全文获取类型
收费全文 | 1392篇 |
免费 | 3篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 2篇 |
化学工业 | 30篇 |
金属工艺 | 14篇 |
机械仪表 | 1篇 |
建筑科学 | 2篇 |
矿业工程 | 3篇 |
轻工业 | 12篇 |
水利工程 | 2篇 |
石油天然气 | 36篇 |
无线电 | 6篇 |
一般工业技术 | 35篇 |
冶金工业 | 1238篇 |
原子能技术 | 5篇 |
自动化技术 | 10篇 |
出版年
2022年 | 2篇 |
2021年 | 3篇 |
2018年 | 4篇 |
2017年 | 3篇 |
2016年 | 6篇 |
2015年 | 7篇 |
2014年 | 7篇 |
2013年 | 6篇 |
2012年 | 4篇 |
2011年 | 5篇 |
2010年 | 4篇 |
2009年 | 2篇 |
2008年 | 7篇 |
2007年 | 6篇 |
2006年 | 3篇 |
2005年 | 6篇 |
2003年 | 6篇 |
2002年 | 5篇 |
2001年 | 9篇 |
2000年 | 4篇 |
1999年 | 29篇 |
1998年 | 330篇 |
1997年 | 227篇 |
1996年 | 157篇 |
1995年 | 109篇 |
1994年 | 65篇 |
1993年 | 74篇 |
1992年 | 11篇 |
1991年 | 25篇 |
1990年 | 8篇 |
1989年 | 9篇 |
1988年 | 6篇 |
1987年 | 9篇 |
1986年 | 4篇 |
1985年 | 6篇 |
1984年 | 2篇 |
1983年 | 3篇 |
1982年 | 5篇 |
1981年 | 12篇 |
1980年 | 16篇 |
1979年 | 5篇 |
1978年 | 7篇 |
1977年 | 47篇 |
1976年 | 98篇 |
1973年 | 3篇 |
1972年 | 8篇 |
1971年 | 8篇 |
1969年 | 2篇 |
1967年 | 2篇 |
1966年 | 2篇 |
排序方式: 共有1396条查询结果,搜索用时 0 毫秒
31.
32.
33.
34.
P Lipponen S Aaltomaa M Eskelinen M Ala-Opas VM Kosma 《Canadian Metallurgical Quarterly》1998,34(3):237-243
Selective antagonists to the Type 3 serotonin receptor (5HT3) in combination with corticosteroids are now considered the standard of care for the prevention of emesis from moderately to highly emetogenic chemotherapy. Here we address issues of optimal dose, schedule and route of administration of four currently available selectable 5HT3 antagonists. This paper utilizes an evidence based medicine approach to the literature regarding this class of drugs, emphasizing the results large, randomized, controlled trials to make formal recommendations concerning optimal use of this important new class of anti-emetic agents. We conclude that for each drug there is a plateau in therapeutic efficacy at a definable dose level above which further dose escalation does not improve outcome. Furthermore, a single dose is as effective as multiple doses or continuous infusion, and finally, emerging data demonstrate that the oral route is equally efficacious as the intravenous route of administration, even with highly emetogenic chemotherapy. 相似文献
35.
36.
37.
38.
Trifluoroethanol (TFE) is often used to increase the helicity of peptides to make them usable as models of helices in proteins. We have measured helix propensities for all 20 amino acids in water and two concentrations of trifluoroethanol, 15 and 40% (v/v) using, as a model system, a peptide derived from the sequence of the alpha-helix of ribonuclease T1. There are three main conclusions from our studies. (1) TFE alters electrostatic interactions in the ribonuclease T1 helical peptide such that the dependence of the helical content on pH is lost in 40% TFE. (2) Helix propensities measured in 15% TFE correlate well with propensities measured in water, however, the correlation with propensities measured in 40% TFE is significantly worse. (3) Propensities measured in alanine-based peptides and the ribonuclease T1 peptide in TFE show very poor agreement, revealing that TFE greatly increases the effect of sequence context. 相似文献
39.
40.
E. I. Medvedeva 《Automatic Documentation and Mathematical Linguistics》2008,42(3):177-188
This paper examines the functioning of a saturated consumer market and the contemporary concept of marketing. It describes
the features of an information product which cardinally distinguish it from other goods and analyzes a new form of interactive
marketing, i.e., electronic marketing. The instruments of electronic commerce and structure of the contemporary information
market are analyzed. 相似文献