全文获取类型
收费全文 | 2637篇 |
免费 | 30篇 |
国内免费 | 18篇 |
专业分类
安全科学 | 68篇 |
废物处理 | 82篇 |
环保管理 | 427篇 |
综合类 | 567篇 |
基础理论 | 575篇 |
环境理论 | 4篇 |
污染及防治 | 661篇 |
评价与监测 | 181篇 |
社会与环境 | 108篇 |
灾害及防治 | 12篇 |
出版年
2023年 | 19篇 |
2022年 | 23篇 |
2021年 | 30篇 |
2020年 | 31篇 |
2019年 | 27篇 |
2018年 | 55篇 |
2017年 | 56篇 |
2016年 | 58篇 |
2015年 | 59篇 |
2014年 | 70篇 |
2013年 | 195篇 |
2012年 | 95篇 |
2011年 | 139篇 |
2010年 | 100篇 |
2009年 | 114篇 |
2008年 | 127篇 |
2007年 | 147篇 |
2006年 | 101篇 |
2005年 | 93篇 |
2004年 | 106篇 |
2003年 | 84篇 |
2002年 | 99篇 |
2001年 | 44篇 |
2000年 | 38篇 |
1999年 | 36篇 |
1998年 | 27篇 |
1997年 | 33篇 |
1996年 | 33篇 |
1995年 | 35篇 |
1994年 | 50篇 |
1993年 | 20篇 |
1992年 | 21篇 |
1991年 | 22篇 |
1990年 | 20篇 |
1989年 | 15篇 |
1988年 | 23篇 |
1987年 | 16篇 |
1986年 | 20篇 |
1984年 | 13篇 |
1983年 | 16篇 |
1982年 | 17篇 |
1981年 | 17篇 |
1980年 | 16篇 |
1979年 | 17篇 |
1978年 | 14篇 |
1977年 | 12篇 |
1960年 | 11篇 |
1959年 | 12篇 |
1956年 | 12篇 |
1954年 | 17篇 |
排序方式: 共有2685条查询结果,搜索用时 15 毫秒
951.
Martin J. Steinbauer Fredrik Östrand Tom E. Bellas Anna Nilson Fredrik Andersson Erik Hedenström Michael J. Lacey P. Florian Schiestl 《Chemoecology》2004,14(3-4):217-223
Summary. The autumn gum moth, Mnesampela privata
(Guenée) (Lepidoptera: Geometridae), is native to Australia
and can be a pest of plantation eucalypts. Field-collected
and laboratory-reared female autumn gum moths were
dissected to remove glands likely to contain components of
the sex pheromone. Using gas chromatography (GC) and
combined gas chromatography–mass spectrometry (GC-MS),
three compounds were identified from female extracts,
namely (3Z,6
Z,9
Z)-3,6,9-nonadecatriene, 1-hexadecanol
and 1-octadecanol (confirmed by comparison with synthetic
samples). Nonadecatriene elicited an antennal response in
male autumn gum moth during gas chromatographic
analyses combined with electroantennographic detection
(GC-EAD). In electroantennogram (EAG) recording male
M. privata antennae responded to the nonadecatriene. Nonadecatriene was synthesised via Kolbe electrolysis,
starting with (9Z,12Z,15Z)-octadeca-9,12,15-trienoic acid
(linolenic acid) and propanoic acid or via an alternative
four-step method also starting from linolenic acid. In field
trials (3Z,6Z,9Z)-3,6,9-nonadecatriene proved attractive
to male moths. Thus, we conclude that (3Z,6Z,9Z)-3,6,9-
nonadecatriene is a sex pheromone component of autumn
gum moth. This component has been identified in extracts
from other geometrids in the same subfamily, Ennominae.
However, to our knowledge this is the first example where
(3Z,6Z,9Z)-3,6,9-nonadecatriene has been found in females
and also proved attractive to male moths when presented on its
own. Our results are discussed in relation to other geometrid
pheromones. 相似文献
952.
953.
People suffering from various symptoms while in air-conditioned rooms often show sensitizations to fungi that can be isolated when the fungi are dremoved from air conditioners. By using specific challenge tests it was shown that fungal spores in air conditioners can evoke allergic symptoms. Hyposensitization was the specific therapy prescribed for such allergic reactions. After hyposensitization therapy, more than 70% of the patients so treated could live and work again in air-conditioned rooms without developing specific symptoms. 相似文献
954.
955.
In Zimbabwe, veterinary fences are used to control trypanosomiasis and foot- and-mouth disease, two important diseases that threaten cattle production and beef exports. Wildlife is implicated in both instances and the effects of fences on wildlife conservation and land use are discussed in relation to these two diseases. Advantages and disadvantages related to direct and indirect fence effects are outlined. Although the maintenance of fences for trypanosomiasis control is likely to become obsolete, control of foot- and-mouth disease will rely on fences for the foreseeable future. Most of Zimbabwe's protected wildlife areas are located in marginal agricultural land around the periphery of the country where cattle productivity is low. This land should be excluded from any involvement in the beef export industry rather than attempting its inclusion through cordoning and isolating individual protected areas. Within such land, the need for rigid veterinary restrictions should then disappear and allow more flexible strategies for disease control, including adaptive and imaginative approaches to land-use planning. 相似文献
956.
Martin Kavaliers Melissa A. Fudge Douglas D. Colwell Elena Choleris 《Behavioral ecology and sociobiology》2003,54(5):423-430
The detection and avoidance of parasitized males is a component of female mate choice. Here we show that female mice can distinguish between the odors of individual males infected with an ectoparasite, the murine louse, Polyplax serrata, and uninfected males. Female mice displayed aversive responses to, and avoided the odors of, parasitized males. A 15 min exposure to the urinary odors of infected males induced an endogenous opioid-peptide-mediated reduction in pain sensitivity or analgesia, while a brief 1 min exposure to the odors elicited a non-opioid-mediated analgesic response. These neuromodulatory mechanisms facilitate the expression of a variety of anxiety and stress associated responses of which pain inhibition is one component. Females further distinguished between novel and familiar infected males. Prior exposure to the odors of an infected males reduced the degree of analgesia expressed and the associated levels of anxiety and stress and their concomitant costs. In a Y-maze odor preference test females also displayed a marked overall preference for, and initial choice of, the odors of clean, uninfected males and an active discrimination against, and avoidance of, the odors of both familiar and novel infected males. These findings indicate that female mice can distinguish between males infected with an ectoparasite and clean uninfected males and display aversive and avoidance responses to infected males. They also show that females can discriminate between individual infected males and modulate their aversive responses to the odors of infected males on the basis of prior familiarity. This is likely part of the mechanisms whereby females can both reduce the transmission of ectoparasites, such as lice, to themselves and select for parasite-free males. 相似文献
957.
958.
959.
Parts II – IV will be published in the following issues of ESPR. 相似文献
960.