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911.
医疗服务供应链管理模型研究 总被引:1,自引:0,他引:1
在分析医疗服务特点的基础上,建立了基于信息平台的医疗服务供应链管理模型.其中,供应商、医院和患者通过信息平台进行有效沟通,进行需求管理、人力资源管理、医疗服务能力管理、供应商关系管理、医疗服务质量管理和医患关系管理,以及与卫生局、食品药品监督管理局、银行和政府等医疗服务供应链外部的联系.通过CR医院的实证分析,证明了基于信息平台的医疗服务供应链管理模型的有效性和实用性. 相似文献
912.
Steinbusch LK Schwenk RW Ouwens DM Diamant M Glatz JF Luiken JJ 《Cellular and molecular life sciences : CMLS》2011,68(15):2525-2538
Cardiomyocytes use glucose as well as fatty acids for ATP production. These substrates are transported into the cell by glucose
transporter 4 (GLUT4) and the fatty acid transporter CD36. Besides being located at the sarcolemma, GLUT4 and CD36 are stored
in intracellular compartments. Raised plasma insulin concentrations and increased cardiac work will stimulate GLUT4 as well
as CD36 to translocate to the sarcolemma. As so far studied, signaling pathways that regulate GLUT4 translocation similarly
affect CD36 translocation. During the development of insulin resistance and type 2 diabetes, CD36 becomes permanently localized
at the sarcolemma, whereas GLUT4 internalizes. This juxtaposed positioning of GLUT4 and CD36 is important for aberrant substrate
uptake in the diabetic heart: chronically increased fatty acid uptake at the expense of glucose. To explain the differences
in subcellular localization of GLUT4 and CD36 in type 2 diabetes, recent research has focused on the role of proteins involved
in trafficking of cargo between subcellular compartments. Several of these proteins appear to be similarly involved in both
GLUT4 and CD36 translocation. Others, however, have different roles in either GLUT4 or CD36 translocation. These trafficking
components, which are differently involved in GLUT4 or CD36 translocation, may be considered novel targets for the development
of therapies to restore the imbalanced substrate utilization that occurs in obesity, insulin resistance and diabetic cardiomyopathy. 相似文献
913.
914.
Thomae AW Baltin J Pich D Deutsch MJ Ravasz M Zeller K Gossen M Hammerschmidt W Schepers A 《Cellular and molecular life sciences : CMLS》2011,68(22):3741-3756
In eukaryotes, binding of the six-subunit origin recognition complex (ORC) to DNA provides an interactive platform for the
sequential assembly of pre-replicative complexes. This process licenses replication origins competent for the subsequent initiation
step. Here, we analyze the contribution of human Orc6, the smallest subunit of ORC, to DNA binding and pre-replicative complex
formation. We show that Orc6 not only interacts with Orc1–Orc5 but also with the initiation factor Cdc6. Biochemical and imaging
experiments reveal that this interaction is required for licensing DNA replication competent. Furthermore, we demonstrate
that Orc6 contributes to the interaction of ORC with the chaperone protein HMGA1a (high mobility group protein A1a). Binding
of human ORC to replication origins is not specified at the level of DNA sequence and the functional organization of origins
is poorly understood. We have identified HMGA1a as one factor that might direct ORC to AT-rich heterochromatic regions. The
systematic analysis of the interaction between ORC and HMGA1a revealed that Orc6 interacts with the acidic C-terminus of HMGA1a
and also with its AT-hooks. Both domains support autonomous replication if targeted to DNA templates. As such, Orc6 functions
at different stages of the replication initiation process. Orc6 can interact with ORC chaperone proteins such as HMGA1a to
facilitate chromatin binding of ORC and is also an essential factor for pre-RC formation. 相似文献
915.
916.
Zafirova B Wensveen FM Gulin M Polić B 《Cellular and molecular life sciences : CMLS》2011,68(21):3519-3529
NKG2D is one of the most intensively studied immune receptors of the past decade. Its unique binding and signaling properties,
expression pattern, and functions have been attracting much interest within the field due to its potent antiviral and anti-tumor
properties. As an activating receptor, NKG2D is expressed on cells of the innate and adaptive immune system. It recognizes
stress-induced MHC class I-like ligands and acts as a molecular sensor for cells jeopardized by viral infections or DNA damage.
Although the activating functions of NKG2D have been well documented, recent analysis of NKG2D-deficient mice suggests that
this receptor may have a regulatory role during NK cell development. In this review, we will revisit known aspects of NKG2D
functions and present new insights in the proposed influence of this molecule on hematopoietic differentiation. 相似文献
917.
918.
Terhi Vihervaara Riikka-Liisa Uronen Gerd Wohlfahrt Ingemar Björkhem Elina Ikonen Vesa M. Olkkonen 《Cellular and molecular life sciences : CMLS》2011,68(3):537-551
ORP1L is an oxysterol binding homologue that regulates late endosome (LE) positioning. We show that ORP1L binds several oxysterols
and cholesterol, and characterize a mutant, ORP1L Δ560–563, defective in oxysterol binding. While wild-type ORP1L clusters
LE, ORP1L Δ560–563 induces LE scattering, which is reversed by disruption of the endoplasmic reticulum (ER) targeting FFAT
motif, suggesting that it is due to enhanced LE–ER interactions. Endosome motility is reduced upon overexpression of ORP1L.
Both wild-type ORP1L and the Δ560–563 mutant induce the recruitment of both dynactin and kinesin-2 on LE. Most of the LE decorated
by overexpressed ORP1L fail to accept endocytosed dextran or EGF, and the transfected cells display defective degradation
of internalized EGF. ORP1L silencing in macrophage foam cells enhances endosome motility and results in inhibition of [3H]cholesterol efflux to apolipoprotein A-I. These data demonstrate that LE motility and functions in both protein and lipid
transport are regulated by ORP1L. 相似文献
919.
Proline-rich antimicrobial peptides are a group of cationic host defense peptides of vertebrates and invertebrates characterized
by a high content of proline residues, often associated with arginine residues in repeated motifs. Those isolated from some
mammalian and insect species, although not evolutionarily related, use a similar mechanism to selectively kill Gram-negative
bacteria, with a low toxicity to animals. Unlike other types of antimicrobial peptides, their mode of action does not involve
the lysis of bacterial membranes but entails penetration into susceptible cells, where they then act intracellularly. Some
aspects of the transport system and cytoplasmic targets have been elucidated. These features make them attractive both as
anti-infective lead compounds and as a new class of potential cell-penetrating peptides capable of internalising membrane-impermeant
drugs into both bacterial and eukaryotic cells 相似文献
920.
Wesch D Peters C Oberg HH Pietschmann K Kabelitz D 《Cellular and molecular life sciences : CMLS》2011,68(14):2357-2370
Toll-like receptors (TLR) are pattern-recognition receptors that recognize a broad variety of structurally conserved molecules
derived from microbes. The recognition of TLR ligands functions as a primary sensor of the innate immune system, leading to
subsequent indirect activation of the adaptive immunity as well as none-immune cells. However, TLR are also expressed by several
T cell subsets, and the respective ligands can directly modulate their effector functions. The present review summarizes the
recent findings of γδ T cell modulation by TLR ligands. TLR1/2/6, 3, and 5 ligands can act directly in combination with T
cell receptor (TCR) stimulation to enhance cytokine/chemokine production of freshly isolated human γδ T cells. In contrast
to human γδ T cells, murine and bovine γδ T cells can directly respond to TLR2 ligands with increased proliferation and cytokine
production in a TCR-independent manner. Indirect stimulatory effects on IFN-γ production of human and murine γδ T cells via
TLR-ligand activated dendritic cells have been described for TLR2, 3, 4, 7, and 9 ligands. In addition, TLR3 and 7 ligands
indirectly increase tumor cell lysis by human γδ T cells, whereas ligation of TLR8 abolishes the suppressive activity of human
tumor-infiltrating Vδ1 γδ T cells on αβ T cells and dendritic cells. Taken together, these data suggest that TLR-mediated
signals received by γδ T cells enhance the initiation of adaptive immune responses during bacterial and viral infection directly
or indirectly. Moreover, TLR ligands enhance cytotoxic tumor responses of γδ T cells and regulate the suppressive capacity
of γδ T cells. 相似文献