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排序方式: 共有450条查询结果,搜索用时 15 毫秒
441.
Denis J. Murphy 《Euphytica》1955,85(1-3):433-440
Summary Considerable advances in the manipulation of seed oil yield and quality have been made using conventional breeding methods. Newer methods such as induced mutation and wide crosses have also resulted in significant achievements. These techniques, however, are all limited by the gene pool available in the crop of interest and its near relatives. The prospect of diminishing supplies of non-renewable fossil hydrocarbon reserves and the reality of edible crop surpluses have focused attention on the development of industrial oilseed crops. This will require the production of types of seed fatty acids which are not available in the oilseed crop species that are grown at present.The introduction of novel oil crops via domestication is contrasted with the insertion of alien genes into existing oilseeds to create designer crops. The use of molecular genetics to alter the yield and quality of rapeseed oil is discussed, and strategies for the engineering of seven new designer rapeseed varieties are presented. 相似文献
442.
Najat Hannou Pablo Llop Denis Faure María M. López Mohieddine Moumni 《European journal of plant pathology / European Foundation for Plant Pathology》2013,136(4):665-674
Forty Erwinia amylovora strains isolated from the Middle Atlas Mountains in Morocco have been characterized using sequences from tandem repeat of variable numbers (VNTR) as chromosomal markers. Three VNTR sequences were identified and used for studying the genetic diversity of the strains using a PCR fingerprinting method. Thirty nine strains showed high genetic homogeneity, but one strain displayed a profile quite different. We were able to obtain reproducible and characteristic profiles in strains from remote geographical areas, and associated them with each of the primers. Comparative analyses of Moroccan strains with three reference strains from Spain, France and England, were performed. The results revealed some polymorphisms compared with the English and the French strains, but notable similarities were observed with a Spanish strain obtained from plants imported from Belgium. The developed methodology has demonstrated its usefulness for being applied in epidemiological studies. 相似文献
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447.
The conventional theory of metals is in crisis. In the past 15 years, there has been an unexpected sprouting of metallic states in low-dimensional systems, directly contradicting conventional wisdom. For example, bosons are thought to exist in one of two ground states: condensed in a superconductor or localized in an insulator. However, several experiments on thin metal-alloy films have observed that a metallic phase disrupts the direct transition between the superconductor and the insulator. We analyze the experiments on the insulator-superconductor transition and argue that the intervening metallic phase is bosonic. All relevant theoretical proposals for the Bose metal are discussed, particularly the recent idea that the metallic phase is glassy. The implications for the putative vortex-glass state in the copper oxide superconductors are examined. 相似文献
448.
Relationship between biochemical markers and radiographic scores in the evaluation of the osteoarticular status of Warmblood stallions 总被引:1,自引:0,他引:1
Denis Verwilghen Valeria Busoni Monika Gangl Thierry Franck Jean-Philippe Lejeune Laurent Vanderheyden Johann Detilleux Sigrid Grulke Michelle Deberg Yves Henrotin Didier Serteyn 《Research in veterinary science》2009,87(2):319-328
Establishing the osteoarticular status of the horse is often performed by means of radiological screening of the animals. Widespread blood sampling could reveal to be an interesting alternative to this procedure which is time consuming and sometimes technically difficult. The aim of this study was to investigate the relationship between the radiological status of the horses and the levels of biochemical markers of cartilage degradation and synovial inflammation. A specific radiological scoring and classification system was therefore developed and applied on 63 stallions presented for studbook admission. Additionally, groups of horses were established according to the occurrence of osteochondrosis, degenerative joint disease and distal interphalangeal joint effusion. Insulin growth factor-I, myeloperoxidases, Coll2-1 and Coll2-1NO2 were used as blood markers. The combination of the blood parameters did not seem to correlate with the used scoring system. Coll2-1NO2 levels however tended to increase with poorer radiological class and this could therefore potentially be a useful predictor of the osteoarticular status in the horse. Coll2-1 levels were significantly higher in the degenerative joint disease group. A high percentage of horses with distal interphalangeal joint effusion was present in this study and was associated with decreased IGF-I and increased Coll2-1 levels. 相似文献
449.
Van den Eede A Martens A Lipinska U Struelens M Deplano A Denis O Haesebrouck F Gasthuys F Hermans K 《Veterinary microbiology》2009,133(1-2):138-144
Methicillin-resistant Staphylococcus aureus (MRSA) infections do occur in equine patients. Little is known, however, about their origin and the general equine MRSA colonization status. In West European horses in particular, neither the colonization rate nor the present strains or their antimicrobial susceptibility patterns are known. In the present study, a sample of 110 (Belgian, French, Dutch and Luxemburg) horses presented at a Belgian equine clinic was screened for nasal MRSA carriage. An indirect culturing protocol using a 0.001% colistin and nalidixic acid containing broth was compared to a direct agar method. Phenotypic identification following growth on a chromogenic MRSA screening agar (ChromID MRSA) was combined with genotypic analysis (PCR, PFGE, SCCmec, spa, and MLST typing). Antimicrobial susceptibility was tested through disk diffusion. Twelve (10.9%) horses carried MRSA, with the enrichment protocol resulting in a significantly higher isolation rate. None of the isolated strains were typeable through SmaI PFGE. They all harboured SCCmec type IVa or V and belonged to spa type t011 or t1451 of the ST398 lineage. All isolates were tetracycline resistant and sulfonamide and enrofloxacin susceptible. Macrolide, lincosamide, trimethoprim and aminoglycoside susceptibility varied and in total five different antimicrobial resistance patterns were distinguished. These results show that ST398 is certainly present in West European horses. Due to its known interspecies transmission and the structure of the equine industry, the presence of this clone in horses poses a substantial health hazard for both animals and humans. 相似文献
450.
Fedrizzi B Magno F Badocco D Nicolini G Versini G 《Journal of agricultural and food chemistry》2007,55(26):10880-10887
Thirteen sulfur compounds (boiling points from 35 to 231 degrees C), usually considered as possible off-flavoring volatiles, were quantified by a concurrent headspace-solid phase microextraction method coupled with gas chromatography-mass spectrometry (HS-SPME/GC-MS) on 80 not off-flavoring wines of four varieties (Merlot, Marzemino, and Teroldego as red wines and Chardonnay as a white one) and of five vintages produced in the North Italian Trentino region. The results of the research, the first Italian data-bank per variety on such volatiles, allow us to make a comparison with the data of other winegrowing areas, to investigate the aging effect on the considered volatiles, and, finally, to try a variety discrimination using statistical procedures. Dimethyl sulfide, 3-(methylthio)-1-propanol, diethyl sulfide, and diethyl disulfide were found to increase with time whereas 2-mercaptoethanol and ethylmercaptan showed a decreasing trend. Furthermore, the concentration of several compounds was found to be dependent on the variety. For instance, sulfide, disulfides, benzothiazole, and thioalcohols are at higher levels in Merlot wines, whereas thiols and thioacetates are more abundant in Marzemino and Teroldego wines. Chardonnay products, well apart from the other wines, are the poorest in 3-(methylthio)-1-propanol and rather rich in dimethyl disulfide and in diethyl disulfide, mostly in the aged wines. Applying the principal component analysis to the data, it was possible to demonstrate that Chardonnay and Merlot wines are well-discriminated from the Italian native varietal wines, which on their turn are only partially distinguishable among them. A contribution of these compounds to the variety characteristics of wine is reasonable. 相似文献