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41.
Els M. Broens Elisabeth A.M. Graat Peter J. Van Der Wolf Arjen W. Van De Giessen Mart C.M. De Jong 《Veterinary journal (London, England : 1997)》2011,189(3):302-305
The prevalence of methicillin resistant Staphylococcus aureus (MRSA) in pigs at abattoirs is higher than in pigs sampled on farms. This study investigated whether MRSA negative pigs can become MRSA positive during transportation from the farm to the abattoir after exposure to other pigs and environmental sources of MRSA. Nasal swabs were collected from four batches of pigs during loading at the farm, on arrival at the abattoir and after stunning. Environmental wipes were taken from lorries after transporting pigs and from lairages after holding pigs. All pigs (n = 117) tested MRSA negative before transportation. On arrival at the abattoir, 12/117 (10.3%) pigs in two batches tested MRSA positive. In lorries that tested positive after transportation, the prevalence of MRSA positive pigs was 21.1%, whereas no MRSA was detected in pigs that had been transported in lorries that tested negative after transportation. At stunning, all batches and 70/117 (59.8%) pigs tested MRSA positive. Pigs can become MRSA positive in the short period of time during transportation from the farm to stunning at the abattoir. 相似文献
42.
Otmar Spring Thines Marco Stefanie Wolf Reinhard Zipper 《European journal of plant pathology / European Foundation for Plant Pathology》2011,131(3):519-527
Sequencing of partial cox2 (part of the mitochondrial cytochrome-c-oxydase (COX) gene) was performed with samples from the oomycete genus Pustula, the white blister rusts of Asteraceae and related families. Sequence comparison uncovered several single nucleotide polymorphisms
(SNPs) between P. spinulosa and host specific strains of Pustula isolated from Senecio vulgaris, Tragopogon pratensis and cultivated sunflower, Helianthus annuus. Based on these differences, specific primers were designed for PCR-based detection of white blister rust strains pathogenic
to sunflower. The specificity of the primers was confirmed by cross testing with DNA from various oomycetes occurring in the
same locality. The limit of detection for DNA of P. helianthicola was 10 pg. This allowed detection with DNA from single sporangia and single oospores. The PCR-based experiments allowed detection
of the presence of sunflower white blister rust in soil samples from fields on which infected plants had been cultivated several
months before. Moreover, the molecular tools were successfully applied to trace the pathogen in asymptomatic tissue of infected
plants, demonstrating the systemic nature of Pustula on sunflower. 相似文献
43.
WOFOST: a simulation model of crop production 总被引:20,自引:0,他引:20
Abstract. The WOFOST simulation model is a tool for analysing the growth and production of field crops under a wide range of weather and soil conditions. Such an analysis is important first to assess to what extent crop production is limited by the factors of light, moisture and macro-nutrients, and second to estimate what improvements are possible. The theoretical concept of a production situation, as modelled by WOFOST, is explained, as is the hierarchy of potential production and water-limited and nutrient-limited production situations in the analysis. The organization of the computer files in the model, the structure of the FORTRAN source program and the available standard sets of data are described briefly. 相似文献
44.
45.
Biochemical characterization of amandin,the major storage protein in almond (Prunus dulcis L.) 总被引:1,自引:0,他引:1
Sathe SK Wolf WJ Roux KH Teuber SS Venkatachalam M Sze-Tao KW 《Journal of agricultural and food chemistry》2002,50(15):4333-4341
The almond major storage protein, amandin, was prepared by column chromatography (amandin-1), cryoprecipitation (amandin-2), and isoelectric precipitation (amandin-3) methods. Amandin is a legumin type protein characterized by a sedimentation value of 14S. Amandin is composed of two major types of polypeptides with estimated molecular weights of 42-46 and 20-22 kDa linked via disulfide bonds. Several additional minor polypeptides were also present in amandin. Amandin is a storage protein with an estimated molecular weight of 427,300 +/- 47,600 Da (n = 7) and a Stokes radius of 65.88 +/- 3.21 A (n = 7). Amandin is not a glycoprotein. Amandin-1, amandin-2, and amandin-3 are antigenically related and have similar biochemical properties. Amandin-3 is more negatively charged than either amandin-1 or amandin-2. Methionine is the first essential limiting amino acid in amandin followed by lysine and threonine. 相似文献
46.
47.
49 of 102 sheep of one production herd, which had returned to oestrus once or twice within the 1985 breeding season, were treated twice in a nine-day interval with the PGF2 alpha analogue Cloprostenol "Jenapharm". 53 animals received an additional dose of 10 micrograms of Gonavet "Berlin-Chemie". A lambing rate of merely 15% was achieved by subsequent term-oriented artificial insemination. 31 sheep still in oestrus one day after term-oriented artificial insemination were served, bringing the lambing rate from synchronisation of oestrus and ovulation to 26% and the lambing result to 154%. Serving of the remaining sheep in 2 subsequent oestric cycles, on balance, yielded lambing rates and results of the remaining sheep in 2 subsequent oestric cycles, on balance, yielded lambing rates and results which were higher with significance than those recorded from untreated sheep in the same herd. 相似文献
48.
49.
Wolf J Vítek M Herrendörfer G Sumpf D 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》1994,111(1-6):209-212
SUMMARY: Correct equations are given to express the parameter estimates of four models for complete diallels as a function of the parameter estimates in the model of Eisen et al. (1983). In recent literature these equations have been partly incorrect. ZUSAMMENFASSUNG: Korrekte Gleichungen für den Vergleich von Modellen in der Diallelanalyse Für die Darstellung der Parametersch?tzwerte von vier Modellen für vollst?ndige Diallele als Funktion der Parametersch?tzwerte des Modells von Eisen et al. (1983), die in der Literatur teilweise fehlerhaft erfolgte, werden korrekte Formeln angegeben. 相似文献
50.