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261.
Ga Hun Boo Ying‐Xiong Qiu Jung Yeon Kim Put O. Ang Samuel Bosch Olivier De Clerck Peimin He Atsushi Higa Bangqin Huang Kazuhiro Kogame Shao‐Lun Liu Tu van Nguyen Shoichiro Suda Ryuta Terada Kathy Ann Miller Sung Min Boo 《Journal of phycology》2019,55(6):1319-1334
The evolutionary and population demographic history of marine red algae in East Asia is poorly understood. Here, we reconstructed the phylogeographies of two upper intertidal species endemic to East Asia, Gelidiophycus divaricatus and G. freshwateri. Phylogenetic and phylogeographic inferences of 393 mitochondrial cox1, 128 plastid rbcL, and 342 nuclear ITS2 sequences were complemented with ecological niche models. Gelidiophycus divaricatus, a southern species adapted to warm water, is characterized by a high genetic diversity and a strong geographical population structure, characteristic of stable population sizes and sudden reduction to recent expansion. In contrast, G. freshwateri, a northern species adapted to cold temperate conditions, is genetically relatively homogeneous with a shallow population structure resulting from steady population growth and recent equilibrium. The overlap zone of the two species roughly matches summer and winter isotherms, indicating that surface seawater temperature is a key feature influencing species range. Unidirectional genetic introgression was detected at two sites on Jeju Island where G. divaricatus was rare while G. freshwateri was common, suggesting the occurrence of asymmetric natural hybrids, a rarely reported event for rhodophytes. Our results illustrate that Quaternary climate oscillations have left strong imprints on the current day genetic structure and highlight the importance of seawater temperature and sea level change in driving speciation in upper intertidal seaweed species. 相似文献
262.
Shan Song Duojun Qiu Yonghong Shi Shuai Wang Xinbo Zhou Nan Chen Jinying Wei Ming Wu Haijiang Wu Huijun Duan 《Journal of cellular physiology》2019,234(9):16485-16502
Thioredoxin-interacting protein (TXNIP) is induced by high glucose (HG), whereupon it acts to inhibit thioredoxin, thereby promoting oxidative stress. We have found that TXNIP knockdown in human renal tubular cells helped prevent the epithelial-to-mesenchymal transition (EMT). Here, we studied the potential effect of TXNIP on podocyte phenotypic alterations in diabetic nephropathy (DN) in vivo and in vitro. In conditionally immortalized mouse podocytes under HG conditions, knocking down TXNIP disrupted EMT, reactive oxygen species (ROS) production, and mammalian target of rapamycin (mTOR) pathway activation. Further, Raptor short hairpin RNA (shRNA), Rictor shRNA, and mTOR specific inhibitor KU-0063794 were used to assess if the mTOR signal pathway is involved in HG-induced EMT in podocytes. We found that Raptor shRNA, Rictor shRNA, and KU-0063794 could all restrain HG-induced EMT and ROS production in podocytes. In addition, antioxidant Tempol or N-acetylcysteine presented a prohibitive effect on HG-induced EMT in podocytes. Streptozotocin was utilized to render equally diabetic in wild-type (WT) control and TXNIP −/− (TKO) mice. Diabetes did not increase levels of 24-hr urinary protein, serum creatinine, blood urea nitrogen, and triglyceride in TXNIP −/− mice. Podocyte phenotypic alterations and podocyte loss were detected in WT but not in TKO diabetic mice. Oxidative stress was also suppressed in diabetic TKO mice relative to WT controls. Also, TXNIP deficiency suppresses the activation of mTOR in glomeruli of streptozotocin-induced diabetic mice. Moreover, TXNIP expression, mTOR activation, Nox1, and Nox4 could be detected in renal biopsy tissues of patients with DN. This suggests that decreased TXNIP could ameliorate phenotypic alterations of podocytes via inhibition of mTOR in DN, highlighting TXNIP as a promising therapeutic target. 相似文献
263.
Junyu Lai Manqing Ge Sikui Shen Lu Yang Tao Jin Dehong Cao Hang Xu Xiaonan Zheng Shi Qiu Kunjie Wang Qiang Wei Hong Li Jianzhong Ai 《生物化学与生物物理学报:疾病的分子基础》2019,1865(9):2403-2410
Chronic cystitis is characterized by the hyperplasia and fibrosis of the bladder wall as well as attenuated compliance of the bladder. To further unravel its underlying molecular mechanism, the role of NFκB-JMJD3 signaling pathway in cystitis induced bladder fibrosis was investigated. Jmjd3 and Col1/3 expression was detected in a cystitis mouse model that was developed by intraperitoneal injection of cyclophosphamide (CYP). Human bladder smooth muscle cells (hBSMCs) were stimulated in vitro with lipopolysaccharide (LPS), and the cell proliferation and collagen accumulation were detected using EdU, CCK8, flow cytometry, qPCR, western blotting and immunofluorescence assays. Furthermore, the effects of NFκB and JMJD3 on cell proliferation and collagen accumulation were investigated using its selective antagonists, JSH23 and GSK-J4, respectively. CYP induced cystitis significantly increased Jmjd3, Col1 and Col3 expression in the bladder muscle cells. Furthermore, LPS stimulation markedly activated NFκB signaling and elevated JMJD3 expression in hBSMCs, and the activation of NFκB-JMJD3 signaling significantly promoted cell proliferation and collagen accumulation by upregulating CCND1 and COL1/3 expression, respectively. Our study reveals the critical role of NFκB-JMJD3 signaling in cystitis induced bladder reconstruction by regulating hBSMC proliferation and extracellular matrix (ECM) deposition, and these findings provide an avenue for effective treatment of patients with cystitis. 相似文献
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266.
Shu Shen Junjie Kong Yiwen Qiu Xianwei Yang Wentao Wang Lvnan Yan 《Journal of cellular biochemistry》2019,120(6):10069-10081
Hepatocellular carcinoma (HCC) is the most common malignant liver disease in the world. However, the mechanistic relationships among various genes and signaling pathways are still largely unclear. In this study, we aimed to elucidate potential core candidate genes and pathways in HCC. The expression profiles GSE14520, GSE25097, GSE29721, and GSE62232, which cover 606 tumor and 550 nontumour samples, were downloaded from the Gene Expression Omnibus (GEO) database. Furthermore, HCC RNA-seq datasets were also downloaded from the Cancer Genome Atlas (TCGA) database. The differentially expressed genes (DEGs) were filtered using R software, and we performed gene ontology (GO) and Kyoto Encyclopedia of Gene and Genome (KEGG) pathway analysis using the online databases DAVID 6.8 and KOBAS 3.0. Furthermore, the protein-protein interaction (PPI) network complex of these DEGs was constructed by Cytoscape software, the molecular complex detection (MCODE) plug-in and the online database STRING. First, a total of 173 DEGs (41 upregulated and 132 downregulated) were identified that were aberrantly expressed in both the GEO and TCGA datasets. Second, GO analysis revealed that most of the DEGs were significantly enriched in extracellular exosomes, cytosol, extracellular region, and extracellular space. Signaling pathway analysis indicated that the DEGs had common pathways in metabolism-related pathways, cell cycle, and biological oxidations. Third, 146 nodes were identified from the DEG PPI network complex, and two important modules with a high degree were detected using the MCODE plug-in. In addition, 10 core genes were identified, TOP2A, NDC80, FOXM1, HMMR, KNTC1, PTTG1, FEN1, RFC4, SMC4, and PRC1. Finally, Kaplan-Meier analysis of overall survival and correlation analysis were applied to these genes. The abovementioned findings indicate that the identified core genes and pathways in this bioinformatics analysis could significantly enrich our understanding of the development and recurrence of HCC; furthermore, these candidate genes and pathways could be therapeutic targets for HCC treatment. 相似文献
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268.
Zhibing Qiu Xin Chen Li Yin Wen Chen Yueyue Xu Ben Jiang 《Journal of cellular biochemistry》2019,120(2):2323-2335
Previous studies have shown that stomatin-like protein-2 (SLP-2) could regulate mitochondrial biogenesis and function. The study was designed to explore the contribution of SLP-2 to the myocardial ischemia and reperfusion (I/R) injury. Anesthetized rats were treated with SLP-2 and subjected to ischemia for 30 minutes before 3 hours of reperfusion. An oxygen-glucose deprivation/reoxygenation model of I/R was established in H9C2 cells. In vivo, SLP-2 significantly improved cardiac function recovery of myocardial I/R injury rats by increasing fractional shortening and ejection fraction. SLP-2 pretreatment alleviated infarct area and myocardial apoptosis, which was paralleled by decreasing the level of cleaved caspase-3 and the ratio of Bax/Bcl-2, increasing the content of superoxide dismutase and reducing oxidative stress damage in serum. In addition, SLP-2 increased the level of ATP and stabilized mitochondrial potential (Ψm). The present in vitro study revealed that overexpression with SLP-2 reduced H9C2 cells apoptosis, accompanied by an increased level of ATP, the ratio of mitochondrial DNA/nuclear DNA, activities of complex II and V, and decreased the production of mitochondrial reactive oxygen species. Simultaneously, SLP-2 activated the adenosine 5′-monophosphate-activated protein kinase (AMPK) signaling pathway in myocardial I/R injury rats and H9C2 cells. This study revealed that SLP-2 mediates the cardioprotective effect against I/R injury by regulating AMPK signaling pathway. 相似文献
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270.
Yong-Qiang Deng Na-Na Zhang Yi-Fei Zhang Xia Zhong Sue Xu Hong-Ying Qiu Tie-Cheng Wang Hui Zhao Chao Zhou Shu-Long Zu Qi Chen Tian-Shu Cao Qing Ye Hang Chi Xiang-Hui Duan Dan-Dan Lin Xiao-Jing Zhang Liang-Zhi Xie Yu-Wei Gao Bo Ying Cheng-Feng Qin 《Cell research》2022,32(4):375
Monoclonal antibodies represent important weapons in our arsenal to against the COVID-19 pandemic. However, this potential is severely limited by the time-consuming process of developing effective antibodies and the relative high cost of manufacturing. Herein, we present a rapid and cost-effective lipid nanoparticle (LNP) encapsulated-mRNA platform for in vivo delivery of SARS-CoV-2 neutralization antibodies. Two mRNAs encoding the light and heavy chains of a potent SARS-CoV-2 neutralizing antibody HB27, which is currently being evaluated in clinical trials, were encapsulated into clinical grade LNP formulations (named as mRNA-HB27-LNP). In vivo characterization demonstrated that intravenous administration of mRNA-HB27-LNP in mice resulted in a longer circulating half-life compared with the original HB27 antibody in protein format. More importantly, a single prophylactic administration of mRNA-HB27-LNP provided protection against SARS-CoV-2 challenge in mice at 1, 7 and even 63 days post administration. In a close contact transmission model, prophylactic administration of mRNA-HB27-LNP prevented SARS-CoV-2 infection between hamsters in a dose-dependent manner. Overall, our results demonstrate a superior long-term protection against SARS-CoV-2 conferred by a single administration of this unique mRNA antibody, highlighting the potential of this universal platform for antibody-based disease prevention and therapy against COVID-19 as well as a variety of other infectious diseases.Subject terms: Biological techniques, Immunology 相似文献