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991.
Wan‐Yi Huang Ya‐Pei Wang Yasser S. Mahmmod Jun‐Jie Wang Tang‐Hui Liu Yu‐Xiang Zheng Xue Zhou Xiu‐Xiang Zhang Zi‐Guo Yuan 《Proteomics》2019,19(3)
Sprague Dawley rats and Kunming (KM) mice are artificially infected with type II Toxoplasma gondii strain Prugniaud (Pru) to generate toxoplasmosis, which is a fatal disease mediated by T. gondii invasion of the central nervous system (CNS) by unknown mechanisms. The aim is to explore the mechanism of differential susceptibility of mice and rats to T. gondii infection. Therefore, a strategy of isobaric tags for relative and absolute quantitation (iTRAQ) is established to identify differentially expressed proteins (DEPs) in the rats’ and the mice's brains compared to the healthy groups. In KM mice, which is susceptible to T. gondii infection, complement component 3 (C3) is upregulated and the tight junction (TJ) pathway shows a disorder. It is presumed that T. gondii‐stimulated C3 disrupts the TJ of the blood–brain barrier in the CNS. This effect allows more T. gondii passing to the brain through the intercellular space. 相似文献
992.
Rui Zhang Wan Yu Guanyu Liang Zhanjun Jia Zhengxin Chen Lin Zhao Yongsheng Yuan Xiaobin Zhou Daqian Li Shuying Shen Ning Liu Aihua Zhang Huibo Wang Gang Wang 《Cellular and molecular neurobiology》2017,37(1):37-42
Glioblastoma (GBM) is the most common malignant brain tumor with poor prognosis and limited treatment options. Tumor suppressor candidate 1 (TUSC1) was recently identified as a potential tumor suppressor in human cancers. However, the expression and potential function of TUSC1 in GBM remain unclear. Herein, we report that TUSC1 is significantly decreased in GBM tissues and cell lines. Patients with high levels of TUSC1 displayed a significant better survival compared with those with low levels of TUSC1. Functional experiments demonstrated that exogenous expression of TUSC1 inhibited GBM cell proliferation and induced G1 phase arrest by down-regulating CDK4. Moreover, overexpression of TUSC1 retarded tumor growth in vivo. Together, our findings revealed that TUSC1 might be a crucial tumor suppressor gene and a novel therapeutic target for GBM. 相似文献
993.
Xuan Li Xiao‐Tao He Yuan Yin Rui‐Xin Wu Bei‐Min Tian Fa‐Ming Chen 《Journal of cellular and molecular medicine》2017,21(12):3162-3177
Ex vivo‐expanded stem cells have long been a cornerstone of biotherapeutics and have attracted increasing attention for treating intractable diseases and improving tissue regeneration. However, using exogenous cellular materials to develop restorative treatments for large numbers of patients has become a major concern for both economic and safety reasons. Advances in cell biological research over the past two decades have expanded the potential for using endogenous stem cells during wound healing processes, and in particular, recent insight into stem cell movement and homing has prompted regenerative research and therapy based on recruiting endogenous cells. Inspired by the natural healing process, artificial administration of specific chemokines as signals systemically or at the injury site, typically using biomaterials as vehicles, is a state‐of‐the‐art strategy that potentiates stem cell homing and recreates an anti‐inflammatory and immunomodulatory microenvironment to enhance in situ tissue regeneration. However, pharmacologically coaxing endogenous stem cells to act as therapeutics in the field of biomedicine remains in the early stages; its efficacy is limited by the lack of innovative methodologies for chemokine presentation and release. This review describes how to direct the homing of endogenous stem cells via the administration of specific signals, with a particular emphasis on targeted signalling molecules that regulate this homing process, to enhance in situ tissue regeneration. We also provide an outlook on and critical considerations for future investigations to enhance stem cell recruitment and harness the reparative potential of these recruited cells as a clinically relevant cell therapy. 相似文献
994.
Xiaochen Xu Michaela Egger Hao Chen Karolina Bartosik Ronald Micura Aiming Ren 《Nucleic acids research》2021,49(12):7139
Riboswitches are conserved functional domains in mRNA that mostly exist in bacteria. They regulate gene expression in response to varying concentrations of metabolites or metal ions. Recently, the NMT1 RNA motif has been identified to selectively bind xanthine and uric acid, respectively, both are involved in the metabolic pathway of purine degradation. Here, we report a crystal structure of this RNA bound to xanthine. Overall, the riboswitch exhibits a rod-like, continuously stacked fold composed of three stems and two internal junctions. The binding-pocket is determined by the highly conserved junctional sequence J1 between stem P1 and P2a, and engages a long-distance Watson–Crick base pair to junction J2. Xanthine inserts between a G–U pair from the major groove side and is sandwiched between base triples. Strikingly, a Mg2+ ion is inner-sphere coordinated to O6 of xanthine and a non-bridging oxygen of a backbone phosphate. Two further hydrated Mg2+ ions participate in extensive interactions between xanthine and the pocket. Our structure model is verified by ligand binding analysis to selected riboswitch mutants using isothermal titration calorimetry, and by fluorescence spectroscopic analysis of RNA folding using 2-aminopurine-modified variants. Together, our study highlights the principles of metal ion-mediated ligand recognition by the xanthine riboswitch. 相似文献
995.
呼吸道合胞病毒B亚型分离株的G蛋白基因分析 总被引:2,自引:0,他引:2
对一株长春地区B亚型分离株(CC169)的G蛋白基因进行了
序列分析,结果表明:我国呼吸道合胞病毒(RSV)分离株CC169同RSV B亚型原型株CH18537的
核苷酸同源性为94%,核苷酸的有义突变率达65%。由核苷酸推导出氨基酸序列的同源性为894%,氨基酸的变异全部发生在胞外区,并主要集中在一个高度保守区的两端,胞内区和跨
膜区保守不变。氨基酸的变异导致了分离株既有糖基化位点的改变,又有蛋白长度的变异。
此外还初步探讨了我国RSV B 亚型分离株CC169的G蛋白基因同原型株之间的变异与疫苗研制
中的意义。 相似文献
996.
球形芽孢杆菌C3-41是我国分离的一株对蚊幼虫有毒杀作用的高毒力菌株,对库蚊、按蚊幼虫的毒性高于2362菌株,Southern杂交证明C3-41总DNA中3.5KbHindIII片段上带有41.9和51.4kD二元毒素基因。 相似文献
997.
土耳其斯坦叶螨的生物学特性及其综合防治 总被引:7,自引:0,他引:7
叙述新疆棉花上土耳其斯坦叶螨的危害、发生规律,传播、猖獗因素及综合防治技术。 相似文献
998.
Effects of branched‐chain amino acid supplementation on fecundity,lifespan and flight ability of Helicoverpa armigera 下载免费PDF全文
The effects on cotton bollworm, Helicoverpa armigera, of supplementing the benchmark larval feeding formula with branched‐chain amino acids (BCAAs) were analyzed. The results show that supplementary BCAAs can increase adult longevity, and are conducive to improving development and reproductive capacity. In particular, by supplementing the ration with the three proteinogenic BCAAs at concentrations ten times that of the benchmark formula, all the selected physiological indices of cotton bollworm health were improved. The larval duration, pupae weight, pupation rate, fecundity and adult longevity for specimens fed the supplemented formula were 15.8 days, 0.348 g, 100%, 1340.7 eggs and 27.3 days, respectively. The same indicators for larvae fed the benchmark formula were 16.6 days, 0.306 g, 97.9%, 1167.0 eggs and 12.0 days, respectively. This study provides a reference for future research on amino acid supplementation and increasing lifespans 相似文献
999.
Inhibition of Gli/hedgehog signaling in prostate cancer cells by “cancer bush” Sutherlandia frutescens extract 下载免费PDF全文