全文获取类型
收费全文 | 808篇 |
免费 | 16篇 |
国内免费 | 2篇 |
专业分类
化学 | 685篇 |
晶体学 | 4篇 |
力学 | 6篇 |
数学 | 80篇 |
物理学 | 51篇 |
出版年
2022年 | 4篇 |
2021年 | 8篇 |
2020年 | 9篇 |
2019年 | 13篇 |
2017年 | 4篇 |
2016年 | 22篇 |
2015年 | 20篇 |
2014年 | 18篇 |
2013年 | 44篇 |
2012年 | 40篇 |
2011年 | 46篇 |
2010年 | 34篇 |
2009年 | 34篇 |
2008年 | 42篇 |
2007年 | 44篇 |
2006年 | 30篇 |
2005年 | 37篇 |
2004年 | 36篇 |
2003年 | 35篇 |
2002年 | 20篇 |
2001年 | 10篇 |
2000年 | 11篇 |
1999年 | 10篇 |
1998年 | 10篇 |
1997年 | 10篇 |
1996年 | 6篇 |
1995年 | 7篇 |
1994年 | 7篇 |
1993年 | 8篇 |
1992年 | 9篇 |
1991年 | 6篇 |
1990年 | 16篇 |
1989年 | 5篇 |
1988年 | 9篇 |
1987年 | 11篇 |
1986年 | 14篇 |
1985年 | 14篇 |
1984年 | 13篇 |
1983年 | 9篇 |
1982年 | 17篇 |
1981年 | 7篇 |
1980年 | 12篇 |
1979年 | 10篇 |
1978年 | 5篇 |
1977年 | 9篇 |
1976年 | 7篇 |
1973年 | 6篇 |
1972年 | 4篇 |
1971年 | 4篇 |
1968年 | 5篇 |
排序方式: 共有826条查询结果,搜索用时 881 毫秒
51.
Dautrey Sébastien Bodiguel Jacques Arrault Axelle Jamart-Grégoire Brigitte 《Tetrahedron》2012,68(23):4362-4367
1H NMR and FTIR experiments performed on the 1:1[α:α-N-amino]mers series let us to point out a rare NH–π interaction between the carbamidic NH of the i residue and the phenyl group of a phenylalanine residue located at i+2. 相似文献
52.
53.
Marie-Pierre Oury Rollande Dumont Catherine Jurie Jean-François Hocquette Brigitte Picard 《BMC biochemistry》2010,11(1):12
Background
An important variability of contractile and metabolic properties between muscles has been highlighted. In the literature, the majority of studies on beef sensorial quality concerns M. longissimus thoracis. M. rectus abdominis (RA) is easy to sample without huge carcass depreciation and may appear as an alternative to M. longissimus thoracis for fast and routine physicochemical analysis. It was considered interesting to assess the muscle fibres of M. rectus abdominis in comparison with M. longissimus thoracis (LT) and M. triceps brachii (TB) on the basis of metabolic and contractile properties, area and myosin heavy chain isoforms (MyHC) proportions. Immuno-histochemical, histochemical, histological and enzymological techniques were used. This research concerned two populations of Charolais cattle: RA was compared to TB in a population of 19 steers while RA was compared to LT in a population of 153 heifers. 相似文献54.
Bibal B Tinant B Declercq JP Dutasta JP 《Chemical communications (Cambridge, England)》2002,(5):432-433
The new tetra-thiophosphonatocavitand 1 in its iiii configuration extracts quantitatively Ag+ ions from aqueous solutions; the tetranuclear complex [1(2).Ag4Pic4] was selectively formed and characterized in the solid state by X-ray diffraction which revealed the formation of a new dimeric assembly through Ag+ coordination. 相似文献
55.
Brigitte Servatius 《Mathematische Zeitschrift》1983,184(1):133-137
56.
57.
58.
Background
We explored spatio-temporal patterns of cortical activity evoked by written words from super-ordinate and sub-ordinate semantic categories and hoped to find a differential cortical and/or temporal distribution of the brain response depending on the level of the categories. Twenty-three subjects saw 360 words belonging to six sub-ordinate categories (mammals, birds, fish, fruit, flowers, trees) within two super-ordinate categories (fauna, flora). Visually evoked magnetic fields were determined from whole-head (148-sensor) magnetoencephalography and analyzed in the source space (Minimum Norm Estimate). 相似文献59.
El Oualid F van den Elst H Leroy IM Pieterman E Cohen LH Burm BE Overkleeft HS van der Marel GA Overhand M 《Journal of combinatorial chemistry》2005,7(5):703-713
A combinatorial synthesis of oligopeptide analogues and their evaluation as protein:geranylgeranyl transferase inhibitors is presented. The combinatorial strategy is based on the random mutation, in each new generation, of one of any of the four amino acid building blocks of which the most effective compounds of the previous generation are assembled. In this way, a progressive improvement of the average inhibitory activity was observed until the fifth generation. The most active inhibitors were found to inhibit PGGT-1 in the low micromolar range (IC(50): 3.8-8.1 microM). 相似文献
60.
[reaction: see text]. (-)-PF1163B, a new macrocyclic antifungal antibiotic isolated from Streptomyces sp., has been prepared in eight steps from (S)-citronellene. The key step is a ring-closing metathesis reaction of an ester and amide derivative obtained from a substituted N-methyl-l-tyrosine. 相似文献