,SOD活性[(12.63±1.27)比(7.32±0.71)U/mL]降低,差异有统计学意义(P均< 0.05)。 结论TM通过上调miR-495-3p/MEF2A通路对缺氧诱导的PC12细胞损伤具有保护作用。  相似文献   
977.
Abscisic acid (ABA) is a key regulator of plant responses to abiotic stresses, such as drought. Abscisic acid receptors and coreceptors perceive ABA to activate Snf1-related protein kinase2s (SnRK2s) that phosphorylate downstream effectors, thereby activating ABA signaling and the stress response. As stress responses come with fitness penalties for plants, it is crucial to tightly control SnRK2 kinase activity to restrict ABA signaling. However, how SnRK2 kinases are inactivated remains elusive. Here, we show that NUCLEAR PORE ANCHOR (NUA), a nuclear pore complex (NPC) component, negatively regulates ABA-mediated inhibition of seed germination and post-germination growth, and drought tolerance in Arabidopsis thaliana. The role of NUA in response to ABA depends on SnRK2.2 and SnRK2.3 for seed germination and on SnRK2.6 for drought. NUA does not directly inhibit the phosphorylation of these SnRK2s or affects their abundance. However, the NUA-interacting protein EARLY IN SHORT DAYS 4 (ESD4), a SUMO protease, negatively regulates ABA signaling by directly interacting with and inhibiting SnRK2 phosphorylation and protein levels. More importantly, we demonstrated that SnRK2.6 can be SUMOylated in vitro, and ESD4 inhibits its SUMOylation. Taken together, we identified NUA and ESD4 as SnRK2 kinase inhibitors that block SnRK2 activity, and reveal a mechanism whereby NUA and ESD4 negatively regulate plant responses to ABA and drought stress possibly through SUMOylation-dependent regulation of SnRK2s.  相似文献   
978.
979.
980.
A luminous intensity variation fluorescent probe (Probe 1) for the detection of ferric ion was developed. The quantitative range of Fe3+ content detected was 0–600 μM with the limit of detection at 0.76 μM. Furthermore, after 20 min of Fe3+ addition, the intensity of the luminescence of Probe 1 solution gradually decreased with increase in Fe3+ concentration. In addition, the B and G values of these images showed a linear relationship with Fe3+ concentration (0–500 μM). Probe 1 was successfully used for the rapid determination of Fe3+ concentration in real samples. This study demonstrates that Probe 1 is an excellent tool for the rapid determination of Fe3+ content in real samples using a smart phone without professional equipment.  相似文献   
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