全文获取类型
收费全文 | 18213篇 |
免费 | 1825篇 |
国内免费 | 7篇 |
出版年
2022年 | 163篇 |
2021年 | 316篇 |
2020年 | 198篇 |
2019年 | 275篇 |
2018年 | 370篇 |
2017年 | 295篇 |
2016年 | 527篇 |
2015年 | 829篇 |
2014年 | 883篇 |
2013年 | 1073篇 |
2012年 | 1317篇 |
2011年 | 1231篇 |
2010年 | 843篇 |
2009年 | 682篇 |
2008年 | 989篇 |
2007年 | 916篇 |
2006年 | 853篇 |
2005年 | 765篇 |
2004年 | 803篇 |
2003年 | 658篇 |
2002年 | 633篇 |
2001年 | 345篇 |
2000年 | 307篇 |
1999年 | 262篇 |
1998年 | 189篇 |
1997年 | 154篇 |
1996年 | 131篇 |
1995年 | 132篇 |
1994年 | 136篇 |
1993年 | 122篇 |
1992年 | 194篇 |
1991年 | 203篇 |
1990年 | 191篇 |
1989年 | 203篇 |
1988年 | 177篇 |
1987年 | 167篇 |
1986年 | 157篇 |
1985年 | 153篇 |
1984年 | 128篇 |
1983年 | 111篇 |
1982年 | 121篇 |
1981年 | 126篇 |
1980年 | 104篇 |
1979年 | 114篇 |
1978年 | 114篇 |
1977年 | 78篇 |
1976年 | 96篇 |
1975年 | 106篇 |
1974年 | 106篇 |
1973年 | 98篇 |
排序方式: 共有10000条查询结果,搜索用时 171 毫秒
201.
A medium consisting of an aqueous extract of zein, lactose, and Tween 80 is used together with an overlay of 1 % Tween 80 and coverslipping to provide a combined rapid (germ tube) and standard (chlamydospore) method for diagnosis ofCandida albicans. The method is exquisitely sensitive for diagnosis ofC. albicans but lumps chlamydospore-producing strains ofC. tropicalis withC. albicans. 相似文献
202.
203.
204.
205.
206.
207.
208.
THE METABOLISM OF PALMITIC ACID IN THE PHOSPHOLIPIDS, NEUTRAL GLYCERIDES AND GALACTOLIPIDS OF MOUSE BRAIN 总被引:6,自引:4,他引:2
Abstract— Following intracerebral injection, [14 C]palmitic acid was rapidly incorporated into a variety of brain lipids. After 12 hr, 78 per cent of the lipid radioactivity was in phospholipids, 15 per cent was in triacylglycerols, 1 per cent each was in free fatty acids and galactolipids, and the remainder was in other neutral glycerides. Over 65 per cent of the phospholipid radioactivity was found in the choline phosphoglycerides but this proportion decreased substantially with time. At later times, increasing portions of the radioactivity were present in the monounsaturated acyl groups and the alkenyl groups but no radioactivity was detected in cholesterol or polyunsaturated acyl groups. These results indicate that most of the extensive recycling of radioactivity took place without oxidative degradation of the palmitoyl groups. The relative rates of incorporation of radioactivity were compared at 12 hr after injection. The specific radioactivities of the serine, ethanolamine, and choline phosphoglycerides had ratios of 6:3:2 based on the palmitoyl group content and 1:2:4 based on their phosphorus content. The specific radioactivities of galactolipids with O -acyl groups were higher than the specific radioactivitiesof cerebrosides or cerebroside sulphates. A new solvent mixture for thin-layer chromatography of brain galactolipids was described (chloroform-acetone-methanol-water, 60:20:20:1, by vol.). 相似文献
209.
Lysogenic Conversion in Bacillus amyloliquefaciens H Affecting Viral Adsorption 总被引:3,自引:2,他引:1
下载免费PDF全文
![点击此处可从《Journal of virology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Lysogenization of Bacillus amyloliquefaciens H with bacteriophage PK renders the bacteria resistant to superinfection with bacteriophage of PK type. 相似文献
210.
Detection and localization of antibody-forming cells to a bacterial endotoxin by an immunobioautographic procedure 总被引:1,自引:0,他引:1