全文获取类型
收费全文 | 1952篇 |
免费 | 120篇 |
国内免费 | 2篇 |
出版年
2019年 | 14篇 |
2018年 | 18篇 |
2017年 | 21篇 |
2016年 | 32篇 |
2015年 | 44篇 |
2014年 | 51篇 |
2013年 | 123篇 |
2012年 | 86篇 |
2011年 | 95篇 |
2010年 | 43篇 |
2009年 | 63篇 |
2008年 | 103篇 |
2007年 | 70篇 |
2006年 | 111篇 |
2005年 | 99篇 |
2004年 | 98篇 |
2003年 | 115篇 |
2002年 | 115篇 |
2001年 | 50篇 |
2000年 | 44篇 |
1999年 | 43篇 |
1998年 | 39篇 |
1997年 | 30篇 |
1996年 | 28篇 |
1995年 | 28篇 |
1994年 | 27篇 |
1993年 | 24篇 |
1992年 | 30篇 |
1991年 | 16篇 |
1990年 | 13篇 |
1989年 | 17篇 |
1988年 | 18篇 |
1987年 | 12篇 |
1986年 | 17篇 |
1984年 | 16篇 |
1983年 | 17篇 |
1982年 | 26篇 |
1981年 | 28篇 |
1980年 | 18篇 |
1979年 | 26篇 |
1978年 | 23篇 |
1977年 | 11篇 |
1976年 | 20篇 |
1975年 | 10篇 |
1974年 | 17篇 |
1973年 | 17篇 |
1972年 | 13篇 |
1970年 | 13篇 |
1969年 | 13篇 |
1968年 | 14篇 |
排序方式: 共有2074条查询结果,搜索用时 46 毫秒
81.
Michio Himeno Naoto Koyama Tomohiko Funato Tohru Komano 《Bioscience, biotechnology, and biochemistry》2013,77(5):1461-1468
Cultured insect cells, TN-368 from the cabbage looper, swelled and burst upon treatment with the enzyme-digested delta-endotoxin of Bacillus thuringiensis var. aizawai. The cytotoxic sweelling was depended upon the amount of the delta-endotoxin added and the concentration of NaCl or KC1 in the isotonic solution. The concentration of Na+ in the swollen cells approximately doubled in isotonic NaCl, while that of K+ decreased to 10% of the original cellular concentration. The cell swelling was inhibited by tetrodotoxin and also by ouabain in only KC1 isotonic solution. On the other hand, 4-aminopyridine stimulated the swelling in the isotonic KC1 solution, These results indicate that the delta-endotoxin induces the stimulation of Na+ influx and K+ efflux in the isotonic NaCl solution, and also stimulates the Na+, K+-ATPase in the isotonic KC1 solution. The cytotoxic swelling was also blocked by cAMP, AMP, ATP, GTP, and NAD, but not by adenosine and GMP. These results suggest the participation of nucleotide derivatives in the action of delta-endotoxin. 相似文献
82.
83.
84.
Junichi Ueda Takao Yokota Nobutaka Takahashi Michio Yoshida Jiro Kato 《Bioscience, biotechnology, and biochemistry》2013,77(12):3083-3086
A root growth-promoting factor was isolated from Artemisia capillaris Thunb. The chemical structure of this compound was elucidated as methyl 3-(3-methylbut-2-enoyl)-4-hydroxycinnamate (capillarol) on the basis of its spectroscopic analysis. At 5×10–4m this compound promoted rice root growth to 180% of the control value. 相似文献
85.
86.
Kunitoyo Shibuya Michio Tanaka Takeo Nanbata Kiyoshi Isono Saburo Suzuki 《Bioscience, biotechnology, and biochemistry》2013,77(7):1229-1236
Polyoxins D, E, and F which possess 5-carboxyuracil as the nucleobase were reacted selectively with sodium bisulfite at pH 4.0 resulting in facile decarboxylation to afford corresponding 5,6-dihydrouracil-6-sulfonates and uracil type polyoxins (polyoxins L, M, and K) in good yield. The former compounds were also converted to the latter almost quantitatively with mild alkali treatment. Biological activities of the transformed compounds were described. 相似文献
87.
88.
Satoshi Yamamoto Kenji Minami Keiichi Fukaya Kohji Takahashi Hideki Sawada Hiroaki Murakami Satsuki Tsuji Hiroki Hashizume Shou Kubonaga Tomoya Horiuchi Masamichi Hongo Jo Nishida Yuta Okugawa Ayaka Fujiwara Miho Fukuda Shunsuke Hidaka Keita W. Suzuki Masaki Miya Hitoshi Araki Hiroki Yamanaka Atsushi Maruyama Kazushi Miyashita Reiji Masuda Toshifumi Minamoto Michio Kondoh 《PloS one》2016,11(3)
Recent studies in streams and ponds have demonstrated that the distribution and biomass of aquatic organisms can be estimated by detection and quantification of environmental DNA (eDNA). In more open systems such as seas, it is not evident whether eDNA can represent the distribution and biomass of aquatic organisms because various environmental factors (e.g., water flow) are expected to affect eDNA distribution and concentration. To test the relationships between the distribution of fish and eDNA, we conducted a grid survey in Maizuru Bay, Sea of Japan, and sampled surface and bottom waters while monitoring biomass of the Japanese jack mackerel (Trachurus japonicus) using echo sounder technology. A linear model showed a high R2 value (0.665) without outlier data points, and the association between estimated eDNA concentrations from the surface water samples and echo intensity was significantly positive, suggesting that the estimated spatial variation in eDNA concentration can reflect the local biomass of the jack mackerel. We also found that a best-fit model included echo intensity obtained within 10–150 m from water sampling sites, indicating that the estimated eDNA concentration most likely reflects fish biomass within 150 m in the bay. Although eDNA from a wholesale fish market partially affected eDNA concentration, we conclude that eDNA generally provides a ‘snapshot’ of fish distribution and biomass in a large area. Further studies in which dynamics of eDNA under field conditions (e.g., patterns of release, degradation, and diffusion of eDNA) are taken into account will provide a better estimate of fish distribution and biomass based on eDNA. 相似文献
89.
Keisuke Sugimoto Shuhei Tsuchiya Masahiro Omori Ryo Matsuda Masahito Fujio Kensuke Kuroda Masazumi Okido Hideharu Hibi 《Biochemistry and Biophysics Reports》2016
Osseointegration is the structural and functional connection between bone tissues and implants such as titanium dioxide (TiO2). The bone-TiO2 interface is thought to contain proteoglycans. However, exhaustive analysis of the proteins in this layer has not been performed. In this study, we evaluated the bone protein adhered on the surface of TiO2 comprehensively. Pig bone protein was extracted by sequential elutions with guanidine, 0.1 M EDTA, and again with guanidine. The proteins obtained from these extractions were allowed to adhere to an HPLC column packed with TiO2 and were eluted with 0.2 M NaOH. The eluted proteins were identified by LC/MS/MS and included not only proteoglycans but also other proteins such as extracellular matrix proteins, enzymes, and growth factors. Calcium depositions were observed on TiO2 particles incubated with bone proteins, guanidine-extracted proteins adhered to TiO2 displayed significantly high amounts of calcium depositions. 相似文献
90.