全文获取类型
收费全文 | 1500篇 |
免费 | 184篇 |
国内免费 | 1篇 |
出版年
2021年 | 19篇 |
2020年 | 13篇 |
2019年 | 17篇 |
2018年 | 21篇 |
2017年 | 24篇 |
2016年 | 32篇 |
2015年 | 45篇 |
2014年 | 60篇 |
2013年 | 77篇 |
2012年 | 82篇 |
2011年 | 83篇 |
2010年 | 65篇 |
2009年 | 46篇 |
2008年 | 77篇 |
2007年 | 49篇 |
2006年 | 58篇 |
2005年 | 60篇 |
2004年 | 49篇 |
2003年 | 58篇 |
2002年 | 45篇 |
2001年 | 49篇 |
2000年 | 38篇 |
1999年 | 23篇 |
1998年 | 15篇 |
1997年 | 12篇 |
1996年 | 19篇 |
1995年 | 13篇 |
1994年 | 15篇 |
1992年 | 36篇 |
1991年 | 37篇 |
1990年 | 22篇 |
1989年 | 25篇 |
1988年 | 23篇 |
1987年 | 25篇 |
1986年 | 23篇 |
1985年 | 23篇 |
1984年 | 29篇 |
1983年 | 25篇 |
1982年 | 21篇 |
1981年 | 12篇 |
1980年 | 13篇 |
1979年 | 18篇 |
1977年 | 15篇 |
1976年 | 11篇 |
1974年 | 14篇 |
1973年 | 15篇 |
1972年 | 22篇 |
1970年 | 9篇 |
1968年 | 8篇 |
1966年 | 13篇 |
排序方式: 共有1685条查询结果,搜索用时 109 毫秒
1.
Purification and partial characterization of a bovine epidermal growth factor-like polypeptide 总被引:1,自引:0,他引:1
J C Byatt B R Larson M P Baganoff M F McGrath R J Collier 《Biochemistry international》1990,20(6):1179-1187
A heterologous radioreceptor assay was developed to follow the purification of an EGF-like polypeptide from bovine kidney. Purification of the growth factor was facilitated by the use of a novel affinity column using fixed A431 cells attached to sephadex beads. The mol. wt. of the purified EGF-LP was estimated to be 5480 from the amino acid composition. The purified EGF-like polypeptide stimulated the proliferation of bovine mammary epithelial cells and appeared to be equipotent to mouse EGF. Available evidence suggests that the purified molecule is distinct from bovine TGF-alpha. 相似文献
2.
3.
A “double-blepharoplast” originates de novo in the spermatogenous cell of Ginkgo biloba L. Initially, the double-blepharoplast consists of two opposing hemispherical bodies comprised of densely staining material. The two blepharoplasts seemingly are pushed apart by the formation of densely packed fibrils which are oriented perpendicular to the distal, rounded edges of the two future blepharoplasts. As the latter move apart, each one develops lightly staining channels which are often organized in a hub and spoke configuration (procentrioles). Microtubules extend from the blepharoplasts as the latter move to their final position in the cell, and centrioles (probasal bodies) become organized at the periphery of each blepharoplast. Two large “osmiophilic globules,” conspicuous entities close to the nucleus of the mature spermatogenous cell, arise de novo. A fibrillogranular body in the cytoplasm, always closely associated with the nucleus, also arises de novo. 相似文献
4.
Physicians with an interest in pain have long suggested that the poor complain more and have a higher prevalence of neuroticism than do higher social groups. This assumption was tested by analysing the pain patterns in 500 consecutive patients attending a pain relief clinic. Results implied that scores for presenting pain, anxiety, and depression were similar to all social groups. After treatment scores for residual pain were significantly lower in all social classes, with greatest reduction in classes III, IV, and V. Almost identical results were obtained in a subgroup of patients with cancer but not in a subgroup with sciatica. That patients from the lower social classes have a higher perception of pain and are more neurotic than other group is a myth, probably resulting from poor communication between clinicians and patients of dissimilar socioeconomic class. 相似文献
5.
6.
Schoene R. B.; Bates P. W.; Larson E. B.; Pierson D. J. 《Journal of applied physiology》1983,55(6):1772-1776
7.
8.
Globin synthesis on reticulocyte membrane-bound ribosomes 总被引:1,自引:0,他引:1
W R Woodward S D Adamson H M McQueen J W Larson S M Estvanik P Wilairat E Herbert 《The Journal of biological chemistry》1973,248(5):1556-1561
9.
Jon S Larson Moying Yin Jared M Fischer Saundra L Stringer James R Stringer 《BMC molecular biology》2006,7(1):36
Background
Loss of heterozygosity (LOH) contributes to many cancers, but the rate at which these events occur in normal cells of the body is not clear. LOH would be detectable in diverse cell types in the body if this event were to confer an obvious cellular phenotype. Mice that carry two different fluorescent protein genes as alleles of a locus would seem to be a useful tool for addressing this issue because LOH would change a cell's phenotype from dichromatic to monochromatic. In addition, LOH caused by mitotic crossing over might be discernable in tissues because this event produces a pair of neighboring monochromatic cells that are different colors. 相似文献10.