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131.
The strawberry tree (Arbutus unedo L.) is an underutilized, drought tolerant, fire resistant species with a south western distribution in Europe, and with ecological and putative socio-economical impact in Portugal and Mediterranean countries. Our aim was to develop an appropriate set of molecular markers to enable genetic diversity to be assessed and to fingerprint Arbutus unedo genotypes for breeding and conservation purposes in Portugal. Twenty-seven trees from a broad geographic range were screened with 20 random amplified polymorphic DNA (RAPD primers) and 11 microsatellite markers (SSR). The RAPDs generated 124 bands, 57.3% of which were polymorphic, with an expected heterozygosity of 27%. We cross-amplified 11 SSR primers developed for Vaccinium spp., and 5 were found to be polymorphic in A. unedo, with 75% of expected heterozygosity, a number of alleles of 11.6, a null allele frequency of 7.6% and a polymorphic information content of 71%. Although the SSRs were more polymorphic and informative than the RAPDs, both markers displayed high genetic variability with the gathered data. No geographic pattern was observed in the genetic variation distribution based on both marker systems, and the lack of correlation between genetic and geographical matrices was confirmed by Mantel tests. Likely, no correlation was found between pairwise SSR and RAPD band-sharing matrices. These results and their implications on A. unedo breeding and conservation programs are discussed.  相似文献   
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133.
The effect of coffee on cardiovascular diseases is still controversial. It is known that the process of decaffeination may influence the chemical constitution and, therefore, the biological effects of coffee. This study thus evaluated the effects of decaffeination on the levels of total phenols and chlorogenic acids in Coffea arabica L. samples, as well as the effects of ingesting both integral and decaffeinated coffee on the lipid profile and hemostatic and hematological parameters in normal and hyperlipidemic rats. Samples of integral and decaffeinated lyophilized coffee (Coffea arabica L., planted in Brazil) were used for chemical analysis (total phenols, chlorogenic acid and caffeine contents). For the bioassays, coffee beverages were prepared with non-lyophilized samples (10 % w/v) and were filtered and administered to animals by gavage (7.2 mL/kg/day) over 30 days. On the 31st day after beginning the treatment with coffee beverages, hyperlipidemia was induced to the animals by administering Triton WR-1339 (300 mg/kg body weight). On day 32, blood was taken to determine the lipid profile, platelet aggregation, prothrombin time, partially activated thromboplastin time and hemogram. The contents of both phenolic compounds and chlorogenic acid in the integral coffee beverage were significantly lower than those in the decaffeinated coffee beverage. The animals treated with Triton WR-1339 presented a mixed hyperlipidemia. Although the decaffeination process caused a relative increase in total phenols and chlorogenic acids, the coffee drinks were unable to change the lipid profile or the hemostatic and hematological parameters in the studied animals.  相似文献   
134.
A variety of methods have been developed to use bovid postcranial elements in the functional morphology approach to paleohabitat prediction. This study represents a first attempt at testing morphometric methods based on astragalus and phalanges on extant mountain‐dwelling bovids and insular fossil bovids from Sardinia assigned to the so‐called ‘Nesogoral group’, already regarded as close to the Caprini tribe. We intended to answer the questions whether a classic four‐habitats model could be successfully applied to extant mountain‐dwelling bovids, and whether results obtained could support the hypothesis of a radiative evolution for the Sardinian bovids. Results obtained, on the one hand, highlighted some inadequacies of the method if not applied to African bovids; on the other hand, they stressed the difficulties of discriminating habitat preferences of Sardinian taxa only based on biometry of astragalus and phalanges. Nonetheless, statistical habitat predictions suggest the contemporaneous presence in Sardinia of bovids having about the same size, but inhabiting different environments, giving support to the hypothesis that Sardinian representatives of the genus Nesogoral originated from a still unknown ancestor by an adaptive radiation evolutionary process.  相似文献   
135.
Dog population dynamics in shelters often requires the grouping of individuals, and changes to the composition of those groups. We developed a protocol to maximize the positive effects and reduce the negative effects associated with grouping dogs. Twenty-three neutered dogs that had to be grouped participated in the study. Fifteen were adult females, 7 were adult males, and 1 was a juvenile female. The protocol was divided into phases that allowed the use of environmental enrichment (occupational, social, nutritional, and sensorial) and behavioral modification (systematic desensitization and counter-conditioning). There were no fights involving bites during the formation of groups. In 5 (18.5%) of formed pairs, we observed unidirectional manifestations of aggression that did not involve physical contact. Three pairs (10%) could not be formed because we saw bidirectional aggression manifestation involving physical contact but no bites. The proposed protocol is a viable alternative to improve grouping of dogs in the context of shelters. The protocol also has the potential to promote wellness, enhance production of desirable behaviors, and decrease the presence of behavioral problems.  相似文献   
136.
Micropropagated plantlets of OH x F 51 and GF 677, respectively pear (Pyrus communis L.) and peach (Prunus persica x Prunus amygdalus) clonal rootstocks were inoculated during an early weaning stage of acclimatization with Glomus sp. Both rootstocks were well colonized, although the infection of OH x F 51 spread more slowly. At the end of initial vegetative growth, mycorrhizal plants of both rootstocks showed a three-fold increase in shoot length over control plants. Mycorrhizal plants also had longer internode and greater fresh mass. The root/shoot ratio was especially altered by arbuscular mycorrhizal inoculation in OH x F 51 plants, which showed a greater increase in shoot rather than in root biomass. The growth-promoting ability of endomycorrhizal fungus persisted throughout the experimental period: Glomus sp. induced a greater development of both rootstocks in the second growing year, after overwintering. Colonization of micropropagated plants by arbuscular mycorrhizal fungus appears to alter the carbohydrate status in stems and roots. Mycorrhizal plants always had a higher content of total soluble sugar, although there were no differences in soluble carbohydrate concentration between inoculated and uninoculated plants. Starch accumulation was found only in mycorrhizal plants of the peach rootstock.  相似文献   
137.
There is a great demand for the development of novel wound dressings to overcome the time and costs of wound care performed by a vast number of clinicians, especially in the current overburdened healthcare systems. In this study, Cyanoflan, a biopolymer secreted by a marine unicellular cyanobacterium, was evaluated as a potential biomaterial for wound healing. Cyanoflan effects on cell viability, apoptosis, and migration were assessed in vitro, while the effect on tissue regeneration and biosafety was evaluated in healthy Wistar rats. The cell viability and apoptosis of fibroblasts and endothelial cells was not influenced by the treatment with different concentrations of Cyanoflan, as observed by flow cytometry. Moreover, the presence of Cyanoflan did not affect cell motility and migratory capacity, nor did it induce reactive oxygen species production, even revealing an antioxidant behavior regarding the endothelial cells. Furthermore, the skin wound healing in vivo assay demonstrated that Cyanoflan perfectly adapted to the wound bed without inducing systemic or local oxidative or inflammatory reaction. Altogether, these results suggest that Cyanoflan is a promising biopolymer for the development of innovative applications to overcome the many challenges that still exist in skin wound healing.  相似文献   
138.
Many authors attribute the antioxidant activity of brewed coffee to its caffeine content. In addition, caffeine intake has been associated with increased performance during physical exercise. This study analyzed the in vivo effects of drinking caffeinated and decaffeinated instant coffee (8%, w/v) on oxidative stress and antioxidant enzyme activity in the anterior tibialis muscles of rats subjected to intense exercise. It was observed that exercise induced lipid peroxidation (estimated using malondialdehyde) and protein oxidation (evaluated by determining the formation of carbonyl groups) in the muscle (P < 0.05). Decaffeinated instant coffee and caffeine solution did not exhibit antioxidant activity in vivo. Caffeinated instant coffee beverage intake did not induce changes in superoxide dismutase and glutathione peroxidase activities but was able to diminish lipid and protein oxidation in the anterior tibialis muscles of rats after exercise (P < 0.05), contributing to a reduction in the oxidative stress triggered by exercise.  相似文献   
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140.
The purpose of this study was to evaluate the feasibility of proton magnetic resonance spectroscopy (1H MRS) to study the concentration of metabolites in the brain of dogs at 3.0 and 7.0 T. Four healthy male beagles were scanned using 3.0 T and 7.0 T human magnetic resonance imaging (MRI) units. The results obtained showed that all dogs had excellent quality spectra for a small (1 cm3) and large (8 cm3) voxel at 3.0 T, whereas only 2 dogs had high quality spectra at 7.0 T due to insufficient water suppression. 1H MRS at 3.0 T appears to be a reliable method to study metabolite concentrations in the canine brain. The development of more advanced water suppression techniques is necessary to improve the results at 7.0 T.  相似文献   
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