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61.
A new genetic polymorphism of an unidentified plasma protein (PLP1) in pigs was described by using a method of two-dimensional gel electrophoresis and protein staining. Two codominant alleles, with frequencies of 0.83 and 0.17, were found in the Swedish Yorkshire breed. The PLP1 marker was typed in a three-generation pedigree and tested for linkage against a set of 128 markers. The PLP1 locus showed significant LOD score values with three different microsatellite markers (S0092, DAGK and S005), previously assigned to chromosome 5. 相似文献
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A. A. Gontcharov 《Hydrobiologia》1996,336(1-3):93-97
A survey of the freshwater algal flora of the Primorsky Region, Russian Far East, is presented. During more than 70 years
of investigations 1659 species (including varieties and forms 2276 taxa) belonging to 346 genera of different groups of algae
have been recorded from this territory. The Primorsky Region is rich in habitats attractive to algae-rivers, lakes, reservoirs,
and ponds. The details of the distribution of algae in different types of waterbodies have been examined. The algal flora
of the region is comparable to the areas, and its taxonomical structure is typical for Eurasia. From this territory some new
species and varieties have been described — Achnanthes chankensis, Cymbella ventricosa var. hankensis, Surirella alisoviana, and others. The flora includes some rare species — Fragilaria magocsyi, Perone dimorpha, and Heterothrix monochloron, and some endemics of Asia — Navicula scutelloides var. baicalensis, N. globulifera var. nipponica, Gomphonema sphaerophorum, and Surirella tientsinensis. 相似文献
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N. H. Russel A. E. Hunter A. Haynes E. M. Bessell 《BMJ (Clinical research ed.)》1994,308(6945):1715-1716
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One of the major problems faced by conservation biologists is the allocation of scarce resources to an overwhelmingly large number of species in need of preservation efforts. Both demographic and genetic information have been brought to bear on this problem; however, the role of information obtained from genetic markers has largely been limited to the characterization of gene frequencies and patterns of diversity. While the genetic consequences of rarity may be a contributing factor to endangerment, it is widely recognized that demographic factors often may be more important. Because patterns of genetic marker variation are influenced by the same demographic factors of interest to the conservation biologist, it is possible to extract useful demographic information from genetic marker data. Such an approach may be productive for determining plant mating systems, inbreeding depression, effective population size, and metapopulation structure. In many cases, however, data consisting only of marker frequencies are inadequate for these purposes. Development of genealogical based analytical methods coupled with studies of DNA sequence variation within and among populations is likely to yield the most information on demographic processes from genetic marker data. Indeed, in some cases it may be the only means of obtaining information on the long-term demographic properties that may be most useful for determining the future prospects of a species of interest. 相似文献
69.
Analysis of 'homes' occupied by juvenile Octopus vulgaris shows flexible behaviour which may indicate specialized intelligence and tool use. Octopuses occupied sheltered areas for a short time, average 10 days, but stayed longer in larger homes and in areas where preferred prey was available. They did not simply respond to perceptual characteristics of a site, but instead chose locations potentially suitable and modified them by removing rocks and sand and bringing in items partially to block the aperture. 相似文献
70.