全文获取类型
收费全文 | 4112篇 |
免费 | 43篇 |
国内免费 | 28篇 |
专业分类
安全科学 | 88篇 |
废物处理 | 273篇 |
环保管理 | 308篇 |
综合类 | 461篇 |
基础理论 | 838篇 |
环境理论 | 6篇 |
污染及防治 | 1513篇 |
评价与监测 | 399篇 |
社会与环境 | 275篇 |
灾害及防治 | 22篇 |
出版年
2023年 | 50篇 |
2022年 | 125篇 |
2021年 | 168篇 |
2020年 | 72篇 |
2019年 | 80篇 |
2018年 | 150篇 |
2017年 | 156篇 |
2016年 | 225篇 |
2015年 | 116篇 |
2014年 | 235篇 |
2013年 | 393篇 |
2012年 | 295篇 |
2011年 | 312篇 |
2010年 | 231篇 |
2009年 | 167篇 |
2008年 | 228篇 |
2007年 | 257篇 |
2006年 | 181篇 |
2005年 | 152篇 |
2004年 | 115篇 |
2003年 | 88篇 |
2002年 | 91篇 |
2001年 | 54篇 |
2000年 | 50篇 |
1999年 | 28篇 |
1998年 | 18篇 |
1997年 | 13篇 |
1996年 | 10篇 |
1995年 | 18篇 |
1994年 | 9篇 |
1993年 | 5篇 |
1992年 | 8篇 |
1991年 | 4篇 |
1990年 | 7篇 |
1988年 | 2篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1980年 | 2篇 |
1978年 | 2篇 |
1970年 | 2篇 |
1967年 | 5篇 |
1966年 | 4篇 |
1965年 | 2篇 |
1964年 | 5篇 |
1962年 | 3篇 |
1959年 | 4篇 |
1958年 | 16篇 |
1957年 | 5篇 |
1956年 | 2篇 |
1955年 | 2篇 |
排序方式: 共有4183条查询结果,搜索用时 15 毫秒
931.
Juan José Soler Manuel Soler Anders Pape Møller Juan Gabriel Martínez 《Behavioral ecology and sociobiology》1995,36(3):201-206
When brood parasites are about to lay an egg, they have to decide which nest to parasitize. The best nest in which to lay will depend on the parenting ability of the host. We have studied selection of magpie (Pica pica) hosts by great spotted cuckoos (Clamator glandarius). Great spotted cuckoos preferentially parasitize large host nests. Nest volume in magpies is a good indicator of territory quality, since there is a negative relationship between magpie nest size and breeding date, and timing of breeding in magpies is known to be positively related to territory quality. Moreover, magpies occupying high-quality territories have high breeding success. Therefore, nest size is positively related to the quality of magpies. Parasitized magpie nests were of greater volume than the nearest neighbouring nest not parasitized by the great spotted cuckoo. In order to test whether the great spotted cuckoos might select high-quality magpie hosts, we manipulated pairs of parasitized and non-parasitized nests with identical laying dates and habitats, introducing into each of the nests the same number of parasitic and non-parasitic eggs. The number of fledglings reared (magpie plus great spotted cuckoo chicks) in naturally parasitized nests was higher than in experimentally parasitized nests. Thus, the probability of survival of the parasite chicks increased if cuckoo eggs were laid in the nests of high-quality hosts originally chosen by the parasite. 相似文献
932.
Lerchl A 《Die Naturwissenschaften》2004,91(9):422-425
The effects of month of birth (MOB) on life expectancy of a German subpopulation was investigated. Data from people who died in North Rhine Westphalia in the years 1984 (n=188,515) and 1999 (n=188,850) were analyzed. For comparative purposes, all deaths that occurred at an age of <50 years were excluded (1984: 8.4%; 1999: 6.2%). In general, individuals born in May through July had the lowest age at death (1984: 75.27±0.09 years; 1999: 77.58±0.09 years), while those born between October and December had the highest (1984: 75.98±0.08 years; 1999: 78.35±0.09 years), supporting earlier findings. The observed amplitudes (differences between highest and lowest values) were more pronounced in men than in women. When comparing these data of MOB effects on life expectancy with earlier findings in Australia, Austria, Denmark, Ukraine, and the USA, it is evident that a negative correlation exists between the average age at death and the MOB amplitudes. Separate analyses by gender, possible for the data from Germany, the Ukraine, and the USA, revealed a significant negative correlation for men, but not for women. A new hypothesis is therefore presented describing an influence of life quality, as reflected by average life expectancy, on the extent of MOB effects; for example, seasonally variable sensitivities during pregnancy/early childhood. 相似文献
933.
Apesteguía S 《Die Naturwissenschaften》2004,91(10):493-497
Ornithischian and theropod dinosaurs were morphologically diverse during the Cretaceous. In contrast, sauropods were relatively more conservative. The anatomy of Bonitasaura salgadoi, a new 9-m titanosaurian sauropod from Upper Cretaceous beds of Patagonia, suggests that sauropod anatomical diversity would have included unexpected items. Its unusual, rectangular lower jaw possesses narrow, anteriorly restricted teeth and shows evidence of a sharp keratinous sheath over the non-dentigerous region that probably worked to guillotine plant material. This discovery definitely demonstrates that titanosaurs acquired a mandibular configuration similar to that of some basal diplodocoids, as had already been suggested by the lower jaw of the controversial genus Antarctosaurus. This oral configuration, plus the beak-like structure and the skull shape, resemble some traits more commonly seen in Laurasian ornithischians, mostly unexpressed in southern continents. A high sauropod morphological diversity seems to be in agreement with the poorly represented ornithischian clades of the southern hemisphere.Communicated by G. Mayr 相似文献
934.
935.
Miagostovich Marize Pereira Rocha Mônica Simões dos Reis Fabiane Bertoni Sampaio Marcelo Santos de Saldanha da Gama Gracie Carrijo Renata Malta Fabio Correia Rodrigues Janaína Genuino Amanda Ribeiro da Silva Assis Matheus Fumian Tulio Machado Barrocas Paulo Rubens Guimarães 《Food and environmental virology》2020,12(2):130-136
Food and Environmental Virology - The availability of drinking water is one of the main determinants of quality of life, disease prevention and the promotion of health. Viruses are important agents... 相似文献
936.
Fermín C. Iturriza 《Die Naturwissenschaften》1967,54(21):565-565
937.
938.
939.
Juliano Gonçalves Pereira Vanessa Mendonça Soares Fernanda Gil de Souza Leonardo Ereno Tadielo Emanoelli Aparecida Rodrigues dos Santos Mário Celso Sperotto Brum Andreia Henzel Eduarda Hallal Duval Fernando Rosado Spilki Wladimir Padilha da Silva 《Food and environmental virology》2018,10(4):365-372
The aim of this study was to investigate hepatitis A virus (HAV), hepatitis E (HEV), and rotavirus (RV) in fresh and processed meat traded on the border of Brazil with Argentina and Uruguay. In total, 159 samples of raw and processed foods of animal origin were collected in Paso de los Libres, Argentina (n?=?53 raw meat, n?=?24 processed meat) and Rivera, Uruguay (n?=?55 raw meat, n?=?18 processed meat), or were seized by the Brazilian International Agricultural Surveillance System—VIGIAGRO (Brazil–Argentina border) (n?=?8 raw meat, n?=?1 bush meat). All samples were tested for the presence of HAV, HEV, and RV genomes. HAV genes were detected in 18.23% of samples and RV genes in 23.89%. No HEV-positive samples were detected. HAV was also detected in two of the VIGIAGRO samples. Processed meats from Argentina and Uruguay had a higher rate of HAV and RV than raw meat (P?>?0.05). The median HAV in the Argentinian and Uruguayan samples was 6.9?×?104 and 3.5?×?103 copies/g, respectively. The presence of RV viral genes in raw meats from Argentina was significant, and this was not observed in processed meats. The presence of HAV and RV genes in a significant portion of products from Argentina and Uruguay is a potential source of human infection. This also indicates precarious conditions of acquisition, processing, and manipulation, which could be improved by improved regulation of food across borders. 相似文献
940.
Adrian A. Farías Laura N. Mojsiejczuk María B. Pisano Fernando S. Flores Juan J. Aguilar Ana N. Jean Laura A. Yanes Gisela Masachessi Veronica E. Prez María B. Isa Rodolfo H. Campos Viviana E. Ré Silvia V. Nates 《Food and environmental virology》2018,10(1):121-126
Environmental surveillance is an effective approach to investigate the circulation of human enteroviruses in the population. Enteroviruses E14, CVA9, E-6, E16, E20, E25, E13, and CVA24 were detected in sewage and a watercourse in central Argentina. E14 was the most frequent serotype and was found for the first time in environmental samples in our region. Phylogenetic and coalescence analyses showed at least two recent introduction events. 相似文献