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991.
992.
Xuejing Jia Yeer Liang Chao Zhang Kai Wang Yanbei Tu Meiwan Chen Peng Li Jian-Bo Wan Chengwei He 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(8):1751-1759
Background
Polysaccharides, one of the active ingredients in herbal medicine, are proved to enhance innate immunity against infections. The aim of this study is to explore the immunoregulatory ability of polysaccharides from Rhynchosia minima root in vitro and in vivo.Methods
Polysaccharide fractions of R. minima root were obtained by chromatographic column. The content of NO was measured by spectrophotometry. The levels of cytokines (tumor necrosis factor-α, TNF-α; interleukin-6, IL-6; and monocyte chemoattractant protein-1, MCP-1) were determined by enzyme-linked immuno-sorbent assay (ELISA) kits. The translocation of p65 into the nucleus was imaged by confocal microscopy. The mRNA expression of TNF-α, IL-6, and MCP-1 was determined by quantitative real-time PCR. T-lymphocyte subgroups of spleen from immunosuppressive mouse were evaluated by flow cytometry.Results
PRM3 remarkably enhanced the phagocytic ability of macrophages and promoted the release of NO and the secretion of cytokines (TNF-α, IL-6, and MCP-1) from macrophages. Simultaneously, PRM3 potently activated NF-κB signaling pathway via Toll-like receptor 4 (TLR4). In addition, PRM3 obviously increased the levels of serum cytokines, markedly up-regulated the percentages of CD3+ and CD4+ T lymphocytes and the CD4+/CD8+ ratio of splenocytes, and effectively attenuated cyclophosphamide induced immunosuppression in mice.Conclusions
PRM3 profoundly enhanced the immune function in vitro and in vivo through TLR4-NF-κB pathway and is a promising candidate of immunopotentiator which could be applied in functional foods or drugs.General significance
This study reported a polysaccharide PRM3 from R. minima root exhibited potent immunoenhancing activity and significantly alleviated cyclophosphamide-induced immunosuppression through TLR4-NF-κB pathway. 相似文献993.
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Longhai Liu Xiaoran Qian Mengling Chao Yijiao Zhao Junyi Huang Taichu Wang Fan Sun Erjun Ling Hongsheng Song 《Archives of insect biochemistry and physiology》2018,99(2)
Aluminum (Al) is an important environmental metal factor that can be potentially associated with pathological changes leading to neurotoxicity. The silkworm, Bombyx mori, is an important economic insect and has also been used as a model organism in various research areas. However, the toxicity of Al on silkworm physiology has not been reported. Here, we comprehensively investigate the toxic effects of Al on the silkworm, focusing on its effects on viability and development, superoxide dismutase (SOD) activity, and the expression of presenilin and cAMP response element‐binding protein (CREB) in BmE cells and silkworm larvae. BmE cell viability decreased after treatment with aluminum chloride (AlCl3) in both dose‐ and time‐dependent manners. When AlCl3 solution was injected into newly hatched fifth instar larvae, both larval weight gain and survival rate were significantly decreased in a manner correlating with AlCl3 dose and developmental stage. Furthermore, when BmE cells and silkworm larvae were exposed to AlCl3, SOD activity decreased significantly relative to the control group, whereas presenilin expression increased more than twofold. Additionally, CREB and phosphorylated CREB (p‐CREB) expression in the heads of fifth instar larvae decreased by 28.0% and 50.0%, respectively. These results indicate that Al inhibits the growth and development of silkworms in vitro and in vivo, altering SOD activity and the expressions of presenilin, CREB, and p‐CREB. Our data suggest that B. mori can serve as a model animal for studying Al‐induced neurotoxicity or neurodegeneration. 相似文献
996.
Chao Han Fangchao Liu Xueli Yang Jichun Chen Jianxin Li Jie Cao Ying Li Chong Shen Ling Yu Zhendong Liu Xianping Wu Liancheng Zhao Dongshen Hu Xiangfeng Lu Xigui Wu Dongfeng Gu 《中国科学:生命科学英文版》2018,61(5):504-514
Existing evidence on the relationship between cardiovascular health(CVH) metrics and cardiovascular disease(CVD) was primarily derived from western populations. We aimed to evaluate the benefits of ideal CVH metrics on preventing incident atherosclerotic CVD(ASCVD) in Chinese population. This study was conducted among 93,987 adults from the China-PAR project(Prediction for ASCVD Risk in China) who were followed up until 2015. Cox proportional hazard regression models were used to estimate the hazard ratios(HRs) and their corresponding 95% confidence intervals(CIs) of CVH metrics for the risk of ASCVD, including coronary heart disease(CHD), stroke and ASCVD death. We further estimated the population-attributable risk percentage(PAR%) of these metrics in relation to each outcome. We observed gradient inverse associations between the number of ideal CVH metrics and ASCVD incidence. Compared with participants having ≤2 ideal CVH metrics, the multivariable-adjusted HRs(95% CIs) of ASCVD for those with 3, 4, 5, 6 and 7 ideal CVH metrics were 0.83(0.74–0.93), 0.66(0.59–0.74), 0.55(0.48–0.61), 0.44(0.38–0.50) and 0.24(0.18–0.31), respectively(P for trend 0.0001). Approximately 62.1% of total ASCVD, 38.7% of CHD, 66.4% of stroke, and 60.5% of ASCVD death were attributable to not achieving all the seven ideal CVH metrics. After adjusting effects of ideal health factors, having four ideal health behaviors could independently bring adults health benefits in preventing 17.4% of ASCVD, 18.0% of CHD, 16.7% of stroke, and 10.1% of ASCVD death. Among all the seven CVH metrics, to keep with ideal blood pressure(BP) implied the largest public health gains against various ASCVD events(PAR% between 33.0% and 47.2%), while ideal diet was the metric most difficult to be achieved in the long term. Our study indicates that the more ideal CVH metrics adults have, the less ASCVD burden there is in China. Special efforts of health education and behavior modification should be made on keeping ideal BP and dietary habits in general Chinese population to prevent the epidemic of ASCVD. 相似文献
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Like protein and DNA, different types of RNA molecules undergo various modifications. Accumulating evidence suggests that these RNA modifications serve as sophisticated codes to mediate RNA behaviors and many important biological functions. N6-methyladenosine (m6A) is the most abundant internal RNA modification found in a variety of eukaryotic RNAs, including but not limited to mRNAs, tRNAs, rRNAs, and long non-coding RNAs (lncRNAs). In mammalian cells, m6A can be incorporated by a methyltransferase complex and removed by demethylases, which ensures that the m6A modification is reversible and dynamic. Moreover, m6A is recognized by the YT521-B homology (YTH) domain-containing proteins, which subsequently direct different complexes to regulate RNA signaling pathways, such as RNA metabolism, RNA splicing, RNA folding, and protein translation. Herein, we summarize the recent progresses made in understanding the molecular mechanisms underlying the m6A recognition by YTH domain-containing proteins, which would shed new light on m6A-specific recognition and provide clues to the future identification of reader proteins of many other RNA modifications. 相似文献
1000.
Hierarchical Zn–Co–S Nanowires as Advanced Electrodes for All Solid State Asymmetric Supercapacitors
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A facile two‐step strategy is developed to design the large‐scale synthesis of hierarchical, unique porous architecture of ternary metal hydroxide nanowires grown on porous 3D Ni foam and subsequent effective sulfurization. The hierarchical Zn–Co–S nanowires (NWs) arrays are directly employed as an electrode for supercapacitors application. The as‐synthesized Zn–Co–S NWs deliver an ultrahigh areal capacity of 0.9 mA h cm?2 (specific capacity of 366.7 mA h g?1) at a current density of 3 mA cm?2, with an exceptional rate capability (≈227.6 mA h g?1 at a very high current density of 40 mA cm?2) and outstanding cycling stability (≈93.2% of capacity retention after 10 000 cycles). Most significantly, the assembled Zn–Co–S NWs//Fe2O3@reduced graphene oxide asymmetric supercapacitors with a wide operating potential window of ≈1.6 V yield an ultrahigh volumetric capacity of ≈1.98 mA h cm?3 at a current density of 3 mA cm?2, excellent energy density of ≈81.6 W h kg?1 at a power density of ≈559.2 W kg?1, and exceptional cycling performance (≈92.1% of capacity retention after 10 000 cycles). This general strategy provides an alternative to design the other ternary metal sulfides, making it facile, free‐standing, binder‐free, and cost‐effective ternary metal sulfide‐based electrodes for large‐scale applications in modern electronics. 相似文献