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281.
282.
Phylogenetic analyses of the isonychiid mayflies (Ephemeroptera: Isonychiidae) in the northeast palearctic region
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We investigated the molecular phylogeny of isonychiid mayflies inhabiting the East Palearctic region, Isonychia (Isonychia) japonica, Isonychia (Isonychia) ignota, Isonychia (Isonychia) ussurica and Isonychia (Prinoides) shima. We discuss their genetic structures, phylogeny and phylogeography. We collected a total of 100 specimens of isonychiid mayfly species from 47 localities of the Northeast Palearctic region (the Japanese archipelago, the Korean peninsula, the Russian Far East and Mongolia). We analyzed the DNA sequences at the mtDNA COI and 16S rRNA regions, and the nuDNA Histone H3 region. As a result of our genetic analyses of the four Northeast Palearctic isonychiid mayflies, their monophyly at the species level was supported by both the mtDNA (COI and 16S rRNA regions) and the nuDNA (Histone H3 region). In addition, it also became clear that significantly large genetic differentiation exists at the inter‐species level; thus, the relationship of “shima + (japonica + (ignota + ussurica))” is supported. Among the four isonychiid mayflies of the Northeast Palearctic area, I. (P.) shima was shown to be a basal‐most linage within the included species 相似文献
283.
Kazuki Matsubara Eiji Yamamoto Nobuya Kobayashi Takuro Ishii Junichi Tanaka Hiroshi Tsunematsu Satoshi Yoshinaga Osamu Matsumura Jun-ichi Yonemaru Ritsuko Mizobuchi Toshio Yamamoto Hiroshi Kato Masahiro Yano 《PloS one》2016,11(3)
Biomass yield of rice (Oryza sativa L.) is an important breeding target, yet it is not easy to improve because the trait is complex and phenotyping is laborious. Using progeny derived from a cross between two high-yielding Japanese cultivars, we evaluated whether quantitative trait locus (QTL)-based selection can improve biomass yield. As a measure of biomass yield, we used plant weight (aboveground parts only), which included grain weight and stem and leaf weight. We measured these and related traits in recombinant inbred lines. Phenotypic values for these traits showed a continuous distribution with transgressive segregation, suggesting that selection can affect plant weight in the progeny. Four significant QTLs were mapped for plant weight, three for grain weight, and five for stem and leaf weight (at α = 0.05); some of them overlapped. Multiple regression analysis showed that about 43% of the phenotypic variance of plant weight was significantly explained (P < 0.0001) by six of the QTLs. From F2 plants derived from the same parental cross as the recombinant inbred lines, we divergently selected lines that carried alleles with positive or negative additive effects at these QTLs, and performed successive selfing. In the resulting F6 lines and parents, plant weight significantly differed among the genotypes (at α = 0.05). These results demonstrate that QTL-based selection is effective in improving rice biomass yield. 相似文献
284.
Coliform group bacteria, Staphylococcus aureus , salmonella and proteus were not detected in four samples of kusaya gravy, a kind of brine used for the production of special salt-dried fish in Japan. Vibrio parahaemolyticus at a level of 101 /ml was presumptively detected only in one sample. When inoculated into the gravy at a level of 107 -108 /ml, none of these bacteria grew. Vibrio parahaemolyticus, Escherichia coli and Proteus morganii rapidly decreased in number and were not detectable after 5 d. Staphylococcus aureus numbers reduced only 1 log cycle after incubation for 7 d in the gravy. These results indicate the safety of the gravy with respect to the organisms. 相似文献
285.
286.
Kazuki Oka Hiroshi Maeda Shoichi Ikeda 《International journal of biological macromolecules》1983,5(6)
The effects of eight divalent metal ions on fully neutralized poly(S-carboxyethyl-l-cysteine) have been studied by means of circular dichroism. Four ionic species (Cd2+, Cu2+, Zn2+ and Ni2+) effectively induce the β-form, while the other four species (Co2+, Ba2+, Ca2+ and Mg2+) are not effective. Specifically, Mg(ClO4)2 is ineffective, even at 1.86 m. The effect of Cu2+ ions on the polypeptide conformation is significant at pH values other than in the neural range. Comparison of the present results with previous ones from the lower side chain homologue, poly(S-carboxymethyl-l-cysteine), shows that Cd2+ and Zn2+ ions are more effetive but Co2+ ions are much less effective in the polypeptide studied here. Random coils of poly(S-carboxyethyl-l-cysteine) are more soluble while the β-form is less soluble compared with the respective conformations of the lower side-chain homologue. 相似文献
287.
Aqueous dialyzate of spinach was separated by Sephadex G-100, G-25 gel-filtrations and DEAE-cellulose ion exchange chromatography, and the effects of the fractions on growth of human-derived normal and cancer cell lines were studied. One of the fractions (SPW2) from a Sephadex G-100 gel-filtration of dialyzate promoted growth of a hybridoma cell line (HB4C5). Sephadex G-25 gel filtration of the SPW2 fraction produced four main fractions; SPW2-1, SPW2-2, SPW2-3 and SPW2-4. Among them, the SPW2-1, SPW2-3 and SPW2-4 fractions promoted the growth of a histiocytic lymphoma cell line (U-937) and hybridoma cell lines (HB4C5 and SI102). Both SPW2-3 and SPW2-4 fractions inhibited the growth of a breast cancer cell line (MCF-7). The SPW2-3 fraction, especially, was found to inhibit growth of cancer cell lines such as MCF-7, a differentiated hepatoma (HuH-7), a lung adenocarcinoma (PC-8), a lung squamous carcinoma (QG-56), and a lung anaplastic carcinoma (QG-90) more preferentially than that of normal cell lines. It was also found that a constituent of the SPW2-3 fraction caused the morphological alteration of U-937 cells in serum-free medium. 相似文献
288.
289.
Zwe-Ling Kong Misao Miwa Hiroki Murakami Kazuki Shinohara 《In vitro cellular & developmental biology. Plant》1990,26(10):949-954
Summary A human macrophagelike cell line which grows in serum-free medium was established from a histiocytic lymphoma cell line, U-937.
U-937 cells failed to differentiate into macrophagelike cells in serum-free medium plus 12-O-tetradecanoyl phorbol 13-acetate (TPA). Fibronectin and albumin in serum were necessary for differentiation of U-937 ceds
into macrophagelike cells in enriched RDF medium supplemented with insulin, transferrin, ethanolamine, selenite, egg yolk
lipoprotein (eRDF-ITESL medium). The established cell line exhibited several characteristic properties of macrophage such
as nitroblue tetrazolium reduction, phagocytic and α-naphthylbutyrate-esterase activities, and tumor necrosis factor and interleukin
1 production. At present the cells have been continuously maintained in eRDF-ITESL medium through over 150 passages. 相似文献
290.
We examined the nestmate discrimination ability of Diacamma sp., an ant that reproduces by colony budding. We also tested for a relationship between internest distance and hostility. Hostility toward non‐nestmates was significantly stronger than that toward nestmates, suggesting that Diacamma sp. discriminates between nestmates and non‐nestmates. There was no significant correlation between internest hostility and internest distance, which indicates the absence of a “dear enemy” phenomenon in this species. 相似文献