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1.
X. Wang Y. Jacob S. Mastrantuono J. Bazzano R. Voisin D. Esmenjaud 《Plant Breeding》2004,123(1):79-83
The spectrum and inheritance of resistance to the root‐knot nematode Meloidogyne hapla was studied in the diploid species Rosa multiflora and R. indica. The host suitability of seven rose rootstocks, namely five R. multiflora (K2, K1, Floradale, CE63 and CE65) and two R. indica (CE35 and Maroc) clonal accessions, was evaluated using four geographic isolates of M. hapla. Plants grown under greenhouse conditions were tested at high and durable inoculum pressure of nematodes and rated for nematode infestation five months after inoculation on a 0–5 gall index. Different host suitabilities to M. hapla were demonstrated depending on the nematode isolates: in R. multiflora, the clone K2 had a resistant (R) response to all isolates; the clone K1 ranged from intermediate (I) (isolate ‘Canada’) to resistant (other isolates), Floradale was shown to be intermediate, whereas CE63 and CE65 were moderate to good hosts (H). In R. indica, both rootstocks were good to excellent hosts for the isolate Canada but resistant to all three other isolates, thus expressing an isolate‐specific resistance. A study on the genetics of resistance in R. multiflora to the M. hapla isolate Canada was then conducted using an incomplete diallel cross involving all previous clones except Floradale. A total of 120 hybrid individuals belonging to several progenies representing the cross combinations R × I, R × H, I × H and H × H were evaluated. Individuals of each progeny generally ranged into a monomodal distribution that suggests polygenic inheritance of resistance. In the family Rosaceae, the differences in the resistance genetics to the meiotic species M. hapla and to the mitotic species, M. arenaria, M. incognita and M. javanica are discussed in relation to the reproductive status of the nematodes. 相似文献
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OBJECTIVE: The aim of the present study was to investigate blood pressure (BP) levels and their relationship with different indices of body fat in a group of adolescents, in order to evaluate the prevalence of hypertension and plan preventive and corrective strategies. DESIGN: Cross-sectional study in primary care. SETTING: All high schools in the Aosta Valley region, northern Italy. SUBJECTS: Five hundred and thirty-two adolescents of both sexes, aged 15.4 (standard deviation 0.7) years. The following parameters were measured: body weight, body height, body mass index (BMI), four skinfold thicknesses, body fat mass, waist and hip circumferences and BP. RESULTS: BMI data indicated a high prevalence of overweight subjects in both sexes, but higher in males, while the prevalence rate of obese adolescents was lower. Of the total, 11.8 % of subjects suffered from systolic hypertension, while 6.9 % suffered from diastolic hypertension. In linear correlation analysis, BMI and all adiposity indices, except waist:hip ratio, were found to be significantly associated (P ranging between 0.05 and 0.001) with both systolic BP and diastolic BP in both sexes, with r ranging between 0.152 and 0.359. Multiple regression analysis with the stepwise method showed BMI and body fat mass to have the strongest association (P < 0.001) with BP, with r ranging between 0.275 and 0.359.ConclusionUnless reversed, these conditions are worrying and predict the possible development of cardiovascular disease in adulthood. There is a pressing need to develop a comprehensive medical and nutrition plan, together with preventive and corrective strategies, in school programmes. 相似文献
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Antonia Concetta Elia Valentina Ciccotelli Nicole Pacini Ambrosius Josef Martin Dörr Marilena Gili Mauro Natali Laura Gasco Marino Prearo Maria Cesarina Abete 《Fish physiology and biochemistry》2014,40(4):1055-1068
Oxytetracycline (OTC) is employed in fish farms to contest or prevent bacterial infections. We simulated an OTC treatment at therapeutic level (75 mg kg?1) and at higher doses (150, 300 mg kg?1) for 10 days. A withdrawal period of 10 days was considered for treated carp, carrying out the same chemical and biochemical analyses (total glutathione, superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione S-transferase and malondialdehyde). The aim was to obtain data related to the carryover in muscle and on variations in the antioxidant indicators in liver and kidney. The OTC residual levels in muscle showed a dose–response relationship. After 10 days of treatment at the recommended dose (75 mg kg?1), the mean value in muscle was 295 μg kg?1. After 10 withdrawal days, residues in all treated groups were not entirely eliminated by fish. Residues of recommended 75 mg kg?1 OTC dose were lower than the maximum permitted by EEC regulation: 100 μg kg?1. Disturbance in the antioxidant systems in liver and kidney was recorded in (150, 300 mg kg?1) carp, as well as during the withdrawal period. A lowered superoxide dismutase activity and higher levels of catalase, glutathione peroxidase, glutathione reductase and glutathione were evaluated in liver, while in kidney only higher malondialdehyde and glutathione S-transferase concentrations were recorded for 300 mg kg?1 dose. The therapeutic OTC dose exerted lower effects, and only in liver, enhancement of GPx and GR activities was recorded. After the withdrawal period, altered antioxidant responses in tissues were restored for all three OTC doses. 相似文献
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Biological control of chestnut blight in Croatia: an interaction between host sweet chestnut,its pathogen Cryphonectria parasitica and the biocontrol agent Cryphonectria hypovirus 1 
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Crustaceans Munida (fam. Galatheideae, ord. Decapodi) were fished in the Southern Adriatic Sea and their proteolytic activities were characterized and tested for potential application in cheese manufacturing. Enzymes extracted from whole crustaceans, mainly serine proteases, showed high caseinolytic and moderate clotting activities. Analysis by 2D zymography of the digestive enzymes extracted from Munida hepatopancreas, showed the presence of several isotrypsin- and isochymotrypsin-like enzymes in the range of 20-34 kDa and 4.1-5.8 pI. Moreover, specific enzymatic assays showed the presence of aminopeptidases and carboxypeptidases A and B. Overall, optimum activity was achieved at pH 7.5 and 40-45 °C. Caseinolytic activity, determined both spectrophotometrically and by SDS gel electrophoresis, indicated higher activity on β-casein than on α-casein. Miniature cheddar-type cheeses and Pecorino-type cheeses were manufactured by adding starter, rennet and Munida extracts to milk. Reverse-phase HPLC and MALDI-ToF mass spectrometry showed a more complex pattern of proteolytic products in cheeses made using Munida instead of chymosin. Munida extracts were found to degrade the chymosin-derived β-casein fragment f193-209, one of the peptides associated with bitterness in cheese. In conclusion, Munida digestive enzymes represent a promising tool for development of new cheese products and shorten cheese ripening when used either alone or in addition to calf rennet. 相似文献
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1. The feasibility and accuracy of the cloacal sexing technique in greater rhea chicks was assessed using chicks of two captive populations of greater rhea in Córdoba, Argentina.
2. A total of 46 greater rhea chicks of 2 to 3 months of age were randomly arranged into three groups and the members of each group were sexed by a different operator.
3. A feather of each chick was plucked for sexing through a molecular method and results were used as controls.
4. Sex was correctly assigned by cloacal inspection in 98% of the cases. Chick manipulation was easily performed and no infections or traumatic lesions were observed a posteriori.
5. Cloacal sexing of rhea chicks up to 3 months of age does not affect animal welfare and should be considered an efficient alternative to molecular methods. 相似文献
8.
Polar P de Muro MA Kairo MT Moore D Pegram R John SA Roach-Benn C 《Veterinary parasitology》2005,134(1-2):159-167
Experiments were conducted to determine if Metarhizium anisopliae isolates which are capable of growth at cattle surface temperatures could produce pathogenicity to Boophilus microplus in laboratory and field studies. The diurnal temperature fluctuation on the surface of cattle was monitored. The temperature tolerance of M. anisopliae isolates (ARSEF3297 and IMI386697) was determined and their pathogenicity to B. microplus compared at a standard bioassay temperature (28 degrees C) and at a temperature similar to the cattle surface (31-35 degrees C). The effect of the two isolates on the B. microplus population on cattle under field conditions was determined. The temperature of the fore udder, rear udder, ribs and neck regions of the mixed Holstein cattle fluctuated between 30 and 35 degrees C, in a similar pattern to the prevailing environmental temperature. However, wider fluctuations were obtained on the ears (28-35 degrees C) and spine (30-41 degrees C). The colony radius of both isolates declined as temperature increased, however, the growth of IMI386697 was five times greater than ARSEF3297 at 34 degrees C. At 28 degrees C, the pathogenicity of both isolates to B. microplus was similar, however, at 31-35 degrees C, IMI386697 was more pathogenic than ARSEF3297. Both isolates reduced the B. microplus population on cattle in comparison to the control formulation. However, IMI386697 (8.5+/-0.64 ticks/animal) produced a greater reduction in tick numbers than ARSEF3297 (19.1+/-0.64 ticks/animal). M. anisopliae was re-isolated from 8.9% of the ticks collected from IMI386697 treated cattle as compared to 2.8% of ticks from ARSEF3297 treated cattle. 相似文献
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Dean AJ Clark DJ Stephen JB McBride VA Bassani L Bazzano A Bird AJ Hill AB Shaw SE Ubertini P 《Science (New York, N.Y.)》2008,321(5893):1183-1185
Pulsar systems accelerate particles to immense energies. The detailed functioning of these engines is still poorly understood, but polarization measurements of high-energy radiation may allow us to locate where the particles are accelerated. We have detected polarized gamma rays from the vicinity of the Crab pulsar using data from the spectrometer on the International Gamma-Ray Astrophysics Laboratory satellite. Our results show polarization with an electric vector aligned with the spin axis of the neutron star, demonstrating that a substantial fraction of the high-energy electrons responsible for the polarized photons are produced in a highly ordered structure close to the pulsar. 相似文献
10.
Mihaela Marilena Stancu 《Water, air, and soil pollution》2012,223(7):4495-4505
Constanta harbor has been contaminated for decades with petroleum and petroleum products, which contain different toxic organic solvents. A novel solvent-tolerant bacterium, Vibrio alginolyticus IBBCt2 was isolated from a seawater sample (Constanta harbor). Alkanes (i.e., n-hexane, n-decane, cyclohexane) with logarithm of partition coefficient in n-octanol and water (log P OW )?>?3.35, were less toxic for V. alginolyticus strain IBBCt2, compared with aromatics (i.e., toluene, m-xylene, ethylbenzene) with log P OW? <?3.17. The high organic solvent resistance of V. alginolyticus IBBCt2 could be due to the presence of some catabolic (alkB, alkB/alkB1, todC1, xylM, C23DO) and transporter (HAE1, acrAB) genes. The adaptation mechanisms, underlying cyclohexane, n-hexane, n-decane, toluene, m-xylene, and ethylbenzene resistance in V. alginolyticus IBBCt2 showed a complex response of cells 60?min after solvent shock (i.e., modifications of the cell viability, changes in the membrane??s lipid and protein profile, modifications of the genomic fingerprinting). Exposure of V. alginolyticus IBBCt2 cells to salt stress decreases the organic solvents tolerance of this bacterium. 相似文献