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291.
Elena K. Potokina 《Genetic Resources and Crop Evolution》1997,44(3):199-209
Morphological differences and ecogeographical characteristics of five species from Vicia sativa agg. in the area of former USSR were investigated. The key to V. sativa agg. species and subspecies as well as maps of their areals are presented. A complementary study of polymorphism at the phenotypical level of 58 local weedy and wild populations from different geographical regions was conducted to determine areas with higher variability of morphological characters used for intraspecific taxonomy and cultivar identification. The regions of greatest interest for curators and collectors of V. sativa agg. germplasm are some regions of Transcaucasus (Nagornyi Karabakh, Talysh range, Lenkoran valley) and South of Crimea. 相似文献
292.
293.
Jiménez JB Orea JM Montero C Ureña AG Navas E Slowing K Gómez-Serranillos MP Carretero E De Martinis D 《Journal of agricultural and food chemistry》2005,53(5):1526-1530
Resveratrol is known as a grapevine secondary metabolite with fungicide activity. Its exogenous application on harvested grapes resulted in the reduction of microbial flora growth, and consequently, prolonged shelf life, without affecting the nutritional quality of the fruit. Resveratrol treatment also resulted in being effective on fruit that normally does not accumulate such metabolites as, for example, tomatoes, apples, avocado pears, and peppers. As a result, all treated fruits maintained their post-harvest quality and health longer than the untreated ones. This study demonstrates the potential use of resveratrol as a natural pesticide to reduce post-harvest fungi development on a broad spectrum of fruit types. 相似文献
294.
This research examines changes in four sectors of livestock production, pork, dairy, fed cattle, and beef cows, from 1978 to 1997 by county metropolitan character. Relative changes in the amount of production and the number of producers in a county as well as changes in the average scale of production are examined. The purpose is to identify whether structural differences have emerged between metropolitan and nonmetropolitan Corn Belt counties as a result of industrialization in livestock production. The analysis identifies a divergence in the amount and scale of pork production in metro versus nonmetro regions from 1987 to 1997, coinciding with a period of substantial industrialization in that sector. Little divergence is identified in the scale of dairy, fed cattle, and beef cows operations during the same time period. The findings have implications for farmland preservation and agricultural viability in exurban regions of the Corn Belt. 相似文献
295.
Development of a novel and automated fluorescent immunoassay for the analysis of beta-lactam antibiotics 总被引:4,自引:0,他引:4
Benito-Peña E Moreno-Bondi MC Orellana G Maquieira A van Amerongen A 《Journal of agricultural and food chemistry》2005,53(17):6635-6642
An automated immunosensor for the rapid and sensitive analysis of penicillin type beta-lactam antibiotics has been developed and optimized. An immunogen was prepared by coupling the common structure of the penicillanic beta-lactam antibiotics, i.e., 6-aminopenicillanic acid to keyhole limpet hemocyanin. Polyclonal antibodies raised in rabbits after immunization with this conjugate have been applied for the development of a competitive fluoroimmunoassay (FIA), using a novel fluorescent penicillin {[2S,5R,6R]-3,3-dimethyl-7-oxo-6-[(pyren-1ylacetyl)amino]-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxilic acid, PAAP} as the tracer and penicillin G as the reference antibiotic. Protein A/G covalently bound to an azlactone-activated polymeric support was used for the orientated capture of the antibody-antigen immunocomplexes. Upon desorption from the immunosupport, the emission signal generated by the PAAP-Ab complexes is related to the antibiotic concentration in the sample. The 50% binding inhibition concentration of penicillin G standard curves was at 30 ng mL(-)(1) with a detection limit (10% binding inhibition) of 2.4 ng mL(-)(1) and a dynamic range from 6.0 to 191 ng mL(-)(1) (20-80% binding inhibition) penicillin G. The generic nature of the antiserum was shown by good relative cross-reactivities with penicillin type beta-lactam antibiotics such as amoxicillin (50%), ampicillin (47%), and penicillin V (145%) and a lower response to the isoxazolyl penicillins such as oxacillin, cloxacillin, and dicloxacillin. No cross-reactivity was obtained for cephalosporin type beta-lactam antibiotics (cephapirin), cloramphenicol, or fluoroquinolones (enrofloxacin and ciprofloxacin). The total analysis time was 23 min per determination, and the immunoreactor could be reused for more than 200 cycles without significant loss of activity. The immunosensor has been successfully applied to the direct analysis of penicillin G and amoxicillin in spiked influent and effluent sewage treatment plant water samples with excellent recoveries (mean values for penicillin G and amoxicillin, 99 and 105%, respectively). Results displayed by comparative analysis of the immunosensor with a chromatographic procedure for penicillins showed excellent agreement between both methods. 相似文献
296.
Effects of housing and short-term transportation on hormone and lymphocyte receptor concentrations in beef cattle 总被引:1,自引:0,他引:1
Rosangela Odore Paola Badino Raffaella Barbero Antonio D’Angelo Elena Fraccaro 《Research in veterinary science》2011,90(2):341-345
The experiment was designed to evaluate the effects of housing system and short-term transportation on the pituitary and adrenal response and on blood progesterone concentrations of beef cattle. Since the use of steroid hormones in farm animals has been banned in the EU (Council Directive 96/22/EC), it seems important to study the possible modifications in serum progesterone concentrations induced by stress in cattle. Thirty-two, 6 months old male Piedmontese beef cattle (16 reared in a littered loose house, Group A, and 16 housed in a littered tying stall barn, Group B) were blood sampled at T1 (6 months old), T2 (12 months old), T3 (18 months old, before transportation to the slaughterhouse) and T4 (after transportation to the slaughterhouse) in order to measure hormonal concentrations and lymphocyte glucocorticoid (GR) and β-adrenergic (β-AR) receptor concentrations. Circulating hormone concentrations were measured using commercial radioimmunoassay kits, whereas lymphocyte receptor density was determined through binding assays. In beef cattle housed in tie stall barn a significant increase in serum cortisol concentration was observed at T3, whereas there was no effect of the housing system on blood progesterone concentrations. Short-term transportation caused a significant increase in blood cortisol and catecholamine concentrations in both groups, whereas lymphocyte GR and β-AR significantly decreased in Group A. Our data confirm the activation of the hypothalamic-pituitary-adrenal axis and the catecholaminergic system in short-term transportation and suggest that the stress-induced increase in circulating progesterone concentrations does not exceed the limit established by pending legislation. 相似文献
297.
298.
Souza GS Rodrigues AB Gioffré A Romano MI Carvalho EC Ventura TL Lasunskaia EB 《Veterinary immunology and immunopathology》2011,143(1-2):75-82
Comparative genomics of Mycobacterium spp. have revealed conservative genes and respective proteins differently expressed in mycobacteria that could be used as targets for the species-specific immunodiagnostics. The alanine and proline-rich antigen Apa is a mycobacterial protein that present significant variability in primary sequence length and composition between members of M. avium and M. tuberculosis complexes. In this study, the recombinant Apa protein encoded by the MAP1569/ModD gene of M. avium subsp. paratuberculosis (Map) was used to generate a panel of monoclonal antibodies which were shown to recognize the most important veterinary pathogens of the M. avium complex, specifically Map and M. avium subsp. hominissuis, and which did not cross-react with M. bovis or M. tuberculosis. The produced antibodies were demonstrated to be a useful tool for the species-specific immunofluorescence or immunohistochemical detection of Map in experimentally infected cell cultures or intestinal tissues from cattle with bovine paratuberculosis and, additionally, they may be employed for the discrimination of pathogenic M. avium subspecies via Western blotting. 相似文献
299.
Demeter Z Palade EA Balogh E Jakab C Farkas R Tánczos B Hornok S 《Acta veterinaria Hungarica》2011,59(4):427-432
Here we report a case of canine babesiosis with unusual morphology of the causative agent. A male, seven-week-old Labrador retriever puppy, exhibiting severe anaemia and haemoglobinuria, was presented at the Clinic of Internal Medicine in February 2011. The puppy was euthanised. The most relevant pathological changes were icterus, severe splenomegaly, generalised lymphadenopathy and haemoglobin nephrosis. Samples were collected from various organs for histology within one hour post mortem. Impression smears were also prepared from the spleen after overnight storage at 4 °C. Tissue sections and smears showed the presence of multiple, coccoid intraerythrocytic bodies that measured 1-2 μm and resembled small babesiae. No large piroplasms were seen. DNA was extracted from the spleen, and a conventional PCR was performed for the amplification of a 450-bp region of the 18S rRNA gene of piroplasms. The causative agent was identified as Babesia canis canis, with 99% sequence identity to other European isolates. Sequence identity to B. gibsoni was only 91%. This is the first account to verify that the morphology of the large canine piroplasm, B. canis, can be uniformly small babesia-like post mortem or following the storage of tissue samples. 相似文献
300.