全文获取类型
收费全文 | 10142篇 |
免费 | 451篇 |
国内免费 | 1379篇 |
专业分类
安全科学 | 588篇 |
废物处理 | 517篇 |
环保管理 | 1774篇 |
综合类 | 2977篇 |
基础理论 | 2114篇 |
环境理论 | 6篇 |
污染及防治 | 2652篇 |
评价与监测 | 698篇 |
社会与环境 | 464篇 |
灾害及防治 | 182篇 |
出版年
2023年 | 120篇 |
2022年 | 258篇 |
2021年 | 242篇 |
2020年 | 219篇 |
2019年 | 223篇 |
2018年 | 296篇 |
2017年 | 310篇 |
2016年 | 320篇 |
2015年 | 346篇 |
2014年 | 430篇 |
2013年 | 1070篇 |
2012年 | 570篇 |
2011年 | 671篇 |
2010年 | 556篇 |
2009年 | 567篇 |
2008年 | 621篇 |
2007年 | 578篇 |
2006年 | 509篇 |
2005年 | 391篇 |
2004年 | 379篇 |
2003年 | 404篇 |
2002年 | 319篇 |
2001年 | 273篇 |
2000年 | 245篇 |
1999年 | 196篇 |
1998年 | 167篇 |
1997年 | 136篇 |
1996年 | 144篇 |
1995年 | 136篇 |
1994年 | 102篇 |
1993年 | 102篇 |
1992年 | 123篇 |
1991年 | 64篇 |
1990年 | 80篇 |
1989年 | 60篇 |
1988年 | 41篇 |
1987年 | 50篇 |
1986年 | 52篇 |
1985年 | 55篇 |
1984年 | 58篇 |
1983年 | 58篇 |
1982年 | 44篇 |
1981年 | 63篇 |
1980年 | 51篇 |
1979年 | 28篇 |
1978年 | 28篇 |
1975年 | 22篇 |
1973年 | 20篇 |
1972年 | 19篇 |
1971年 | 18篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
111.
Aris Antsaklis John Politis Costas Karagiannopoulos Dionysios Kaskarelis Photini Karababa John Panourgias Marina Boussiou Dimitris Loukopoulos 《黑龙江环境通报》1984,4(4):289-296
Selective feticide is the procedure of choice when, in twin binovular pregnancy, only one of the fetuses is shown to be affected. As the probabilities for this condition are almost 1:2 when the genetic disease is due to homozygosity for two autosomal recessive genes, the problem is expected to occur frequently among the ever increasing number of couples seeking prenatal diagnosis of thalassaemia and the haemoglobinopathies. The present report is the first case of this condition and the ninth in the overall medical literature. 相似文献
112.
113.
114.
IntroductionTheprocessofmunicipalsolidwaste(MSW)isoneofthemostseriousissuesintermsofenvironmentalprotection.ProcessingofMSWwithoutfurtherdisastrouscontaminationcanbeachievedonlyinmodernizedmeasures,suchasincineratingandenergygeneratingconcurrently(Shen… 相似文献
115.
中国污染场地管理面临的问题及对策 总被引:20,自引:1,他引:20
概述了欧美国家污染场地管理现状,分析了中国污染场地管理面临的突出问题:中国在污染土壤管理的法律法规和标准、污染土壤的修复技术、污染土壤治理投入等方面同欧美国家有一定的差距.结合污染场地管理和场地风险评估、场地修复条件以及土地利用功能,提出了基于风险评估基础上污染场地管理程序和污染场地管理亟待开展的工作.指出了土壤环境标准体系,污染场地管理体系和污染场地修复技术体系的三元结构的完善是破解中国污染场地管理和修复的难题的根本. 相似文献
116.
Diana W. Bianchi MD Gretchen K. Zickwolf Melissa C. Yih Alan F. Flint Ossie H. Geifman Marlena S. Erikson John M. Williams 《黑龙江环境通报》1993,13(4):293-300
Fetal nucleated erythrocytes (NRBC) in maternal blood are a non-invasive source of fetal DNA for prenatal genetic screening. We compared the effectiveness of three monoclonal antibodies for the separation of fetal cells from maternal blood by flow sorting. Mononuclear blood cells from 49 healthy pregnant women were incubated with antibody to CD 71, CD 36, and/or glycophorin A (GPA), employed singly or in combination with each other. These monoclonal antibodies recognize surface antigens on haematopoietic precursor cells. Successful isolation of fetal cells was defined as detection of Y chromosomal sequences in maternal blood from women carrying male fetuses, with absence of Y sequences when female fetuses were carried. Thus, gender prediction accuracy was used as a measure of fetal cell separation. Using anti-CD 71 to isolate fetal cells, gender prediction was 57 per cent correct; with anti-CD 36, it was 88 per cent correct. Anti-GPA, an erythrocyte-specific antigen, used alone or in combination with anti-CD 71 or 36, improved gender prediction to 100 per cent. We conclude that antibody to GPA improves the retrieval of fetal NRBC from maternal blood, permitting genetic analysis by the polymerase chain reaction. 相似文献
117.
Data from 2907 transcervical CVS cases performed on singleton pregnancies were reviewed retrospectively and villus sample size was correlated with cytogenetic results, placental location, maternal age at the expected date of confinement (EDC), gestational age at the time of sampling, birth weight, gestational age at the time of delivery, and pregnancy outcome. No correlation was noted between villus sample size and maternal age, gestational age at sampling, gestational age at delivery, birth weight, or pregnancy outcome. An inverse correlation between villus sample size and percentage of abnormal cytogenetic findings was statistically significant (X2 = 8·53, p <0·01). The percentage of small samples was greater when the placenta was anterior, lateral, or fundal than when the placenta was posterior. 相似文献
118.
119.
乐果对金鱼的急性毒性影响 总被引:2,自引:0,他引:2
用改进的寇氏法(karber)测定了乐果对金鱼(Carassius auratus)的急性毒性。急性试验经150mg/L、188.4mg/L、234.4mg/L、291.7mg/L、360mg/L乐果暴露4d,在15%~20%下,24、48、72、96h的L11m值分别为297.17、289.13、259.12、238.67mg/L,其95%置信限分别为284.25~310.67、275.17~303.81、243.33~275.93、223.98~254.33mg/L。 相似文献
120.
CharacteristicsofphosphoruschemistryanditsgeographicaldistributionintheHaiheRivervalley,NorthChinaJiangGaoming;HuangYinxiao;L... 相似文献