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71.
Rai A Nöthe H Tzvetkov N Korenbaum E Manstein DJ 《Cellular and molecular life sciences : CMLS》2011,68(16):2751-2767
Dictyostelium discoideum cells produce five dynamin family proteins. Here, we show that dynamin B is the only member of this group of proteins that
is initially produced as a preprotein and requires processing by mitochondrial proteases for formation of the mature protein.
Our results show that dynamin B-depletion affects many aspects of cell motility, cell-cell and cell-surface adhesion, resistance
to osmotic shock, and fatty acid metabolism. The mature form of dynamin B mediates a wide range and unique combination of
functions. Dynamin B affects events at the plasma membrane, peroxisomes, the contractile vacuole system, components of the
actin-based cytoskeleton, and cell adhesion sites. The modulating effect of dynamin B on the activity of the contractile vacuole
system is unique for the Dictyostelium system. Other functions displayed by dynamin B are commonly associated with either classical dynamins or dynamin-related
proteins. 相似文献
72.
Biegel E Schmidt S González JM Müller V 《Cellular and molecular life sciences : CMLS》2011,68(4):613-634
Microbes have a fascinating repertoire of bioenergetic enzymes and a huge variety of electron transport chains to cope with
very different environmental conditions, such as different oxygen concentrations, different electron acceptors, pH and salinity.
However, all these electron transport chains cover the redox span from NADH + H+ as the most negative donor to oxygen/H2O as the most positive acceptor or increments thereof. The redox range more negative than −320 mV has been largely ignored.
Here, we have summarized the recent data that unraveled a novel ion-motive electron transport chain, the Rnf complex, that
energetically couples the cellular ferredoxin to the pyridine nucleotide pool. The energetics of the complex and its biochemistry,
as well as its evolution and cellular function in different microbes, is discussed. 相似文献
73.
Inflammasomes: current understanding and open questions 总被引:2,自引:2,他引:0
Bauernfeind F Ablasser A Bartok E Kim S Schmid-Burgk J Cavlar T Hornung V 《Cellular and molecular life sciences : CMLS》2011,68(5):765-783
The innate immune system relies on its capability to detect invading microbes, tissue damage, or stress via evolutionarily
conserved receptors. The nucleotide-binding domain leucine-rich repeat (NLR)-containing family of pattern recognition receptors
includes several proteins that drive inflammation in response to a wide variety of molecular patterns. In particular, the
NLRs that participate in the formation of a molecular scaffold termed the “inflammasome” have been intensively studied in
past years. Inflammasome activation by multiple types of tissue damage or by pathogen-associated signatures results in the
autocatalytic cleavage of caspase-1 and ultimately leads to the processing and thus secretion of pro-inflammatory cytokines,
most importantly interleukin (IL)-1β and IL-18. Here, we review the current knowledge of mechanisms leading to the activation
of inflammasomes. In particular, we focus on the controversial molecular mechanisms that regulate NLRP3 signaling and highlight
recent advancements in DNA sensing by the inflammasome receptor AIM2. 相似文献
74.
Amiot L Ferrone S Grosse-Wilde H Seliger B 《Cellular and molecular life sciences : CMLS》2011,68(3):417-431
Although the expression of the non-classical HLA class I molecule HLA-G was first reported to be restricted to the fetal–maternal
interface on the extravillous cytotrophoblasts, the distribution of HLA-G in normal tissues appears broader than originally
described. HLA-G expression was found in embryonic tissues, in adult immune privileged organs, and in cells of the hematopoietic
lineage. More interestingly, under pathophysiological conditions HLA-G antigens may be expressed on various types of malignant
cells suggesting that HLA-G antigen expression is one strategy used by tumor cells to escape immune surveillance. In this
article, we will focus on HLA-G expression in cancers of distinct histology and its association with the clinical course of
diseases, on the underlying molecular mechanisms of impaired HLA-G expression, on the immune tolerant function of HLA-G in
tumors, and on the use of membrane-bound and soluble HLA-G as a diagnostic or prognostic biomarker to identify tumors and
to monitor disease stage, as well as on the use of HLA-G as a novel therapeutic target in cancer. 相似文献
75.
76.
77.
New use of BCG for recombinant vaccines 总被引:147,自引:0,他引:147
C K Stover V F de la Cruz T R Fuerst J E Burlein L A Benson L T Bennett G P Bansal J F Young M H Lee G F Hatfull 《Nature》1991,351(6326):456-460
BCG, a live attenuated tubercle bacillus, is the most widely used vaccine in the world and is also a useful vaccine vehicle for delivering protective antigens of multiple pathogens. Extrachromosomal and integrative expression vectors carrying the regulatory sequences for major BCG heat-shock proteins have been developed to allow expression of foreign antigens in BCG. These recombinant BCG strains can elicit long-lasting humoral and cellular immune responses to foreign antigens in mice. 相似文献
78.
Phenotypic differences between alpha beta versus beta T-cell receptor transgenic mice undergoing negative selection 总被引:8,自引:0,他引:8
T-cell differentiation in the thymus is thought to involve a progression from the CD4-CD8- phenotype through CD4+CD8+ intermediates to mature CD4+ or CD8+ cells. There is evidence that during this process T cells bearing receptors potentially reactive to 'self' are deleted by a process termed 'negative selection' One example of this process occurs in mice carrying polymorphic Mls antigens, against which a detectable proportion of T cells are autoreactive. These mice show clonal deletion of thymic and peripheral T-cell subsets that express the autoreactive V beta 3 segment of the T-cell antigen receptor, but at most a two-fold depletion of thymic cells at the CD4+CD8+ stage. By contrast, transgenic mice bearing both alpha and beta chain genes encoding autoreactive receptors recognizing other ligands, show severe depletion of CD4+CD8+ thymocytes as well, suggesting that negative selection occurs much earlier. We report here the Mls 2a/3a mediated elimination of T cells expressing a transgene encoded V beta 3-segment, in T-cell receptor alpha/beta and beta-transgenic mice. Severe depletion of CD4+CD8+ thymocytes is seen only in the alpha/beta chain transgenic mice, whereas both strains delete mature V beta 3 bearing CD4+ and CD8+ T cells efficiently. We conclude that severe CD4+CD8+ thymocyte deletion in alpha/beta transgenic mice results from the premature expression of both receptor chains, and does not reflect a difference in the timing or mechanism of negative selection for Mls antigens as against the allo- and MHC class 1-restricted antigens used in the other studies. 相似文献
79.
80.
董世德 《湘潭大学自然科学学报》1994,(2)
本文论述了ZYS—2阻燃不饱和聚酯树脂的研制,该树脂采用溴素阻燃剂,并利用阻燃剂之间的协同作用,减少了阻燃剂添加量,并且提高了阻燃效果和阻燃材料的物理机械性能. 相似文献