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1.
The aim of this study was to assess the influence of growth on the pharmacokinetics of sodium salicylate (SS) in male turkeys. SS was administered intravenously at a dose of 50 mg/kg. Plasma drug concentrations were assessed by high‐performance liquid chromatography, and pharmacokinetic parameters were calculated by noncompartmental analysis. As the age increased from 6 to 13 weeks (body weight increase from 2.35 to 9.43 kg), median body clearance decreased from 1.34 to 0.87 ml/min/kg. This caused a significant increase in the median mean residence time from 3.42 to 4.44 hr. Elimination phase proved to be biphasic and two elimination half‐lives (T1/2el) were distinguished. Whereas T1/2el1 was found to increase with age by 128%, T1/2el2 represented a later but faster and less age‐dependent phase of elimination (increase by 56% in the respective groups). Volume of distribution decreased with age. These effects may lead to different therapeutic response to SS in turkeys of different age and body weights.  相似文献   
2.
Journal of Soils and Sediments - This study analyzes the variability of sediment loads under variant climate change and land use scenarios in a Carpathian catchment with a dam reservoir. The areas...  相似文献   
3.
Dulling of high-speed steel (HSS) cutting tools after milling five wood species has been analyzed. The wood investigated varied in mineral contamination, high-temperature corrosivity (HTC) and density (D). Experiments performed proved that up to date methods for evaluation of mineral contamination in wood should be improved. A new pipe-like form of mineral contamination particles was evidenced. The correlation between the presence of 3D aggregates of silica in wood and high content of K and Ca in the ash was established. Employing multivariable theoretical simulation method, the combined effect of mineral contamination, HTC and wood density on the tool dullness appeared to be a reasonable explanation of the results obtained.  相似文献   
4.
ABSTRACT

The content of macronutrients in potato tubers arouses interest because of their substantial consumption in the world and significant role in elements' budget in human diet. The research objective has been to evaluate the content of macronutrients in tubers of potatoes grown in different systems of crop production in Poland. In 2012–2014, an experiment was conducted to test potato cultivation in three-crop production systems: conventional, integrated and organic. In each of the six-field crop rotation systems, there were five potato cultivars classified into different earliness groups. The following macronutrients in dry mass of potato tubers were determined: N, P, K, Ca, Mg, Na, S and Cl, and the various ratios between them were calculated. The research carried out proved that potatoes production systems affect the chemical composition of tubers, which is additionally modified by whether condition and genetic features of cultivars. Potato tubers from organic farming contained by about 20% less N than tubers from conventional or integrated systems. Potato tubers from organic production system displayed lower content of Ca and Na in comparison with the conventional and integrated systems. The least of P and S were detected in tubers of the potatoes grown conventionally.  相似文献   
5.
In tissue cultures of Populus maximowiczii Henry, Pb(NO3)2 had a restraining effect on fresh weight increase and anthocyanin content. In ultrastructural research Pb deposits of various size were mainly present in the intercellular spaces, cell walls (mainly in the region of the middle lamella), in the paramural bodies and in the vacuoles. Small deposits of this metal were also observed in the endoplasmic reticulum (ER), dictyosomes and dictyosome derivated vesicles.  相似文献   
6.
The report demonstrates that the induction of apoptosis in peripheral blood granulocytes and lymphocytes of rabbits infected with three non-haemagglutinating RHDV strains (English Rainham, German Frankfurt, and Spanish Asturias) is a crucial determinant of the pathogenesis of rabbit haemorrhagic disease. Apoptosis was measured by flow cytometric detection of caspase activity. These studies demonstrated that the investigated RHDV (rabbit haemorrhagic disease virus) viral strains affected leukocyte apoptosis to varying degrees. Enhanced leukocyte apoptosis was detected between 4 and 36h after infection and was more pronounced in lymphocytes than in granulocytes. The data presented here thus provide a preliminary understanding of the kinetics of apoptosis in leukocytes of rabbits infected with RHDV.  相似文献   
7.
The present study was aimed at determining changes in chosen elements of phagocytosis in rabbits infected with 3 antigenic variants of RHD - Hartmannsdorf, Pv97 and 9905, which differed in haemagglutination ability. The animals were tested for phagocytosis parameters, and the results revealed that the examined strains showed the differences. These variations regarded mainly Pv97 strain, as the intensity of the changes were 5 times stronger in comparison to strain Hartmannsdorf and 9905. As all of the strains examined are signified as antigenic variants, we have stated that this feature does not determine their immunological picture. The results suggest the existence of immunological dissimilarities among strains of the RHD virus, which was revealed for the first time in antigenic variants.  相似文献   
8.
1. Pharmacokinetics of acetylsalicylic acid (ASA) and sodium salicylate (SS) were assessed following single intravenous (i.v.) and oral administration at doses of 50 mg/kg body weight to chickens and turkeys. Plasma drug concentrations were determined using high-performance liquid chromatography with ultraviolet detection and pharmacokinetic variables were calculated using a non-compartmental model.

2. The mean residence time (MRT) of salicylate (SA) after i.v. administration of SS was 6.08 ± 0.59 and 3.32 ± 0.27 h and after oral administration was 6.95 ± 0.72 and 4.55 ± 0.71 h in chickens and turkeys, respectively. The elimination half-life (T 1/2 e) was shorter in turkeys compared with chickens. The value of body clearance (ClB) was higher in turkeys than in chickens, but the apparent volume of distribution (V ss) was similarly low in both species. The bioavailability of SS was complete and the maximal plasma concentration of SA (C max) after oral administration was 96.93 ± 8.06 and 91.76 ± 9.64 µg/ml, respectively, in chickens and turkeys.

3. The MRT of ASA after iv administration was 0.24 ± 0.08 and 0.24 ± 0.02 h and after oral administration was 0.78 ± 0.25 and 0.59 ± 0.13 h, respectively, in chickens and turkeys. In both species, T 1/2 e was very short, ClB and V ss were similar and markedly higher than those of salicylate. The bioavailability of unchanged ASA was low and C max after oral administration was 6.9 ± 3.6 µg/ml in chickens and 8.6 ± 1.3 µg/ml in turkeys.  相似文献   

9.
Chlamydiae are frequently encountered Gram‐negative intracellular eubacteria that can cause clear manifestations or clinically asymptomatic disorders. C. suis and other chlamydia are primarily isolated in cases of reproductive disorders. This study was performed to estimate the impact of Chlamydia suis infection on reproduction in sows by analyzing reproduction rates and breeding parameters. The test was conducted on first generation (F1) pigs from Polish Landrace (PL) × Polish Large White (PLW). Sixty‐four herds were investigated and 500 vaginal swabs were collected. Isolation of DNA was carried out directly from the swabs. All samples were analyzed for Chlamydia suis by real‐time PCR with a locked nucleic acid (LNA)‐containing probe. To analyze the impact of chlamydia infection on reproductive parameters, evaluation questionnaires were used. Reproductive problems were found in 77.3% of the farms tested. The receiver operating characteristic curve indicated that in the farms with 10 up to 120 sows, there were higher reproductive problems with chlamydia infection than in smaller and bigger pig farms. The most common problems were estrus repetition, which was reported by 57.81% of the surveyed farms, and the birth of dead piglets, which was reported by 31.25% of the investigated pig farms. Abortions, which were reported by 28.12% of the surveyed farms, were the least common reproductive disorders.  相似文献   
10.
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