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991.
Experimental manipulation of tail ornament size affects the hematocrit of male barn swallows (Hirundo rustica) 总被引:2,自引:0,他引:2
Nicola Saino José Javier Cuervo Marco Krivacek Florentino de Lope Anders Pape Møller 《Oecologia》1997,110(2):186-190
Ornamental tail feathers of male barn swallows (Hirundo rustica) confer an advantage in sexual selection because long-tailed males are preferred by females. However, the size of tail ornaments
exceeds the natural selection optimum and males are predicted to pay an energetic cost for flying, directly related to tail
length. An increase in hematocrit is an adaptive response to enhance oxygen uptake, for example during periods of intense
locomotory activity. In this study, we analyzed the effect of experimental manipulation of tail length on the hematocrit of
male barn swallows from an Italian and a Spanish population. We predicted that the natural decrease in hematocrit during the
breeding season would be reduced by experimental elongation and enhanced by experimental shortening of tail ornaments. The
results showed that the decrease in hematocrit was significantly different among tail treatments, and tail-elongated males
had the smallest hematocrit reduction. In Italy, the hematocrit of tail-elongated males did not change after tail manipulation,
while that of two control groups and tail-shortened males decreased. A comparatively high hematocrit in males with experimentally
enlarged tail ornaments may be a response to increased energetic requirements and, hence, to oxygen demands for flying imposed
by their tail morphology.
Received: 22 June 1996 / Accepted: 23 October 1996 相似文献
992.
Nicola Maruotti Addolorata Corrado Anna Neve Francesco Paolo Cantatore 《Journal of cellular physiology》2013,228(7):1428-1432
Wnt signaling plays a key role in several physiological and pathological aspects. Even if Wnt signal was first described more than 20 years ago, its role in systemic effects, such as angiogenesis and vascular disorders, bone biology, autoimmune diseases, neurological diseases, and neoplastic disorders, was only recently emerged through the use of animal and in vitro models. Moreover, Wnt signaling inhibitors, such as DKK‐1, may be advantageously considered targets for the treatment of several diseases, including osteoporosis, vascular diseases, inflammatory diseases, neurological diseases, and cancer. Nevertheless, further studies are required to provide a complete understanding of this complex signaling pathway, and especially of its role in human diseases, considering the possible advantageous effects of Wnt signaling inhibitors on the progression of disease conditions. J. Cell. Physiol. 228: 1428–1432, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
993.
Nicola Tannenbaum 《American anthropologist》1984,86(4):927-942
Sahlins's "Chayanov's Rule"–the more consumers each worker has to support the more work each worker does-has characterized Chayanov's analysis for most anthropologists. I examine the relationship between the consumer/worker ratio and product per worker for the Shan community of Thongmakhsan in northwestern Thailand. Since there is no systematic relationship between these variables even when the population is divided into production strategy groups, I go on to examine the relationship between Sahlins's "Chayanov's Rule" and Chayanov's own analysis. In conclusion I raise the issue of the continuing identification of Chayanov with "Chayanov's Rule" and consider a number of possible reasons for this. 相似文献
994.
Activation of granulocyte cytotoxic function by purified mouse colony-stimulating factors 总被引:15,自引:0,他引:15
A F Lopez N A Nicola A W Burgess D Metcalf F L Battye W A Sewell M Vadas 《Journal of immunology (Baltimore, Md. : 1950)》1983,131(6):2983-2988
Highly purified mouse colony-stimulating factors (CSF) were tested for their effect on neutrophil cytotoxic function in a homologous antibody-dependent cell-mediated cytotoxicity (ADCC) assay in which TNP-coupled mouse thymoma cells coated with mouse anti-TNP antibodies were used as targets, and purified normal mouse bone marrow neutrophils or induced peritoneal neutrophils were used as effector cells. Biochemically pure granulocyte-macrophage (GM)- and granulocyte (G)-CSF enhanced the cytotoxic activity of neutrophils obtained from both sources, allowing them to kill target cells at low antibody concentrations. Furthermore, GM- and G-CSF showed an additive effect, suggesting either the presence of separate receptors for GM- and G-CSF or of separate subsets of neutrophils. Induced peritoneal neutrophils showed a higher level of basal cytotoxic activity than did bone marrow neutrophils, suggesting neutrophil activation in vivo, but both reached similar levels of cytotoxicity upon maximal stimulation with CSF. In addition, CSF was found to be cross-reactive between mouse and human species in their enhancement of neutrophil cytotoxicity. By testing purified mouse CSF on human neutrophils, it could be shown that G-CSF and GM-CSF are functionally distinct molecules, because only G-CSF enhanced ADCC by human neutrophils. These experiments show that the purified factors that control the production of neutrophils by progenitor cells in vitro also activate differentiated neutrophils to carry out their cytotoxic activity in a more effective manner. 相似文献
995.
Marcella Maddaluno Gianluca Grassia Maria Vittoria Di Lauro Antonio Parisi Francesco Maione Carla Cicala Daniele De Filippis Teresa Iuvone Angelo Guglielmotti Pasquale Maffia Nicola Mascolo Armando Ialenti 《PloS one》2012,7(10)
Bindarit, a selective inhibitor of monocyte chemotactic proteins (MCPs) synthesis, reduces neointimal formation in animal models of vascular injury and recently has been shown to inhibit in-stent late loss in a placebo-controlled phase II clinical trial. However, the mechanisms underlying the efficacy of bindarit in controlling neointimal formation/restenosis have not been fully elucidated. Therefore, we investigated the effect of bindarit on human coronary smooth muscle cells activation, drawing attention to the phenotypic modulation process, focusing on contractile proteins expression as well as proliferation and migration. The expression of contractile proteins was evaluated by western blot analysis on cultured human coronary smooth muscle cells stimulated with TNF-α (30 ng/mL) or fetal bovine serum (5%). Bindarit (100–300 µM) reduced the embryonic form of smooth muscle myosin heavy chain while increased smooth muscle α-actin and calponin in both TNF-α- and fetal bovine serum-stimulated cells. These effects were associated with the inhibition of human coronary smooth muscle cell proliferation/migration and both MCP-1 and MCP-3 production. The effect of bindarit on smooth muscle cells phenotypic switching was confirmed in vivo in the rat balloon angioplasty model. Bindarit (200 mg/Kg/day) significantly reduced the expression of the embryonic form of smooth muscle myosin heavy chain, and increased smooth muscle α-actin and calponin in the rat carodid arteries subjected to endothelial denudation. Our results demonstrate that bindarit induces the differentiated state of human coronary smooth muscle cells, suggesting a novel underlying mechanisms by which this drug inhibits neointimal formation. 相似文献
996.
Laura Stocchi Raffaella Cascella Stefania Zampatti Antonella Pirazzoli Giuseppe Novelli Emiliano Giardina 《Current Genomics》2012,13(4):314-320
Many pharmacogenomic biomarkers (PGBM) were identified and translated into clinical practice, affecting the usage of drugs via label updates. In this context, abacavir is one of the most brilliant examples of pharmacogenetic studies translated into clinical practice. Pharmacogenetic studies have revealed that abacavir HSRs are highly associated with the major histocompatibility complex class I. Large studies established the effectiveness of prospective HLA-B*57:01 screening to prevent HSRs to abacavir. Accordingly to these results the abacavir label has been modified: the European Medicines Agency (EMA) and the FDA recommend/suggested that the administration of abacavir must be preceded by a specific genotyping test. The HLA locus is extremely polymorphic, exhibiting many closely related alleles, making it difficult to discriminate HLA-B*57:01 from other related alleles, and a number of different molecular techniques have been developed recently to detect the presence of HLA-B*57:01. In this review, we provide a summary of the available techniques used by laboratories to genotype HLA-B*57:01, outlining the scientific and pharmacoeconomics pros and cons. 相似文献
997.
998.
999.
C Grillo S M Vallee G Piroli B S McEwen A F De Nicola 《The Journal of steroid biochemistry and molecular biology》1992,42(5):515-520
Type I corticosteroid receptors were determined in cytosol from hippocampus (HIPPO) and amygdala (AMYG), using [3H]aldosterone (ALDO), [3H]dexamethasone (DEX) or the mineralocorticoid antagonist [3H]ZK 91587 as ligands. Incubations with the first two compounds also contained the pure glucocorticoid RU 28362 to block type II receptors. Binding of the three ligands was comparable in cytosol from HIPPO and it was slightly higher for [3H]DEX in AMYG. However, after heat-induced receptor transformation, binding to DNA-cellulose was observed for [3H]ALDO-receptor complex obtained from HIPPO or AMYG, whereas it was negligible for [3H]ZK 91587. Receptors charged with [3H]DEX or [3H]ALDO showed similar retention on DNA-cellulose columns in the case of the AMYG, while binding to the polynucleotide was higher for [3H]ALDO in the HIPPO. Finally, only [3H]ALDO was taken up to a significant extent in purified cell nuclei prepared from slices of HIPPO and AMYG previously incubated with the three ligands. It is concluded that binding of a natural agonist steroid may be a prerequisite for type I receptor transformation and translocation from the cytoplasm into the nuclear fraction. DEX binding to type I receptors resembles a partial agonist with antagonist properties, whereas antagonists such as ZK 91587 are bound and retained in cytoplasm, without further translocation. 相似文献
1000.
Light stimulates the betaxanthin accumulation in Celosia plumosa. The induction is partially reversed by far-red and inhibited by actinomycin D, puromycin, salicylaldoxime and 2,4-dinitrophenol, while 3-(3,4-dichlorophenyl)-1,1-dimethylurea has an inhibitory effect only when photosynthesis is operative. In darkness betaxanthins synthesis is promoted by kinetin. 相似文献