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951.
Adenoviral proteins mimic nutrient/growth signals to activate the mTOR pathway for viral replication 总被引:4,自引:0,他引:4
O'Shea C Klupsch K Choi S Bagus B Soria C Shen J McCormick F Stokoe D 《The EMBO journal》2005,24(6):1211-1221
Like tumor cells, DNA viruses have had to evolve mechanisms that uncouple cellular replication from the many intra- and extracellular factors that normally control it. Here we show that adenovirus encodes two proteins that activate the mammalian target of rapamycin (mTOR) for viral replication, even under nutrient/growth factor-limiting conditions. E4-ORF1 mimics growth factor signaling by activating PI3-kinase, resulting in increased Rheb.GTP loading and mTOR activation. E4-ORF4 is redundant with glucose in stimulating mTOR, does not affect Rheb.GTP levels and is the major mechanism whereby adenovirus activates mTOR in quiescent primary cells. We demonstrate that mTOR is activated through a mechanism that is dependent on the E4-ORF4 protein phosphatase 2A-binding domain. We also show that mTOR activation is required for efficient S-phase entry, independently of E2F activation, in adenovirus-infected quiescent primary cells. These data reveal that adenovirus has evolved proteins that activate the mTOR pathway, irrespective of the cellular microenvironment, and which play a requisite role in viral replication. 相似文献
952.
Jiwoon Kim Keemin Park Minsung Kim Hyungjun Lee Junghyun Choi Ho Bum Park Hansu Kim Jaeyoung Jang Young-Hoon Kim Taeseup Song Ungyu Paik 《Liver Transplantation》2024,14(10):2303455
Roll-to-roll dry processing enables the manufacture of high energy density and low cost Li-ion batteries (LIBs). However, as the thickness of the electrode fabricated by dry processing becomes greater (≥10 mAh cm−2), Li-ion migration resistance (Rion) and charge-transfer resistance (Rct) in the electrode dramatically increase due to long diffusion lengths for Li-ion and electron. Therefore, it is important to reduce diffusion lengths in the electrode to achieve high energy density LIBs. The dry electrode with a high areal capacity of 10 mAh cm−2 and low resistance can be achieved by following three characteristics. First, the fibrillization behavior of polytetrafluoroethylene (PTFE) binder is controlled by adjusting the processing temperature during the fibrillization process, which enables uniform distribution of PTFE binder and carbon black (CB). Second, pore size/distribution and conducting network are engineered by multi-dimensional conducting agents, enhancing Li-ions and electrons transport in the electrode. Finally, the structural integrity of LiNi0.80Co0.15Al0.05O2 (NCA) particles is improved without fractures, which enables uniform pore distribution in the electrode by controlling the calendering step. The prepared 10 mAh cm−2 dry electrode with homogeneous microstructure shows reduced Rion and Rct due to short diffusion lengths, which improves electrochemical performances in LIBs with a high volumetric energy density of ≈710 Wh L−1. 相似文献
953.
SUMMARY: TO-GO is a Gene Ontology (GO) navigation tool, which is implemented as a Java application. After the initial data downloading, the GO term tree can be interactively navigated without further network transfer. Local annotation can be incorporated. It supports querying by GO terms or associated gene product information, displaying the result as a table or a sub-tree. The result from the search for a set of external database accessions includes the number of gene products associated with each node, inclusive of sub-nodes. Search results can be further processed by set operations and these set operations can be quite useful for expression profile data analysis. A copy/paste function is also implemented in order to facilitate data exchange between applications. AVAILABILITY: TO-GO is freely available at http://www.ngic.re.kr/togo/index.html CONTACT: ungsik@kribb.re.kr 相似文献
954.
So Yung Yang Ji Hyun Baek Youngah Cho Eun-Young Cho Yujin Choi Yongkang Kim 《Chronobiology international》2018,35(3):405-415
ST8SIA2 and NCAM1 are functionally related genes forming polysialic acid (PSA) - neural cell adhesion molecule (NCAM) complex in suprachiasmatic nucleus (SCN), the regulating site of circadian biological rhythm. In this study, the relationship of ST8SIA2 and NCAM1 with circadian and seasonal rhythms of human behavior was explored. Subjects were 261 healthy Korean adults who were free of any history of clinically significant psychiatric symptoms. The phenotypes were circadian preference and seasonal change of mood and behavior (seasonality) measured by the Composite Scale of Morningness and the Seasonal Pattern Assessment Questionnaire, respectively. Thirty-four single nucleotide polymorphisms (SNPs) across the ST8SIA2 region and 15 SNPs of NCAM1 were analyzed. A nominally significant association with seasonality and circadian preference was observed in 21 variants of both genes. After corrections for multiple testing, associations of 8 SNPs of ST8SIA2 and 2 SNPs of NCAM1 with seasonality remained significant. Some of these SNPs were also associated with psychiatric disorders in previous studies. This study demonstrated a meaningful and/or suggestive evidence of association between behavioral phenotypes reflecting human biological rhythm and two interplaying genes involved in the plasticity of SCN’s neuronal network. 相似文献
955.
956.
957.
Jung Won Shin Sung Hee Choi Dong Eun Kim Hee Sook Kim Jae-Hwa Lee In Su Lee Eun Yeol Lee 《Bioprocess and biosystems engineering》2011,34(1):113-119
The marine alginate lyase from Streptomyces sp. ALG-5, which specifically degrades poly-G block of alginate, was functionally expressed as a His-tagged form with an
Escherichia coli expression system. The recombinant alginate lyase expressed with pColdI at 15 °C exhibited the highest alginate-degrading
activity. The recombinant alginate lyase was efficiently immobilized onto two types of magnetic nanoparticles, superparamagnetic
iron oxide nanoparticle, and hybrid magnetic silica nanoparticle, based on the affinity between His-tag and Ni2+ that displayed on the surfaces of nanoparticles. An alginate oligosaccharide mixture consisting of dimer and trimer was prepared
by the immobilized alginate lyase. The immobilized enzymes were re-used repeatedly more than 10 times after magnetic separation. 相似文献
958.
959.
The objectives of this study were to test the effects of light on melatonin rhythms in the pineal gland and gut of goldfish Carassius auratus and to investigate whether melatonin function differed in these two tissues, which are photosensitive and non-photosensitive respectively. Rhythms were evaluated by measuring arylalkylamine N-acetyltransferase (AANAT2) and melatonin receptor 1 (MT-R1) mRNA expression and melatonin concentration in the pineal gland, gut (in vivo), and cell cultures of the two tissues (in vitro). Compared to control, pineal gland melatonin secretion was higher at night, whereas the 24-h dark and ophthalmectomy groups maintained higher AANAT2 and MT-R1 mRNA expression during the day. Melatonin levels and AANAT2 and MT-R1 mRNA expression in the gut were also the highest at night, but the 24-h light, dark, and ophthalmectomy groups did not significantly differ from control. Furthermore, we measured AANAT2 and MT-R1 mRNA expression in high temperature water (30 °C) to investigate differences in the antioxidant capacity of pineal gland vs. gut melatonin. Melatonin and H2O2 levels, as well as AANAT2 and MT-R1 mRNA expression, were all higher in the two tissues under thermal stress, compared with their levels at 22 °C. Taken together, our results suggest that light has no effect on melatonin patterns in the gut, which appears to exhibit its own circadian rhythm, but both gut and pineal gland melatonin exhibit similar antioxidant function. 相似文献
960.
Yi SS Hwang IK Kim DW Shin JH Nam SM Choi JH Lee CH Won MH Seong JK Yoon YS 《Neurochemical research》2011,36(1):117-128
Because it appears that oxidative stress and inflammation are implicated with disease pathogenesis in the diabetic brain,
many researchers have used streptozotocin (STZ)-induced diabetic animals to study superoxide production and the effects of
superoxide scavengers like Cu,Zn-superoxide dismutase (SOD1). However, many studies have been conducted without considering
temporal changes after STZ injection. Interestingly, though SOD activities were not significantly different among the groups,
SOD1 and 4-hydroxy-2-nonenal (4-HNE) immunoreactivities were significantly enhanced at 3 weeks after an STZ injection (STZ3w)
versus only marginal levels in sham controls, whereas microglial activity was remarkably reduced in injected rats at this
time. However, SOD1 immunoreactivity and microglial activities were only at the sham level at STZ4w. The present study provides
important information concerning cell damage by ROS generated by STZ. Microglial response was found to be inactivated at STZ3w
and neuronal cells (NeuN) showed a non-significant tendency to be reduced in number at STZ4w except in the dentate gyrus.
We speculated that the above oxidative stress-related events should be accomplished at STZ3w in the brains of STZ-induced
diabetes animal models. Therefore, the aim of the present study was to investigate chronological changes in SOD1 immunoreactivity
associated with lipid peroxidation and inflammatory responses in the hippocampi of STZ-induced type I diabetic rats. 相似文献