全文获取类型
收费全文 | 612篇 |
免费 | 1篇 |
国内免费 | 3篇 |
专业分类
综合类 | 615篇 |
基础理论 | 1篇 |
出版年
2021年 | 6篇 |
2016年 | 1篇 |
2015年 | 1篇 |
2012年 | 14篇 |
2011年 | 72篇 |
2010年 | 59篇 |
2009年 | 46篇 |
2008年 | 37篇 |
2007年 | 49篇 |
2006年 | 44篇 |
2005年 | 44篇 |
2004年 | 43篇 |
2003年 | 41篇 |
2002年 | 39篇 |
2001年 | 27篇 |
1995年 | 36篇 |
1994年 | 28篇 |
1993年 | 2篇 |
1992年 | 4篇 |
1991年 | 2篇 |
1990年 | 6篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 4篇 |
1983年 | 3篇 |
排序方式: 共有616条查询结果,搜索用时 299 毫秒
531.
Françoise Muller Didier Thibaud Françoise Poloce Marie-Christine Gelineau Marguerite Bernard Christine Brochet Christine Millet Jean-Yves Réal Marc Dommergues 《黑龙江环境通报》2002,22(11):1036-1039
In routine obstetrical practice, prior to offering invasive prenatal diagnosis, it is crucial to weigh the risks attendant on amniocentesis against the individual's risk of aneuploidy. We took advantage of a policy of follow-up of patients undergoing Down syndrome maternal serum screening to compare the rates of fetal loss before 24 weeks and of early premature delivery at 24–28 weeks between women who underwent amniocentesis and women who did not. A total of 54 902 patients entered the study, of whom 4039 (7.35%) were lost to follow-up and 387 were excluded because of a severe fetal abnormality. Of the 50 476 remaining patients, 3472 had an amniocentesis whereas 47 004 had not and served as controls. In the amniocentesis group, the fetal loss rate before 24 weeks was 1.12% (95% CI=1.08–1.15) and the 24–28 weeks premature delivery rate was 0.40% (95% CI=0.39–0.41) which was significantly higher than in controls (0.42% with 95% CI 0.41–0.43 and 0.24% with 95% CI 0.23–0.25, respectively). The 0.86% difference in adverse outcome rates between the amniocentesis and control groups may be attributable to amniocentesis and compares favourably with the positive predictive value of maternal serum markers (1.70%) observed in the present study. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
532.
533.
534.
535.
536.
537.
538.
539.
540.