全文获取类型
收费全文 | 5518篇 |
免费 | 373篇 |
国内免费 | 3篇 |
出版年
2021年 | 53篇 |
2020年 | 27篇 |
2019年 | 54篇 |
2018年 | 79篇 |
2017年 | 47篇 |
2016年 | 91篇 |
2015年 | 150篇 |
2014年 | 189篇 |
2013年 | 350篇 |
2012年 | 267篇 |
2011年 | 342篇 |
2010年 | 200篇 |
2009年 | 188篇 |
2008年 | 328篇 |
2007年 | 305篇 |
2006年 | 291篇 |
2005年 | 276篇 |
2004年 | 313篇 |
2003年 | 285篇 |
2002年 | 280篇 |
2001年 | 158篇 |
2000年 | 171篇 |
1999年 | 155篇 |
1998年 | 69篇 |
1997年 | 66篇 |
1996年 | 47篇 |
1995年 | 38篇 |
1994年 | 50篇 |
1993年 | 54篇 |
1992年 | 97篇 |
1991年 | 86篇 |
1990年 | 81篇 |
1989年 | 86篇 |
1988年 | 86篇 |
1987年 | 58篇 |
1986年 | 51篇 |
1985年 | 51篇 |
1984年 | 43篇 |
1983年 | 37篇 |
1982年 | 25篇 |
1981年 | 34篇 |
1980年 | 24篇 |
1979年 | 27篇 |
1978年 | 25篇 |
1977年 | 20篇 |
1976年 | 30篇 |
1975年 | 17篇 |
1974年 | 11篇 |
1973年 | 16篇 |
1971年 | 12篇 |
排序方式: 共有5894条查询结果,搜索用时 46 毫秒
1.
Kenji Tsuji Shinji KitamuraHirofumi Makino 《Biochemical and biophysical research communications》2014
The kidneys are exposed to hypoxic conditions during development. Hypoxia-inducible factor (HIF), an important mediator of the response to hypoxia, is believed to have an important role in development. However, the relationship between HIF and branching morphogenesis has not been elucidated clearly. 相似文献
2.
3.
Julie M. Koeman Ryan C. Russell Min-Han Tan David Petillo Michael Westphal Katherine Koelzer Julie L. Metcalf Zhongfa Zhang Daisuke Matsuda Karl J. Dykema Heather L. Houseman Eric J. Kort Laura L. Furge Richard J. Kahnoski Stphane Richard Annick Vieillefond Pamela J. Swiatek Bin Tean Teh Michael Ohh Kyle A. Furge 《PLoS genetics》2008,4(9)
4.
Takahiro Ishii Tatsufumi Okino Yosuke Mino Hiroaki Tamiya Fuyuhiko Matsuda 《Plant Growth Regulation》2007,52(2):131-139
Starfish waste has been shown to be an effective compost material not only in the promotion of plant growth but also in terms
of having insecticidal activity. In the present study, plant growth regulation by chemicals from starfish was examined. The
aqueous fraction from a hot water extract of the starfish Asterias amurensis Lütken showed plant-growth activity, while the aqueous fraction from a methanol extract inhibited growth of Brassica campestris. The lipophilic fraction from the methanol extract also exhibited a plant growth-promoting effect. The active components
from each extract were identified. Asterubine from the hot water extract promoted plant growth. A ceramide from the lipophilic
fraction showed root growth promoting effect, and three glucocerebrosides had promotive effects on the entire plant. Asterosaponins
were identified as the main growth inhibitors in the aqueous fraction of the methanol extract. These active compounds from
starfish waste could be analyzed as potential plant growth regulators in agricultural applications in the future. 相似文献
5.
6.
7.
Masaru Manabe Tetsuhisa Goto Shinji Matsuura 《Bioscience, biotechnology, and biochemistry》2013,77(11):2003-2007
Aflatoxins Bl, B2, G1 and G2 were quantitatively detected by high-performance liquid chromatography on a 12 µl flow-cell in the fluorometric detector using the mobile phase of toluene system instead of chloroform, dichloromethane or methanol system. Various kinds of columns and mobile phases were tested, and fine mutual separation of all the four aflatoxins without quenching their fluorescence was achieved by using sHica gel column and toluene- ethyl acetate-formic acid-methanol (89.0: 7.5: 2.0: 1.5 v/v/v/v). The relationship between the fluorescence peak area and the amount injected was linear in the range of 0.3 ng to 120 ng. This method, as applied to food and feed extracts, is sensitive at the 10~20 ppb levels of the four kinds of aflatoxins. 相似文献
8.
Predicting phenotypes using genome-wide genetic variation and gene expression data is useful in several fields, such as human biology and medicine, as well as in crop and livestock breeding. However, for phenotype prediction using gene expression data for mammals, studies remain scarce, as the available data on gene expression profiling are currently limited. By integrating a few sources of relevant data that are available in mice, this study investigated the accuracy of phenotype prediction for several physiological traits. Gene expression data from two tissues as well as single nucleotide polymorphisms (SNPs) were used. For the studied traits, the variance of the effects of the expression levels was more likely to differ among the genes than were the effects of SNPs. For the glucose concentration, the total cholesterol amount, and the total tidal volume, the accuracy by cross validation tended to be higher when the gene expression data rather than the SNP genotype data were used, and a statistically significant increase in the accuracy was obtained when the gene expression data from the liver were used alone or jointly with the SNP genotype data. For these traits, there were no additional gains in accuracy from using the gene expression data of both the liver and lung compared to that of individual use. The accuracy of prediction using genes that were selected differently was examined; the use of genes with a higher tissue specificity tended to result in an accuracy that was similar to or greater than that associated with the use of all of the available genes for traits such as the glucose concentration and total cholesterol amount. Although relatively few animals were evaluated, the current results suggest that gene expression levels could be used as explanatory variables. However, further studies are essential to confirm our findings using additional animal samples. 相似文献
9.
10.
Genji Matsuda Tetsuo Maita Takayuki Miyanishi Masaki Hayashida 《Journal of Protein Chemistry》1987,6(1):33-46
We have studied the primary structures of myosins from chicken muscles in order to clarify the relationship between structure and function of muscle myosin. The primary structures of the various kinds of light chains from chicken muscle myosins have been determined. We also report the primary structure of the 23K fragment of subfragment-1 (S-1) component from the heavy chain of chicken fast skeletal muscle myosin. In addition, antibody was prepared against the 23K fragment. The antibody was found to inhibit the Mg2+-ATPase activity and the initial Pi burst of the ATPase in the S-1 component. The antibody suppressed the ATP-induced fluorescence enhancement of S-1, though it did not suppress the binding of ATP to S-1. These results are also discussed.This article was presented during the proceedings of the International Conference on Macromolecular Structure and Function, held at the National Defence Medical College, Tokorozawa, Japan, December 1985. 相似文献