全文获取类型
收费全文 | 2348篇 |
免费 | 140篇 |
出版年
2022年 | 23篇 |
2021年 | 29篇 |
2020年 | 17篇 |
2019年 | 22篇 |
2018年 | 37篇 |
2017年 | 31篇 |
2016年 | 66篇 |
2015年 | 73篇 |
2014年 | 77篇 |
2013年 | 170篇 |
2012年 | 139篇 |
2011年 | 133篇 |
2010年 | 84篇 |
2009年 | 69篇 |
2008年 | 134篇 |
2007年 | 118篇 |
2006年 | 141篇 |
2005年 | 133篇 |
2004年 | 123篇 |
2003年 | 140篇 |
2002年 | 131篇 |
2001年 | 38篇 |
2000年 | 38篇 |
1999年 | 41篇 |
1998年 | 29篇 |
1997年 | 31篇 |
1996年 | 27篇 |
1995年 | 22篇 |
1994年 | 20篇 |
1993年 | 17篇 |
1992年 | 24篇 |
1991年 | 17篇 |
1990年 | 20篇 |
1989年 | 15篇 |
1988年 | 20篇 |
1987年 | 12篇 |
1986年 | 12篇 |
1985年 | 24篇 |
1984年 | 16篇 |
1983年 | 9篇 |
1981年 | 17篇 |
1980年 | 12篇 |
1979年 | 10篇 |
1977年 | 10篇 |
1976年 | 9篇 |
1975年 | 11篇 |
1974年 | 10篇 |
1972年 | 13篇 |
1971年 | 11篇 |
1968年 | 11篇 |
排序方式: 共有2488条查询结果,搜索用时 15 毫秒
91.
Koki Horikoshi Yoichi Ohtaka Yonosuke Ikeda 《Bioscience, biotechnology, and biochemistry》2013,77(8):724-727
Ribosomes were isolated from dormant and germinating conidia of Asp. oryzae No. 13. The ribosomes which consisted of 80 S were easily dissociated into 40 S and 60 S in low Mg+ + buffer. Polyribosomes were not found in dormant conidia, but were found in germinating conidia. Ribosomes in Aspergillus fungi consisted of almost equal amount of RNA and protein, and the base compositions of RNA were alike, as compared as ribosomal RNA between dormant and germinating conidia. 相似文献
92.
Michiko Nose Yoichi Nakatani Tei Yamanishi 《Bioscience, biotechnology, and biochemistry》2013,77(2):261-271
By continuing flavor analysis of green tea from a previous paper, further twenty seven compounds were newly identified. These compounds are limonene, α-cubebene, α-copaene, caryophyllene, α-humulene, α- and γ-muurolene, β-sesquiphellandrene, δ-cadinene, calamenene, cubenol, α-cadinol, α-terpineol, n-heptanol, n-nonanol, furfurylalcohol, n-nonanal, N-ethylformylpyrrole, pyrrylmethylketone, 6-methyl-trans-3,5-heptadien-2-one, 2′,2″-dihydro-α-ionone, 6,10,14-trimethyl-2-pentadecanone, cis-3-hexenylcaproate, cis-3-hexenylbenzoate, α-terpinylacetate, coumarin and diphenylamine.Relative quantities of known compounds in intermediate- and high-boiling fraction were determined. 相似文献
93.
94.
Yoichi Ozawa Kenji Mori Masanao Matsui 《Bioscience, biotechnology, and biochemistry》2013,77(7):1383-1386
Thirty eight new compounds with juvenile hormone (JH) activity were synthesized and evaluated biologically on Bombyx mori L. Among them, the activities of 7,8-epoxy-4,8-dimethyl-1 -(p-ethylphenoxy)-3-undecene and 7,8-epoxy-4,8-dimethyl-l-(p-methylphenoxy)-3-undencene were proved to be more than two thousand times as high as that of the C18-Cecropia JH (mixed isomers). Structure-activity relationship of these compounds was discussed. 相似文献
95.
Masanao Matsui Kenji Mori Yoichi Ozawa 《Bioscience, biotechnology, and biochemistry》2013,77(2):193-195
A synthesis of oospolactone (3,4-dimethyl-8-hydroxyisocoumarin), a metabolite of Oospora astringenes, is described. 相似文献
96.
Yoshiaki Iwamuro Michiko Murata Koichiro Kanamaru Yoichi Mikami Takuro Kisaki 《Bioscience, biotechnology, and biochemistry》2013,77(2):525-526
The aroL gene, encoding shikimate kinase of Brevibacterium lactofermentum, a coryneform glutamic acid-producing bacterium, was cloned. Recombinant plasmids containing the aroL gene caused elevated levels of shikimate kinase synthesis in B. lactofermentum. It was found that in addition to the aroL gene, the aroB and aroE genes, encoding dehydroquinate synthase and shikimate dehydrogenase, respectively, also existed on these recombinant plasmids, in complementation tests with various Escherichia coli and B. lactofermentum aromatic amino acid auxotrophs. The aroL, aroB and aroE genes of B. lactofermentum are located closely on the cloned DNA fragment, in that order. It was shown that at least these three aro genes form a cluster on the chromosome of B. lactofermentum. 相似文献
97.
Kazunori Sasaki Tomoyuki Oki Yumi Kai Yoichi Nishiba 《Bioscience, biotechnology, and biochemistry》2013,77(8):1308-1314
The purpose of this study was to investigate the effect of repeated harvesting on the content of caffeic acid (CA) and seven species of caffeoylquinic acids (CQAs) in sweet potato leaves using a newly developed high-performance liquid chromatography method. Six cultivars and two breeding lines were used in this study. Leaves were collected at monthly intervals from 1st harvest (May) to 4th harvest (August) in 2011 and 2012. ANOVA analysis revealed that the contents of CQAs were significantly different among all cultivars and breeding lines, but no significant differences were found for CA. No annual variation was confirmed in CA and CQAs. Repeated harvest of sweet potato leaves affected the content of only 4-CQA and 5-CQA. Post-hoc comparisons using Tukey’s method indicated that the contents of 4-CQA and 5-CQA in sweet potato leaves harvested at first time were significantly higher compared to those at the other harvest times. 相似文献
98.
Yoichi Ozawa Kenji Mori Masanao Matsui 《Bioscience, biotechnology, and biochemistry》2013,77(10):2373-2378
Sixteen new Cecropia juvenile hormone (JH) analogs with different alkyl substituents at C–7 and C–11 were synthesized as stereoisomeric mixtures. The epoxides with n-propyl or n-butyl and methyl groups at C-11 and methyl or ethyl group at C-7 showed high JH activity on Bombyx mori L. Structure-activity relationship of the JH analogs was discussed. 相似文献
99.
Akihiro Okitani Yuzuru Otsuka Mamoru Sugitani Masao Fujimaki 《Bioscience, biotechnology, and biochemistry》2013,77(3):573-579
The properties of the neutral proteolytic activity concentrated in a fraction (F–1) separated from rabbit muscle homogenate were examined by measuring the effects of various reagents and metal ions, the time course of the proteolysis and Ca-stability. The obtained results have indicated that F–1 contains two types of neutral protease active on proteins, tentatively named Protease I and II, The former, which is activated by Ca2+ and Ca-labile, shows an explosive production of Cu-Folin phenol reagent positive materials at the early stage of incubation. The latter, which is Ca-stable, shows a large production of ninhydrin positive materials throughout the incubation time. The proteolysis by F–1 was similar to the autolysis of muscle homogenate in all the properties examined. Therefore, Proteases I and II were assumed to be main enzymes responsible for the muscle proteolysis at the neutral pH region. As there has been no factor denying their functioning in living muscle, it is probable that Proteases I and II take important parts in the muscle catabolism. 相似文献
100.