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51.
Communicating individual identity is essential for stable social systems. It is assumed that there are benefits for both senders
and receivers to provide and discriminate identity cues. In this study, we investigate the possible routes senders use to
acoustically broadcast their individual identity. Using discriminant function analysis of temporal and spectral acoustic measurements
and analysis of song-element order, we explore the means male rock hyrax (Procavia capensis) singers utilize vocalization to express individual identity. Despite the fact that males use only three song elements, the
pattern of acoustic characteristics, their temporal and frequency attributes vary according to the identity of singer. We
show that in hyrax, individuality is expressed by highly variable, complex signals that are not condition dependent and are
stable over years in singers that did not alter their spatial position. We also show that individuality signals are not linked
to relatedness or to geographic location. The ability to discriminate individuals from vocal signatures needs to be further
tested using controlled playback experiments. 相似文献
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Molecular Genetics of Pre-1940 Red Wolves 总被引:5,自引:0,他引:5
Conservation of the endangered red wolf (Canis rufus) has become a controversial issue because its genetic and morphological composition has been altered by hybridization with coyotes (C. latrans) and possibly gray wolves (C. lupus) making its evolutionary origins difficult to ascertain. The evolutionary hypothesis based on morphological data is that the red wolf had an Early Pleistocene origin and was the predecessor of both modern coyotes and gray wolves. After 1940 red wolves hybridized with coyotes as the species vanished from the wild. In contrast to this ancient origin-recent introgression hypothesis, molecular data are more consistent with an origin through hybridization between gray wolves and coyotes. Interspecific hybridization may have occurred repeatedly over time prior to European settlement in the southcentral United States or may have been induced recently by anthropogenic changes. We review recent molecular evidence and present new results from the analysis of mitochondrial and nuclear DNA markers in pre-1940 populations of red wolves. Our results are inconsistent with an ancient origin of the red wolf and support the hybridization model. We discuss possible hybridization scenarios and reasons for the red wolf reintroduction program to be concerned with the effects of genetic introgression from coyotes. 相似文献
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Maxim Rubin-Blum Rami Tsadok Eli Shemesh Beverly N. Goodman-Tchernov James A. Austin Jr. Dwight F. Coleman Zvi Ben-Avraham David F. Gruber Dan Tchernov 《Marine Biology》2014,161(6):1229-1239
During the 2010/2011 Exploration vessel Nautilus expedition to the Mediterranean Sea, samples of Lamellibrachia (Siboglinidae, Annelida) were imaged in situ and collected from hydrothermal vent and methane “cold seeps.” An analysis of these Lamellibrachia and their endosymbiotic thioautotrophic gammaproteobacteria reveals two distinct endosymbiont phylotypes. Phylotype 1 was present in Lamellibrachia specimens from 947 m at the Eratosthenes seamount seep (a seep off Cyprus in the Eastern Mediterranean), and Phylotype 2 was found in siboglinids from 618 m at a hydrothermal vent within Palinuro volcanic complex in Tyrrhenian Sea. Both phylotypes coexist in siboglinids at 1,036 m from the Palmachim disturbance, a cold seep in the Eastern Mediterranean’s Levantine basin. Our results, combined with existing knowledge of siboglinid host and endosymbiotic bacteria biogeography, reveal that two major groups of endosymbionts coexist within lamellibranchids and escarpids. The phylogenetic clustering of these bacteria is primarily influenced by geographic location, rather than selection by the siboglinid host. 相似文献
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We report an unusual case of the complete Currarino triad diagnosed in a fetus at 21 weeks' gestation by means of prenatal ultrasonography (US). The highly suspicious findings in the fetus were accompanied by analogous US findings in the mother who suffered from mild symptoms of up to that time unrecognized Currarino triad. Consecutively, magnetic resonance imaging (MRI) confirmed the findings simultaneously in the fetus and in her mother. This is the first report describing the prenatal diagnosis of Currarino triad without the background of positive family history. To our knowledge, the prenatal MRI findings of Currarino triad have not yet been published. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献