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71.
Terry A. Potter Suzanne M. Watt Antony W. Burgess Ian F. C. McKenzie 《Immunogenetics》1979,8(1):461-473
Serological analysis of highly purified (>97%) mouse peritoneal exudate neutrophils using a protein-A rosetting technique, showed that these cells possessed the surface phenotype: Ig–, Thy-1–, Ly-1–, Ly-2–, Ly-3–, Ly-4+, Ly-5+, Ly-6+, Ly-7–, Ia–, FcR+ and C3R+. 相似文献
72.
Aditya Nath Jha Vipin Kumar Singh Namrata Kumari Ashish Singh Justin Antony Hoang van Tong Sakshi Singh Sudhanshu S. Pati Pradeep K. Patra Rajender Singh Nguyen L. Toan Le H. Song Amal Assaf Iara J. T. Messias–Reason Thirumalaisamy P. Velavan Lalji Singh Kumarasamy Thangaraj 《PloS one》2012,7(10)
Background
Interleukin 4 (IL-4) is an anti-inflammatory cytokine, which regulates balance between TH1 and TH2 immune response, immunoglobulin class switching and humoral immunity. Polymorphisms in this gene have been reported to affect the risk of infectious and autoimmune diseases.Methods
We have analyzed three regulatory IL-4 polymorphisms; -590C>T, -34C>T and 70 bp intron-3 VNTR, in 4216 individuals; including: (1) 430 ethnically matched case-control groups (173 severe malaria, 101 mild malaria and 156 asymptomatic); (2) 3452 individuals from 76 linguistically and geographically distinct endogamous populations of India, and (3) 334 individuals with different ancestry from outside India (84 Brazilian, 104 Syrian, and 146 Vietnamese).Results
The -590T, -34T and intron-3 VNTR R2 alleles were found to be associated with reduced malaria risk (P<0.001 for -590C>T and -34C>T, and P = 0.003 for VNTR). These three alleles were in strong LD (r2>0.75) and the TTR2 (-590T, -34T and intron-3 VNTR R2) haplotype appeared to be a susceptibility factor for malaria (P = 0.009, OR = 0.552, 95% CI = 0.356 –0.854). Allele and genotype frequencies differ significantly between caste, nomadic, tribe and ancestral tribal populations (ATP). The distribution of protective haplotype TTR2 was found to be significant (χ2 3 = 182.95, p-value <0.001), which is highest in ATP (40.5%); intermediate in tribes (33%); and lowest in caste (17.8%) and nomadic (21.6%).Conclusions
Our study suggests that the IL-4 polymorphisms regulate host susceptibility to malaria and disease progression. TTR2 haplotype, which gives protection against malaria, is high among ATPs. Since they inhabited in isolation and mainly practice hunter-gatherer lifestyles and exposed to various parasites, IL-4 TTR2 haplotype might be under positive selection. 相似文献73.
This article describes a quick and easy method for determining relative binding affinities between proteins and metal ions. The method is based on separating unbound metal ions from metal ions bound to protein by ultrafiltration using microcentrifuge ultrafiltration units. Bovine serum albumin (BSA) was used as the test protein and the relative affinity towards divalent metal ions was found to be Cu2+>Zn2+>Cd2+>Pb2+>Ni2+>Co2+, which corresponds to the relative orders reported in the literature. 相似文献
74.
B J Thiele J Fleming K Kasturi J O'Prey E Black J Chester S M Rapoport P R Harrison 《Gene》1987,57(1):111-119
We report the isolation of cDNA recombinants representing part of the rabbit reticulocyte (immature red blood cell, RBC) lipoxygenase (LOX) mRNA. One cDNA predicts an amino acid (aa) sequence matching exactly the unique N-terminal 30-aa sequence of the purified enzyme. Further, the reticulocyte mRNA, hybrid-selected by this recombinant, can be translated in vitro to give a polypeptide that comigrates with the purified reticulocyte LOX and is recognized by affinity-purified anti-RBC LOX polyclonal antibodies. Southern blotting experiments hybridising the RBC LOX cDNAs available to total rabbit genomic DNA digested with various restriction enzymes gives a fairly simple hybridisation pattern under moderate stringency conditions: moreover, the same pattern is obtained with a cloned fragment of genomic DNA containing the RBC LOX gene. This indicates that the RBC LOX gene is unique in the genome and seems not to be very closely related to the genes encoding the other tissue LOXs. We also show by Northern transfer/hybridisation experiments that the RBC LOX mRNA is expressed only in the red cell lineage but not in white blood cells (bone marrow or spleen) or in other non-erythroid cells tested (e.g., brain and lung). 相似文献
75.
The proteins of the smooth and rough endoplasmic reticulum from fetal, immature, and adult male rats were compared after incorporation of two radioactively labeled precursors, 14C-labeled amino acids and δ-aminolevulinic acid-3H by means of gel electrophoresis. The labeling patterns indicated that protein components present in two major electrophoretic bands underwent significant synthesis in fetal tissue while three actively incorporating protein bands were noted in adult tissue. Although the uptake of the amino acids-14C decreased for the smooth and rough elements of the endoplasmic reticulum as a whole during liver development, the qualitative patterns were not significantly different in adult and fetal livers. The over-all incorporation (disintegrations per minute per milligram protein) of the heme precursor into the smooth and rough elements also did not change with development. However, a change was noted in the distributional electrophoretic patterns with development. The estimation of molecular weight (by disc electrophoresis) and the incorporation of the heme precursor suggested the similarity of the two major protein bands to cytochrome P-450 and cytochrome b5, components of the endoplasmic reticulum, thought to be involved in the mixed-function oxidase system. The evidence indicated that in fetal liver, at a time when the oxidase capability was low, the amino acid incorporation into these two protein groups was the same as in the adult. The incorporation of the heme moiety, however, was different, decreasing in the cytochrome b5 region and increasing in the cytochrome P-450 region during development. These results correlate with the increase in oxidase activity associated with liver development. 相似文献
76.
Rajesh Abraham Jacob Cassandra R. Edgar Jrmie Prvost Steven M. Trothen Antony Lurie Mitchell J. Mumby Alexa Galbraith Frank Kirchhoff S.M. Mansour Haeryfar Andrs Finzi Jimmy D. Dikeakos 《The Journal of biological chemistry》2021,297(3)
Prolonged immune activation drives the upregulation of multiple checkpoint receptors on the surface of virus-specific T cells, inducing their exhaustion. Reversing HIV-1-induced T cell exhaustion is imperative for efficient virus clearance; however, viral mediators of checkpoint receptor upregulation remain largely unknown. The enrichment of checkpoint receptors on T cells upon HIV-1 infection severely constrains the generation of an efficient immune response. Herein, we examined the role of HIV-1 Nef in mediating the upregulation of checkpoint receptors on peripheral blood mononuclear cells. We demonstrate that the HIV-1 accessory protein Nef upregulates cell surface levels of the checkpoint receptor T-cell immunoglobulin mucin domain-3 (Tim-3) and that this is dependent on Nef''s dileucine motif LL164/165. Furthermore, we used a bimolecular fluorescence complementation assay to demonstrate that Nef and Tim-3 form a complex within cells that is abrogated upon mutation of the Nef dileucine motif. We also provide evidence that Nef moderately promotes Tim-3 shedding from the cell surface in a dileucine motif–dependent manner. Treating HIV-1-infected CD4+ T cells with a matrix metalloprotease inhibitor enhanced cell surface Tim-3 levels and reduced Tim-3 shedding. Finally, Tim-3-expressing CD4+ T cells displayed a higher propensity to release the proinflammatory cytokine interferon-gamma. Collectively, our findings uncover a novel mechanism by which HIV-1 directly increases the levels of a checkpoint receptor on the surface of infected CD4+ T cells. 相似文献
77.
Extraction of whole lobes of normal rat liver with dimethyl sulphoxide (DMSO) under N2 gives extracts which contain 5—10 μmol/l·O?2 (50-100 nmol·O?2 per 10 ml extract per 4 g liver; 1.25-2.50 nmol·O?2 per millilitre per gram liver). Evidence for ·O?2 in the extracts is given by: (1) electron spin resonance signals (ESR), (2) differential pulse polarography (DPP), (3) chemiluminescence (CL), and (4) nitroblue tetrazolium reduction (NBT). All tests yield results identical with those obtained with authentic ·O?2. Extraction of ·O?2 is enhanced by tetrabutyl ammonium ion, and is maximal at 1-3 min. These results raise the possibility that substantial amounts of ·O?2 are normally sequestered in protective membranous sites in vivo. 相似文献
78.
Alterations in the binding of transforming growth factor-beta (TGF-beta) to the MOSER human colon carcinoma cell line caused by N,N-dimethylformamide (DMF) or extracellular matrix (ECM) were examined. DMF induced a more differentiated phenotype in the MOSER cells and resulted in a twofold increase in TGF-beta binding to the cells. This was due to an increase in receptor number with no significant alteration in the KD. The extent of increased TGF-beta binding was dependent on the dose and time of exposure to DMF. Upon removal of DMF, the receptor level returned to that of untreated cells within 6 hr. The binding of TGF-beta 1 and TGF-beta 2 to the cells was increased equally. Despite this increase in TGF-beta binding in the presence of DMF, the sensitivity of the MOSER cells to the growth inhibitory effects of TGF-beta was unaltered. Growth of the MOSER cells on ECM derived from a well-differentiated colon cell line increased the TGF-beta receptor number twofold without altering the KD. No change was observed if the MOSER cells were grown on ECM derived from a poorly differentiated cell line. While no alteration in sensitivity to TGF-beta was observed on cells grown in the presence of DMF, MOSER cells grown on the ECM derived from well-differentiated colon carcinoma cell lines were twofold more sensitive to the growth inhibitory effects of TGF-beta. These results indicated that growth conditions which resulted in a more differentiated phenotype resulted in an increase in the cellular receptors for TGF-beta. 相似文献
79.
Christine M. Gross Ruslan Rafikov Sanjiv Kumar Saurabh Aggarwal P. Benson Ham III Mary Louise Meadows Mary Cherian-Shaw Archana Kangath Supriya Sridhar Rudolf Lucas Stephen M. Black 《PloS one》2015,10(3)
Lipopolysaccharide (LPS) derived from the outer membrane of gram-negative bacteria induces acute lung injury (ALI) in mice. This injury is associated with lung edema, inflammation, diffuse alveolar damage, and severe respiratory insufficiency. We have previously reported that LPS-mediated nitric oxide synthase (NOS) uncoupling, through increases in asymmetric dimethylarginine (ADMA), plays an important role in the development of ALI through the generation of reactive oxygen and nitrogen species. Therefore, the focus of this study was to determine whether mice deficient in endothelial NOS (eNOS-/-) are protected against ALI. In both wild-type and eNOS-/- mice, ALI was induced by the intratracheal instillation of LPS (2 mg/kg). After 24 hours, we found that eNOS-/-mice were protected against the LPS mediated increase in inflammatory cell infiltration, inflammatory cytokine production, and lung injury. In addition, LPS exposed eNOS-/- mice had increased oxygen saturation and improved lung mechanics. The protection in eNOS-/- mice was associated with an attenuated production of NO, NOS derived superoxide, and peroxynitrite. Furthermore, we found that eNOS-/- mice had less RhoA activation that correlated with a reduction in RhoA nitration at Tyr34. Finally, we found that the reduction in NOS uncoupling in eNOS-/- mice was due to a preservation of dimethylarginine dimethylaminohydrolase (DDAH) activity that prevented the LPS-mediated increase in ADMA. Together our data suggest that eNOS derived reactive species play an important role in the development of LPS-mediated lung injury. 相似文献
80.
Kim Y. C. Fung Bruce Tabor Michael J. Buckley Ilka K. Priebe Leanne Purins Celine Pompeia Gemma V. Brierley Trevor Lockett Peter Gibbs Jeanne Tie Paul McMurrick James Moore Andrew Ruszkiewicz Edouard Nice Timothy E. Adams Antony Burgess Leah J. Cosgrove 《PloS one》2015,10(3)