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21.
The role of the CcpA transcriptional regulator in carbon metabolism in Bacillus subtilis 总被引:2,自引:0,他引:2
Tina M. Henkin 《FEMS microbiology letters》1996,135(1):9-15
22.
Tina Hennerici Robert Pollmann Thomas Schmidt Maria Seipelt Bj?rn Tackenberg Christian M?bs Kamran Ghoreschi Michael Hertl Rüdiger Eming 《PloS one》2016,11(2)
Pemphigus is an autoimmune disease in which IgG auto-antibodies (auto-ab) against the desmosomal cadherins desmoglein (Dsg) 3 and Dsg1 cause loss of epidermal keratinocyte adhesion. Aim of this study was to investigate cytokines derived from antigen-presenting cells (APC) and their relation to CD4+ T cell subpopulations and to the auto-ab response in pemphigus. In this regard, patients with pemphigus were compared to patients with myasthenia gravis (MG), an unrelated auto-ab–mediated autoimmune disease, and healthy controls. In pemphigus and MG, the plasma concentrations of the APC-derived immunomodulatory cytokine IL-27 were highly increased. Strikingly, IL-27 strongly correlated with Dsg-specific IgG auto-ab titers. T helper (Th) 17 cells were augmented in both pemphigus and MG patients while T follicular helper (Tfh) cells, which are essential in providing B cell help, were increased only in pemphigus along with increasing plasma concentrations of IL-21, a cytokine produced by Th17 and Tfh cells. Moreover, we could detect Dsg3-specific autoreactive T cells producing IL-21 upon ex vivo stimulation with Dsg3. These findings suggest that IL-27 and IL-21-producing T cells, are involved in the pathogenesis of pemphigus. The further characterization of IL-21-producing T cells and of the role of IL-27 will lead to a more defined understanding of the auto-ab response in pemphigus. 相似文献
23.
U.S. women of childbearing age who are at possible increased risk of a neural tube defect‐affected pregnancy due to suboptimal red blood cell folate concentrations,National Health and Nutrition Examination Survey 2007 to 2012 下载免费PDF全文
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PARP-1 (poly(ADP-ribose) polymerases) modifies proteins with poly(ADP-ribose), which is an important signal for genomic stability. ADP-ribose polymers also mediate cell death and are degraded by poly(ADP-ribose) glycohydrolase (PARG). Here we show that the catalytic domain of PARG interacts with the automodification domain of PARP-1. Furthermore, PARG can directly down-regulate PARP-1 activity. PARG also interacts with XRCC1, a DNA repair factor that is recruited by DNA damage-activated PARP-1. We investigated the role of XRCC1 in cell death after treatment with supralethal doses of the alkylating agent MNNG. Only in XRCC1-proficient cells MNNG induced a considerable accumulation of poly(ADP-ribose). Similarly, extracts of XRCC1-deficient cells produced large ADP-ribose polymers if supplemented with XRCC1. Consequently, MNNG triggered in XRCC1-proficient cells the translocation of the apoptosis inducing factor from mitochondria to the nucleus followed by caspase-independent cell death. In XRCC1-deficient cells, the same MNNG treatment caused non-apoptotic cell death without accumulation of poly(ADP-ribose). Thus, XRCC1 seems to be involved in regulating a poly(ADP-ribose)-mediated apoptotic cell death. 相似文献
27.
Le Zhang Sun-Ok Fernandez-Kim Tina L. Beckett Dana M. Niedowicz Katharina Kohler Kalavathi Dasuri Annadora J. Bruce-Keller M. Paul Murphy Jeffrey N. Keller 《生物化学与生物物理学报:疾病的分子基础》2019,1865(9):2157-2167
Alzheimer's disease (AD) is the most common age-related neurodegenerative disease, while obesity is a major global public health problem associated with the metabolic disorder type 2 diabetes mellitus (T2DM). Chronic obesity and T2DM have been identified as invariant risk factors for dementia and late-onset AD, while their impacts on the occurrence and development of AD remain unclear. As shown in our previous study, the diabetic mutation (db, Leprdb/db) induces mixed or vascular dementia in mature to middle-aged APPΔNL/ΔNL x PS1P264L/P264L knock-in mice (db/AD). In the present study, the impacts of the db mutation on young AD mice at 10 weeks of age were evaluated. The db mutation not only conferred young AD mice with severe obesity, impaired glucose regulation and activated mammalian target of rapamycin (mTOR) signaling pathway in the mouse cortex, but lead to a surprising improvement in memory. At this young age, mice also had decreased cerebral Aβ content, which we have not observed at older ages. This was unlikely to be related to altered Aβ synthesis, as both β- and γ-secretase were unchanged. The db mutation also reduced the cortical IL-1β mRNA level and IBA1 protein level in young AD mice, with no significant effect on the activation of microglia and astrocytes. We conclude that the db mutation could transitorily improve the memory of young AD mice, a finding that may be partially explained by the relatively improved glucose homeostasis in the brains of db/AD mice compared to their counterpart AD mice, suggesting that glucose regulation could be a strategy for prevention and treatment of neurodegenerative diseases like AD. 相似文献
28.
Background
Previous studies have demonstrated that knockout or inhibition of Platelet/Endothelial Cell Adhesion Molecule (PECAM, CD31) in a number of murine strains results in impaired inflammatory responses, but that no such phenotype is seen in the C57BL/6 (B6) murine background.Methodology/Principal Findings
We have undertaken a quantitative trait locus (QTL) mapping effort between FVB/n (FVB) and B6 mice deficient for PECAM to identify the gene or genes responsible for this unique feature of B6 mice. We have identified a locus on murine chromosome 2 at approximately 35.8 Mb that is strongly associated (LOD score = 9.0) with inflammatory responses in the absence of PECAM.Conclusions/Significance
These data potentiate further study of the diapedesis machinery, as well as potential identification of new components of this machinery. As such, this study is an important step to better understanding the processes of inflammation. 相似文献29.
Lee CC Smith M Kibblewhite-Accinelli RE Williams TG Wagschal K Robertson GH Wong DW 《Current microbiology》2006,52(2):112-116
Xylan is the major component of hemicellulose, and xylan should be fully utilized to improve the efficiencies of a biobased
economy. There are a variety of industrial reaction conditions in which an active xylanase enzyme would be desired. As a result,
xylanase enzymes with different activity profiles are of great interest. We isolated a xylanase gene (xyn10) from a Flavobacterium sp. whose sequence suggests that it is a glycosyl hydrolase family 10 member. The enzyme has a temperature optimum of 30°C,
is active at cold temperatures, and is thermolabile. The enzyme has an apparent Km of 1.8 mg/ml and kcat of 100 sec−1 for beechwood xylan, attacks highly branched native xylan substrates, and does not have activity against glucans. 相似文献
30.
c-Myc affects mRNA translation, cell proliferation and progenitor cell function in the mammary gland