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Chlorpheniramine (CPA) is an antihistaminic that changes the conformation of DNA and inhibits polyamine biosynthesis in mammalian cells. In the present work, we tested the effect of CPA on four genera of fungi species (Altemaria alternata, Botrytis cinerea, Cladosporium cladosporioides and threePenicillium spp.) grownin vitro. Similar growth inhibitions of these genera were produced by 0.5 raM iprodione, CPA and histidinol, but CPA was the most effective. The CPA sensitivities of the twoB. cinerea strains were different. Putrescine did not restore the fungal growth inhibited by CPA.  相似文献   
3.
Citrus huanglongbing (HLB), associated with Candidatus Liberibacter asiaticus and Ca. L. americanus and transmitted by the Asian psyllid Diaphorina citri, is the most serious disease of citrus worldwide because of crop devastation and difficulty to control. Since 2004, approximately 3 million trees were eliminated in attempts to limit its spread in Brazil. Where HLB becomes endemic, the disease progression in the orchard and the increasing symptom severity throughout the tree canopy can be relatively fast, greatly reducing the economic life of affected orchards because of tree decline and yield reduction. Although the majority of the fruit from symptomatic branches drop before harvest, a significant amount of affected fruit remain attached, are available for harvest, and can affect juice quality. To quantify and compare the effects of HLB on fruit quality of the most important sweet orange cultivars grown in São Paulo State, 4–6 year-old sweet orange trees from 26 blocks (two of ‘Valencia Americana’, eight of ‘Hamlin’, four of ‘Westin’, seven of ‘Pera’, and five of ‘Valencia’) were selected prior to harvest. In each block, 14–21 HLB-symptomatic trees were chosen. In each tree, the quality of 20 fruit normal in appearance from asymptomatic branches and 20 symptomatic fruit from symptomatic branches were assessed. In general, compared to normal fruit, the symptomatic fruit were small, light, more acidic, and had lower juice percentage, Brix, total soluble solids per box, total soluble solids per fruit, and Brix/acidity ratio. These effects of fruit quality were less pronounced on early and mid season sweet orange cultivars than on late season cv. Valencia.  相似文献   
4.
The aim of this study was to identify possible effects of different vaccination strategies (concomitantly or not) against brucellosis and clostridia on intake, performance, feeding behavior, blood parameters, and immune responses of dairy heifers calves. Fifty heifers calves were enrolled [38 Gyr (Zebu, Bos taurus indicus) and 12 5/8 Holstein Gyr]. At 120 d of age, animals were randomly distributed among 3 groups: B (n = 18), vaccinated against brucellosis; C (n = 14), vaccinated against clostridia and CB (n = 18), vaccinated concomitantly for both. Rectal and thermographic temperatures were evaluated on days 1, 0, 1, 2, 3, 5, 7,10, 14, and 28 relatives to the vaccination day. Feed and water intake, body weight (BW), and feeding behavior were monitored daily by an electronic feeding system. Blood was sampled on days 0, 3, 7, 14, and 28, relative to the vaccination day for determination of glucose and -hydroxybutyrate (BHBA) concentrations. Blood sampled on day 0 (prevaccination) and on days 28 and 42 were used to evaluate the immune response against Brucella abortus and clostridia. There was an increase in rectal temperature between the first and the third day postvaccination in the 3 groups. The thermography revealed an increase of local temperature for 7 d on groups B and CB. Group C had increased local temperature for a longer period, lasting for up to 14 d. Dry mater intake was reduced for groups B and CB, but no alteration was observed for group C. No alterations regarding initial BW, final BW, average daily weight gain, and feed efficiency were observed. No differences were observed for the 3 vaccination groups for blood parameters throughout the evaluation period. The concomitant vaccination against brucellosis and clostridia led to lower neutralizing antibody titers against epsilon toxin of Clostridium perfringens and botulinum toxin type C of C. botulinum (C > CB > B). When cellular proliferation assay and serological tests to B. abortus were evaluated, no differences were observed between groups B and CB. The present results indicate that the concomitant vaccination against brucellosis and clostridia has no relevant impact on the intake, performance, and feeding behavior of dairy calves. However, the concomitant vaccination of vaccines against these 2 pathogens impacts animal immunity against clostridial infections.  相似文献   
5.
Genetic selection for carcass traits is paramount to maximize the profitability and long‐term sustainability of any meat‐producing livestock species. The main objectives of this research were to evaluate the efficiency of indicator traits for the genetic improvement of lamb carcass traits and to determine the value of including carcass traits into terminal sire selection indexes for the Canadian sheep industry. The carcass traits included hot carcass weight (HCW), fat depth at the GR site (FATGR) and average carcass conformation score (AVGCONF), and were measured on heavy lambs (slaughter age less than 365 days and HCW greater than 16.3 kg) in commercial abattoirs. Growth traits were found to be moderately efficient indicator traits for the genetic improvement of HCW but selection on ultrasound traits was necessary to substantially improve the carcass quality traits (FATGR and AVGCONF). Economic selection indexes were designed by adding various combinations of carcass traits into the Canadian Sheep Genetic Evaluation System terminal indexes. Records measured on individuals and progeny were assumed to be the sources of information for live animal and carcass traits, respectively. The changes in index accuracy, efficiency and expected correlated response were used to assess the value of their inclusion. HCW was found to have a large economic value, and its inclusion into terminal selection indexes was expected to substantially increase their accuracy (0.08–0.12 points) and efficiency (20%–30%). However, further including FATGR (measured 110 mm from the carcass midline over the 12th rib) and AVGCONF had little impact on the accuracy (≤0.03) and efficiency (1%–7%) of the proposed indexes. Thus, the inclusion of carcass traits into the existing terminal selection indexes could be beneficial for the genetic improvement of HCW, but further research is needed to determine optimal methods of increasing carcass fatness and muscularity.  相似文献   
6.
ObjectiveTo determine the specific lung elastance (SEL) in anesthetized dogs and to evaluate the efficacy of a SEL-based recruiting airway pressure (RPaw) at improving global and regional lung aeration.Study designRetrospective and prospective clinical study.AnimalsA total of 28 adult dogs were included in the retrospective study and six adult dogs in the prospective study.MethodsRetrospective study: SEL and SEL-based RPaw were determined using previously published data. In mechanically ventilated dogs undergoing thoracic computed tomography (CT), SEL was calculated as ΔPL/(VT/EELV), where ΔPL is the driving transpulmonary pressure, VT is the tidal volume and EELV is the end-expiratory lung volume. The ratio of lung to respiratory system elastance (EL/Ers) was determined. SEL and EL/Ers were used to calculate the SEL-based RPaw. Prospective study: dogs underwent thoracic CT at end-expiration and at end-inspiration using the SEL-based RPaw, and global and regional aeration was determined. For analysis of regional aeration, lungs were divided into cranial, intermediate and caudal regions. Regional compliance was also calculated. A p value <0.05 was considered significant.ResultsThe SEL and EL/Ers were 12.7 ± 3.1 cmH2O and 0.54 ± 0.07, respectively. The SEL-based RPaw was 29.1 ± 7.6 cmH2O. In the prospective study, the RPaw was 28.2 ± 1.3 cmH2O. During RPaw, hyperinflation increased (p = 0.0003) whereas poorly aerated (p < 0.0001) and nonaerated (p = 0.01) tissue decreased. Normally aerated tissue did not change (p = 0.265). Regional compliance was higher in the intermediate (p = 0.0003) and caudal (p = 0.034) regions compared with the cranial region. Aeration did not differ between regions (p > 0.05).Conclusions and clinical relevanceAn SEL-based RPaw reduces poorly and nonaerated lung tissue in anesthetized dogs. In nonsurgical anesthetized dogs, an RPaw near 30 cmH2O is effective at improving lung aeration.  相似文献   
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Abutilon theophrasti (velvetleaf) is a widespread and problematic annual weed. Greenhouse and field experiments were conducted to investigate the effects of different cutting methods on the viability of A. theophrasti seeds. Three cutting methods were assessed: (1) Entire plant cut and dried (EPD)—plants were cut at soil level and dried with capsules attached on the greenhouse bench or soil surface for 4 weeks; (2) capsules detached and dried (CD)—capsules were removed from plants and dried for 4 weeks; and (3) capsules detached and tested while fresh (CF)—a control treatment. Before drying, the developmental stage (stage one, dark green; stage two, light green; stage three, yellowish-green; or stage four, black with the slightly open capsule) and age (days after flowering, DAF) of each capsule was recorded. Seed viability was measured immediately in the CF treatment and after the 4-week drying period in the EPD and CD treatments. No seeds in the EPD and CD treatments were viable when harvested at the first developmental stage (1–8 DAF) in either experiment, but 100% of seeds in the CF treatment in the field were viable when harvested at 8 DAF. In both greenhouse and field experiments, seeds attained full viability at earlier harvest ages in CF than in EPD or CD treatments, suggesting that seeds might become viable relatively early in development but lose viability if allowed to dry. These findings could be applied to optimise late-season mechanical control of A. theophrasti.  相似文献   
9.
A survey program was carried out from June 1988 to august 1989 in North-eastern Italy in a pipe drainage area of 61 ha in order to verify if the year of installation (one part of the system has been installed in 1984 and another one year later) and the cover material of drains (pipes were covered with cocofibre for 2/5 of their length and without envelope for 3/5) could influence the functioning of the system. Collected data of drain discharge and water table depth were subjected to an elaborate statistical analysis.A methodological approach to determine the sample size (how many measurements of discharge and watertable depth are required, in space and time, from a statistical stand-point) in drainage experiment is proposed. For drainage systems similar to the considered one, a sample size of 10–12 drains and 6–8 observation wells can be recommended in order to obtain a standard error lower than 10–15% of the mean.  相似文献   
10.
Landscape Ecology - An understanding of species-habitat relationships is required to assess the impacts of habitat fragmentation and degradation. To date, habitat modeling in fragmented landscapes...  相似文献   
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