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991.
Hovey EO 《Science (New York, N.Y.)》1905,22(559):333-336
992.
O. Schmidt D. Dujesiefken H. Stobbe U. Moreth R. Kehr Th. Schröder 《Forest Pathology》2008,38(2):124-128
Bacteria were isolated from necrotic lesions on a horse chestnut tree (Aesculus hippocastanum) with bleeding canker in Hamburg, Germany. Sequencing of the rDNA-ITS region revealed great similarity to pathovars of Pseudomonas syringae. Pseudomonas syringae pv. aesculi was identified by sequence homology of the gyrase B gene. This is the first report of P. syringae pv. aesculi in Germany. Phytophthora was not detected. 相似文献
993.
Stallion fertility has increasing importance as the artificial insemination is employed in horses more intensely. Molecular genetic markers may be useful tools to evaluate the stallion fertility before breeding. The prolactin receptor gene (PRLR) was chosen as a candidate for stallion fertility because of its influence on testicular and accessory sex gland function. Screening the equine PRLR gene for polymorphisms in Hanoverian stallions revealed two single nucleotide polymorphisms (SNPs). Association and haplotype analyses were performed in 162 Hanoverian warmblood stallions for these intragenic SNPs using the least square means (LSM) of the pregnancy rate per oestrus for stallions and the paternal component and embryonic component of the breeding values (BV) of the pregnancy rate per oestrus. The two SNPs (BIEC2‐589441, BIEC2‐560860) showed significant associations using single marker and haplotype analysis with the embryonic and paternal component of BV and one SNP (BIEC2‐560860) was also significantly associated with the LSM of the pregnancy rate per oestrus. This is the first report on an association of PRLR‐associated genetic markers with fertility traits in stallions. 相似文献
994.
M. C. Makrakis L. E. Miranda S. Makrakis D. R. Fernandez J. O. Garcia J. H. P. Dias 《Ecology of Freshwater Fish》2007,16(3):410-416
Abstract – We studied the migratory behaviour of armado, Pterodoras granulosus , in the Paraná River Basin of Brazil, Paraguay and Argentina, during 1997–2005. This species invaded the Upper Paraná River after upstream dispersal was facilitated when Itaipu Reservoir inundated a natural barrier. Fish were tagged ( N = 8051) in the mainstems of the Yacyreta and Itaipu reservoirs, bays of major tributaries, the Paraná River floodplain above Itaipu Reservoir, and below dams. In all, 420 fish were recaptured of which 61% moved away from the release area. Fish moved a maximum of 215 km (mean 42), and at a maximum rate of 9.4 km·day−1 (mean 0.6). Of the 256 armados that moved away from the release site, 145 moved upstream towards unimpounded stretches of the Paraná River and 111 moved downstream into the reservoir and bays of its tributaries (maximum 150 km). Based on the observed migratory movements, we suspect that most of the reproductive output originates in tributaries to the reservoirs. The ability of this species to expand its range presents a conundrum by pitting fishery management interests against conservation needs. Maintenance of the important armado fisheries depends on the ability of the species to migrate freely to use spawning and nursery areas in reservoir tributaries and floodplains. However, its ability to migrate long distances can allow this non-native species the opportunity to invade most of the Upper Paraná River. 相似文献
995.
Hovey EO 《Science (New York, N.Y.)》1904,20(504):281-282
996.
997.
998.
(1) Solutions of many fruit pigments act as indicators. (2) These solutions are easily prepared and stable, and the pH range of their color changes is in most cases conveniently near the neutral point (3) As liquid indicators they can be used in titrating acids, but not bases (4)Their greatest usefulness depends upon the fact that very satisfactory test papers can be made with them in a simple and inexpensive way. 相似文献
999.
Hershey OH 《Science (New York, N.Y.)》1901,13(335):869-871
1000.
Dipterous blood-sucking insects (horseflies, black flies, gnats, midges) have negative impacts on the performance of draught horses in forest enterprises. For the protection of these animals, the following preparations were applied at the interval of 24 hours: diethyltoluamide, Oxamat (N,N-diethyloxamine acid, USSR) and Stomoxin (synthetic pyrethroid, product of the firm Wellcome, England). In the course of 66 working days, the performance of test animals treated with 10% water emulsion of diethyltoluamide increased by 49.25 cu. m. of skidded wood, i.e. by 0.74 cu. m. wood per horse/day (21.65%), as compared with the control group. The daily savings of prime costs per test horse/day made 16.99 Kcs (Czechoslovak crowns). In comparison with the control group, the performance of horses treated with 5% water emulsion of Oxamat increased by 85.50 cu. m. wood, i.e. by 1.29 cu. m. wood per horse/day (38.00%). Stomoxin at the concentration of 0.05% acted as a good insecticide but had no marked repellent effect. The results of this study document that the production of effective repellents should be introduced in the Czechoslovak Socialist Republic. 相似文献