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971.
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974.
Shigeru Iida Beat Mollet Jürg Meyer Werner Arber 《Molecular & general genetics : MGG》1984,198(1):84-89
Summary IS26L and IS26R are the 820 bp long elements found as direct repeats at both ends of the kanamycin resistance transposon Tn2680. They can mediate cointegration in E. coli K12 which contains no IS26 in its chromosome. Cointegration occurs in rec
+ or recA
- strains with similar frequency. Upon cointegration mediated by either IS26R or IS26L, the element is duplicated and integrated into one of many different sites. Both IS26L and IS26R carry 14 bp perfect terminal inverted repeats and generate 8 bp direct repeats at their target sequences. Deletion formation mediated by IS26R was also observed. These functional and structural features of IS26 are characteristic of a prokaryotic mobile genetic element. 相似文献
975.
Kenji Nakajima Akio Sato Terunobu Misono Takeo Iida Kozo Nagayasu 《Bioscience, biotechnology, and biochemistry》2013,77(10):1859-1865
Microorganisms capable of utilizing pristane (2,6,10,14-tetramethylpentadecane) as a sole source of carbon and energy were isolated from soil specimens. A strain BPM 1613, tentatively classified in the genus Nocardia, accumulated several oxidation products of pristane in the culture fluid. Silica gel chromatography of the ethyl ether extract from the culture fluid yielded pristanol and pristanic acid as major products and pristyl pristanate and pristyl aldehyde as minor products. The confirmations on the estimated structures of these oxidation products are described in detail. 相似文献
976.
977.
Toshihiro Yasuda Misuzu Ueki Haruo Takeshita Junko Fujihara Kaori Kimura-Kataoka Reiko Iida Etsuko Tsubota Mikiko Soejima Yoshiro Koda Hideaki Kato Arturo Panduro 《The international journal of biochemistry & cell biology》2010,42(7):1216-1225
A reduction of deoxyribonuclease I (DNase I) activity levels in the serum of patients with autoimmune diseases has been reported. The objectives of this study were to clarify genetic and biochemical aspects of 12 non-synonymous SNPs in the human gene (DNASE1), potentially giving rise to an alteration in the in vivo DNase I activity levels. Genotyping of all the non-synonymous SNPs was performed in healthy subjects of three ethnic groups including 15 populations using newly developed methods. Among them, only four SNPs, R-21S, Y95S, G105R, and Q222R were polymorphic in all or some populations; Asian group showed a relatively low genetic diversity of these SNPs. Furthermore, the distribution pattern of the common SNP Q222R was classified into three ethnic groups. The activity levels of the amino acid-substituted DNase I forms derived from SNPs R-21S, G105R, P132A, and P197S were significantly high compared with that of the wild-type; the polymorphic SNPs R-21S and G105R gave rise to a high activity-harboring DNase I isoform. On the other hand, activity levels from Q35H, R85G, V89M, C209Y, Q222R, and A224P were significantly low, but these SNPs, except Q222R, were not distributed in any of the populations. However, since these SNPs may produce potentially low levels of in vivo DNase I activity, a minor allele in each SNP will be served as a genetic risk factor for autoimmune diseases. These findings on non-synonymous SNPs in DNASE1 may provide a biochemical-genetic basis for the clarification of a possible relationship between DNase I and the diseases. 相似文献
978.
Naoyuki Nishimura Kyoko Kato Akihiro Sumida Kiyomi Ono Hiroyuki Tanouchi Shigeo Iida Daisuke Hoshino Shin-Ichi Yamamoto Toshihiko Hara 《Plant Ecology》2010,206(1):29-40
We examined the effects of different life history strategies and tree competition on species coexistence in a northern coniferous
forest. We investigated the growth and demography of trees with stems ≥1 cm dbh in a 2-ha study plot in the Taisetsu Mountains
of northern Japan. Three species, Abies sachalinensis, Picea
jezoensis, and Picea
glehnii, were found to be dominant in the forest. A. sachalinensis was the most dominant species in the understory, while the two Picea spp. were more abundant in the larger dbh size classes. The turnover rate of A. sachalinensis was about twice that of the Picea spp. The relative growth rate of understory trees in each species did not differ between different canopy conditions (closed
canopy or canopy gap). The competitive advantage between A. sachalinensis and P. glehnii switched as they grew from understory (A. sachalinensis superior competitor) to canopy trees (P. glehnii superior competitor). Meanwhile, A. sachalinensis and P. jezoensis exhibited different environmental preferences. We propose that reversal in competitive superiority between different growth
stages and trade-off between longevity and turnover are more important factors to promote their coexistence than regeneration
niche differentiation related to canopy gaps in this sub-boreal coniferous forest. 相似文献
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980.