全文获取类型
收费全文 | 608篇 |
免费 | 35篇 |
国内免费 | 22篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 66篇 |
基础医学 | 89篇 |
口腔科学 | 13篇 |
临床医学 | 89篇 |
内科学 | 152篇 |
皮肤病学 | 16篇 |
神经病学 | 3篇 |
特种医学 | 108篇 |
外科学 | 41篇 |
综合类 | 9篇 |
预防医学 | 26篇 |
药学 | 30篇 |
肿瘤学 | 22篇 |
出版年
2022年 | 2篇 |
2020年 | 2篇 |
2019年 | 8篇 |
2018年 | 7篇 |
2017年 | 4篇 |
2016年 | 5篇 |
2015年 | 5篇 |
2014年 | 15篇 |
2013年 | 19篇 |
2012年 | 13篇 |
2011年 | 18篇 |
2010年 | 30篇 |
2009年 | 19篇 |
2008年 | 14篇 |
2007年 | 42篇 |
2006年 | 14篇 |
2005年 | 21篇 |
2004年 | 9篇 |
2003年 | 7篇 |
2002年 | 11篇 |
2001年 | 9篇 |
2000年 | 9篇 |
1999年 | 15篇 |
1998年 | 42篇 |
1997年 | 42篇 |
1996年 | 36篇 |
1995年 | 18篇 |
1994年 | 27篇 |
1993年 | 18篇 |
1992年 | 14篇 |
1991年 | 10篇 |
1990年 | 9篇 |
1989年 | 11篇 |
1988年 | 30篇 |
1987年 | 11篇 |
1986年 | 10篇 |
1985年 | 7篇 |
1984年 | 11篇 |
1983年 | 10篇 |
1982年 | 14篇 |
1981年 | 9篇 |
1980年 | 6篇 |
1978年 | 4篇 |
1977年 | 5篇 |
1976年 | 4篇 |
1975年 | 2篇 |
1954年 | 2篇 |
1909年 | 1篇 |
1871年 | 1篇 |
1869年 | 1篇 |
排序方式: 共有665条查询结果,搜索用时 15 毫秒
1.
2.
Factors influencing women to undergo screening mammography 总被引:2,自引:0,他引:2
3.
Braffman BH; Coleman BG; Ramchandani P; Arger PH; Nodine CF; Dinsmore BJ; Louie A; Betsch SE 《Radiology》1994,190(3):797
4.
5.
Rupture of the distal biceps tendon: evaluation with MR imaging 总被引:2,自引:0,他引:2
6.
7.
Androgen receptor YAC transgenic mice carrying CAG 45 alleles show trinucleotide repeat instability 总被引:1,自引:15,他引:1
La Spada AR; Peterson KR; Meadows SA; McClain ME; Jeng G; Chmelar RS; Haugen HA; Chen K; Singer MJ; Moore D; Trask BJ; Fischbeck KH; Clegg CH; McKnight GS 《Human molecular genetics》1998,7(6):959-967
X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG
repeat expansion in the first exon of the androgen receptor (AR) gene.
Disease-associated alleles (37-66 CAGs) change in length when transmitted
from parents to offspring, with a significantly greater tendency to shift
size when inherited paternally. As transgenic mice carrying human AR cDNAs
with 45 and 66 CAG repeats do not display repeat instability, we attempted
to model trinucleotide repeat instability by generating transgenic mice
with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions
in their genomic context. Studies of independent lines of AR YAC transgenic
mice with CAG 45 alleles reveal intergenerational instability at an overall
rate of approximately 10%. We also find that the 45 CAG repeat tracts are
significantly more unstable with maternal transmission and as the
transmitting mother ages. Of all the CAG/CTG repeat transgenic mice
produced to date the AR YAC CAG 45 mice are unstable with the smallest
trinucleotide repeat mutations, suggesting that the length threshold for
repeat instability in the mouse may be lowered by including the appropriate
flanking human DNA sequences. By sequence-tagged site content analysis and
long range mapping we determined that one unstable transgenic line has
integrated an approximately 70 kb segment of the AR locus due to
fragmentation of the AR YAC. Identification of the cis - acting elements
that permit CAG tract instability and the trans -acting factors that
modulate repeat instability in the AR YAC CAG 45 mice may provide insights
into the molecular basis of trinucleotide repeat instability in humans.
相似文献
8.
9.
Arjan C. Lankester Gijs M. W. Van Schijndel Pauline M. L. Rood Arthur J. Verhoeven Ren A. W. Van Lier 《European journal of immunology》1994,24(11):2818-2825
The SH2 domain-containing transforming Shc protein has been implicated in mitogenic signaling via several surface receptors through p21ras. Following tyrosine phosphorylation by either receptor or non-receptor tyrosine kinases, Shc may interact with the adaptor protein Grb2, which is linked to Sos1, a guanine nucleotide exchange factor for human ras. Ligation of the antigen receptor complex on B cells (BCR) is known to activate various intracellular signaling pathways, which may accumulate in mitogenic responses. With respect to the initial steps, the activation of BCR-associated non-receptor tyrosine kinases appears to be indispensible. In this report we show that Shc proteins become tyrosine phosphorylated after BCR ligation on both transformed and normal human B cells. This is accompanied by the association of Shc with Grb2 proteins and a yet unidentified 145-kDa tyrosine phosphorylated protein. Subcellular fractionation revealed that this activation-induced multimeric Shc complex rapidly translocates towards the plasma membrane. Co-ligation of the BCR with the CD19 molecule results in a marked increase of these events, whereas CD19 cross-linking alone does not induce Shc tyrosine phosphorylation or translocation. Thus, in B cells the Shc complex may represent a molecular junction between the BCR and the mitogenic p21ras cascade. 相似文献
10.