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Time and Complexity in Historical Ecology: Studies in the Neotropical Lowlands . William Baleé and Clark L. Erickson, eds. New York: Columbia University Press, 2006. 417 pp.  相似文献   
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Summary

Monthly samples of the shore crab Pachygrapsus transversus from two distinct annual periods showed that ovigerous females are present throughout the year in the population. However, the relative ovigerous abundance of specimens among sexually mature changes from less than 10% during the winter months to almost 80% in summer. Linear correlations for each year revealed that both temperature and photoperiod were positively associated with relative abundance of ovigerous females. Multiple regression analyses suggested that photoperiod was the main factor affecting breeding in this species. Timing of observed reproductive pattern may enhance larval survival because of particular oceanographic conditions in the study region and favor early juvenile development due to certain species-specific growth features.  相似文献   
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A new species of Daptonema is described based upon morphological characters and 18S rRNA sequence. Daptonema matrona sp. nov. was collected in Pina Basin (north‐eastern Brazil). It differs from all other species of the genus by the presence of reduced cephalic setae and straight spicules. These features require an adaptation of the generic diagnosis. Moreover, the females are characterized by intra‐uterine development of the offspring, considered herein as their major autapomorphic feature. Molecular systematic analyses supported Daptonema matrona sp. nov. as a distinct genetic and evolutionary lineage. The data also indicate hypotheses of taxonomic synonymies amongst some related taxa from Xyalidae as well as the paraphyly of Daptonema. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158 , 1–15.  相似文献   
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Current advances in genetic analysis are opening up our knowledge of the genetics of species differences, but challenges remain, particularly for out‐bred natural populations. We constructed a microsatellite‐based linkage map for two out‐bred lines of Drosophila montana derived from divergent populations by taking advantage of the Drosophila virilis genome and available cytological maps of both species. Although the placement of markers was quite consistent with cytological predictions, the map indicated large heterogeneity in recombination rates along chromosomes. We also performed a quantitative trait locus (QTL) analysis on a courtship song character (carrier frequency), which differs between populations and is subject to strong sexual selection. Linkage mapping yielded two significant QTLs, which explained 3% and 14% of the variation in carrier frequency, respectively. Interestingly, as in other recent studies of traits which can influence speciation, the strongest QTL mapped to a genomic region partly covered by an inversion polymorphism.  相似文献   
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In patrilocal groups, females preferentially move to join their mate’s paternal relatives. The gender‐biased gene flow generated by this cultural practice is expected to affect genetic diversity across human populations. Greater female than male migration is predicted to result in a larger decrease in between‐group differentiation for mitochondrial DNA (mtDNA) than for the non‐recombining part of the Y chromosome (NRY). We address the question of how patrilocality affects the distribution of genetic variation in human populations controlling for confounding factors such as ethno‐linguistic heterogeneity and geographic distance which possibly explain the contradictory results observed in previous studies. By combining genetic and bio‐demographic data from Lesotho and Spain, we show that preferential female migration over short distances appears to minimize the impact of a generally higher female migration rate in patrilocal communities, suggesting patrilocality might influence genetic variation only at short ranges.  相似文献   
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The recent expansion of Pentecostalism and independent churches in Africa has generated growing interest among social scientists. This attention parallels a renewed interest among Africanists on witchcraft and occult activities, also believed by many to be increasing. Some suggest the two trends may be related, but it remains unclear how and why. Drawing on a study of Pentecostalism and health in the city of Chimoio, Mozambique, in 2002–03 that focused on attitudes toward recent social change, we argue that structural adjustment economic reforms have deepened economic inequality and exacerbated household stresses that affect men and women differently. Women increasingly seek spiritual help for reproductive health problems from Pentecostal churches, whereas men disproportionately pay traditional healers to engage "occult" practices to manage misfortune related to employment. The increased resort to both spiritual resources reveals social distress caused by economic adjustment, with important implications for health programs.  相似文献   
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Here we described the development of the first set of Passiflora microsatellite loci isolated from an enriched genomic library. A sample of 43 individuals from 12 accessions of the yellow passion fruit was used to characterize those loci, which revealed up to 20 alleles per locus. Two loci were monomorphic. The observed (HO) and expected (HE) heterozygosities were very similar, as expected for a self‐incompatible species. Allelic diversity (HT) was 0.444. This set of markers will permit genetic structure analyses of cultivated and wild populations of Passiflora, and contribute for integrating genetic maps based on dominant markers, as they can provide bridge alleles.  相似文献   
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