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101.
Comparison of the Neurovirulence of a Vaccine and a Wild-Type Mumps Virus Strain in the Developing Rat Brain 总被引:3,自引:1,他引:2
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Prior to the adoption of widespread vaccination programs, mumps virus was the leading cause of virus-induced central nervous system (CNS) disease. Mumps virus-associated CNS complications in vaccinees continue to be reported; outside the United States, some of these complications have been attributed to vaccination with insufficiently attenuated neurovirulent vaccine strains. The development of potentially neurovirulent, live, attenuated mumps virus vaccines stems largely from the lack of an animal model that can reliably predict the neurovirulence of mumps virus vaccine candidates in humans. The lack of an effective safety test with which to measure mumps virus neurovirulence has also hindered analysis of the neuropathogenesis of mumps virus infection and the identification of molecular determinants of neurovirulence. In this report we show, for the first time, that mumps virus infection of the neonatal rat leads to developmental abnormalities in the cerebellum due to cerebellar granule cell migration defects. The incidence of the cerebellar abnormalities and other neuropathological and clinical outcomes of mumps virus infection of the neonatal rat brain demonstrated the ability of this model to distinguish neurovirulent (Kilham) from nonneurovirulent (Jeryl Lynn) mumps virus strains. Thus, this neonatal rat model may prove useful in evaluating the neurovirulence potential of new live, attenuated vaccine strains and may also be of value in elucidating the molecular basis of mumps virus neurovirulence. 相似文献
102.
Tetracycline fluorescence as calcium-probe for nerve membrane with some model studies using erythrocyte ghosts 总被引:7,自引:0,他引:7
Summary The tetracycline dyes, particularly chlorotetracycline, have been employed as probes of membrane-associated calcium during the excitation process of nerve. Both squid giant axons, stained internally, and lobster nerves, stained externally, show a small increase in fluorescent light during the action potential. Increasing the calcium concentration bathing a lobster nerve leads to a larger optical signal. Adding fluoride ion to the inside of a squid axon, which might be expected to influence the internal calcium-ion concentration, also leads to a larger optical signal. Squid axons have been studied under conditions of voltage clamp and the hyperpolarizing response. Model studies were done with erythrocyte ghosts to clarify the influence of membranes and calcium on the fluores-cence of the tetracyclines. Chlorotetracycline may be monitoring calcium concentration associated with the inner surface of the nerve membrane. 相似文献
103.
Maria Letizia Ciavatta Stella García‐Matucheski Marianna Carbone Guido Villani Maria Rosaria Nicotera Claudia Muniain Margherita Gavagnin 《化学与生物多样性》2017,14(9)
The lipophilic extracts of two marine aeolid nudibranch molluscs of the genus Spurilla collected in distinct geographical areas have been chemically analyzed. The Et2O extracts of the nudibranchs were dominated by the presence of usual fatty acids and sterols and contained terpenoid compounds 1 – 3 as minor metabolites. Spurillin A ( 1 ) and spurillin B ( 3 ) were new molecules whereas cis‐γ‐monocyclofarnesol ( 2 ) was already reported in the literature as a synthesis product. Interestingly, bursatellin ( 4 ), previously isolated from anaspidean molluscs of the genus Bursatella, was found in the butanol extract of both Spurilla species. Compounds 1 – 4 were not detected in the extracts of the sea‐anemone preys collected together with the molluscs. 相似文献
104.
Background
Expression systems based on self-cleavable intein domains allow the generation of recombinant proteins with a C-terminal thioester. This uniquely reactive C-terminus can be used in native chemical ligation reactions to introduce synthetic groups or to immobilize proteins on surfaces and nanoparticles. Unfortunately, common refolding procedures for recombinant proteins that contain disulfide bonds do not preserve the thioester functionality and therefore novel refolding procedures need to be developed. 相似文献105.
Transplastomic tobacco plants expressing a fatty acid desaturase gene exhibit altered fatty acid profiles and improved cold tolerance 总被引:4,自引:0,他引:4
106.
107.
M. C. Carbone M. Pinto F. Antonelli F. Amicarelli M. Balata M. Belli L. Conti Devirgiliis L. Ioannucci S. Nisi O. Sapora L. Satta Giustina Simone E. Sorrentino M. A. Tabocchini 《Radiation and environmental biophysics》2009,48(2):189-196
Previously we reported that yeast and Chinese hamster V79 cells cultured under reduced levels of background environmental
ionizing radiation show enhanced susceptibility to damage caused by acute doses of genotoxic agents. Reduction of environmental
radiation dose rate was achieved by setting up an underground laboratory at Laboratori Nazionali del Gran Sasso, central Italy.
We now report on the extension of our studies to a human cell line. Human lymphoblastoid TK6 cells were maintained under identical
in vitro culture conditions for six continuous months, at different environmental ionizing radiation levels. Compared to “reference”
environmental radiation conditions, we found that cells cultured in the underground laboratories were more sensitive to acute
exposures to radiation, as measured both at the level of DNA damage and oxidative metabolism. Our results are compatible with
the hypothesis that ultra-low dose rate ionizing radiation, i.e. environmental radiation, may act as a conditioning agent
in the radiation-induced adaptive response. 相似文献
108.
109.
Using ectomycorrhizal root tip morphotyping (anatomical and morphological identification), molecular analysis (internal transcribed
spacer region amplification and sequencing), and fruitbody sampling, we assessed diversity and composition of the ectomycorrhizal
fungal community colonizing juvenile Pinus pinaster Ait. under natural conditions in NW Spain. Overall, we found 15 Basidiomycetes and two Ascomycetes. Members of the family
Thelephoraceae represented up to 59.4% of the samples. The most frequent species was Tomentella sublilacina followed by Thelephora terrestris, Russula drimeia, Suillus bovinus, and Paxillus involutus, while the less frequent were Pseudotomentella tristis, Lactarius subdulcis, Russula ochroleuca, and Entoloma conferendum. From October 2007 to June 2008, we sampled 208 sporocarps belonging to seven genera and nine species: Thelephora terrestris, Paxillus involutus, Suillus bovinus, Xerocomus badius, Scleroderma verrucosum, Amanita gemmata, A. rubescens, Amanita sp., and Russula sp. The species belonging to the genus Amanita, X. badius and S. verrucosum were not found on root samples. By comparing our results with a bibliographic review of papers published from 1922 to 2006,
we found five genera and six species which have not been previously reported in symbiosis with P. pinaster. This is the first time that the diversity of the ectomycorrhizal fungal community associated with P. pinaster was investigated using molecular techniques. Considering that only 38% of the genera found by sequencing were found as fruitbodies,
we conclude that integrating morphotyping and sporocarps surveys with molecular analysis of ectomycorrhizas is important to
documenting the ectomycorrhizal fungus community.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
110.
Paola Barraja Virginia Spanò Diana Patrizia Anna Carbone Girolamo Cirrincione Daniela Vedaldi Alessia Salvador Giampietro Viola Francesco Dall’Acqua 《Bioorganic & medicinal chemistry letters》2009,19(6):1711-1714
A convenient synthesis of the pyrano[2,3-e]isoindol-2-one ring system, an heteroanalogue of angelicin, is reported. Our synthetic approach consists of the annelation of the pyran ring on the isoindole moiety using 5-dialkylamino- or 5-hydroxymethylene intermediates as building blocks. The photoantiproliferative activity of the new derivatives was studied. Some of them bearing the benzyl group at the 8 position were active with IC50 in the micromolar range. Cell cytotoxicity involves apoptosis, alteration of cell cycle profile and membrane photodamage. 相似文献