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In the experiment carried out on 15 lowland black and white cows aged 2—3 years in the 4—5th month of lactation a possibility of measurement a biotransformative activity of the liver (activity of microsomal monooxygenase connected with cytochrome P-450; MMO-P-450) on the basis of antipyrine (phenazone) elimination rate from milk was examined. Antipyrine was applied intravenously at a dose of 15 mg/kg bw. Blood and milk samples were collected before 0 time and after 1, 2, 4, 6, 8, 12, 18 and 24 h after administration of the test solution. The values of antipyrine pharmacokinetic parameters (Co-initial concentration, V₄-volume of distribution, ∆'-coefficient of distribution, k-constant elimination rate, t₀.₅-half life, ClĄ-metabolic clearance) calculated on the basis of antipyrine concentrations changes in plasma and milk were very similar and the observed differences were not significant. The obtained data showed that in cows is possible to determine precisely the activity of enzymatic system MMO-P-450 and hence consequently the rate of liver biotransformation on the basis of antipyrine elimination rate from milk.
The aim of this study was to compare the pharmacokinetics of paracetamol in calves of the BW (Black- -and-White) breed and cross-breed calves (BW × HF Holstein-Friesian) (50% HF). The effect of age on interbreed differences in the values of selected pharmacokinetic parameters of this model drug were also examined. The experiment was carried out on 20 healthy calves: 10 of BW breed and 10 cross-breed (50% HF). The paracetamol test was performed on calves aged 10, 20 and 40 days of life. The animals received this model drug per os at a dose of 5 mg/kg body weight. The concentration of paracetamol in plasma was determined by the spectrophotometric method. The pharmacokinetics of paracetamol were calculated through a non-compartmental method, using The TopFit computer software. The obtained results indicate that the age of calves had an influence on the values of pharmacokinetic parameters of paracetamol. We observed that most of the estimated pharmacokinetic parameters of this model drug differed significantly (P < 0.01) between 10, 20 and 40-day-old calves. It was stated that 10 and 20-day-old BW calves metabolized paracetamol faster compared to 50% HF calves, but the observed results differed insignificantly (P > 0.05). We also observed that 40-day-old 50% HF calves metabolized paracetamol at a significantly (P < 0.01) quicker rate compared to BW animals.
The affinity between the volume of erythrocytes and the content of total water was studied in 12 calves, lowland black and white breed, aged 14—28 days. The examinations were performed on day 14, 21 and 28 of animals’ life. It was found a signi­ficant positive correlation between the total volume of erythrocytes and the content of total water. The indices of the correlation on days 14, 21, and 28 were + 0.955, +0.960, and +0.962. respectively. The data obtained point to the possibility to assess the volume of total water in the first months of calves’ life ta­king into consideration the total volume of erythro­cytes.
Birds and bats using buildings as a place of breeding or shelter.The presence of birds and bats was analysed in buildings intended for thermal refurbishment. Study material was collected in the years 2012-2016 in 336 buildings from 11 voivodships. For detailed analyses concerning birds, data from three voivodships were selected: kujawsko-pomorskie, łódzkie and mazowieckie. To determine differences in the location of bat roosts, buildings from all voivodships were compared. Bird nesting places and daytime bat roosts were divided into 22 locations. Regional differences in the occupation of buildings were analysed. For comparison, the analysed buildings were divided into churches, tenements, public buildings, and residential blocks. Buildings used by birds were also compared with respect to the degree of urbanization of their surroundings. Species-specific differences in their preference for occupying buildings of different types were analysed in birds. Birds were found in 78.9% of buildings and bats – in 8.9% of buildings. 2,250 bird nests in 265 buildings and over 1,000 bats in 30 buildings were inventoried. The bird species most often found in buildings were: the swift Apus apus (40.5%), house sparrow Passer domesticus (31.7%) and jackdaw Corvus monedula (9.9%). Bat species found in buildings included: the common noctule Nyctalus noctula, serotine bat Eptesicus serotinus, lesser horseshoe bat Rhinolophus hipposideros, pipistrelles Pipistrellus and long-eared bats Plecotus. The house sparrow most often inhabited buildings in kujawsko-pomorskie voivodship and the swift most often inhabited buildings in mazowieckie and łódzkie voivodships. Birds in kujawsko-pomorskie voivodship most often built their nests under roofs and birds from mazowieckie and łódzkie voivodships in flat roof spaces. A total of 31 bat roosts were located in 30 buildings in five different locations. Bats most often occupied flat roof spaces and attics and least often occupied crevices behind the gutter.
The aim of the study was to investigate the effects of age on the pharmacokinetics of paracetamol (as a model drug) in calves. The experiment was carried out on 15 healthy BW (Black-and-White) breed calves. Paracetamol (5 mg/kg bw.) was administered per os on day ten, fourteen and twenty of the calves' lives. The concentration of a model drug in plasma was determined by the spectrophotometer method. Pharmacokinetic parameters were estimated through a non-compartmental method, using the TopFit computer program. The obtained results indicate that the age of calves significantly influenced the pharmacokinetic parameters of paracetamol. A significant increase in the maximum concentration of the drug was noted, as well as in the volume of distribution and metabolic clearance. A significant decrease in mean residence time, biological half-life and area under curve was also observed. The results obtained in the study suggest that the activity of enzymes involved in the metabolism of paracetamol increases with the age of calves. It was therefore concluded that age should obviously be taken into account when studying drug metabolism in calves
The aim of the investigation was the modification of the paracetamol (as a model drug) test for calves. We examined if a precise determination of the pharmacokinetics of paracetamol (indirectly the activity of enzymes catalyzing the reaction of phase II of hepatic biotransformation) was possible using a simplified paracetamol test. The experiment was carried out on 15 healthy calves of BW (Black-and-White) breed. Paracetamol (5 mg/kg bw.) was administered per os on the tenth, twentieth and fourteenth days of the calves’ lives. The concentration of a model drug in plasma was determined by the spectrophotometric method in 10, as well as 3 and 4 samples. Pharmacokinetic parameters were estimated using a non-compartmental method, via the TopFit computer program. The values of pharmacokinetic parameters of paracetamol estimated in “simplified variants” significantly correlated (r = 0.874-0.985) with data obtained in a full test. The highest coefficients of the correlation was observed when the concentration of paracetamol was determined at 3, 4, 6 and 8 hours after the model drug administration. Summing up, it was determined that it is possible to evaluate precisely and indirectly the biotransformation activity in calves (activity of UDP-glucuronyltransferase and sulfonyltransferase) using a simplified variant of paracetasmol test, based on the determination of the concentration of the model drug in 3-4 blood samples.
The aim of the investigation was the pharmacokinetics of paracetamol (as a model drug) in plasma and saliva in calves at different ages. The experiment was carried out on 15 healthy calves of BW (Black-and- -White) breed. Paracetamol (5 mg/kg bw.) was administered per os on the tenth, twentieth and fourteenth days of the calves' lives. The concentration of the model drug in the plasma was determined by the spectrophotometric method. Pharmacokinetic parameters were estimated using a non-compartmental method by means of the TopFit computer program. It was determined that paracetamol concentration in the plasma and saliva was significantly different in many analyzed time points. Insignificant differences were observed in 10-day-old calves after 1.5, 2 and 3 hours after drug administration. In 20 and 40-day-old calves, insignificant changes were observed after 2 and 3 hours after paracetamol administrations. In all examined animals maximal paracetamol concentration was observed after 1 hour following drug administration. The obtained results indicate that saliva is not a good biological fluid for the determination the paracetamol pharmacokinetic parameters in calves.
On the basis of the phenazone test there was assessed the influence of water limitation given to animals on the biotransformable activity of the liver in 9 male calves, Low-land breed, aged from 42 to 45 days. It was found that water limitation had a little effect on the phenazone distribution in the organism (Vd) of animals. In contrast, it was stated a statistically significant decrease of phenazone clearance (T/2) and lowered metabolic values of phenazone clearance (СA) in the experimental group. A diminished capacity of calves’ liver to transform exogenic substances dropped slowly and only at 96 hours after water limitation a decreased volume T/2 and CA were statistically significant.
The aim of this study was a comparison of results of the bile acids test and antipyrine test on calves. The experiment was carried out on 10 healthy calves of Black and White breed. In each subject the antipyrine test was performed on day 10 and 20 after birth. The concentration of bile acids in plasma before feeding (fasting - f SKŻ) and 2 hours after feeding (p SKŻ) were also determined. A correlation analysis was used to compare results of the bile acids test with the antipyrine test. The obtained results indicated that the hepatic biotransformation rate of antipyrine in calves increased significantly with age. The concentrations of fasting bile acids in the plasma of 10 day-old calves and 20 day-old calves were not significantly different. Similar results were obtained in the case of postfeeding bile acids concentrations. In contrast, the concentration of bile acids in plasma 2 hours after feeding was significantly (P<0.01) higher (both in 10 day-old and 20 day-old calves) than the concentration of fasting bile acids. It was determined that fasting and postfeeding concentrations of bile acids in plasma and values of metabolic clearance of antipyrine (C1A) were significantly (P<0.01) correlated.
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