全文获取类型
收费全文 | 756篇 |
免费 | 4篇 |
国内免费 | 17篇 |
专业分类
安全科学 | 12篇 |
环保管理 | 17篇 |
综合类 | 676篇 |
基础理论 | 30篇 |
环境理论 | 2篇 |
污染及防治 | 17篇 |
评价与监测 | 6篇 |
社会与环境 | 10篇 |
灾害及防治 | 7篇 |
出版年
2023年 | 2篇 |
2022年 | 2篇 |
2021年 | 7篇 |
2020年 | 8篇 |
2018年 | 3篇 |
2017年 | 4篇 |
2016年 | 5篇 |
2015年 | 2篇 |
2014年 | 4篇 |
2013年 | 19篇 |
2012年 | 20篇 |
2011年 | 80篇 |
2010年 | 69篇 |
2009年 | 53篇 |
2008年 | 53篇 |
2007年 | 59篇 |
2006年 | 52篇 |
2005年 | 53篇 |
2004年 | 50篇 |
2003年 | 52篇 |
2002年 | 46篇 |
2001年 | 30篇 |
1999年 | 2篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 36篇 |
1994年 | 29篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 4篇 |
1989年 | 3篇 |
1988年 | 4篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1984年 | 6篇 |
1983年 | 4篇 |
1982年 | 1篇 |
1979年 | 1篇 |
排序方式: 共有777条查询结果,搜索用时 109 毫秒
401.
402.
Prakesh S. Shah Susan Blaser Ants Toi Katherine Fong Phyllis Glanc Riyana Babul-Hirji James Rutka David Chitayat 《黑龙江环境通报》2005,25(7):539-542
We describe the finding of cavum veli interpositi (CVI) on fetal ultrasound and MRI and the postnatal MRI and developmental follow-up in two cases. The first case was diagnosed on fetal ultrasound at 33 weeks' gestation and confirmed on fetal MRI. No abnormalities were detected on postnatal examinations and the brain MRI at 1 year of age showed no changes. At 4 years of age, his growth and development were normal. The second case was diagnosed with CVI on fetal ultrasound and MRI at 33.5 weeks' gestation. Postnatal examination showed no abnormalities, and brain MRI at 8 months of age revealed that the CVI was unchanged, but there was a dilated cavum septum pellucidum and cavum vergae. Her growth and development during the first 4 years of life were normal. CVI is a rare fetal ultrasound finding, which seems to be benign. However, further neurodevelopmental follow-up is needed to confirm this observation. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
403.
404.
Lethal multiple pterygium syndrome is a rare inherited disorder. Previous reports suggest that the diagnosis may be based on prenatal sonographic demonstration of severe limb flexion, absence of fetal motion, and a large cystic hygroma in the second and third trimesters. We present the sonographic features and postmortem features of a fetus with lethal multiple pterygium syndrome at 13 weeks of gestation, which shows that the condition can possibly be diagnosed in the first trimester of pregnancy. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
405.
406.
407.
408.
409.
410.