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81.
Although carob (Ceratonia siliqua L.) is of great economic importance little is still known about the pattern of genetic variation within this species. Morphological characteristics based on 31 fruit and seeds of continuous characters determinant for agro-industrial uses, were compared with RAPD and AFLP markers for assessing genetic distances in 68 accessions of carob trees, from different cultivars, varieties and eco-geographic regions of Algarve. Eighteen selected RAPD primers applied to the 68 accessions produced a total of 235 fragments ranging from 200 to 2000 bp, of which 93 (40%) were polymorphic. Four AFLP selective primer combinations generated a total of 346 amplification fragments of which 110 were polymorphic. The average level of polymorphism based on four primer combinations was 31.8%. The phenetic trees based on RAPD and AFLP analyses gave high co-phenetic correlation values, and were found to be consistent in general with the analysis of morphological data, carried out on the same accessions. A number of RAPD and AFLP markers were found to be diagnostic for ‘Canela’ cultivar and 13 wild ungrafted trees. 相似文献
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84.
Association of prognostic features and treatment on survival time of dogs with systemic mastocytosis: A retrospective analysis of 40 dogs
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S. J. Moirano S. F. Lima K. R. Hume E. M. Brodsky 《Veterinary and comparative oncology》2018,16(1):E194-E201
Systemic mastocytosis is a rare phenomenon, with limited information regarding prognostic features and effective treatment of canine patients with this disease. The objective of this study is to determine the impact of certain features and treatments on dogs with systemic mastocytosis. The medical records of 40 dogs from 4 northeastern US veterinary hospitals, with evidence of systemic mast cell disease, were evaluated retrospectively. Variables analysed with relation to overall survival and prognostic significance included treatment protocol used, substage, presence of a cutaneous or visceral tumour, presence of multiple cutaneous Mast cell tumours, grade of the primary tumour and metastatic site(s). Dogs with metastatic disease confined to distant lymph nodes lived longer than those with circulating mast cells in the blood (P = .001), and those with metastatic disease evident in more than 2 sites had a worse prognosis than those with disease in a single location (P = .005). Additionally, administration of chemotherapeutic agents led to increased survival over prednisone therapy alone (P = .008), with the combination of lomustine, vinblastine and prednisone prolonging survival over the tyrosine kinase inhibitor, toceranib phosphate (P = .002). Presence of mast cells in the blood and/or evidence of disease in more than 2 sites indicate widespread dissemination suggesting their use as negative prognostic features. Furthermore, a chemotherapy protocol including combination lomustine and vinblastine therapy may be more effective than toceranib phosphate for the treatment of dogs with disseminated mast cell disease. Overall, patients with systemic mastocytosis have a grave prognosis and more effective treatment options are needed. 相似文献
85.
Corrêa AP Dossi AC de Oliveira Vasconcelos R Munari DP de Lima VM 《Veterinary parasitology》2007,143(3-4):267-274
The aims of this study were to evaluate the immunomodulatory role of TGF-β1, IL-10, and INF-γ in spleen and liver extracts and supernatant cultures of white spleen cells from male symptomatic and asymptomatic dogs, naturally infected by Leishmania (Leishmania) chagasi. Thirty dogs from Araçatuba, São Paulo, Brazil, an endemic leishmaniosis area, were selected by positive ELISA serological reaction for Leishmania sp. and divided into two groups: asymptomatic (n = 15) and symptomatic (n = 15) consisting of animals with at least three characteristic signs (fever, dermatitis, lymphoadenopathy, onychogryphosis, weight loss, cachexia, locomotion problems, conjunctivitis, epistaxis, hepatosplenomegaly, edema, and apathy). After euthanasia, spleen and liver fragments were collected for ex vivo quantification of TGF-β1, IL-10, and INF-γ. Naturally active in vitro produced TGF-β1 was also evaluated in spleen cell culture supernatant. Spleen and liver extract of asymptomatic dogs had higher mean TGF-β1 levels than symptomatic dogs. High concentrations of IL-10 were found in spleen, and mainly in liver extract of both groups. Higher INF-γ concentrations were found in spleen extracts of symptomatic dogs, and in liver extracts of asymptomatic dogs. Extract of this cytokine was lower in spleen extract. Although INF-γ is being produced in canine infection, mean levels of TGF-β1 and IL-10 from spleen and liver extracts were quantitatively much higher; suggesting that immune response in both asymptomatic and symptomatic dogs was predominantly type Th2. 相似文献
86.
Santiago ME Vasconcelos RO Fattori KR Munari DP Michelin Ade F Lima VM 《Veterinary parasitology》2007,150(4):283-290
Blood and bone marrow samples were taken from 112 Didelphis spp., collected between March 2005 and February 2006, from urban and peri-urban areas of Bauru, São Paulo State, Brazil, to evaluate the hypothesis that these animals might constitute a reservoir of Leishmania spp. Anti-Leishmania ssp. antibodies were screened in the serum samples using an enzyme-linked immuno-sorbent assay (ELISA) and the polymerase chain reaction (PCR). PCR was performed on fragments of DNA samples from Leishmania spp. using primers 13A and 13B, and showed a positive outcome in 91.6% of the 112 samples tested. Of the 107 samples analyzed by ELISA, 71% were positive. Evidence of epidemiological risk factors such as a circulating parasite and freely moving vectors suggests that Didelphis spp. may participate in the transmission cycle of Leishmania spp. in Bauru. 相似文献
87.
Invasive Chinese pond mussel Sinanodonta woodiana threatens native mussel reproduction by inducing cross‐resistance of host fish
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Seth W. Donrovich Karel Douda Věra Plechingerová Kateřina Rylková Pavel Horký Ondřej Slavík Huan‐Zhang Liu Martin Reichard Manuel Lopes‐Lima Ronaldo Sousa 《水产资源保护:海洋与淡水生态系统》2017,27(6):1325-1333
88.
Patrícia Pereira De Lima Cibele Soares Pontes Maria de Fátima Arruda 《Aquaculture Research》2009,41(1):53-60
Management practices on most Brazilian shrimp farms have resulted in high expenses for producers and damage to the environment. Applied ethology could provide information on the pattern of shrimp activity, enabling more efficient feeding frequencies. Behavioural activities of the shrimp Litopenaeus vannamei were recorded during different feeding frequencies. The shrimp were kept in aquariums on a 12:12 h light/dark cycle. They were fed commercial ration three (at 6:00, 12:00 and 18:00 hours), four (at 6:00, 10:00, 14:00 and 18:00 hours) or seven times per day (at 6:00. 8:00, 10:00, 12:00, 14:00, 16:00 and 18:00 hours). We observed animals at 15 min?1 aquarium?1 time periods, recording feeding, substrate exploration, swimming and inactivity. Feeding and exploration were the highest for shrimp fed three times per day, swimming was greatest when animals received four feedings, whereas inactivity was higher for shrimp fed seven times per day. There was greater food ingestion between 12:00 and 14:00 hours for animals fed three and four times per day, whereas swimming was high mainly at 18:00 hours for shrimp fed three and seven times per day. The results indicate higher forage‐related activities (exploration/ingestion) when feed was offered three or four times, suggesting optimization in the pattern of shrimp activities based on these feeding frequencies. 相似文献
89.
Elcimara Cardoso Pereira Elzamara Castro Oliveira Elen Monique Oliveira Sousa Hugo Napoleão Pereira Silva Lincoln Lima Corrêa Rosa Helena Veras Mourão Marcos Tavares-Dias Lenise Vargas Flores Silva 《Journal of fish diseases》2020,43(12):1497-1504
This study investigated the acute toxicity (LC50-24 hr) effects of the essential oil of Cymbopogon citratus for adult Argulus sp. and Dolops discoidalis, before and during oviposition. In vitro acute toxicity (LC50-24 hr) was tested using 20, 40, 60, 80, 100, 120, 140 and 160 μg/L of C. citratus essential oil, and two control groups (one with cultivation tank water and one with cultivation tank water + alcohol) were used. Specimens of Argulus sp. and D. discoidalis submitted to acute toxicity were evaluated using histological procedures. The major chemical compounds of C. citratus essential oil were geranial (47.5%), neral (35.6%) and myrcene (6.7%). The LC50-24 hr for Argulus sp. adults was 67.97 μg/L, while for D. discoidalis it was 59.55 µg/L. In the oviposition of both species of argulids, maximum mortality began with treatments of 140 μg/L, while the LC50-24 hr for Argulus sp. and D. discoidalis was 83.98 μg/L and 82.48 μg/L, respectively. In both argulid species exposed to C. citratus essential oil, morphological alterations were observed only in the eyes, and they occurred in the ommatidium and rhabdomeres and were dependent on the concentration of C. citratus essential oil and the parasite species. 相似文献
90.
Patrícia I. Mombach Taida J. Adorian Dirleise Pianesso Thaís S. dos Santos Joziane S. de Lima Silvino S. Robalo Leila P. da Silva 《Aquaculture Nutrition》2019,25(6):1378-1387
The aim of this study was to investigate the prebiotic potential of pectin hydrolysates that were extracted from agroindustrial waste (apple pomace—AP and passion fruit peel—PFP) and were added to the diet of silver catfish (Rhamdia quelen). A 49‐day biological assay was conducted, and five test diets were evaluated: one diet was a control diet and the other four diets included pectin hydrolysates (2.5 and 5 g/kg). At 49 experimental days, biometric data and biological material were collected to determine the performance, plasma and liver and histological parameters and to evaluate the intestinal contents. The results were analysed by the normality test, which was followed by an analysis of the variance; the treatment means were compared by an orthogonal contrast analysis at a 5% level of significance. The inclusion of 2.5 g/kg apple pomace hydrolysates resulted in a greater production of butyric acid, increased thickness of the muscular layer and higher goblet cell count in the intestine. The inclusion of 5 g/kg apple pomace hydrolysates led to a greater concentration of liver protein. Further studies are needed to increase the knowledge about the use of these additives in the diet of silver catfish and to establish levels that allow greater gains for the species. 相似文献