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651.
Comparison of solvents and methods of extracting methylbenzimidazol-2-yicarbamate (MBC) from tobacco
The bioautographic method of Homans and Fuchs for detecting MBC on thin layer plates, was tested quantitatively. The sum of the vertical and horizontal diameters of the zones of inhibition of Penicillium expansum, and the square root of the mass of an equal area of paper, were directly proportional to the logarithm of the concentration of MBC. Methanol and ethanol extracted significantly more MBC from tobacco tissue than acetone and chloroform. Soxhlet extraction was more effective than cold (22 °C) treatment, but the latter, in which 100 mg aliquots of dried tissue were used, was the least variable, very much quicker and could be used to detect the fungicide in small amounts of individual plant tissues. 相似文献
652.
P A Fernandes R A Bowen H R Sawyer T M Nett T A Gorell 《American journal of veterinary research》1989,50(1):64-67
Receptors for estrogen and progesterone were measured in cytosols prepared from specimens of canine endometrium obtained at late proestrus, day 4 of estrus, day 2 of diestrus, and at 10 day intervals from days 10 through 80 of diestrus. Twenty nine adult bitches were used, with 2 to 4 dogs used at each time point. Concentrations of estradiol receptors measured in endometrial cytosols from late proestrus through day 10 of diestrus were similar (mean +/- SEM: 9.9 +/- 2.2, 10.5 +/- 1.2, 16.3 +/- 1.6, and 16.2 +/- 2.9 pmol/g of tissue at proestrus, day 4 of estrus, days 2 and 10 of diestrus, respectively). As serum concentrations of progesterone increased during early diestrus, the concentration of estradiol receptors decreased and were significantly (P less than 0.05) lower on days 30 (4.9 +/- 1.3 pmol/g of tissue) and 40 (3.7 +/- 0.6 pmol/g of tissue) of diestrus. After day 40 of diestrus, when serum concentrations of progesterone were approaching basal concentrations, the concentration of estradiol receptors increased and remained significantly (P less than 0.05) higher from days 60 to 80 of diestrus (day 60, 13.4 +/- 2.9; day 70, 15.7 +/- 1.7; day 80, 19.8 +/- 2.4 pmol/g of tissue). As observed for estrogen receptors, the concentration of endometrial receptors for progesterone also gradually increased from late proestrus (4.9 +/- 1.3 pmol/g of tissue) to day 2 of diestrus (6.4 +/- 0.3 pmol/g of tissue).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
653.
Ricardo Henrique Ribeiro Marcos Renan Besen Priscila Luzia Simon Cimelio Bayer Jonatas Thiago Piva 《Soil Use and Management》2020,36(3):420-428
Nitrogen (N) gas losses can be reduced by using enhanced-efficiency N (EEN) fertilizers such as urease inhibitors and coating technologies. In this work, we assessed the potential of EEN fertilizers to reduce winter losses of nitrous oxide (N2O-N) and ammonia (NH3-N) from a subtropical field experiment on a clayey Inceptisol under no-till in Southern Brazil. The EEN sources used included urea containing N-(n-butyl) thiophosphoric triamide (UR+NBPT), polymer-coated urea (P-CU) and copper-and-boron-coated urea (CuB-CU) in addition to common urea (UR) and a control treatment without N fertilizer application. N2O-N and NH3-N losses were assessed by using the static chamber method and semi-open static collectors, respectively. Both N2O-N and NH3-N exhibited two large peaks with an intervening period of low soil moisture and air temperature. Although the short-term effect was limited to the first few days after application, UR + NBPT urea decreased soil N2O-N emissions by 38% relative to UR. In contrast, urease inhibitor technology had no effect on NH3-N volatilization. Both coating technologies (CuB-CU and P-CU) were ineffective in reducing N losses via N2O production or NH3 volatilization. The N2O emission factor (% N applied released as N2O) was unaffected by all N sources and amounted to only 0.48% of N applied—roughly one-half the default factor of IPCC Tier 1 (1%). Based on our findings, using NBPT-treated urea in the cold winter season in subtropical agroecosystems provides environmental benefits in the form of reduced soil N2O emissions; however, fertilizer coating technologies provide no agronomic (NH3) or environmental (N2O) advantages. 相似文献
654.
Thiago Vilar Silva Benner Geraldo Alves Kele Amaral Alves Regiani Nascimento Gagno Porto Maria Lucia Gambarini 《Tropical animal health and production》2017,49(6):1179-1185
The effects of calving season [rainy (RS) and dry (DS)] on the voluntary waiting period (VWP) of 58 Holstein cows raised in the tropical savannah were investigated using data of temperature humidity index (THI), total antioxidant status (TAS), respiratory rate (RR), rectal temperature (RT), glucose, total cholesterol (TC), triglycerides (TG), velocity of uterine regression, and subsequent reproductive performance. Blood samples and clinical data were taken once every week, from calving until the sixth postpartum week. Reproductive data were collected until 180 days postpartum. THI differed between seasons (P < 0.05], as well as TAS (P < 0.001), RR (P < 0.001), RT (P < 0.01), glucose (P < 0.001), TC, and TG (P < 0.05), with higher values in RS. Although the velocity of uterine regression showed to be slower (P < 0.001) during RS, no differences were present regarding uterine health. Days open increased in RS (P < 0.001), but the number of services/conception was similar (P = 0.33). The results suggested cows under heat stress during the rainy season in the tropical savannah are more susceptible to a decline in the reproductive performance due to oxidative, metabolic, and uterine health problems. 相似文献
655.
de Souza Rosés Thiago Andreolla Ana Paula de Figueiredo Soveral Lucas Vieira Maria Isabel Botelho Kich Jalusa Deon Frandoloso Rafael Kreutz Luiz Carlos 《Tropical animal health and production》2020,52(2):619-623
Tropical Animal Health and Production - Trichinellosis is a zoonotic disease exotic in Brazil but commonly found worldwide including South American countries like Argentina. International trading... 相似文献
656.
657.
Maria Isabel Gonzalez Urrego Raquel Silveira Pedreira Karine de Melo Santos Mariane Ceschin Ernandes João Paulo Fernandes Santos Thiago Henrique Annibale Vendramini Marcos Nogueira Eberlin Julio Cesar de Carvalho Balieiro Cristiana Ferreira Fonseca Pontieri Marcio Antonio Brunetto 《Journal of animal physiology and animal nutrition》2021,105(Z1):65-75
The strong odour of faeces and excessive production of gases in some dog breeds have long been a concern of owners. The pet food industry uses nutritional alternatives, such as high-quality ingredients and additives, to improve the odour of faeces. However, there are still some dog breeds, such as the French Bulldog, that present this problem due to the presence into the large intestine of indigested protein. Therefore, a deeper understanding of the volatile compounds that influence the odour of dog faeces is important. This study aimed to identify changes of faecal odour compounds that are most prevalent in French Bulldogs based on food containing different high-quality protein sources and their effect in sensory analysis. Four maintenance foods with different protein sources were formulated: P, poultry meal food; W, wheat gluten food; PW, poultry meal and wheat gluten food; and PWH, poultry meal, wheat gluten, and hydrolysed protein food. Eight adult French Bulldogs were arranged in a 4x4 Latin square design and adapted to foods for 28 days. Fresh faeces were collected for analysis of volatile organic compounds (VOCs) and sensory analysis. The means were compared by SAS, and statistical significance was indicated by p ≤ 0.05. No adverse effects were observed in the animals regarding VOCs, and a significant difference was observed in two of the 68 compounds identified. The animals fed a P food had higher concentrations of phenol in the faeces, whereas the indole compound was present at higher concentrations in animals fed the W food. P food was associated with higher odour perception during sensory evaluation. In summary, the source of protein in the foods had little impact on the composition of VOCs, and a greater perception of the odour was determined by sensory analysis when foods containing animal protein were administered. 相似文献
658.
J. Schade J. H. Fonteque T. R. Muller W. T. Teixeira A. C. da Rosa R. A. Casagrande T. G. de Cristo N. C. C. de Azevedo Fernandes 《Equine Veterinary Education》2021,33(10):e382-e385
An 11-year-old Campolina horse was referred to the Veterinary Hospital due to the presence of an exophytic mass located in the rostral region of the mandible. Radiographic evaluation showed no evidence of tumour infiltration in the underlying mandibular bone, and the histopathology and immunohistochemical evaluations confirmed the diagnosis of fibromatous epulis. The treatment included surgical excision of the mass, followed by extensive curettage of the underlying mandibular bone. Complete healing of the wound was evidenced 60 days after the procedure; however, relapse was reported by the owner between 1 and 3 years after surgery. 相似文献
659.
Lateral migration of fishes in Amazon floodplains 总被引:2,自引:2,他引:2
C. C. Fernandes 《Ecology of Freshwater Fish》1997,6(1):36-44
Abstract— Migrations of fish in the outlet channel of Lago do Rei, a floodplain lake on Careiro Island in the Amazon River, were examined using three capture methods. Of the 85 species found in the Parana do Rei (channel), 20 migrated between the lake and river. Migrations from the lake to the river occurred in two pulses. In August-September, as the river water level began to recede, some fish migrated to the river with the current. As the river water level rose in December-January, additional fish migrated towards the main river against the current. Fish returned to the lake by March or April after they had spawned. The migratory patterns of six species, family Curimatidae and Prochilodontidae: Potamorhina latior, Psectrogaster amazonica , P. rutiloides, Curimata kneri, Prochilodus nigricans and Semaprochilodus taeniurus are described in detail. Lateral migrations of fish in this ecosystem appear to be closely linked to breeding and to physical habitat changes related to river water level. 相似文献
660.