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481.
Nazuki Kasuya Hideyuki Mitsui Tadashi Aotsuka Masahito T. Kimura 《Entomological Science》2013,16(2):227-234
The diversity and host associations of parasitoids attacking mycophagous drosophilids were studied in Tokyo (a warm‐temperate region) and Sapporo (a cool‐temperate region) in Japan. Field collections were carried out using traps baited with mushrooms in May, June, September and October 2009 in Tokyo and in July and August 2010 in Sapporo. The major drosophilid species that emerged from mushroom baits was Drosophila bizonata in Tokyo and D. orientacea in Sapporo. In total, 13 parasitoid species emerged from drosophilids occurring in mushroom baits, and 11 of them were larval parasitoids belonging to Braconidae and Figitidae. Among the 11 larval parasitoids, 10 were collected in Tokyo, while only two were collected in Sapporo. It is not known why their diversity differed so much between these two regions. Four of the 11 larval parasitoids have also been recorded from drosophilid larvae occurring in fruit (banana). The use of these two habitats (mushrooms and fruit) by these four species seems to reflect the occurrence (i.e. resource use) of their suitable hosts. On the other hand, most larval parasitoids from Tokyo attacked D. bizonata, and two larval parasitoids from Sapporo attacked D. orientacea, suggesting that the abundance of potential hosts is one of the important factors affecting their host use. 相似文献
482.
Masaaki Sawa Hirotaka Tateishi Kazuhiro Mizuno Hiroshi Harada Mayumi Oue Hiroshi Tsujiuchi Yasuji Furutani Shiro Kato 《Bioorganic & medicinal chemistry letters》2004,14(24):1121
A series of tryptamine derivatives with modified sulfonamide were designed, synthesized, and evaluated for their ability to stimulate cAMP accumulation in CHO cells expressing the cloned human β3-adrenergic receptor (AR). For this series of compounds, our objective was to symmetrize the α-position of the tryptamine moiety maintaining its activity and reducing the cost of production. Compound 11h, having m-aminobenzene, exhibited excellent agonistic activity for β3-AR with excellent subtype selectivity. 相似文献
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487.
Yoshinobu Kaneko Akio Toh-e Isao Banno Yasuji Oshima 《Molecular & general genetics : MGG》1989,220(1):133-139
Summary The structural gene, PHO13, for the specific p-nitrophenyl phosphatase of Saccharomyces cerevisiae was cloned and its nucleotide sequence determined. The deduced PHO13 protein consists of 312 amino acids and its molecular weight is 34635. The disruption of the PHO13 gene produced no effect on cell growth, sporulation, or viability of ascospores. The PHO13 locus was mapped at 1.9 centimorgans from the HO locus on the left arm of chromosome IV. By chromosome fragmentation, the PHO13 locus was found to be located about 72 kb from the left-hand telomere of chromosome IV and distal to the HO locus. 相似文献
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Yoshifumi Jigami Toshio Omori Yasuji Minoda 《Bioscience, biotechnology, and biochemistry》2013,77(9):1781-1788
To clarify biodegradation pathways of isoalkyl substituted aromatic hydrocarbons, oxidation products of isopropylbenzene and isobutylbenzene by Ps. desmolytica S449B1 and Ps. convexa S107B1 were examined.Oxidation products from isopropylbenzene were determined to be 3-isopropylcatechol and (+)-2-hydroxy-7-methyI-6-oxooctanoic acid. Isobutylbenzene was also oxidized to 3-isobutylcatechol and (+)-2-hydroxy-8-methyl-6-oxononanoic acid by the same strains.From these results, the existence of an unknown reductive step in the degradation of these isoalkyl substituted aromatic hydrocarbons and the initial oxidation of these aromatic hydrocarbons by the strains were made clear. The degradation pathways of isopropylbenzene and isobutylbenzene by these strains were discussed. 相似文献
490.
Kazuo Ishii Takashi Furuta Yasuji Kasuya 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1997,704(1-2)
An HPLC method for determining a flavonoid naringin and its metabolite, naringenin, in human urine is presented for application to the pharmacokinetic study of naringin. Isocratic reversed-phase HPLC was employed for the quantitative analysis by using hesperidin for naringin or hesperetin for naringenin as internal standard and solid-phase extraction using a strong anion exchanger, Sep-Pak Accell QMA cartridge. The HPLC assay was carried out using an Inertsil ODS-2 column (250×4.6 mm I.D., 5 μm particle size). The mobile phases were acetonitrile–0.1 M ammonium acetate–acetic acid (18:81:1, v/v; pH 4.7) for naringin and acetonitrile–0.1 M ammonium acetate–triethylamine (25:75:0.05; v/v; pH 8.0) for naringenin. The flow-rate was 1.0 ml min−1. The analyses were performed by monitoring the wavelength of maximum UV absorbance at 282 nm for naringin and at 324 nm for naringenin. The lower limits of quantification were ca. 25 ng/ml for naringin and naringenin with R.S.D. less than 10%. The lower limits of detection (defined as a signal-to-noise ratio of about 3) were approximately 5 ng for naringin and 1 ng for naringenin. A preliminary experiment to investigate the urinary excretion of naringin, naringenin and naringenin glucuronides after oral administration of 500 mg of naringin to a healthy volunteer demonstrated that the present method was suitable for determining naringin and naringenin in human urine. 相似文献