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941.
Neutrophils and macrophages are phagocytic cells that cooperate during inflammation and tissue repair. Neutrophils undergo
apoptosis and are engulfed by macrophages. Engulfment modulates macrophage activation and microbicidal activity. Infection
by Leishmania takes place in the context of tissue repair. This article discusses cellular and molecular mechanisms involved in the intimate
cooperation of neutrophils and macrophages in Leishmania infection. 相似文献
942.
Pattern recognition receptors are somatically encoded and participate in the innate immune responses of a host to microbes.
It is increasingly acknowledged that these receptors play a central role both in beneficial and pathogenic interactions with
microbes. In particular, these receptors participate actively in shaping the gut environment to establish a fruitful life-long
relationship between a host and its microbiota. Commensal bacteria engage Toll-like receptors (TLRs) and nucleotide oligomerization
domain (NOD)-like receptors (NLRs) to induce specific responses by intestinal epithelial cells such as production of antimicrobial
products or of a functional mucus layer. Furthermore, a complex crosstalk between intestinal epithelial cells and the immune
system is initiated leading to a mature gut-associated lymphoid tissue to secrete IgA. Impairment in NLR and TLR functionality
in epithelial cells is strongly associated with chronic inflammatory diseases such as Crohn’s disease, cancer, and with control
of the commensal microbiota creating a more favorable environment for the emergence of new infections. 相似文献
943.
Lesport E Baudhuin J Sousa S LeMaoult J Zamborlini A Rouas-Freiss N Carosella ED Favier B 《Cellular and molecular life sciences : CMLS》2011,68(20):3385-3399
Vγ9Vδ2 T cells play a crucial role in the antitumoral immune response through cytokine production and cytotoxicity. Although
the expression of the immunomodulatory molecule HLA-G has been found in diverse tumors, its impact on Vγ9Vδ2 T-cell functions
remains unknown. Here we showed that soluble HLA-G inhibits Vγ9Vδ2 T-cell proliferation without inducing apoptosis. Moreover,
soluble HLA-G inhibited the Vγ9Vδ2 T-cell production of IFN-γ induced by phosphoantigen stimulation. The reduction in Vγ9Vδ2
T-cell IFN-γ production was also induced by membrane-bound or soluble HLA-G expressed by tumor cell lines. Finally, primary
tumor cells inhibited Vγ9Vδ2 T-cell proliferation and IFN-γ production through HLA-G. In this context, HLA-G impaired Vγ9Vδ2
T-cell cytotoxicity by interacting with ILT2 inhibitory receptor. These data demonstrate that HLA-G inhibits the anti-tumoral
functions of Vγ9Vδ2 T cells and imply that treatments targeting HLA-G could optimize Vγ9Vδ2 T-cell-mediated immunotherapy
of cancer. 相似文献
944.
945.
946.
DNA replication is essential for accurate transmission of genomic information from parental to daughter cells. DNA replication
is licensed once per cell division cycle. This process is highly regulated by both positive and negative regulators. Over-replication,
under-replication, as well as DNA damage in a cell all induce the activation of checkpoint control pathways such as ATM/ATR,
CHK kinases, and the tumor suppressor protein p53, which provide “damage controls” via either DNA repairs or apoptosis. This
review focuses on accumulating evidence, with the emphasis on recently discovered Killin, that S-phase checkpoint control
is crucial for a mammalian cell to make a life and death decision in order to safeguard genome integrity. 相似文献
947.
Malgrange B Borgs L Grobarczyk B Purnelle A Ernst P Moonen G Nguyen L 《Cellular and molecular life sciences : CMLS》2011,68(4):635-649
Human pluripotent stem cells, including embryonic (hES) and induced pluripotent stem cells (hiPS), retain the ability to self-renew
indefinitely, while maintaining the capacity to differentiate into all cell types of the nervous system. While human pluripotent
cell-based therapies are unlikely to arise soon, these cells can currently be used as an inexhaustible source of committed
neurons to perform high-throughput screening and safety testing of new candidate drugs. Here, we describe critically the available
methods and molecular factors that are used to direct the differentiation of hES or hiPS into specific neurons. In addition,
we discuss how the availability of patient-specific hiPS offers a unique opportunity to model inheritable neurodegenerative
diseases and untangle their pathological mechanisms, or to validate drugs that would prevent the onset or the progression
of these neurological disorders. 相似文献
948.
From axon–glial signalling to myelination: the integrating role of oligodendroglial Fyn kinase 总被引:1,自引:1,他引:0
Central nervous system myelination requires recognition and signalling processes between neuronal axons and oligodendrocytes.
Complex cellular rearrangements occur in myelination-competent oligodendrocytes requiring spatio-temporal control mechanisms.
Although the molecular repertoire is becoming increasingly transparent, the signalling mechanisms governing myelination initiation
are only poorly understood. The non-receptor tyrosine kinase Fyn has been implicated in axon–glial signal transduction and
in several cellular processes required for oligodendrocyte maturation and myelination. Here, we review oligodendroglial Fyn
signalling and discuss the role of Fyn in axon–glia interaction mediating myelination. 相似文献
949.
Johansson ME Ambort D Pelaseyed T Schütte A Gustafsson JK Ermund A Subramani DB Holmén-Larsson JM Thomsson KA Bergström JH van der Post S Rodriguez-Piñeiro AM Sjövall H Bäckström M Hansson GC 《Cellular and molecular life sciences : CMLS》2011,68(22):3635-3641
In discussions on intestinal protection, the protective capacity of mucus has not been very much considered. The progress in the last years in understanding the molecular nature of mucins, the main building blocks of mucus, has, however, changed this. The intestinal enterocytes have their apical surfaces covered by transmembrane mucins and the whole intestinal surface is further covered by mucus, built around the gel-forming mucin MUC2. The mucus of the small intestine has only one layer, whereas the large intestine has a two-layered mucus where the inner, attached layer has a protective function for the intestine, as it is impermeable to the luminal bacteria. 相似文献
950.