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911.
A histochemical procedure has been developed for staining aminoacylase-1 (ACY-1) isozymes after electrophoresis on cellulose acetate membranes. N-Formyl-L-methionine and N-acetyl-L-methionine were excellent enzyme substrates in the staining reaction. The ACY-1 isozymes from tissue culture cells of several vertebrate species showed distinguishable electrophoretic patterns. The ACY-1 isozymes in extracts of mouse, human, owl monkey, and African green monkey kidney cells each had electrophoretic mobilities different from those of peptidases S, A, and C from the same cells. Except for African green monkey kidney (CV-1) cells, the animal species expressed a single anodally migrating ACY-1 band. Human-mouse somatic cell hybrids containing the short arm of human chromosome 3 expressed three ACY-1 bands, as would be predicted from the dimeric structure of the enzyme. CV-1 cells expressed two (or three) ACY-1 bands, suggesting the possibility that CV-1 cells contained two alleles at a single locus or two genetic loci for ACY-1.This research was aided by USPHS Grants CA-06656-17 and 1-K6KAI-2352-17 from the National Cancer Institute and the National Institute of Allergy and Infectious Diseases, and by Contract NO1-CP-71058 from the National Cancer Institute. 相似文献
912.
Twelve novel fenfuram-diarylether hybrids were designed, synthesized and characterized by 1H NMR and MS. Their in vitro antifungal activities were evaluated against five phytopathogenic fungi by mycelial growth inhibition method. Most compounds showed significant antifungal effect on Rhizoctonia solani and Sclerotinia sclerotiorum. Compound 1c exhibited the most potent antifungal effect on R. solani with an EC50 value of 0.242 mg/L, superior to the commercial fungicide boscalid (EC50 = 1.758 mg/L) and the lead fungicide fenfuram (EC50 = 7.691 mg/L). Molecular docking revealed that compound 1c featured a higher affinity for succinate dehydrogenase (SDH) than fenfuram. Furthermore, it was shown that the 2-chlorophenyl group of compound 1c formed a π-π stacking with D/Tyr-128 and a Cl-π interaction with B/His-249, which made compound 1c more active than fenfuram against SDH. 相似文献
913.
Two series of piperazine-linked bis(chromene) hybrids that are attached to pyrazole units were synthesized in the current study. Both series are attached to an acyl unit at pyrazole-C3, with one series attached to an acetyl unit and the other to an ethoxycarbonyl unit. A [3+2] cycloaddition protocol was conducted to produce the target hybrids with good yields by reacting the appropriate hydrazonoyl chlorides with chromene-based bis(enaminone) in dioxane containing triethylamine at reflux for 4 h. New hybrids were tested for acetylcholinesterase inhibitory activity at concentrations of 15 and 25 μM, as well as their ability to quench 2,2-diphenylpicrylhydrazyl (DPPH) free radicals at a concentration of 25 μg/mL. In general, the inhibitory activity is related to the electronic properties of the para-substituent that is attached to the arene unit at pyrazole-N1. Furthermore, the acyl unit attached to pyrazole-C3 has a significant effect on the new hybrids′ inhibitory activity. At the previous concentrations, the (3-acetylpyrazole)-linked hybrid attached to p-NO2 units demonstrated the best acetylcholinesterase inhibitory activity, with inhibition percentages of 79.7 and 90.2. Furthermore, the previous hybrid demonstrated the most effective DPPH inhibitory activity, with an inhibition percentage of 87.5. 相似文献
914.
Lech Karpiński Patrick Gorring Jacek Hilszczański Wojciech T. Szczepański Radosław Plewa Krzysztof Łoś Anthony I. Cognato 《Zoologica scripta》2023,52(1):70-85
Hybridisation can lead to the formation of new evolutionary lineages and some described insect species may in fact be first-generation hybrids of their parental species. Anoplistes forticornis and A. galusoi are two closely related cerambycid taxa endemic to Central Asia that exhibit a peculiar geographical distribution. Although the common diagnostic elytral pattern makes these beetles superficially easily distinguishable, there are marked resemblances in their morphology. By applying an integrative taxonomy approach, we verify the taxonomic status of A. forticornis and A. galusoi and test the possibility of hybridisation. The results of our comprehensive morphological examination and molecular analyses targeting mitochondrial (COI, 16S rRNA) and nuclear (arginine kinase, CAD, 28S rRNA) genes support the specific status of these taxa. In mtDNA, the putative hybrid specimen is more closely related to A. forticornis, which indicates that a female of this species bred with a male of A. galusoi. The supposed ecotypic variability (manifested in elytral pattern) is apparently not related to the topography or spatial structure of habitat. The phylogenetic hypothesis supports a peripatric scenario in which populations of the common ancestor had been separated for a significant period of time, first by the mountain ranges of Dzungarian Alatau (~11–10 Ma) and ultimately by the Ili River. The diverged taxa came into recent secondary contact following these isolation events. The methodology presented herein can be widely applied to identify first-generation hybridisation in Coleoptera. 相似文献
915.
M. SANDRA F.L.S. THOMAS 《Botanical journal of the Linnean Society. Linnean Society of London》1983,87(1):55-75
A taxonomic clarification of Petrorhagia section Kohlrauschia (Caryophyllaceae). The morphology of the inflorescence bracts and seeds in Petrorhagia glumacea and the large-flowered form of P. 'prolifera' is reported together with observations on some artificially produced hybrids. Petorhagia glumacea and large-flowered p. 'prolifera' can be distinguished on the basis of bract and seed morphology. The taxonomic status of large-flowered P. 'prolifera' is recognized as P. obcordata. Two groups of intermediate, natural populations are described from the Peloponnese and it is suggested that they are of hybrid origin. The seeds of P. obcordata are polytypic and show a geographical distribution pattern. Seed morphology, which is the most useful diagnostic character for identification, is described in P. prolifera, P. velutina and the tetraploid P. nanteuilii. 相似文献
916.
V. E. Shimko I. V. Kulminskaya L. N. Kalitukho I. A. Gordei 《Russian Journal of Plant Physiology》2009,56(1):126-132
Diversity of photosynthetic characteristics determined by plant genotypes provides the grounds for the increase in potential crop productivity by means of producing plant forms whose photosynthetic apparatus (PSA) has optimal size and functional efficiency. Parental forms of winter rye (Secale cereale L.) and their interline and intravarietal reciprocal F2 hybrids were compared in terms of photosynthetic pigment (PSP) content, characteristics of chlorophyll a (Chl) fluorescence, some morphological traits, and grain productivity. At the booting and anthesis stages, significant divergence in chlorophyllous pigment content and Chl a fluorescence parameters was observed for winter rye inbred lines, rye varieties, and hybrids. The hybrids were revealed whose elevated grain productivity correlated with high PSP content and the highest photosystem II (PSII) activity. Analysis of correlations in reciprocal F2 hybrids at booting and anthesis stages of rye development showed that accumulation of PSII is related to stem-forming capacity and to the flag leaf surface area. In reciprocal hybrids, the correlations between morphological traits, grain productivity, plastid pigments, and photochemical activity were subject to variations. The relationships between PSA parameters and grain productivity in winter rye F2 hybrids varied depending on the developmental stage as well as on crossing combination; this relation was largely determined by the choice of pairs for hybridization, by direction of crosses, and by genetic features of parental forms. 相似文献
917.
Genetic variation in resistance to Fusarium oxysporum f.sp. lilii in the genus Lilium 总被引:4,自引:0,他引:4
Genetic variation in Fusarium resistance in 82 Lilium genotypes was studied. A high level of resistance was found in the Asiatic hybrids (section Sinomartagon) and to a lesser extent in cultivars of L. longiflorum (section Leucolirion). The Oriental hybrids (section Archelirion) showed only moderate resistance. In the sections Sinomartagon, Leucolirion and Martagon species were detected with high levels of resistance. An accession of L. dauricum (section Sinomartagon) was the most resistant source. Possibilities for introgression of Fusarium resistance into cultivars by interspecific hybridisation, using the resistance found in Lilium genotypes, are discussed. 相似文献
918.
DAVID McCLINTOCK F.L.S. 《Botanical journal of the Linnean Society. Linnean Society of London》1989,101(3):279-289
McCLINTOCK, D., 1989. The heathers of Europe and adjacent areas. Andromeda polifolia, Bruckenthalia spiculifolia, Calluna vulgaris , two species of Daboecia , 19 of Erica with five subspecies and seven natural hybrids are discussed. Comment is chiefly given on E. andevalensis, E. maderensis and the group currently denominated: E. anthura, E. manipuliflora, E. multiflora and E. vagans. Two new combinations are made. 相似文献
919.
M. A. Sigareva E. D. Earle 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(1):164-170
Camelina sativa, a wild relative of Brassica crops, is virtually immune to blackspot disease caused by Alternaria brassicicola. Intertribal somatic hybrids were produced between C. sativa and rapid-cycling Brassica oleracea as a step toward the transfer of resistance to this disease into Brassica vegetable crops. The plants recovered were confirmed as somatic hybrids by flow cytometry and RAPD analysis. All hybrids
showed a morphology intermediate between the two parents. Rooted plants grew in soil up to 4–5 weeks, and some produced sterile
flowers. Two of three hybrids tested showed a high level of resistance to A. brassicicola. Resistance was correlated with the induction of high levels of the phytoalexin camalexin 48 h after inoculation, as in the
resistant Camelina fusion partner. In contrast, susceptible somatic hybrids produced much lower levels of camalexin.
Received: 2 April 1998 / Accepted: 14 July 1998 相似文献
920.
Two new bibenzyl-phenylpropane hybrids, dendrophenols A and B ( 1 and 2 ), along with nine known bibenzyls, were isolated from the aerial part of Dendrobium devonianum Paxt. Their structures were determined by extensive spectroscopic methods and methylation. Bioassays revealed that compounds 1–9 were specifically immunosuppressive to T lymphocytes with IC50 values ranging from 0.41 to 9.4 μM, of which compounds 1 (IC50=1.62 μM) and 2 (IC50=0.41 μM) were promising immunosuppressive agents for T lymphocytes with the selectivity indices of 19.9 and 79.5, respectively. 相似文献