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91.
Parker HG Kim LV Sutter NB Carlson S Lorentzen TD Malek TB Johnson GS DeFrance HB Ostrander EA Kruglyak L 《Science (New York, N.Y.)》2004,304(5674):1160-1164
We used molecular markers to study genetic relationships in a diverse collection of 85 domestic dog breeds. Differences among breeds accounted for approximately 30% of genetic variation. Microsatellite genotypes were used to correctly assign 99% of individual dogs to breeds. Phylogenetic analysis separated several breeds with ancient origins from the remaining breeds with modern European origins. We identified four genetic clusters, which predominantly contained breeds with similar geographic origin, morphology, or role in human activities. These results provide a genetic classification of dog breeds and will aid studies of the genetics of phenotypic breed differences. 相似文献
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94.
通过研究所、协会、农业工程等促进产业联合、交流和合作,是印度尼西亚花卉产业取得快速发展的主要原因。 印尼是一个由许多岛屿构成的国家,但把它称为“花园国度”可能更合适。印尼某些地方的人们对园艺的热衷促进了当地盆栽植物和温床植物生产的繁荣,同时也带动了种苗和营养繁殖材料的生产。 在爪吐岛西部距雅加达2小时路程的Puncak镇周围的旅游区,茂物至万隆公路的两侧,向周末出来旅行的人们销售花卉的摊位越来越多。当地居民出售多姿多彩的矮牵牛吊篮、陶盆栽植的睡莲及其他许多自家花园内 相似文献
95.
Halldor Felde Berg Heidi Cecilie Larsen Spång Bjørg Heringstad Erik Ropstad Anne Hege Alm-Kristiansen Elisabeth Kommisrud 《Reproduction in domestic animals》2020,55(3):401-404
An extended lifespan of spermatozoa following artificial insemination (AI) can make the timing of insemination less critical, as previously demonstrated with immobilized spermatozoa that are gradually released from an alginate gel. The purpose was to examine the in vivo dissolution of SpermVital (SV) alginate gel over time by endoscopy and secondly to assess spermatozoa quality after incubation of the gel. In vivo endoscopy showed SV gel in the uterus 3, 6, 20 and 24 hr after AI, demonstrating the potential release of spermatozoa to the uterus during this period. In utero ex vivo incubation of the semen demonstrated that high motility and viability of sperm cells was sustained following overnight incubation. 相似文献
96.
Heidi Moe Tim Dempster Leif Magne Sunde Ulf Winther & Arne Fredheim 《Aquaculture Research》2007,38(1):91-99
Escapes of cod (Gadus morhua) from sea cages represent an economic problem for farmers and a potential environmental problem. We estimate that 0–6% of cod held in sea‐cage farms in Norway were reported to have escaped each year from 2000 to 2005, which is a high proportion compared with salmon. We interviewed employees at 19 coastal sea‐cage cod farms in Norway to investigate both how and why cultured cod escape and to document cage handling and management strategies that were effective in minimizing escapes. Based on the interviews, we describe five working hypotheses that may explain why a greater proportion of cod than salmon escape: (1) cod are more willing to escape than salmon; (2) cod bite the net cage and create wear and tear; (3) net cages have insufficient technical standards for cod culture; (4) cod are placed in sea cages at considerably smaller sizes than salmon; and (5) cod are more popular feed for predators. Preliminary testing of the hypothesis that cod bite netting and create holes was done by placing pre‐damaged net panels with cut twines and control panels inside sea cages. Holes in the pre‐damaged net panels increased in size over a period of 3 months. The type of damage indicated that biting of netting twines was the likely cause. 相似文献
97.
Leigh Watterworth Bruce Rosa Heidi Schraft Edward Topp Kam Tin Leung 《Water, air, and soil pollution》2006,177(1-4):367-382
Recently, there has been a surge of interest in understanding the survival of Shiga toxin-producing Escherichia coli (STEC) in aquatic environments. Fifteen strains of STEC were monitored, individually, in untreated well water samples incubated at 10 and 22^C for 56 days. The strains were selected from three serogroups (O26, Ol11 and O157) and represented five distinct ERIC (enterobacterial repetitive intergenic concensus)-genotypes. The microcosms were prepared in triplicate and inoculated at an initial cell density of about 7.0 log CFU/ml well water. At 10^C, the cell density of five STEC strains fell below the detection limit of 0.8 log CFU/ml by day 56. Of the ten persisting strains, four showed superior survival with cell densities decreasing to an average of about 5 log CFU/ml while the remaining six strains showed moderate levels of survival, decreasing to an average cell density of about 3 log CFU/ml. At 22^C, strain H32 (genotype I) and H15 (genotype B) persisted at 1.1 log CFU/ml and 2.2 log CFU/ml in 56 days, respectively. The other 13 STEC strains dropped below the detection limit between weeks 3 to 8. The 15 strains demonstrated highly variable levels of survival with no correlation between ERIC-genotypes or serogroups and the strains' ability to persist in the well water samples. Although strain H32 (O157:H7) persisted significantly longer than strain H22 (O157:H7) in natural well water at both 10 and 22^C, both strains survived equally well in sterile well water, indicating that individual STEC strains vary in their ability to compete with background microbial populations. 相似文献
98.
Mikkelsen H Aagaard C Nielsen SS Jungersen G 《Veterinary immunology and immunopathology》2011,143(1-2):46-54
Paratuberculosis is a chronic infection of the intestine of ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP). Early stage MAP infection can be detected by measuring specific cell mediated immune responses, using the whole blood interferon-γ (IFN-γ) assay. Available IFN-γ assays use purified protein derivative of MAP (PPDj) which are complex antigen mixtures with low specificity. The objectives of this study were to evaluate immunogenicity and specificity of 14 novel recombinant antigens for use in the IFN-γ assay and to assess the consistency of IFN-γ responses. The study included blood samples from 26 heifers from a MAP infected herd, collected three times with four to five-week intervals, and blood samples from 60 heifers of a non-infected herd collected once. Heifers of the non-infected herd were used to establish cut-off values for each antigen. The case definition was an animal with ≥ 2 positive tests for ≥ 4 antigens, resulting in 13 cases and 13 non-cases. IFN-γ levels of cases were higher compared to IFN-γ levels of non-cases (P<0.05). The results of the IFN-γ assay using PPDj did not correlate well with the results using the novel antigens. PPDj produced elevated IFN-γ responses of samples from both the non-infected and the MAP infected herd, indicating unspecific IFN-γ responses and showed low consistency. Three latency proteins, LATP-1, LATP-2 and LATP-3 gave positive IFN-γ tests that correlated very well with the case definition suggesting high immunogenicity. Three tested antigens, LATP-2, MAP-1 and MAP-2 have no homologue in the M. avium subsp. avium or M. bovis genome and could be promising diagnostic antigens, especially LATP-2 correlated highly with the case definition. 相似文献
99.
A method for the extraction of agmatine, cadaverine, histamine, phenyethylamine, putrescine, tryptamine, tyramine, and urocanic acid from canned tuna and frozen tuna loin matrices by matrix solid-phase dispersion, followed by separation and quantification of these compounds by ultrahigh-performance hydrophilic interaction chromatography (UHPLC-HILIC) with orbitrap mass spectrometric detection, is described. Tuna samples are dispersed in a CN-silica sorbent and eluted with a mixture of aqueous ammonium formate buffer and acetonitrile. Separation and detection are carried out on an Agilent 1200 high-performance liquid chromatograph coupled to a Thermo Exactive orbitrap mass spectrometer, and metformin is used as the internal standard. Spike recoveries are determined across a range of 20-100 ppm for each compound, and the method is validated with respect to linearity, reproducibility, accuracy, and limits of quantitation and detection. The method is demonstrated to be suitable for use in quantifying these target compounds in the studied matrices. 相似文献
100.
Alpi KM Burnett HA Bryant SJ Anderson KM 《Journal of veterinary medical education》2011,38(2):110-122
Electronic health records (EHRs) provide clinical learning opportunities through quick and contextual linkage of patient signalment, symptom, and diagnosis data with knowledge resources covering tests, drugs, conditions, procedures, and client instructions. This paper introduces the EHR standards for linkage and the partners-practitioners, content publishers, and software developers-necessary to leverage this possibility in veterinary medicine. The efforts of the American Animal Hospital Association (AAHA) Electronic Health Records Task Force to partner with veterinary practice management systems to improve the use of controlled vocabulary is a first step in the development of standards for sharing knowledge at the point of care. The Veterinary Medical Libraries Section (VMLS) of the Medical Library Association's Task Force on Connecting the Veterinary Health Record to Information Resources compiled a list of resources of potential use at point of care. Resource details were drawn from product Web sites and organized by a metric used to evaluate medical point-of-care resources. Additional information was gathered from questions sent by e-mail and follow-up interviews with two practitioners, a hospital network, two software developers, and three publishers. Veterinarians with electronic records use a variety of information resources that are not linked to their software. Systems lack the infrastructure to use the Infobutton standard that has been gaining popularity in human EHRs. While some veterinary knowledge resources are digital, publisher sites and responses do not indicate a Web-based linkage of veterinary resources with EHRs. In order to facilitate lifelong learning and evidence-based practice, veterinarians and educators of future practitioners must demonstrate to veterinary practice software developers and publishers a clinically-based need to connect knowledge resources to veterinary EHRs. 相似文献