首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1389篇
  免费   8篇
  国内免费   1篇
安全科学   25篇
废物处理   19篇
环保管理   128篇
综合类   1004篇
基础理论   93篇
污染及防治   100篇
评价与监测   20篇
社会与环境   6篇
灾害及防治   3篇
  2016年   10篇
  2013年   55篇
  2012年   11篇
  2011年   15篇
  2010年   18篇
  2009年   8篇
  2008年   19篇
  2007年   15篇
  2006年   10篇
  2005年   10篇
  2004年   9篇
  2003年   20篇
  2002年   10篇
  1998年   12篇
  1995年   59篇
  1994年   51篇
  1993年   42篇
  1992年   37篇
  1991年   26篇
  1990年   33篇
  1989年   28篇
  1988年   34篇
  1987年   29篇
  1986年   21篇
  1985年   16篇
  1984年   14篇
  1983年   19篇
  1982年   13篇
  1981年   8篇
  1976年   9篇
  1975年   10篇
  1973年   11篇
  1965年   8篇
  1962年   9篇
  1961年   8篇
  1959年   9篇
  1957年   13篇
  1955年   8篇
  1940年   10篇
  1939年   10篇
  1937年   9篇
  1935年   11篇
  1934年   7篇
  1919年   47篇
  1918年   44篇
  1917年   36篇
  1916年   53篇
  1915年   37篇
  1914年   71篇
  1913年   106篇
排序方式: 共有1398条查询结果,搜索用时 15 毫秒
591.
592.
593.
594.
Book reviews     
ENGLISH STRUCTURE PLANNING

Eds: D. T. Cross and M. R. Bristow

Pion Ltd., London, 1983. £16.00.

AN INTRODUCTION TO URBAN RENEWAL

Michael S. Gibson and Michael J. Longstaff

London: Hutchinson, 1982. 384 pp.

INTEGRATED URBAN MODELS

S. H. Putman

Pion Ltd., 1983, 332 pp.

EXPLANATION PREDICTION AND PLANNING: THE LOWRY MODEL

M. T. Webber

Pion Ltd., London, 1984, 214 pp.

THE GOVERNMENT AND ADMINISTRATION OF METROPOLITAN AREAS IN WESTERN DEMOCRACIES

Alan Norton

Institute of Local Government Studies, University of Birmingham, 1983, 57 pp.

THE MANAGEMENT OF SEMI‐NATURAL WOODLAND

County Planning Officers’ Society (available from Hampshire County Planning Dept., price £2.00).  相似文献   

595.
596.
597.
Charcot-Marie-Tooth disease type 1A (CMT1A) is a frequent hereditary motor and sensory neuropathy of the peripheral nerves. In most cases, the disease is associated with a 1.5 Mb tandem duplication at 17p11.2. A 42-year-old pregnant woman requested prenatal diagnosis because of her age and since both her husband and two children were severely affected with CMT1. The CMT1A duplication was demonstrated in the father's, the two children's, and the fetus's DNA using different molecular genetic methods. Although cytogenetical analysis showed a normal female karyotype in the fetus, the parents decided to terminate the pregnancy because of the genetic risk associated with the CMT1A duplication.  相似文献   
598.
In order to verify whether fetal and maternal adrenal gland suppression induces effects on fetal behaviour, triamcinolone was administered to five healthy pregnant women at 35 weeks of gestation. Five patients of the same gestational age were used as control. Fetal heart rate (FHR) and fetal movements were recorded continuously over 2-h interval by means of cardiotocography. After 3 weeks (38 weeks of gestation) the recordings were repeated without drug administration. Cortisol, adrenocorticotropin hormone, 17 β-estradiol and unconjugated estriol were measured at the same time every 2 h in maternal peripheral plasma. At 35 weeks we found a loss of circadian rhythms of the hormones investigated and modifications of ultradian and circadian patterns of FHR in the treated group with respect to the control. No differences in hormonal and biophysical parameters were found between the two groups after the end of treatment (38 weeks). These data suggest that the inhibition of fetal and maternal adrenal glands could cause modifications of FHR patterns.  相似文献   
599.
A quantitative method for cholinesterases in amniotic fluid using the non-specific substrate α naphthyl acetate and the cholinesterase-specific inhibitor, eserine, is described. This assay was used to test 671 samples of amniotic fluid. The diagnoses for fetal ONTDs, based on the levels of AChE + ChE, were compared with those made for the same samples by the AFP method. Correct diagnoses were made by both methods with amniotic fluid from 35 women carrying fetuses with ONTDs and 631 carrying normal fetuses. There were five false-positive test results for normal fetuses by both methods when the cut-off points were 5 standard deviations above the mean for AFP and above the upper limit of the normal range (7. 5 milliunits) for cholinesterase (AChE + ChE). None of the false-positive samples from either method had the acetylcholinesterase band of activity characteristic of ONTDs after gel electrophoresis. In addition to the above 671 samples, 37 pregnancies with serious fetal abnormalities other than ONTDs were tested. Two were identified by both the AFP and AChE + ChE methods, two more by AFP assay and one other by the AChE + ChE assay.  相似文献   
600.
After a lapse of almost two decades, US energy and mining companies are once again involving themselves with worker housing. Reinvolvement began in the 1970s. It is in response to a recognition of the fiscal consequences of project delays and an industry responsibility to both workers and project area communities. It differs from the heavy reliance on company towns which were prevalent in the US during the 19th and early 20th Centuries. Industry involvement now relies not only on supply, but on stimulation. A greater variety of housing initiatives is being utilised and a company must carefully select the housing initiative best suited to its circumstances. These initiatives need to be guided by the following set of decision guidelines: (1) housing function; (2) housing user; (3) housing type and quantity needs; (4) monetary expectations; (5) role of the industry; (6) housing unit location; (7) responsibilities after housing is completed; and (8) amenities and community sharing. Then, housing involvement must be reviewed in light of past and present industry experiences. Innovative ideas need to be evaluated with respect to proven initiatives, as well as their presumed goal and potential for success.Study performed under Contract No. DE-AC02-76CH00016 with the U.S. Department of Energy  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号