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81.
D'Aquino S Schirra M Palma A Angioni A Cabras P Migheli Q 《Journal of agricultural and food chemistry》2006,54(13):4721-4726
The influence of fungicide concentration and treatment temperature on residue levels of pyrimethanil (PYR) in comparison with the commonly used fungicide imazalil (IMZ) was investigated in orange fruits following postharvest dip treatments. The dissipation rate of PYR residues was recorded as a function of storage conditions. The fungicide efficacy against green and blue molds caused by Penicillium digitatum and Penicillium italicum, respectively, was evaluated on different citrus varieties following the fungicide application at 20 or 50 degrees C. Residue levels of PYR in Salustiana oranges were significantly correlated with the fungicide dosage, but residue concentrations were notably higher (ca. 13-19-fold) after treatment at 50 degrees C as compared to treatments at 20 degrees C. After treatment at temperatures ranging from 20 to 60 degrees C, PYR and IMZ residues in Salustiana oranges were significantly correlated with dip temperatures. Dissipation rates of PYR during storage were negligible in both Salustiana and Tarocco oranges. Results obtained on wounded, noninoculated Miho satsumas revealed that when treatments were performed at 50 degrees C, PYR or IMZ concentrations needed to achieve the complete control of decay were 8- and 16-fold less than by treatment at 20 degrees C. When fruits were inoculated with either P. digitatum or P. italicum, the application of 400 mg L(-1) PYR at 20 degrees C or 100 mg L(-1) PYR at 50 degrees C similarly reduced green and blue mold development. These results were corroborated by storage trials on Marsh grapefruits and Tarocco oranges. The lowest concentration of PYR required to achieve almost total protection of the fruit against decay accounted for 100 mg L(-1) at 50 degrees C and 400 mg L(-1) at 20 degrees C, respectively. Treatments did not affect fruit external appearance, flavor, and taste. It is concluded that postharvest PYR treatment represents an effective option to control green and blue mold in citrus fruit and that integration of fungicide applications and hot water dips may reduce the possibility of selecting fungicide-resistant populations of the pathogen, as a consequence of increased effectiveness of the treatment. 相似文献
82.
Borghetti P De Angelis E Saleri R Cavalli V Cacchioli A Corradi A Mocchegiani E Martelli P 《Veterinary immunology and immunopathology》2006,110(1-2):17-25
Taking into account the role played by the neuroendocrine network in affecting the early development of the immune response, the present study aims to assess neonatal immunity in piglets by testing peripheral lymphocyte age-related changes in relationship to plasma levels of some relevant immunoregulatory hormones, such as growth hormone (GH), prolactin (PRL) and cortisol. For this purpose, we studied the peripheral lymphocyte age-related changes in relationship to plasma levels of GH, PRL and cortisol in conventional piglets from birth (day 0) to 41 days of age. A significant decrease was observed in the total number of lymphocytes at day 0, with a subsequent constant increment up to 41 days of age. Concomitantly, the number of T cell subsets (mainly CD8(+) cells and double positive CD4(+)CD8(+)) was low at birth, with strong increments between the 19th and 41st days of life. The CD4(+) T cell number subset was less diminished at birth than that of CD8(+), albeit with significant increments in the post-weaning period. Of interest, gammadelta T cells, which are more involved in innate immune efficiency, displayed the same trend as CD8(+) T cells from birth to the 41st day of life. From day 0 up to the 19th day, significant inverse correlations were found between T cell subsets and GH or PRL or cortisol, albeit with more significant inverse correlations with cortisol. The high levels of GH and PRL in the pre-weaning period may be due to the fact that they have to counteract the cortisol-mediated negative effect on lymphocyte production and development. These findings suggest that stress condition occurs at birth with decreases in the immune parameters, in the same way as in human newborns, with a subsequent gradual normalisation and immune development, as shown by decreased cortisol, GH and PRL normalisation and concomitant increments in T cell subsets. 相似文献
83.
Rivas B Torre P Domínguez JM Converti A Parajó JC 《Journal of agricultural and food chemistry》2006,54(12):4430-4435
Hydrolysates obtained by autohydrolysis-posthydrolysis of corncobs were detoxified with charcoal, concentrated, supplemented with nutrients, and fermented with Debaryomyces hansenii. After biomass removal, the fermented media contained 0.1137 kg of nonvolatile components (NVC)/kg of liquor, which corresponded mainly to xylitol (0.6249 kg/kg of NVC) but also to minor amounts of inorganic components (measured as ashes), proteins, nonfermented sugars (xylose and arabinose), uronic acids, arabitol, and other nonvolatile components (ONVC). The media were subjected to further processing (sequential stages of adsorption, concentration, ethanol precipitation, concentration, and crystallization) to obtain food-grade xylitol. Adsorption experiments were carried out at various solid-to-liquor ratios. Under selected conditions (1 kg of charcoal/15 kg of liquors), the xylitol content increased to 0.6873 kg/kg of NVC, and almost total decoloration was achieved. The resulting liquor was concentrated by evaporation to increase its NVC content to 0.4032 kg/kg of liquor (corresponding to a xylitol concentration of 0.280 kg/kg of liquor), and ethanol was added to precipitate a part of the NVC (mainly proteins, but also uronic acids, ashes, and other nonvolatile compounds). Refined liquors (containing 0.7303 kg of xylitol/kg of NVC) were concentrated again, and ethanol was added (to reach 40-60% volume of the stream) to allow crystallization at -10 or -5 degrees C. Under selected conditions, 43.7% of xylitol contained in the initial fermentation broth was recovered in well-formed, homogeneous crystals, in which xylitol accounted for 98.9% of the total oven-dry weight. Material balances are presented for the whole processing scheme considered in this work. 相似文献
84.
Montagna P McCulloch M Taviani M Mazzoli C Vendrell B 《Science (New York, N.Y.)》2006,312(5781):1788-1791
Phosphorus is a key macronutrient being strongly enriched in the deep ocean as a result of continuous export and remineralization of biomass from primary production. We show that phosphorus incorporated within the skeletons of the cosmopolitan cold-water coral Desmophyllum dianthus is directly proportional to the ambient seawater phosphorus concentration and thus may serve as a paleo-oceanographic proxy for variations in ocean productivity as well as changes in the residence times and sources of deep-water masses. The application of this tool to fossil specimens from the Mediterranean reveals phosphorus-enriched bottom waters at the end of the Younger Dryas period. 相似文献
85.
María S. Serrano Pilar Fernández-Rebollo Paolo De Vita M. Esperanza Sánchez 《European journal of plant pathology / European Foundation for Plant Pathology》2012,134(2):409-414
The susceptibility to Phytophthora cinnamomi of four crops (wheat, oat, vetch, and yellow lupin) commonly planted in rangeland ecosystems in southern Spain was evaluated. By means of in vitro infection experiments, the presence of the pathogen into the roots of yellow lupin (symptomatic) and vetch (asymptomatic) was observed, but never into wheat and oat roots (asymptomatic). It was also demonstrated that yellow lupin stimulated the production of zoospores of P. cinnamomi. Vetch, wheat and oat did not stimulate zoospore production. Under controlled conditions, only yellow lupin induced an increase in the number of viable chlamydospores in the soil. We concluded that the culture of wheat, oat, and vetch in rangelands did not influence the epidemiology of the Quercus root disease, even when asymptomatically-infected vetch is grown, and these crops can constitute an alternative to the culture of yellow lupin in rangeland ecosystems affected by Quercus root rot. 相似文献
86.
Moreno A Chiapponi C Boniotti MB Sozzi E Foni E Barbieri I Zanoni MG Faccini S Lelli D Cordioli P 《Veterinary microbiology》2012,156(3-4):265-276
Three subtypes (H1N1, H1N2, and H3N2) are currently diffused worldwide in pigs. The H1N2 subtype was detected for the first time in Italian pigs in 1998. To investigate the genetic characteristics and the molecular evolution of this subtype in Italy, we conducted a phylogenetic analysis of whole genome sequences of 26 strains isolated from 1998 to 2010. Phylogenetic analysis of HA and NA genes showed differences between the older (1998-2003) and the more recent strains (2003-2010). The older isolates were closely related to the established European H1N2 lineage, whereas the more recent isolates possessed a different NA deriving from recent human H3N2 viruses. Two other reassortant H1N2 strains have been detected: A/sw/It/22530/02 has the HA gene that is closely related to H1N1 viruses; A/sw/It/58769/10 is an uncommon strain with an HA that is closely related to H1N1 and an NA similar to H3N2 SIVs. Amino acid analysis revealed interesting features: a deletion of two amino acids (146-147) in the HA gene of the recent isolates and two strains isolated in 1998; the presence of the uncommon aa change (N66S), in the PB1-F2 protein in strains isolated from 2009 to 2010, which is said to have contributed to the increased virulence. These results demonstrate the importance of pigs as mixing vessels for animal and human influenza and show the presence and establishment of reassortant strains involving human viruses in pigs in Italy. These findings also highlighted different genomic characteristics of the NA gene the recent Italian strains compared to circulating European viruses. 相似文献
87.
88.
Maria S. Serrano Pilar Fernández-Rebollo Paolo De Vita M. Esperanza Sánchez 《Agroforestry Systems》2013,87(1):173-179
Root rot caused by the soil-borne pathogen Phytophthora cinnamomi is leading to significant oak tree mortality in rangeland ecosystems in south western Spain. Susceptibility to P. cinnamomi infections of Q. ilex seedlings with a standard nutrition, deficient in K+, and deficient in Ca2+, was tested. Oaks deficient in K+ showed high values in Ca2+ content and were tolerant to the disease. Nutritional deficiency in Ca2+, however, did not lead to a higher K+ level in plants and induced poorer root development. In addition, K+ plant content does not appear to have any effect on pathogen tolerance. Based on these results, we conclude that satisfactory calcium nutrition may confer Holm oaks with a greater tolerance to root disease caused by P. cinnamomi. For this reason, limestone supplements are recommended as a measure against root rot caused by P. cinnamomi in rangelands in southern Spain, as a good option for control of oak root disease. 相似文献
89.
Robert M. Kirberger Nerissa Stander Nicky Cassel Paolo Pazzi Varaidzo Mukorera Jevan Christie Ann Carstens Eran Dvir 《Veterinary radiology & ultrasound》2013,54(3):212-222
Spirocerca lupi is a common cause of vomiting, regurgitation, and sudden death in dogs that live in tropical or subtropical regions. Sudden death due to aortic rupture may occur with no preceding clinical signs. The purpose of this prospective study was to compare radiographic and computed tomographic (CT) characteristics of aortic lesions in a cohort of 42 dogs with endoscopically confirmed spirocercosis. Dorsoventral and right lateral recumbent thoracic radiographic findings were compared with pre‐ and postcontrast thoracic CT findings. Aortic mineralization was detected using CT in 18/42 dogs (43%). Three dogs had faint diffuse aortic wall mineralization. Using CT as the reference standard, radiographs had a sensitivity and specificity of 6% and 96%, respectively, for detecting aortic mineralization. A total of 20 aortic aneurysms were detected using CT in 15/42 dogs (36%). Using CT as the reference standard, radiographs had a sensitivity and specificity of 86% and 56%, respectively, for detecting aortic aneurysms. Respiratory motion, aortic displacement by esophageal masses and Spirocerca nodules adjacent to the aorta mimicked aneurysm formation on radiographs. Aortic thrombi were seen in two dogs in postcontrast CT images. Findings from this study indicated that aortic mineralization and aneurysm formation are common in dogs with spirocercosis. Findings also supported the use of pre‐ and postcontrast CT as effective methods for detecting and characterizing these lesions. 相似文献
90.
Valentina Vitale Rita Balocchi Maurizio Varanini Micaela Sgorbini Alberto Macerata Claudio Sighieri Paolo Baragli 《Journal of Veterinary Behavior: Clinical Applications and Research》2013,8(5):400-403
Analysis of heart rate variability (HRV) is a noninvasive approach for investigating the sympathovagal balance of the autonomic nervous system. In recent years, HRV has been increasingly evaluated in animal research. In horses, it has been suggested that basal resting conditions can be achieved by restraining them. The aim of this study was to verify how restriction of movement influences HRV i2n horses. Ten healthy standardbred mares were used to measure the electrocardiographic signal under 2 conditions: free to move in the stall and restrained in the stock. Results indicate that the restriction of movement is associated with increased nervous system sympathetic activity not consistent with resting conditions. 相似文献