全文获取类型
收费全文 | 756篇 |
免费 | 16篇 |
国内免费 | 7篇 |
专业分类
化学 | 603篇 |
晶体学 | 15篇 |
力学 | 13篇 |
数学 | 12篇 |
物理学 | 136篇 |
出版年
2023年 | 4篇 |
2022年 | 8篇 |
2021年 | 6篇 |
2020年 | 9篇 |
2019年 | 9篇 |
2018年 | 5篇 |
2017年 | 4篇 |
2016年 | 6篇 |
2015年 | 7篇 |
2014年 | 17篇 |
2013年 | 31篇 |
2012年 | 38篇 |
2011年 | 34篇 |
2010年 | 26篇 |
2009年 | 22篇 |
2008年 | 42篇 |
2007年 | 45篇 |
2006年 | 37篇 |
2005年 | 59篇 |
2004年 | 40篇 |
2003年 | 31篇 |
2002年 | 46篇 |
2001年 | 20篇 |
2000年 | 24篇 |
1999年 | 26篇 |
1998年 | 3篇 |
1997年 | 8篇 |
1996年 | 6篇 |
1995年 | 3篇 |
1994年 | 6篇 |
1993年 | 10篇 |
1992年 | 6篇 |
1991年 | 16篇 |
1990年 | 11篇 |
1989年 | 6篇 |
1988年 | 7篇 |
1987年 | 8篇 |
1986年 | 12篇 |
1985年 | 7篇 |
1984年 | 14篇 |
1983年 | 10篇 |
1981年 | 7篇 |
1980年 | 10篇 |
1979年 | 2篇 |
1978年 | 11篇 |
1977年 | 4篇 |
1976年 | 3篇 |
1974年 | 2篇 |
1972年 | 4篇 |
1967年 | 2篇 |
排序方式: 共有779条查询结果,搜索用时 15 毫秒
1.
Yuki Shintani Taku Ohtomi Dr. Aya Shibata Dr. Yoshiaki Kitamura Koichiro M. Hirosawa Prof. Kenichi G. N. Suzuki Prof. Masato Ikeda 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(8):e202104421
Aqueous self-assembly of short peptides has attracted growing attention for the construction of supramolecular materials for various bioapplications. Herein, we describe how the thermolysin-assisted biocatalytic construction of a dipeptide hydrazide from an N-protected amino acid and an amino acid hydrazide leads to the formation of thermally stable supramolecular hydrogels. In addition, we demonstrate the post-assembly modification of the supramolecular architectures constructed in situ tethering hydrazide groups as a chemical handle by means of fluorescence imaging. 相似文献
2.
Tsuyoshi Kitamura 《Tetrahedron》2004,60(43):9649-9657
Synthesis of (+)-anthramycin was examined. A pyrrolobenzodiazepine skeleton could be synthesized by reductive cyclization of pyrrolidine derivative, which was obtained by enyne metathesis. The conjugated enamide ester part of (+)-anthramycin derivative was constructed by cross-metathesis. 相似文献
3.
Toshiyuki Oyama Akira Kitamura Eiichi Sato Masao Tomoi 《Journal of polymer science. Part A, Polymer chemistry》2006,44(8):2694-2706
The factors affecting pattern‐forming properties in reaction development patterning were examined with polyarylates with various bisphenol moieties. The developability of the photosensitive polyarylates was dependent on the properties of the subtituent (R) in the bisphenol moieties. The development time decreased in the following order: R?C(CH3)2 > fluorenyl unit ? phenolphthalein unit > C(CF3)2 > SO2. This order agreed with that of the reactivity between the polyarylates and ethanolamine, and these orders can be explained by pKa of the bisphenol used to prepare the polyarylates. The development with NH2? R′? OH resulted in successful positive‐tone pattern formation. However, pattern formation with the developers containing NH2? R′? OCH3 was unsuccessful. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2694–2706, 2006 相似文献
4.
5.
6.
Quantum yields, lifetimes and shapes of fluorescence from polymers containing the trans-1,2-dicarbazolylcyclobutane (DCZB) or carbazolyl structures were studied in N,N-dimethylformamide. No sandwich-type excimer formation was observed for DCZB polymers. The so-called second excimer observed in poly(9-vinylcarbazole) might also be produced in poly(9-ethyl-3-vinylcarbazole). 相似文献
7.
Nishida H Miyazaki Y Kitamura Y Ohashi M Matsusue T Okamoto A Hosaka Y Ohnishi S Mochizuki H 《Chemical & pharmaceutical bulletin》2001,49(10):1237-1244
Intravascular clot formation is an important factor in a number of cardiovascular diseases. Therefore, the prevention of blood coagulation has become a major target for new therapeutic agents. One attractive approach is the inhibition of factor Xa (FXa), which is a key enzyme in coagulation cascade responsible for the generation of thrombin by limited proteolysis of its zymogen, prothrombin. We have investigated 1-arylsulfonyl-3-piperazinone derivatives, containing a 4-(piperidino)pyridine group in place of guanidino and/or amidino groups, and discovered compound M55113 (30a: 4-[(6-Chloro-2-naphthalenyl)sulfonyl]-1-[[1-(4-pyridinyl)-4-piperidinyl]methyl]piperazinone), as a potent inhibitor of FXa (IC50=0.06 microM) with high selectivity for FXa over trypsin and thrombin. 相似文献
8.
9.
The functionalized pyranosyl hetero-olefins , and received a remarkable diastereoselective addition of methyllithium to form adducts, one of which was introduced into a possible synthetic intermediate as for maytansine () along Scheme I. 相似文献
10.