全文获取类型
收费全文 | 44522篇 |
免费 | 474篇 |
国内免费 | 357篇 |
专业分类
安全科学 | 1346篇 |
废物处理 | 2026篇 |
环保管理 | 6112篇 |
综合类 | 7064篇 |
基础理论 | 11944篇 |
环境理论 | 18篇 |
污染及防治 | 10464篇 |
评价与监测 | 3021篇 |
社会与环境 | 3065篇 |
灾害及防治 | 293篇 |
出版年
2022年 | 334篇 |
2021年 | 394篇 |
2020年 | 271篇 |
2019年 | 336篇 |
2018年 | 934篇 |
2017年 | 951篇 |
2016年 | 1256篇 |
2015年 | 748篇 |
2014年 | 1076篇 |
2013年 | 3426篇 |
2012年 | 1487篇 |
2011年 | 2278篇 |
2010年 | 1704篇 |
2009年 | 1812篇 |
2008年 | 2212篇 |
2007年 | 2337篇 |
2006年 | 1625篇 |
2005年 | 1444篇 |
2004年 | 1381篇 |
2003年 | 1382篇 |
2002年 | 1305篇 |
2001年 | 1473篇 |
2000年 | 1065篇 |
1999年 | 661篇 |
1998年 | 530篇 |
1997年 | 505篇 |
1996年 | 551篇 |
1995年 | 628篇 |
1994年 | 541篇 |
1993年 | 502篇 |
1992年 | 534篇 |
1991年 | 504篇 |
1990年 | 484篇 |
1989年 | 451篇 |
1988年 | 410篇 |
1987年 | 348篇 |
1986年 | 359篇 |
1985年 | 378篇 |
1984年 | 399篇 |
1983年 | 393篇 |
1982年 | 397篇 |
1981年 | 353篇 |
1980年 | 288篇 |
1979年 | 311篇 |
1978年 | 249篇 |
1977年 | 229篇 |
1975年 | 200篇 |
1974年 | 214篇 |
1973年 | 239篇 |
1972年 | 226篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
721.
Marie E. Ferguson-Smith 《黑龙江环境通报》1991,11(8):661-670
The natural desire for couples to be parents and the medical practitioner's inability to treat most genetic diseases have been responsible for some of the most exciting research into infertility and genetic disorders. This has led in the United Kingdom to the establishment of the Warnock Committee of Inquiry into Human Fertilization and its report in 1984, and to a Review of the guidance on Research Use of Fetuses and Fetal Material published in 1989 and known as the Polkinghorne Report. The Warnock Report, among other ethical issues, considers the most fundamental question which has been debated for thousands of years, namely, What is life and when does it begin? More recently, the report has been responsible for new legislation which imposes ethical and legal restrictions on the scientific and medical community. The Polkinghorne Report recommends a voluntary code of practice which is morally and ethically acceptable within our society. We are also fortunate in the U.K. to have a parliamentary structure which allows debate on such important human issues and is prepared to impose ethical restrictions. 相似文献
722.
The index patient is a female fetus in which prenatal diagnosis of 8p trisomy was established after amniocentesis at 16 weeks of gestation. This fetus was the unbalanced product of a maternal translocation of 5q/8p (karyotype: 46,XX,t(5;8)(q35;pl 1). Internal malformations include an anomalous lobature of the right lung, a little and high atrio-ventricular communication, and an anomaly in the number and shape of the aortic semilunar valves. The possible relationship between the phenotype and the chromosomal abnormality is briefly discussed. 相似文献
723.
E. Stephanou 《Die Naturwissenschaften》1989,76(10):464-467
Dedicated to Prof. Dr. A. Buchs, University of Geneva, on the occasion of his 60th birthday. 相似文献
724.
This research was supported by a grant from the National Council for Research and Development, Israel, and the KFK, Karlsruhe, Germany. 相似文献
725.
726.
Dihydrorhodamine 123: a new flow cytometric indicator for respiratory burst activity in neutrophil granulocytes 总被引:13,自引:0,他引:13
This work was supported by DFG SFB 0207, project G 6. 相似文献
727.
We are very grateful to A. Gessner for his great help in the construction of the apparatus and A. Meyer for performance of some pressure bomb experiments. This work was supported by grants of the Deutsche Forschungsgemeinschaft (Forschergruppe Ökophysiologie) to U.Z. and O.L.L. 相似文献
728.
729.
730.