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81.
82.
Predation on coral spawn by planktivorous fish 总被引:1,自引:1,他引:0
The stomach contents of three species of coral reef fish were examined for changes in diet during the annual mass spawning of scleractinian corals on the Great Barrier Reef, Australia. Acanthochromis polyacanthus, Abudefduf bengalensis (Pomacentridae), and Caesio cuning (Caesionidae) were collected before and immediately after the coral spawning to determine whether the composition of the diet changed after the mass coral spawning. The diet of Caesio cuning did not change. The stomach contents of Acanthochromis and Abudefduf showed that these fish: (1) switched from an omnivorous diet to one consisting predominantly of coral spawn, and (2) that they appeared satiated with stomachs >90% full when coral spawn was present in the water column. Fish predation during coral spawning may be an important source of larval coral mortality. 相似文献
83.
W E Burkholder 《Journal of economic entomology》1966,59(5):1110-1112
84.
Natalia Soriano-Sarabia Nancie M. Archin Rosalie Bateson Noelle P. Dahl Amanda M. Crooks JoAnn D. Kuruc Carolina Garrido David M. Margolis 《PLoS pathogens》2015,11(10)
Eradication of HIV infection will require the identification of all cellular reservoirs that harbor latent infection. Despite low or lack of CD4 receptor expression on Vδ2 T cells, infection of these cells has previously been reported. We found that upregulation of the CD4 receptor may render primary Vδ2 cells target for HIV infection in vitro and we propose that HIV-induced immune activation may allow infection of γδ T cells in vivo. We assessed the presence of latent HIV infection by measurements of DNA and outgrowth assays within Vδ2 cells in 18 aviremic patients on long-standing antiretroviral therapy. In 14 patients we recovered latent but replication-competent HIV from highly purified Vδ2 cells demonstrating that peripheral Vδ2 T cells are a previously unrecognized reservoir in which latent HIV infection is unexpectedly frequent. 相似文献
85.
86.
JoAnn C. Radway Jorge W. Santo-Domingo Terry C. Hazen Edward W. Wilde 《Biotechnology letters》1998,20(7):663-666
Foam embedded Burkholderia cepacia G4 removed up to 80 % and 60 % of a 3 mg/l solution of trichloroethylene (TCE) and a 2 mg/l solution of benzene, respectively. Removal of TCE and benzene decreased more than 50% when readily metabolizable carbon sources were present. TCE degradative activity was observed with G4 cells induced with phenol or benzene prior or after immobilization of cells. © Rapid Science Ltd. 1998 相似文献
87.
JoAnn S. Roberts Chao Ma Sarah Y.T. Robertson Stephen Kang Christiana S. Han Sophie X. Deng Jie J. Zheng 《Biochemistry and Biophysics Reports》2022
Etodolac is an FDA-approved nonsteroidal anti-inflammatory drug (NSAID) used to treat a variety of inflammatory diseases. The drug is administered as a racemate (50/50 mixture of R- and S- enantiomers), however, studies have shown that the two enantiomers have distinct biologic and pharmacokinetic differences. Wnt signaling, which plays key roles in cell proliferation, polarity, and differentiation, has been shown to be inhibited by R-etodolac; however, comparative analyses of R- and S-etodolac in this function have not been conducted. We used in silico molecular docking and TOPflash functional biologic assays to compare R- and S-enantiomers effect on Wnt signaling inhibition. Further, we used a cultivated limbal stem epithelial cell (cLSCs) model to investigate enantiospecific changes in the colony-forming efficiency (CFE) of cLSCs. The data shows that R-etodolac is a more potent inhibitor of Wnt signaling. In addition, consistently, while both enantiomers demonstrate a dose-dependent decrease in CFE of cLSCs, R-etodolac is a more potent inhibitor. 相似文献
88.
Frahm MA Picking RA Kuruc JD McGee KS Gay CL Eron JJ Hicks CB Tomaras GD Ferrari G 《Journal of immunology (Baltimore, Md. : 1950)》2012,188(9):4289-4296
Previous studies have revealed that HIV-infected individuals possess circulating CD4(+)CD8(+) double-positive (DP) T cells specific for HIV Ags. In the present study, we analyzed the proliferation and functional profile of circulating DP T cells from 30 acutely HIV-infected individuals and 10 chronically HIV-infected viral controllers. The acutely infected group had DP T cells that showed more proliferative capability and multifunctionality than did both their CD4(+) and CD8(+) T cells. DP T cells were found to exhibit greater proliferation and higher multifunctionality compared with CD4 T cells in the viral controller group. The DP T cell response represented 16% of the total anti-HIV proliferative response and >70% of the anti-HIV multifunctional response in the acutely infected subjects. Proliferating DP T cells of the acutely infected subjects responded to all HIV Ag pools with equal magnitude. Conversely, the multifunctional response was focused on the pool representing Nef, Rev, Tat, VPR, and VPU. Meanwhile, the controllers' DP T cells focused on Gag and the Nef, Rev, Tat, VPR, and VPU pool for both their proliferative and multifunctional responses. Finally, we show that the presence of proliferating DP T cells following all HIV Ag stimulations is well correlated with proliferating CD4 T cells whereas multifunctionality appears to be largely independent of multifunctionality in other T cell compartments. Therefore, DP T cells represent a highly reactive cell population during acute HIV infection, which responds independently from the traditional T cell compartments. 相似文献
89.
The CXCL12/CXCR4 signaling axis plays an important role in human health and disease; however, the molecular mechanisms mediating CXCR4 signaling remain poorly understood. Ubiquitin modification of CXCR4 by the E3 ubiquitin ligase AIP4 is required for lysosomal sorting and degradation, which is mediated by the endosomal sorting complex required for transport (ESCRT) machinery. CXCR4 sorting is regulated by an interaction between endosomal localized arrestin-2 and STAM-1, an ESCRT-0 component. Here, we report a novel role for AIP4 and STAM-1 in regulation of CXCR4 signaling that is distinct from their function in CXCR4 trafficking. Depletion of AIP4 and STAM-1 by siRNA caused significant inhibition of CXCR4-induced ERK-1/2 activation, whereas overexpression of these proteins enhanced CXCR4 signaling. We further show that AIP4 and STAM-1 physically interact and that the proline-rich region in AIP4 and the SH3 domain in STAM-1 are essential for the interaction. Overexpression of an AIP4 catalytically inactive mutant and a mutant that shows poor binding to STAM-1 fails to enhance CXCR4-induced ERK-1/2 signaling, as compared with wild-type AIP4, suggesting that the interaction between AIP4 and STAM-1 and the ligase activity of AIP4 are essential for ERK-1/2 activation. Remarkably, a discrete subpopulation of AIP4 and STAM-1 resides in caveolar microdomains with CXCR4 and appears to mediate ERK-1/2 signaling. We propose that AIP4-mediated ubiquitination of STAM-1 in caveolae coordinates activation of ERK-1/2 signaling. Thus, our study reveals a novel function for ubiquitin in the regulation of CXCR4 signaling, which may be broadly applicable to other G protein-coupled receptors. 相似文献
90.
Eric Burkholder 《Inorganica chimica acta》2006,359(1):261-266
The hydrothermal reaction of CuBr2 and tpyprz in the presence of NH4VO3 and HF for 72 h at 170 °C provided [(tpyprz)3Cu10Br10] (1) in 20% yield. The two-dimensional structure of 1 may be described as Cu(I)-tpyprz chains, linked through {Cu4Br5}− clusters in the ac-plane and decorated with {Cu3Br5}2− clusters projecting from one face of the layer in the b-direction. The Cu(I) sites exhibit distorted trigonal coordination {CuBr3} and distorted tetrahedral geometries, {CuBr2N2} and {CuN4}. Crystal data for 1: monoclinic space group C2, a = 12.7561(8) Å, b = 19.359(1) Å, c = 15.860(1) Å, β = 97.178(1)°, V = 3885.8(4) Å3, Z = 2, Dcalc = 2.222 g cm−3, μ(Mo Kα) = 78.75 cm−1. 相似文献