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991.
992.
Luigi Sanità di Toppi Antonella Castagna Emanuele Andreozzi Maria Careri Giovanni Predieri Emanuela Vurro Annamaria Ranieri 《Environmental and Experimental Botany》2009,66(2):220-229
Two bread wheat (Triticum aestivum L.) cultivars (Albimonte, traditional cultivar very important in Italy since long time; and Manital, more recent, evincing better productive performances) were grown for 10 d in presence of 0.7 (control), 70 or 350 μM ZnSO4, to verify whether Zn excess was differently managed at inter-varietal and at inter-organ level. Roots were found to be the main site of Zn accumulation, although a moderate metal translocation to leaves occurred in both cultivars. Despite only slight differences in internal Zn concentrations between cultivars, Albimonte seemed to be more sensitive to Zn excess in terms of growth reduction and H2O2 accumulation, suggesting that the diversities in responses to Zn stress should be ascribed here to inter-varietal metabolic differences. In both cultivars, increased NAD(P)H oxidation rate by pH-dependent peroxidases, and reduced detoxification activity by catalase and peroxidases, were responsible for Zn-induced H2O2 accumulation, while total superoxide dismutase content and activity seemed in general to not change or even depress. Moreover, differences in the content of thiol-peptide compounds (glutathione and phytochelatins) were detected, suggesting indeed the setting up of differential response mechanisms to Zn excess at an inter-varietal and inter-organ level. 相似文献
993.
994.
Agnieszka Matera-Witkiewicz Jolanta ?wi?tek-Koz?owska Alessandro Pratesi Luigi Messori 《Journal of inorganic biochemistry》2009,103(5):678-688
A series of linear tetrapeptides containing two histidyl residues in position 2 and 4, namely DHGH, DHGdH, KHGH, KHGdH, Ac-DHGH-NH2, Ac-DHGdH-NH2, Ac-KHGH-NH2, and Ac-KHGdH-NH2, were synthesized and characterised. Their copper(II) binding properties were investigated in depth through a variety of physicochemical methods. Potentiometric titrations were first carried out to establish the stoichiometry and the stability of the resulting copper(II)-peptide complexes. The copper(II) chromophores that are formed in the various cases in dependence of pH were subsequently characterised by extensive spectroscopic analysis (UV-Vis, EPR, CD) in strict correlation with potentiometric data. The effects of the nature of the first amino acid (Lys versus Asp) and of N-terminal amino group protection on copper(II) binding were specifically addressed. On turn, the careful comparison of the copper(II) coordination abilities of the linear peptides with those of their cyclic analogs provided insight into the effects of cyclization on the overall metal binding properties. 相似文献
995.
SlyD from Escherichia coli is a peptidyl–prolyl cis–trans isomerase involved in [Ni–Fe] hydrogenase metallocentre assembly in bacteria. We present here the backbone and side chain
assignments for E. coli SlyD. 相似文献
996.
Daniela Marone Ana I. Del Olmo Giovanni Laidò Josefina C. Sillero Amero A. Emeran Maria A. Russo Pina Ferragonio Valentina Giovanniello Elisabetta Mazzucotelli Anna M. De Leonardis Pasquale De Vita Antonio Blanco Luigi Cattivelli Diego Rubiales Anna M. Mastrangelo 《Molecular breeding : new strategies in plant improvement》2009,24(1):25-39
The Italian durum wheat cultivar Creso possesses a high level of durable resistance to leaf rust based on both hypersensitive
and non-hypersensitive components. In order to investigate the genetic basis of this resistance, a segregating population
composed of 123 recombinant inbred lines (RILs) derived from the cross Creso × Pedroso, was evaluated for disease severity
in adult plants under field conditions. Furthermore, the resistance of parents and RILs was evaluated by assessing macroscopically
the latency period and microscopically the number and type of pathogen colonies formed following artificial inoculation with
a specific isolate. This experiment was performed at controlled conditions at two developmental stages. Besides some minor
QTLs, one major QTL explaining both reduction of disease severity in the field and increased latency period was found on the
long arm of chromosome 7B, and closely associated PCR-based and DArT markers were identified.
Daniela Marone and Ana I. Del Olmo contributed equally to the work. 相似文献
997.
Nicoletta Bivi Milena Romanello Richard Harrison Ian Clarke David C Hoyle Luigi Moro Fulvia Ortolani Antonella Bonetti Franco Quadrifoglio Gianluca Tell Daniela Delneri 《Genome biology》2009,10(9):R93
Background
Nitrogen-containing bisphosphonates are the elected drugs for the treatment of diseases in which excessive bone resorption occurs, for example, osteoporosis and cancer-induced bone diseases. The only known target of nitrogen-containing bisphosphonates is farnesyl pyrophosphate synthase, which ensures prenylation of prosurvival proteins, such as Ras. However, it is likely that the action of nitrogen-containing bisphosphonates involves additional unknown mechanisms. To identify novel targets of nitrogen-containing bisphosphonates, we used a genome-wide high-throughput screening in which 5,936 Saccharomyces cerevisiae heterozygote barcoded mutants were grown competitively in the presence of sub-lethal doses of three nitrogen-containing bisphosphonates (risedronate, alendronate and ibandronate). Strains carrying deletions in genes encoding potential drug targets show a variation of the intensity of their corresponding barcodes on the hybridization array over the time.Results
With this approach, we identified novel targets of nitrogen-containing bisphosphonates, such as tubulin cofactor B and ASK/DBF4 (Activator of S-phase kinase). The up-regulation of tubulin cofactor B may explain some previously unknown effects of nitrogen-containing bisphosphonates on microtubule dynamics and organization. As nitrogen-containing bisphosphonates induce extensive DNA damage, we also document the role of DBF4 as a key player in nitrogen-containing bisphosphonate-induced cytotoxicity, thus explaining the effects on the cell-cycle.Conclusions
The dataset obtained from the yeast screen was validated in a mammalian system, allowing the discovery of new biological processes involved in the cellular response to nitrogen-containing bisphosphonates and opening up opportunities for development of new anticancer drugs. 相似文献998.
999.
1000.
Semi-viviparous embryo development and dehydrin expression in the mangrove Rhizophora mucronata Lam.
Flora AbdulRahman Ismail Lisette M. C. Nitsch Mieke M. C. Wolters-Arts Celestina Mariani Jan W. M. Derksen 《Sexual plant reproduction》2010,23(2):95-103
Rhizophora mucronata Lam. is a tropical mangrove with semi-viviparous (cotyledon body protrusion before shedding), non-quiescent and non-desiccating
(recalcitrant) seeds. As recalcitrance has been thought to relate to the absence of desiccation-related proteins such as dehydrins,
we for the first time systematically described and classified embryogenesis in R. mucronata and assessed the presence of dehydrin-like proteins. Embryogenesis largely follows the classic pattern till stage eight,
the torpedo stage, with the formation of a cotyledonary body. Ovule and embryo express radical adaptations to semi-vivipary
in the saline environment: (1) A large, highly vacuolated and persistent endosperm without noticeable food reserves that envelopes
the developing embryo. (2) Absence of vascular tissue connections between embryo and maternal tissue, but, instead, transfer
layers in between endosperm and integument and endosperm and embryo. Dehydrin-like proteins (55–65 kDa) were detected by the
Western analysis, in the ovules till stage 10 when the integuments are dehisced. An additional 50 kDa band was detected at
stages 6–8. Together these results suggest a continuous flow of water with nutrients from the integument via the endosperm
to the embryo, circumventing the vascular route and probably suppressing the initially induced dehydrin expression. 相似文献