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991.
Moraes JC Amaral ME Picardi PK Calegari VC Romanatto T Bermúdez-Echeverry M Chiavegatto S Saad MJ Velloso LA 《FEBS letters》2006,580(19):4625-4631
TNF-alpha acts on the hypothalamus modulating food intake and energy expenditure through mechanisms incompletely elucidated. Here, we explore the hypothesis that, to modulate insulin-induced anorexigenic signaling in hypothalamus, TNF-alpha requires the synthesis of NO. TNF-alpha activates signal transduction through JNK and p38 in hypothalamus, peaking at 10(-8) M. This is accompanied by the induction of expression of the inducible and neuronal forms of NOS, in both cases peaking at 10(-12) M. In addition, TNF-alpha stimulates NOS catalytic activity. Pre-treatment with TNF-alpha at a low dose (10(-12) M) inhibits insulin-dependent anorexigenic signaling, and this effect is abolished in iNOS but not in nNOS knockout mice. 相似文献
992.
The comparative phylogeographic study of the maned sloth (Bradypus torquatus) and the three-toed sloth (Bradypus variegatus) was performed using a segment of mitochondrial DNA (mtDNA) control region. We examined 19 B. torquatus from two regions and 47 B. variegatus from three distant regions of Atlantic forest. This first characterization of molecular diversity indicates a great diversity
(B. torquatus: h = 0.901 ± 0.039 and π = 0.012 ± 0.007; B. variegatus: h = 0.699 ± 0.039 and π = 0.010 ± 0.006) and very divergent mitochondrial lineages within each sloth species. The different sampled regions carry
distinct and non-overlapping sets of mtDNA haplotypes and are genetically divergent. This phylogeographic pattern may be characteristic
of sloth species. In addition, we infer that two main phylogeographic groups exist in the Atlantic forest representing a north
and south distinct divergence. 相似文献
993.
Kamakura M Morisawa K Komi H Tomatani A Saito F Konishi Y Jin Y Manabe T Kuroda M Imai S Mizuguchi H Taniguchi T 《Biochemical and biophysical research communications》2006,349(4):1372-1377
To elucidate the regulation of IL-27p28 gene, we analyzed the promoter region of the gene in DC2.4 cells with or without lipopolysaccharide (LPS)-treatment. The results indicate that a region (-648 to -364) of p28 promoter was responsible for LPS-induction. EMSA with DNA probes within the region reveals that binding of GATA motif bound proteins was decreased by LPS-treatment. We identified one of the proteins as non-POU domain-containing octamer binding protein (NonO). Taken together, LPS-induced activation of IL-27p28 gene can be accounted for by the displacement of bound NonO protein from the IL-27p28 promoter. 相似文献
994.
995.
The secondary structure of pressure- and temperature-induced aggregates of equine serum albumin studied by FT-IR spectroscopy 总被引:1,自引:0,他引:1
The protein aggregation is divided into amyloid fibrils and amorphous aggregates. Amyloid fibrils are composed of the 3-dimensional ordered structure and are bound to thioflavin T and Congo red dyes. The amorphous aggregates with the disordered structure do not bind to these dyes. We have investigated the pressure- and heat-induced aggregates of equine serum albumin (ESA) from the secondary structural viewpoint using FT-IR spectroscopy. We show the secondary structural differences between heat- and pressure-induced aggregates of ESA. The heat-induced irreversible aggregates of ESA are composed of the intermolecular beta-sheet structure without binding thioflavie T and Congo red to be amorphous form. On the other hand, the pressure-induced reversible aggregates are composed of the random structure to be also amorphous form. From the comparison of pressure effects on ESA in native and reducing conditions of disulfide bridges, we demonstrate that the restriction of structural flexibility by disulfide bridges is an important factor for the reversibility of the pressure-induced aggregation. 相似文献
996.
997.
Camila D. Coimbra Raquel D. Rufino Juliana M. Luna Leonie A. Sarubbo 《Current microbiology》2009,58(3):245-251
In practical bioremediation of petroleum pollution, treatment systems often use soil, sand, and other aquifer porous media
besides water solutions. The distribution of the microbial cell also plays an important role in the whole process of bioremediation;
therefore, the adhesion ability of cells to porous media is one of the key factors influencing the efficiency of treatment.
The probable modes of hydrocarbon uptake in cells of Candida were studied based on data for cell hydrophobicity, emulsifying activity, surface tension, and interfacial tension of the
cell-free culture medium. Six Candida strains were cultivated in insoluble and soluble substrates for 144 h, including n-hexadecane, soybean oil, ground-nut oil refinery residue, corn steep liquor, and glucose. The results obtained showed the
potential of yeasts for application in the removal of hydrophobic compounds. Depending the strain and substrate used the adhesion
ability of yeast cells and the production of surfactants and emulsifiers can take place simultaneously, thus increasing the
efficiency of bioremediation treatment of petroleum pollution. The application of crude biosurfactants separated from the
yeast cells was also demonstrated by tests of removal of petroleum and the derivate motor oil adsorbed in sand samples. Biosurfactants
produced in low-cost medium were able to remove 90% of the hydrophobic contaminants. 相似文献
998.
Daniele Chaves‐Moreira Olga M. Chaim Youssef B. Sade Kátia S. Paludo Luiza H. Gremski Lucélia Donatti Juliana de Moura Oldemir C. Mangili Waldemiro Gremski Rafael B. da Silveira Andrea Senff‐Ribeiro Silvio S. Veiga 《Journal of cellular biochemistry》2009,107(4):655-666
Brown spiders have world‐wide distribution and are the cause of health problems known as loxoscelism. Necrotic cutaneous lesions surrounding the bites and less intense systemic signs like renal failure, DIC, and hemolysis were observed. We studied molecular mechanism by which recombinant toxin, biochemically characterized as phospholipase‐D , causes direct hemolysis (complement independent). Human erythrocytes treated with toxin showed direct hemolysis in a dose‐dependent and time‐dependent manner, as well as morphological changes in cell size and shape. Erythrocytes from human, rabbit, and sheep were more susceptible than those from horse. Hemolysis was not dependent on ABO group or Rhesus system. Confocal and FACS analyses using antibodies or GFP‐phospholipase‐D protein showed direct toxin binding to erythrocytes membrane. Moreover, toxin‐treated erythrocytes reacted with annexin‐V and showed alterations in their lipid raft profile. Divalent ion chelators significantly inhibited hemolysis evoked by phospholipase‐D , which has magnesium at the catalytic domain. Chelators were more effective than PMSF (serine‐protease inhibitor) that had no effect on hemolysis. By site‐directed mutation at catalytic domain (histidine 12 by alanine), hemolysis and morphologic changes of erythrocytes (but not the toxin's ability of membrane binding) were inhibited, supporting that catalytic activity is involved in hemolysis and cellular alterations but not toxin cell binding. The results provide evidence that L. intermedia venom phospholipase‐D triggers direct human blood cell hemolysis in a catalytic‐dependent manner. J. Cell. Biochem. 107: 655–666, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
999.
1000.
Linda Styer Caldas Luana de Lima Machado Sarah Christina Caldas Marcelo Lattarulo Campos Juliana Araújo Caldas Richard Persons Pharis Adaucto Bellarmino Pereira-Netto 《Trees - Structure and Function》2009,23(6):1229-1235
Shoot elongation of Hancornia speciosa, an endangered tree from the Brazilian savannah “Cerrado”, is very slow, thus limiting nursery production of plants. Gibberellins
(GAs) A1, A3, and A5, and two inhibitors of GA biosynthesis, trinexapac-ethyl and ancymidol were applied to shoots of Hancornia seedlings. GA1 and GA3 significantly stimulated shoot elongation, while GA5 had no significant effect. Trinexapac-ethyl and ancymidol, both at 100 μg per seedling, inhibited shoot elongation up to
45 days after treatment, though the effect was statistically significant only for ancymidol. Somewhat surprisingly, exogenous
GA3 more effectively stimulated shoot elongation in SD-grown plants, than in LD-grown plants. The results from exogenous application
of GAs and inhibitors of GA biosynthesis imply that Hancornia shoot growth is controlled by GAs, and that level of endogenous growth-active GAs is likely to be the limiting factor for
shoot elongation in Hancornia. Application of GAs thus offer a practical method for nursery production of Hancornia seedlings for outplanting into the field. 相似文献