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491.
Alexandra Correia Pedro Ferreirinha Amanda A Costa Joana Dias Joana Melo Rita Costa Adília Ribeiro Augusto Faustino Luzia Teixeira António Rocha Manuel Vilanova 《Veterinary research》2013,44(1):69
The murine model has been widely used to study the host immune response to Neospora caninum. However, in most studies, the intraperitoneal route was preferentially used to establish infection. Here, C57BL/6 mice were infected with N. caninum tachyzoites by the intragastric route, as it more closely resembles the natural route of infection through the gastrointestinal tract. The elicited T-cell mediated immune response was evaluated in the intestinal epithelium and mesenteric lymph nodes (MLN). Early upon the parasitic challenge, IL-12 production by conventional and plasmacytoid dendritic cells was increased in MLN. Accordingly, increased proportions and numbers of TCRαβ+CD8+IFN-γ+ lymphocytes were detected, not only in the intestinal epithelium and MLN, but also in the spleen of the infected mice. In this organ, IFN-γ-producing TCRαβ+CD4+ T cells were also found to increase in the infected mice, however later than CD8+ T cells. Interestingly, splenic and MLN CD4+CD25+ T cells sorted from infected mice presented a suppressive activity on in vitro T cell proliferation and cytokine production above that of control counterparts. These results altogether indicate that, by producing IFN-γ, TCRαβ+CD8+ cells contribute for local and systemic host protection in the earliest days upon infection established through the gastrointestinal tract. Nevertheless, they also provide substantial evidence for a parasite-driven reinforcement of T regulatory cell function which may contribute for parasite persistence in the host and might represent an additional barrier to overcome towards effective vaccination. 相似文献
492.
Farias Nadja Naiara Pereira Freitas Ednardo Rodrigues do Nascimento Germano Augusto Jerônimo Xavier Regina Patrícia Souza de Melo Braz Nádia Dantas Francisco Diego Teixeira Figueiredo Carlos Weiber Silva Gomes Valter Luis Maia Watanabe Pedro Henrique 《Tropical animal health and production》2019,51(1):179-185
Tropical Animal Health and Production - The aim of the current study was to evaluate the addition of fresh and stored copra meal to the diet of meat quails. Two hundred eighty-seven-day-old male... 相似文献
493.
494.
Buffy coat smear or Knott's test: which to choose for canine microfilaria screening in field studies?
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495.
Maxwell C. Wilson Xiao-Yong Chen Richard T. Corlett Raphael K. Didham Ping Ding Robert D. Holt Marcel Holyoak Guang Hu Alice C. Hughes Lin Jiang William F. Laurance Jiajia Liu Stuart L. Pimm Scott K. Robinson Sabrina E. Russo Xingfeng Si David S. Wilcove Jianguo Wu Mingjian Yu 《Landscape Ecology》2016,31(2):219-227
496.
Mauricio Almeida-Gomes Jayme Augusto Prevedello Renato Crouzeilles 《Landscape Ecology》2016,31(4):711-719
Context
Native vegetation is often used as a proxy for habitat to estimate habitat availability in landscapes. This approach may lead to incorrect estimates of the impacts of habitat loss and fragmentation on species, which have not been thoroughly quantified so far.Objectives
We quantified to what extent the loss of native vegetation reflect actual habitat loss by native species in landscapes. We tested the hypothesis that habitat availability declines at greater rates than native vegetation and thus is overestimated when it is quantified on the basis of native vegetation.Methods
Using simulations, we quantified how the loss of native vegetation in artificial and real landscapes affects habitat availability for species with different habitat requirements. We contrasted a generalist species, which uses all native vegetation, with 10 habitat-specialist species classified into three categories (interior, patchy and riparian species).Results
Habitat availability generally declined at greater rates than native vegetation for all specialist species. This pattern was apparent for different specialist species in a broad range of landscape types. Interior species always lost habitat availability more rapidly than the generalist species. Most riparian species lost habitat availability more rapidly than the generalist species. Responses of patchy species were more complex, depending on their dispersal abilities and landscape structure.Conclusions
Habitat availability is likely to be overestimated when native vegetation is used as proxy for habitat, because habitat availability will generally decline at greater rates than native vegetation. Therefore, a species-centered approach should be adopted when estimating habitat availability in landscapes.497.
Maxwell C. Wilson Xiao-Yong Chen Richard T. Corlett Raphael K. Didham Ping Ding Robert D. Holt Marcel Holyoak Guang Hu Alice C. Hughes Lin Jiang William F. Laurance Jiajia Liu Stuart L. Pimm Scott K. Robinson Sabrina E. Russo Xingfeng Si David S. Wilcove Jianguo Wu Mingjian Yu 《Landscape Ecology》2016,31(2):229-230
498.
Carluccio A Contri A Tosi U De Amicis I De Fanti C 《Journal of the American Veterinary Medical Association》2007,230(10):1502-1505
OBJECTIVE: To determine survival rate, complications, and short-term fertility rate after fetotomy in mares. DESIGN: Retrospective study. ANIMALS: 72 mares with severe dystocia. PROCEDURES: Records from 1991 to 2005 were searched for mares with dystocia in which a fetotomy was performed. Data relating to presentation and position of foals; survival rate, complications, and short-term fertility rate in mares; and 45-day pregnancy rate in mares bred 2 to 3 months after fetotomy were recorded. RESULTS: Anterior fetal presentation was detected for 54 of 72 (75%) mares, posterior presentation was detected for 13 (18.1%), and transverse presentation was detected for 5 (6.9%). One fetus in anterior presentation was hydrocephalic. Survival rate after fetotomy was 95.8%. Complications included retained fetal membranes (5.5%), laminitis (6.9%), vaginal and cervical lacerations (2.8%), and delayed uterine involution (2.8%). Mares bred 2 to 3 months after fetotomy had good short-term fertility, with a mean pregnancy rate of 79.4% at 45 days after breeding. CONCLUSIONS AND CLINICAL RELEVANCE: The survival rate was high, compared with rates reported after cesarean section, and short-term fertility rate was similar to those reported for mares that had a controlled vaginal delivery or cesarean section. Fetotomy performed by a skilled veterinarian on a nonviable fetus should be considered as a means of quick and safe correction of dystocia that does not necessarily impair short-term fertility in affected mares. 相似文献
499.
OBJECTIVE: To evaluate the impact of a low-cost nutritional intervention in changing the lifestyle of adults. DESIGN: Randomised clinical trial. SETTING: Primary health-care centre in S?o José do Rio Preto, S?o Paulo State, Brazil. SUBJECTS: We randomly assigned 104 adults (83 women and 21 men aged 30-65 years, body mass index 24-35 kg m(-2), non-diabetic) into two groups: nutrition counselling and control. Each subject in the intervention group received three individualised nutritional counselling sessions during the first 6 months aimed at increasing intakes of fruits, vegetables and olive oil, reducing saturated fat and improving physical activity. Body composition, biochemical indicators and lifestyle were assessed at baseline and at 6 months and 1 year in both groups. RESULTS: After 6 months of follow-up, body weight, waist circumference, diastolic blood pressure, fasting blood glucose, total and low-density lipoprotein cholesterol, total and saturated fat, and dietary energy and cholesterol levels showed a more significant decrease among subjects in the intervention group than in the control group (P < 0.05). Moreover, the intervention group showed significantly greater improvement in each intervention goal, such as reduced intake of saturated fat and increased intakes of fruits, vegetables, fibre and olive oil (P < 0.05). After 12 months of follow-up, most of the outcomes were maintained. CONCLUSIONS: The low-cost nutritional intervention programme improved serum lipids profile and weight control, and appeared to be feasible for use at a primary health-care centre in a developing country. 相似文献
500.
Gambacorta A Tofani D Bernini R Migliorini A 《Journal of agricultural and food chemistry》2007,55(9):3386-3391
The unprecedented acetonide of the antioxidant hydroxytyrosol has been synthesized by a two-step high-yielding procedure and found to be both purifiable by chromatography and stable over a wide pH range. The protection stabilizes hydroxytyrosol against oxidation, thereby allowing long-term storage. The protection can quantitatively be removed, under nonaqueous conditions, to afford pure hydroxytyrosol suitable for use as an additive in food and cosmetic preparations. Extension of the same methodology to the natural and easily accessible glycoside oleuropein, followed by saponification of the resulting complex mixture of acetonides, allowed hydroxytyrosol acetonide to be recovered in high yield. This constitutes a new interesting methodology to obtain the antioxidant hydroxytyrosol. 相似文献