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101.
Zooplankton in the Ligurian Sea: Part II. Exploration of their physical and biological forcing functions during summer 2000 总被引:2,自引:0,他引:2
Warren Joseph D.; Demer David A.; McGehee Duncan E.; Di Mento Rossella; Borsani J. Fabrizio 《Journal of plankton research》2004,26(12):1419-1427
A survey of the biological and physical oceanography of theLigurian Sea was conducted in the late summer of 2000. Forty-onestations were sampled for nutrients, oxygen, fluorescence andhydrographic information. Acoustic backscatter measurementswere used to estimate abundance of small (<5 mm) zooplanktonbiovolume versus depth and the distribution of northern krill,Meganyctiphanes norvegica. Net-tow and underwater video datawere collected to identify the zooplankton present. These datawere used to analyze the Ligurian Sea ecosystem for physicaland biological linkages that control zooplankton abundance anddistribution. Results are compared with those from a similarstudy conducted in 1999. Hydrographic sampling showed a domeof dense water in the southwestern middle of the basin. Thehighest chlorophyll a (Chl a) concentrations were measured inthis area, while small zooplankton biovolume was evenly distributedthroughout the survey. Integrated values of Chl a and smallzooplankton biovolume in 2000 were greater than in 1999. Meganyctiphanesnorvegica, siphonophores and salps were the dominant componentsof the macrozooplankton population in the upper 200 m. In thesampled depth strata, siphonophore abundance did not changeduring the day, while M. norvegica were only caught at night.Acoustic backscatter data show that higher densities of M. norvegicaoccurred in deeper water and in the western and southwesternareas of the Ligurian Sea. 相似文献
102.
Daniele Bianchi Rossella Bortolo Antonella Bernardi Ileana Gagliardi Anna Giulia Mercedes Ingrassia 《Biotechnology letters》1995,17(7):711-716
Summary A practical procedure has been developed for the chemoselective microbial hydrolysis of aromatic dicarboxylic esters to give the corresponding monoesters, using cellular lysate and whole cell of Brevibacterium imperiale B222. The produced monoesters can be transformed into hydroxyacids, useful intermediates in the synthesis of polyesters. 相似文献
103.
104.
Background
Many reports have described that there are fewer differences in AD brain neuropathologic lesions between AD patients and control subjects aged 80 years and older, as compared with the considerable differences between younger persons with AD and controls. In fact some investigators have suggested that since neurofibrillary tangles (NFT) can be identified in the brains of non-demented elderly subjects they should be considered as a consequence of the aging process. At present, there are no universally accepted neuropathological criteria which can mathematically differentiate AD from healthy brain in the oldest old. 相似文献105.
Abstract. A model-independent and elementary method of analysis of platelet survival is proposed. The method is based on the finding that the mean and standard deviation of the platelet lifespan can be expressed in the terms of the slope at time 0 and the area under the empirical platelet survival curve. The method is tested using Monte-Carlo simulations and then applied to a set of clinical data. 相似文献
106.
107.
Involvement of sperm acetylated histones and the nuclear isoform of Glutathione peroxidase 4 in fertilization 下载免费PDF全文
108.
Oxylipins from both pathogen and host antagonize jasmonic acid‐mediated defence via the 9‐lipoxygenase pathway in Fusarium verticillioides infection of maize 下载免费PDF全文
Paola Battilani Alessandra Lanubile Valeria Scala Massimo Reverberi Rossella Gregori Claudia Falavigna Chiara Dall'asta Yong‐Soon Park John Bennett Eli J. Borrego Michael V. Kolomiets 《Molecular Plant Pathology》2018,19(9):2162-2176
Oxylipins are a newly emerging group of signals that serve defence roles or promote virulence. To identify specific host and fungal genes and oxylipins governing the interactions between maize and Fusarium verticillioides, maize wild‐type and lipoxygenase3 (lox3) mutant were inoculated with either F. verticillioides wild‐type or linoleate‐diol‐synthase 1‐deleted mutant (ΔFvlds1D). The results showed that lox3 mutants were more resistant to F. verticillioides. The reduced colonization on lox3 was associated with reduced fumonisin production and with a stronger and earlier induction of ZmLOX4, ZmLOX5 and ZmLOX12. In addition to the reported defence function of ZmLOX12, we showed that lox4 and lox5 mutants were more susceptible to F. verticillioides and possessed decreased jasmonate levels during infection, suggesting that these genes are essential for jasmonic acid (JA)‐mediated defence. Oxylipin profiling revealed a dramatic reduction in fungal linoleate diol synthase 1 (LDS1)‐derived oxylipins, especially 8‐HpODE (8‐hydroperoxyoctadecenoic acid), in infected lox3 kernels, indicating the importance of this molecule in virulence. Collectively, we make the following conclusions: (1) LOX3 is a major susceptibility factor induced by fungal LDS1‐derived oxylipins to suppress JA‐stimulating 9‐LOXs; (2) LOX3‐mediated signalling promotes the biosynthesis of virulence‐promoting oxylipins in the fungus; and (3) both fungal LDS1‐ and host LOX3‐produced oxylipins are essential for the normal infection and colonization processes of maize seed by F. verticillioides. 相似文献
109.
M. Fatima Grossi de Sa T. Erik Mirkov Masao Ishimoto Gabriella Colucci Kaye S. Bateman Maarten J. Chrispeels 《Planta》1997,203(3):295-303
Cultivated varieties of the common bean (Phaseolus vulgaris L.) contain an α-amylase inhibitor (αAI-1) that inhibits porcine pancreatic α-amylase (PPA; EC 3.2.1.1) and the amylases
of certain seed weevils, but not that of the Mexican bean weevil, Zabrotes subfasciatus. A variant of αAI-1, called αAI-2, is found in certain arcelin-containing wild accessions of the common bean. The variant
αAI-2 inhibits Z. subfasciatus α-amylase (ZSA), but not PPA. We purified αAI-2 and studied its interaction with ZSA. The formation of the αAI-2-ZSA complex
is time-dependent and occurs maximally at pH 5.0 or below. When a previously isolated cDNA assumed to encode αAI-2 was expressed
in transgenic tobacco seeds, the seeds contained inhibitory activity toward ZSA but not toward PPA, confirming that the cDNA
encodes αAI-2. The inhibitors αAI-1 and αAI-2 share 78% sequence identity at the amino acid level and they differ in an important
region that is part of the site where the enzyme binds the inhibitor. The swap of a tripeptide in this region was not sufficient
to change the specificity of the two inhibitors towards their respective enzymes. The three-dimensional structure of the αAI-1/PPA
complex has just been solved and we recently obtained the derived amino acid sequence of ZSA. This additional information
allows us to discuss the results described here in the framework of the amino acid residues of both proteins involved in the
formation of the enzyme-inhibitor complex and to pinpoint the amino acids responsible for the specificity of the interaction.
Received: 14 April 1997 / Accepted: 10 May 1997 相似文献
110.
G. F. Grossi M. Durante G. Gialanella M. Pugliese I. Mosse 《Radiation and environmental biophysics》1998,37(1):63-67
The search for effective radioprotectors is of major concern in the medical, military, environmental, and space sciences.
Conventional radioprotectors are generally effective only during a single irradiation and display their radioprotective properties
only at high, toxic concentrations. In addition, they reduce somatic radiation effects but are poorly efficient in protecting
from hereditary stochastic radiation effects. In this respect, the pigment melanin merits attention. Experiments referring
to potential melanin effects on the ionising radiation response have been carried out with different biological systems, both
in vivo and in vitro. In this paper, we present results on the response to high- and low-linear energy transfer (LET) radiation
of a human mammary epithelial cell line, H184B5 F5-1 M/10, supplemented by melanin. The incorporation of auto-oxidative (l-dopa) melanin was linear for concentrations from 3 to 10 μg/ml in the growth medium. Concentrations of up to 250 μg/ml did
not significantly impair the cells proliferative ability. No significant protective effect of melanin on the survival of cultured
cells after exposure to alpha-particles (130 keV/μm) or x-rays was observed.
Received: 24 March 1997 / Accepted in revised form: 14 November 1997 相似文献