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251.
252.
Luis Cláudio de Faria Patrícia Guimarães Santos Melo Helton Santos Pereira Adriane Wendland Simone Ferreira Borges Israel Alexandre Pereira Filho José Luiz Cabrera Diaz Marcelo Calgaro Leonardo Cunha Melo 《Euphytica》2014,199(3):261-272
The common bean breeding program coordinated by Embrapa Arroz e Feijão released 50 new cultivars from 1984 to 2010. The aim of the present study was to estimate genetic progress in terms of seed yield and other agronomic traits achieved by the black-type common bean breeding program in Brazil over the 22-year period from 1985 to 2006. Two types of field experiments were performed to assess genetic progress. In regard to experiments on lines, the three best breeding lines from each of 11 evaluation cycles constituted 33 treatments. These evaluations were made in 20 environments and served to estimate progress in seed yield and seed size because these were the criteria applied in selecting the elite lines. Cultivar evaluations included nine cultivars recommended by Embrapa during the period under investigation, and the evaluations were established in 21 environments. These evaluations served to estimate improvements in reaction to angular leaf spot, plant architecture and tolerance to lodging because cultivars usually exhibit superior phenotypes for such characteristics. Evaluations were performed from 2008 to 2010. Estimated improvement in seed yield was 25.2 kg ha?1 or 1.1 % per year. Improvements were also found in tolerance to lodging (1.7 % per year) and 100-seed weight (0.65 % per year). There was no significant progress for the plant architecture and resistance to angular leaf spot traits. 相似文献
253.
Daniela Bernadete Rozza Ingrid Vervuert Josef Kamphues Cláudio Estêv?o Farias da Cruz David Driemeier 《Journal of veterinary diagnostic investigation》2006,18(5):494-496
The consumption of monensin-containing feed resulted in deaths of water buffaloes from a feedlot in which cattle and buffaloes were kept together. The monensin formulation was recommended only for use in cattle. Anorexia, muscular weakness, dyspnea, and recumbency were the major clinical findings. The most significant gross lesions were focal pale areas in semitendinosus and semimembranosus muscles, in which segmental necrosis of myofibers was seen microscopically. To compare susceptibilities of species to monensin, 3 bovine calves and 3 buffalo calves were orally dosed. At 5, 7.5, and 10 mg/kg of monensin, only the buffaloes became ill and died. Clinical signs initiated 18-20 h postdosing and were comparable to those from field cases. Gross changes consisted of ascites, hydrothorax, hydropericardium, hepatomegaly, and focal pale areas in the myocardium and to a lesser degree in semitendinosus and semimembranosus muscles. Histopathological changes also resembled those from the field cases, but were especially pronounced in the myocardial cells. The hypothesis that buffaloes could have a lower tolerance to monensin than cattle has been supported by experimental cases. 相似文献
254.
Esmelindro AA Girardi Jdos S Mossi A Jacques RA Dariva C 《Journal of agricultural and food chemistry》2004,52(7):1990-1995
The aim of this work is to assess the influence of light intensity (plants with direct sun exposure and in a controlled light intensity) and age of leaves (6-24 months) on the characteristics of the extracts of mate tea leaves obtained from carbon dioxide at high pressures. Samples of mate were collected in an experiment conducted under agronomic control at Industria e Comercio de Erva-Mate Bar?o LTDA, Brazil. The content of selected organic compounds of the extracts was evaluated by gas chromatography together with mass spectrometry. Quantitative analysis of caffeine, theobromine, phytol, vitamin E, squalene, and stigmasterol was performed, and the results showed that field variables exert a strong influence on the liquid yield and on the chemical distribution of the extracts. 相似文献
255.
Zini CA Zanin KD Christensen E Caramão EB Pawliszyn J 《Journal of agricultural and food chemistry》2003,51(9):2679-2686
Headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography and ion-trap mass spectrometry has been used to identify biogenic volatile organic compounds present in the headspace of chopped leaves of Eucalyptus (E.) dunnii, E. citriodora, and E. saligna. A simple HS-SPME method entailing 30 min of extraction at 30 degrees C was developed for this purpose. Thirty compounds were identified in the headspace of 60 juvenile chopped Eucalyptus leaves, and another 30 were tentatively identified. The presence of compounds such as (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene (TMNT), (E,E)-alpha-farnesene, (E,E,E)-3,7,11,15-tetramethyl-1,3,6,10,14-hexadecapentaene (TMHP), beta-caryophyllene, alpha-humulene, germacrene D, and beta-cubebene in the headspace of the leaves but not in the essential oils from the same Eucalyptus trees and information about the infochemical roles of some of these compounds in other living plant systems suggest they might play a bioactive role in Eucalyptus leaves. 相似文献
256.
Prolactin: does it exert an up-modulation of the immune response in Trypanosoma cruzi-infected rats?
Filipin Mdel V Brazão V Santello FH Caetano LC Toldo MP do Prado JC 《Veterinary parasitology》2011,181(2-4):139-145
During the course of infection by Trypanosoma cruzi, the host immune system is involved in distinct, complex interactions with the endocrine system, and prolactin (PRL) is one of several hormones involved in immunoregulation. Although intensive studies attempting to understand the mechanisms that underlie Chagas' disease have been undertaken, there are still some pieces missing from this complex puzzle. Because data are scarce concerning the role of PRL involvement in Chagas' disease and taking into account the existence of crosstalk between neuroendocrine hormones and the immune system, the current study evaluates a possible up-regulation of the cellular immune response triggered by PRL in T. cruzi-infected rats and the role of PRL in reversing immunosuppression caused by the parasitic infection. The data shown herein demonstrate that PRL induces the proliferation of T lymphocytes, coupled with an activation of macrophages and the production of nitric oxide (NO), leading to a reduction in the number of blood trypomastigotes during the peak of parasitemia. During the acute phase of T. cruzi infection, an enhancement of both CD3+CD4+ and CD3+CD8+ T cell populations were observed in infected groups, with the highest numbers of these T cell subsets found in the infected group treated with PRL. Because NO is a signaling molecule involved in a number of cellular interactions with components of the immune system and the neuroendocrine system, PRL can be considered an alternative hormone able to up-regulate the host's immune system, consequently lowering the pathological effects of a T. cruzi infection. 相似文献
257.
Bruno W Minto Cláudia Valéria S Brand?o Gilberto JC Pereira Daniela Campagnol Maria Jaqueline Mamprim Carlos Roberto Padovani José JT Ranzani 《Acta veterinaria Scandinavica》2011,53(1):46
Background
This prospective experimental study evaluated the surgical procedure and results of modular hybrid total hip arthroplasty in dogs.Methods
Ten skeletally mature healthy mongrel dogs with weights varying between 19 and 27 kg were used. Cemented modular femoral stems and uncemented porous-coated acetabular cups were employed. Clinical and radiographic evaluations were performed before surgery and at 30, 60, 90, 120, 180 and 360 days post-operation.Results
Excellent weight bearing was noticed in the operated limb in seven dogs. Dislocation followed by loosening of the prosthesis was noticed in two dogs, which were therefore properly treated with a femoral head osteotomy. Femoral fracture occurred in one dog, which was promptly treated with full implant removal and femoral osteosynthesis.Conclusions
The canine modular hybrid total hip arthroplasty provided excellent functionality of the operated limb. 相似文献258.
Clémence Vannier Chloé Vasseur Laurence Hubert-Moy Jacques Baudry 《Landscape Ecology》2011,26(8):1053-1069
In landscape ecology, the importance of map extent and resolution on the value of landscape indices is widely discussed, but
the information content of the map, mostly derived from remote sensing images, is not. In this study, we sought (1) to understand
the influence of changes in maps’ spatial and spectral resolution of agricultural landscape elements, taking hedgerow networks
as a case study, and (2) to explore how predictions of species distribution might be affected by maps’ resolutions, taking
two carabid species as a case study. To do so, we compared maps from different remote sensors, derived two landscape characterization
variables from the maps related to patterns known to drive ecological processes, and analyzed their predictive power on biological
data distribution to assess the information content of these maps. The results show that (1) the use of several methods, including
landscape metrics, was useful to assess map validity; (2) the spatial resolution of satellite images is not the only important
factor; changes in spectral resolution significantly alter maps; (3) the relevant definition of “hedgerow” to construct functional
maps is species and process specific; thus the different maps are not either good or bad, but rather provide complementary
information; (4) the more a species responds to network structure and over small areas, the less the different maps can be
substitutable one to another. 相似文献
259.
Giunchetti RC Mayrink W Carneiro CM Corrêa-Oliveira R Martins-Filho OA Marques MJ Tafuri WL Reis AB 《Research in veterinary science》2008,84(2):269-277
The immunopathological evaluation of the hepatic compartment associated with parasitism and biochemical findings are essential for understanding the genesis of hepatomegaly in canine visceral leishmaniasis (CVL). Three clinical groups of dogs naturally infected with Leishmania chagasi [i.e., asymptomatic (AD, n=12), oligosymptomatic (OD, n=12) and symptomatic (SD, n=17)] were assessed and compared with a group of non-infected dogs (NID, n=11). Intense reaction of the Kupffer cells, capsule and portal inflammation, and the presence of intralobular granulomas, were observed in the different clinical groups. Dogs in the SD group presented a higher frequency of parasitism compared with the AD group. Inflammatory alterations were more intense in the SD group and were associated with parasitism. Our results indicated an association between histological liver changes and the progression of biochemical alterations according to progression of clinical forms of CVL, and the direct relationship between clinical symptoms and frequency of hepatic parasitism. 相似文献
260.
Ederli NB de Oliveira FC Lopes CW Damatta RA Santos Cde P de Azevedo Rodrigues Mde L 《Veterinary parasitology》2008,155(3-4):323-327
The differentiation of the species of the Libyostrongylus genus is only possible with the obtainment of the adult parasites in the ostriches proventriculus and gizzard. The present work confirms that it is possible to differentiate the infective larvae of L. douglassii and L. dentatus allowing the differential diagnosis of these species by fecal culture. To show this, adult females from both species were collected from ten proventriculus from adult ostriches and separated by species. Both groups were macerated individually added to sterilized feces for standard fecal cultures. The infective larvae were recovered, identified, quantified and measured. All proventriculus analyzed were parasitized by Libyostrongylus spp. and a clear heterogeneous location for each species was observed. The infective larvae from the fecal cultures of macerated L. douglassii presented a mean total length of 874.3+/-33.80 microm, and a short sheath tail (29.5+/-4.11 microm) with acute termination. The infective larvae from the macerated L. dentatus presented mean total length of 856.0+/-43.63 microm, long sheath tail (61.2+/-9.52 microm) with filamentous termination. The mean measures of the tails of both species had a significant difference. The differentiation of the infective larvae of L. douglassii and L. dentatus by fecal cultures will facilitate the diagnosis of both species for further understanding the Libyostrongylus biology. 相似文献