全文获取类型
收费全文 | 13590篇 |
免费 | 182篇 |
国内免费 | 127篇 |
专业分类
安全科学 | 485篇 |
废物处理 | 582篇 |
环保管理 | 2236篇 |
综合类 | 1527篇 |
基础理论 | 3590篇 |
环境理论 | 9篇 |
污染及防治 | 3646篇 |
评价与监测 | 941篇 |
社会与环境 | 802篇 |
灾害及防治 | 81篇 |
出版年
2022年 | 127篇 |
2021年 | 104篇 |
2020年 | 91篇 |
2019年 | 108篇 |
2018年 | 195篇 |
2017年 | 210篇 |
2016年 | 315篇 |
2015年 | 239篇 |
2014年 | 313篇 |
2013年 | 1198篇 |
2012年 | 424篇 |
2011年 | 620篇 |
2010年 | 486篇 |
2009年 | 529篇 |
2008年 | 640篇 |
2007年 | 679篇 |
2006年 | 580篇 |
2005年 | 487篇 |
2004年 | 452篇 |
2003年 | 511篇 |
2002年 | 435篇 |
2001年 | 570篇 |
2000年 | 411篇 |
1999年 | 250篇 |
1998年 | 198篇 |
1997年 | 186篇 |
1996年 | 205篇 |
1995年 | 221篇 |
1994年 | 195篇 |
1993年 | 159篇 |
1992年 | 175篇 |
1991年 | 162篇 |
1990年 | 172篇 |
1989年 | 162篇 |
1988年 | 138篇 |
1987年 | 121篇 |
1986年 | 102篇 |
1985年 | 129篇 |
1984年 | 122篇 |
1983年 | 128篇 |
1982年 | 131篇 |
1981年 | 122篇 |
1980年 | 91篇 |
1979年 | 96篇 |
1978年 | 73篇 |
1977年 | 83篇 |
1976年 | 68篇 |
1975年 | 64篇 |
1974年 | 65篇 |
1973年 | 58篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
111.
Gulzar Kassam Andrew T. L. Chen Marshall F. Goldberg Suzanne Trusler Godfrey P. Oakley Jr. 《黑龙江环境通报》1984,4(3):213-216
Although prenatal genetic diagnosis can usually provide prospective parents with information as to whether their fetus is affected with certain genetic conditions, the presence of twins and the uncertainty about the phenotype of some chromosome variations pose a major dilemma and make genetic counselling very difficult. Here, a case report of an unusual chromosome aberration (pericentric inversion of chromosome no. 17) in a twin pregnancy which was originally suspected to be monoamniotic but later proved to have two sacs was presented. 相似文献
112.
E. A. Loupian A. A. Mazurov E. V. Flitman D. V. Ershov G. N. Korovin V. P. Novik N. A. Abushenko D. A. Altyntsev V. V. Koshelev S. A. Tashchilin A. V. Tatarnikov I. Csiszar A. I. Sukhinin E. I. Ponomarev S. V. Afonin V. V. Belov G. G. Matvienko T. Loboda 《Mitigation and Adaptation Strategies for Global Change》2006,11(1):113-145
113.
Defense Mechanisms of Arthropods, no. 96; no. 95: Eisner et al.: Chemoecology (in press) 相似文献
114.
Mary C. Phelan Ph.D. Robert A. Saul Thompson A. Gailey Jr Steven A. Skinner 《黑龙江环境通报》1995,15(3):274-277
Mosaicism for the Wolf-Hirschhorn syndrome, del(4)(p16), is extremely rare and has not been reported in association with a numerical chromosome abnormality. We report the prenatal diagnosis of mosaic del(4)(p16) and non-mosaic trisomy 21 in a 16-week female fetus. The pregnancy ended in spontaneous abortion at 34 weeks secondary to fetal demise. The fetus had features of both 4p – and trisomy 21. 相似文献
115.
M. Peter Marinkovich MD Guerrino Meneguzzi Robert E. Burgeson Claudine Blanchet-Bardon Karen A. Holbrook Lynne T. Smith Angela M. Christiano Jean-Paul Ortonne 《黑龙江环境通报》1995,15(11):1027-1034
Herlitz junctional epidermolysis bullosa (HJEB) is a severe blistering disorder which usually results in death during infancy. We have previously shown that the anchoring filament protein laminin-5 (kalinin/nicein), which mediates keratinocyte attachment and dermal–epidermal cohesion, is abnormally expressed in individuals with HJEB. Laminin-5 was detected by Western blot analysis in amniotic fluid from 44 consecutive normal secondtrimester control pregnancies, but was undetectable in second-trimester amniotic fluid from four pregnancies with fetuses affected by HJEB. In one case of severe non-Herlitz JEB, laminin-5 was detected in both amniotic fluid and skin. In human amniotic fluid, the laminin-5 a3 subunit was processed to a major 165 kD species and a minor 145 kD species and the β2 subunit was partially processed to 105 kD. Although laminin-5 was covalently associated with laminin-6 (K-laminin) in amniotic membrane, no covalent interaction was detected in amniotic fluid. Laminin-5 from amniotic fluid strongly supported keratinocyte attachment. These results suggest that Western blot analysis of second-trimester amniotic fluid is useful in determining the prenatal diagnosis of HJEB and that laminin-5 may serve a physiologically important function in amniotic fluid. 相似文献
116.
Stickler syndrome is an autosomal dominant disorder of the connective tissue which includes ocular and systemic manifestations. We report on a large kindred in which we were able to demonstrate very tight linkage between the disease and the type II collagen gene (COL2A1) (LOD score 3·91 at θ=0). In a family in which the father and one of his daughters were severely affected, DNA analysis from a chorionic villus sample demonstrated that the fetus possessed the normal allele of COL2A1. Thereafter a normal child was born. 相似文献
117.
The prenatal diagnosis of The Turner Syndrome is described at a menstrual age of 12 weeks. Detection of cystic hygroma was followed by vaginal chorionic villous sampling (CVS) which revealed a 45,X karyotype. Early documentation of fetal karyotype in the presence of a cystic hygroma is essential for accurate diagnosis and genetic counselling. 相似文献
118.
Plasticity of honeybee castes 总被引:1,自引:0,他引:1
119.
Dr Claire Julian-Reynier Genevieve Macquart-Moulin Jean-Paul Moatti Anderson Loundou Yvette Aurran Françoise Chabal Ségolene Aymé 《黑龙江环境通报》1993,13(7):613-627
The objective of this study was to explore women's attitudes towards prenatal diagnosis of trisomy 21 and to examine some of the factors possibly responsible for these attitudes before implementing in real practice serological screening of pregnant women at risk for trisomy 21. We carried out a telephone survey on a representative sample of women who had recently had a normal livebirth delivery in the Marseille district in 1990. The participation rate was 80 per cent and the average age of the mothers was 28-9 years. Among the 514 women interviewed, 78 per cent stated that they would ask for an amniocentesis for a 1 per cent risk of trisomy 21 at their next pregnancy. When adjusting for confounding factors, the decision to have or not to have an amniocentesis was found to depend not only on the women's attitude towards induced abortion, but also on their understanding of the risk involved and on the social context (knowing a handicapped child, discussion with the father). It also depended on the women's age and on what they knew about amniocentesis from the medical point of view. The risk of miscarriage can influence a woman's choice but this objection was not found to affect the women's decisions significantly in our survey. The data showed the existence of a high potential demand for fetal karyotyping. 相似文献
120.
Cynthia J. Sims MD Don T. Fujito Dennis R. Burholt Josef Dadok Harlan R. Giles D. Allan Wilkinson 《黑龙江环境通报》1993,13(6):473-480
We have investigated the ability of high-resolution proton NMR spectroscopy to provide a biochemical constituent screening of human amniotic fluid (AF). Proton NMR spectra were obtained at 300 MHz on AF from patients undergoing amniocentesis in the mid-trimester. Only AF from normal pregnancies (normal fetal karyotype, normal a-fetoprotein levels, normal birth outcome) was used in this study. The AF supernatant was lyophilized and resuspended in deuterated water containing 0.1 mm phosphate buffer and 6.02 mm disodium maleate. Identification of low molecular weight compounds was confirmed by two-dimensional NMR spectra (primarily correlated spectroscopy, or COSY) and standard addition techniques. A broad profile of compounds were ‘NMR visible’ in a single proton spectrum, including creatinine, glucose, organic acids (acetate, citrate, and lactate) and several amino acids (alanine, histidine, leucine, phenylalanine, tyrosine and valine). The proton spectrum was unaffected by prior freezing/thawing of AF samples. We were able to quantify compounds by comparison with an added concentration standard (maleate) at concentrations as low as 30 μm. Good agreement with literature values based on other analytical techniques was obtained. 相似文献