全文获取类型
收费全文 | 677篇 |
免费 | 33篇 |
国内免费 | 22篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 57篇 |
妇产科学 | 31篇 |
基础医学 | 86篇 |
口腔科学 | 18篇 |
临床医学 | 115篇 |
内科学 | 122篇 |
皮肤病学 | 13篇 |
神经病学 | 21篇 |
特种医学 | 109篇 |
外科学 | 48篇 |
综合类 | 7篇 |
预防医学 | 38篇 |
药学 | 45篇 |
中国医学 | 1篇 |
肿瘤学 | 19篇 |
出版年
2021年 | 4篇 |
2019年 | 8篇 |
2018年 | 4篇 |
2017年 | 7篇 |
2016年 | 7篇 |
2015年 | 7篇 |
2014年 | 11篇 |
2013年 | 25篇 |
2012年 | 13篇 |
2011年 | 27篇 |
2010年 | 34篇 |
2009年 | 24篇 |
2008年 | 20篇 |
2007年 | 28篇 |
2006年 | 16篇 |
2005年 | 15篇 |
2004年 | 7篇 |
2003年 | 10篇 |
2002年 | 15篇 |
2001年 | 18篇 |
2000年 | 8篇 |
1999年 | 26篇 |
1998年 | 42篇 |
1997年 | 46篇 |
1996年 | 39篇 |
1995年 | 20篇 |
1994年 | 26篇 |
1993年 | 17篇 |
1992年 | 18篇 |
1991年 | 14篇 |
1990年 | 10篇 |
1989年 | 19篇 |
1988年 | 34篇 |
1987年 | 15篇 |
1986年 | 11篇 |
1985年 | 9篇 |
1984年 | 11篇 |
1983年 | 8篇 |
1982年 | 14篇 |
1981年 | 10篇 |
1980年 | 8篇 |
1978年 | 3篇 |
1977年 | 6篇 |
1976年 | 4篇 |
1975年 | 4篇 |
1954年 | 2篇 |
1952年 | 1篇 |
1948年 | 1篇 |
1947年 | 1篇 |
1943年 | 1篇 |
排序方式: 共有732条查询结果,搜索用时 15 毫秒
1.
Reversal of sterilisation by the railroad technique 总被引:1,自引:0,他引:1
L. C. Edozien Senior Registrar D. Anastassopulos Staff Grade A. M. Mander Consultant 《BJOG : an international journal of obstetrics and gynaecology》1997,104(1):92-95
Objective To show that a simple, easily learned and relatively inexpensive method of reversal of sterilisation provides good results.
Design Retrospective observational study.
Setting An NHS Trust Hospital.
Sample Sixty-seven women aged 19 to 39 years who underwent reversal of sterilisation between January 1984 and December 1993.
Main outcome measures Pregnancy rate following reversal; rate of ectopic pregnancy.
Results Thirty-four women (51%) had intrauterine pregnancies after reversal of sterilisation; intrauterine pregnancy rate in women who had been sterilised with rings or clips was 64%. Five women (7.5%) had ectopic pregnancies.
Conclusion This technique provides results that compare favourably with those of microsurgery. It offers hope to couples who do not meet the restrictive criteria for microsurgery and in vitro fertilisation and should appeal to purchasing authorities. 相似文献
Design Retrospective observational study.
Setting An NHS Trust Hospital.
Sample Sixty-seven women aged 19 to 39 years who underwent reversal of sterilisation between January 1984 and December 1993.
Main outcome measures Pregnancy rate following reversal; rate of ectopic pregnancy.
Results Thirty-four women (51%) had intrauterine pregnancies after reversal of sterilisation; intrauterine pregnancy rate in women who had been sterilised with rings or clips was 64%. Five women (7.5%) had ectopic pregnancies.
Conclusion This technique provides results that compare favourably with those of microsurgery. It offers hope to couples who do not meet the restrictive criteria for microsurgery and in vitro fertilisation and should appeal to purchasing authorities. 相似文献
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.
Aiste Jekabsone Palwinder K Mander Anna Tickler Martyn Sharpe Guy C Brown 《Journal of neuroinflammation》2006,3(1):24-13
Background
Alzheimer's disease is characterized by the accumulation of neuritic plaques, containing activated microglia and β-amyloid peptides (Aβ). Fibrillar Aβ can activate microglia, resulting in production of toxic and inflammatory mediators like hydrogen peroxide, nitric oxide, and cytokines. We have recently found that microglial proliferation is regulated by hydrogen peroxide derived from NADPH oxidase. Thus, in this study, we investigated whether Aβ can stimulate microglial proliferation and cytokine production via activation of NADPH oxidase to produce hydrogen peroxide. 相似文献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.
10.
It is well recognized that the ability to cryopreserve unfertilizedhuman oocytes would make a significant contribution to infertilitytreatment. However, despite considerable interest, very fewsuccessful pregnancies have arisen from cryopreserved oocytesafter thawing, insemination and transfer of the subsequent embryo.The reasons for this lack of progress may well result from adearth of information on how the various biophysical changesduring a cryopreservation regimen affect human oocyte function.Recently, fundamental studies on the effects of cooling, membranepermeability, cryoprotectant addition and ice formation havebeen performed on human oocytes by a number of groups, and theseform the basis of the current review. It is likely that successfulhuman oocyte cryopreservation will only follow once these factorsare fully understood, but the existing base of knowledge shouldprovide a platform for further improvements in the techniquescurrently employed. 相似文献