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141.
142.
Walter Rossi Cervi Rubens Augusto Camargo Lamparelli Joaquim Eugênio Abel Seabra Martin Junginger Sierk de Jong Floor van der Hilst 《Global Change Biology Bioenergy》2020,12(2):136-157
It is expected that Brazil could play an important role in biojet fuel (BJF) production in the future due to the long experience in biofuel production and the good agro‐ecological conditions. However, it is difficult to quantify the techno‐economic potential of BJF because of the high spatiotemporal variability of available land, biomass yield, and infrastructure as well as the technological developments in BJF production pathways. The objective of this research is to assess the recent and future techno‐economic potential of BJF production in Brazil and to identify location‐specific optimal combinations of biomass crops and technological conversion pathways. In total, 13 production routes (supply chains) are assessed through the combination of various biomass crops and BJF technologies. We consider temporal land use data to identify potential land availability for biomass production. With the spatial distribution of the land availability and potential yield of biomass crops, biomass production potential and costs are calculated. The BJF production cost is calculated by taking into account the development in the technological pathways and in plant scales. We estimate the techno‐economic potential by determining the minimum BJF total costs and comparing this with the range of fossil jet fuel prices. The techno‐economic potential of BJF production ranges from 0 to 6.4 EJ in 2015 and between 1.2 and 7.8 EJ in 2030, depending on the reference fossil jet fuel price, which varies from 19 to 65 US$/GJ across the airports. The techno‐economic potential consists of a diverse set of production routes. The Northeast and Southeast region of Brazil present the highest potentials with several viable production routes, whereas the remaining regions only have a few promising production routes. The maximum techno‐economic potential of BJF in Brazil could meet almost half of the projected global jet fuel demand toward 2030. 相似文献
143.
On the regulatory properties of deoxycytidylate aminohydrolase 总被引:1,自引:0,他引:1
144.
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146.
Actin carbonylation: from a simple marker of protein oxidation to relevant signs of severe functional impairment. 总被引:6,自引:0,他引:6
I Dalle-Donne R Rossi D Giustarini N Gagliano L Lusini A Milzani P Di Simplicio R Colombo 《Free radical biology & medicine》2001,31(9):1075-1083
The number of protein-bound carbonyl groups is an established marker of protein oxidation. Recent evidence indicates a significant increase in actin carbonyl content in both Alzheimer's disease brains and ischemic hearts. The enhancement of actin carbonylation, causing the disruption of the actin cytoskeleton and the loss of the barrier function, has also been found in human colonic cells after exposure to hypochlorous acid (HOCl). Here, the effects of oxidation induced by HOCl on purified actin are presented. Results show that HOCl causes a rapidly increasing yield of carbonyl groups. However, when carbonylation becomes evident, some Cys and Met residues have been already oxidized. Covalent intermolecular cross-linking as well as some noncovalent aggregation of carbonylated actin have been found. The covalent cross-linking, unaffected by reducing and denaturing agents, parallels an increase in dityrosine fluorescence. Moreover, HOCl-mediated oxidation induces the progressive disruption of actin filaments and the inhibition of F-actin formation. The molar ratios of HOCl to actin that lead to inhibition of actin polymerization seem to have effect only on cysteines and methionines. The process that involves oxidation of amino acid side chains with formation of a carbonyl group would occur at an extent of oxidative insult higher than that causing the oxidation of some critical amino acid residues. Therefore, the increase in actin content of carbonyl groups found in vivo would indicate drastic oxidative modification leading to drastic functional impairments. 相似文献
147.
Ward C Dransfield I Murray J Farrow SN Haslett C Rossi AG 《Journal of immunology (Baltimore, Md. : 1950)》2002,168(12):6232-6243
Many inflammatory mediators retard granulocyte apoptosis. Most natural PGs studied herein (e.g., PGE(2), PGA(2), PGA(1), PGF(2 alpha)) either delayed apoptosis or had no effect, whereas PGD(2) and its metabolite PGJ(2) selectively induced eosinophil, but not neutrophil apoptosis. This novel proapoptotic effect does not appear to be mediated via classical PG receptor ligation or by elevation of intracellular cAMP or Ca(2+). Intriguingly, the sequential metabolites Delta(12)PGJ(2) and 15-deoxy-Delta(12,) Delta(14)-PGJ(2) (15dPGJ(2)) induced caspase-dependent apoptosis in both granulocytes, an effect that did not involve de novo protein synthesis. Despite the fact that Delta(12)PGJ(2) and 15dPGJ(2) are peroxisome proliferator-activated receptor-gamma (PPAR-gamma) activators, apoptosis was not mimicked by synthetic PPAR-gamma and PPAR-alpha ligands or blocked by an irreversible PPAR-gamma antagonist. Furthermore, Delta(12)PGJ(2) and 15dPGJ(2) inhibited LPS-induced I kappa B alpha degradation and subsequent inhibition of neutrophil apoptosis, suggesting that apoptosis is mediated via PPAR-gamma-independent inhibition of NF-kappa B activation. In addition, we show that TNF-alpha-mediated loss of cytoplasmic I kappa B alpha in eosinophils is inhibited by 15dPGJ(2) in a concentration-dependent manner. The selective induction of eosinophil apoptosis by PGD(2) and PGJ(2) may help define novel therapeutic pathways in diseases in which it would be desirable to specifically remove eosinophils but retain neutrophils for antibacterial host defense. The powerful proapoptotic effects of Delta(12)PGJ(2) and 15dPGJ(2) in both granulocyte types suggest that these natural products control the longevity of key inflammatory cells and may be relevant to understanding the control and resolution of inflammation. 相似文献
148.
149.
Raimondi S Roncaglia L De Lucia M Amaretti A Leonardi A Pagnoni UM Rossi M 《Applied microbiology and biotechnology》2009,81(5):943-950
Twenty-two strains of Bifidobacterium, representative of eight major species of human origin, were screened for their ability to transform the isoflavones daidzin
and daidzein. Most of the strains released the aglycone from daidzin and 12 gave yields higher than 90%. The kinetics of growth,
daidzin consumption, and daidzein production indicated that the hydrolytic activity occurred during the growth. The supernatant
of the majority of the strains did not release the aglycone from daidzin, suggesting that cell-associated β-glucosidases (β-Glu)
are mainly responsible for the metabolism of soybean glyco-conjugates. Cell-associated β-Glu was mainly intracellular and
significantly varied among the species and the strains. The lack of β-Glu was correlated with the inability to hydrolyze daidzin.
Although S-equol production by anaerobic intestinal bacteria has been established, information on S-equol-producing bifidobacteria
is contradictory. In this study, 22 bifidobacteria failed to transform daidzein into reduced metabolites under all the experimental
conditions, excluding any role in the reductive pathway of daidzein toward the production of S-equol. These results suggest
that selected probiotic strains of Bifidobacterium can be used to speed up the release of daidzein, improving its bioavailability for absorption by colonic mucosa and/or biotransformation
to S-equol by other intestinal microorganisms. 相似文献
150.
Giovanna Poce Robert H. Bates Salvatore Alfonso Martina Cocozza Giulio Cesare Porretta Lluís Ballell Joaquin Rullas Fátima Ortega Alessandro De Logu Emanuela Agus Valentina La Rosa Maria Rosalia Pasca Edda De Rossi Baojie Wae Scott G. Franzblau Fabrizio Manetti Maurizio Botta Mariangela Biava 《PloS one》2013,8(2)
1,5-Diphenyl pyrroles were previously identified as a class of compounds endowed with high in vitro efficacy against M. tuberculosis. To improve the physical chemical properties and drug-like parameters of this class of compounds, a medicinal chemistry effort was undertaken. By selecting the optimal substitution patterns for the phenyl rings at N1 and C5 and by replacing the thiomorpholine moiety with a morpholine one, a new series of compounds was produced. The replacement of the sulfur with oxygen gave compounds with lower lipophilicity and improved in
vitro microsomal stability. Moreover, since the parent compound of this family has been shown to target MmpL3, mycobacterial mutants resistant to two compounds have been isolated and characterized by sequencing the mmpL3 gene; all the mutants showed point mutations in this gene. The best compound identified to date was progressed to dose-response studies in an acute murine TB infection model. The resulting ED99 of 49 mg/Kg is within the range of commonly employed tuberculosis drugs, demonstrating the potential of this chemical series. The in vitro and in vivo target validation evidence presented here adds further weight to MmpL3 as a druggable target of interest for anti-tubercular drug discovery. 相似文献