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31.
The study evaluated the pharmacokinetics of tramadol and its major metabolites O-desmethyltramadol (M1), N-desmethyltramadol (M2) and N-O didesmethyltramadol (M5) following a single oral administration of a sustained release (SR) 100mg tablet to dogs. Plasma tramadol concentration was greater than the limit of quantification (LOQ) in three dogs, M1 was quantified only in one dog while M2 and M5 were quantified in all of the dogs. The median values of C(max) (maximum plasma concentration), T(max) (time to maximum plasma concentration) and T(1/2) (half-life) for tramadol were 0.04 (0.17-0.02)mirog mL(-1), 3 (4-2) and 1.88 (2.211-1.435)h, respectively. M5 showed median values of C(max), T(max) and T(1/2) of 0.1 (0.19-0.09)microg mL(-1), 2 (3-1) and 4.230 (6.583-1.847)h, respectively. M2 showed median values of C(max), T(max) and T(1/2) of 0.22 (0.330-0.080)microg mL(-1), 4 (7-3) and 4.487 (6.395-1.563)h, respectively. The findings suggest that the SR formulation of tramadol may not have suitable pharmacokinetic characteristics to be administered once-a-day as an effective and safe treatment for pain in the dog.  相似文献   
32.
Cultivating resistant varieties of potato is the most effective and environmentally sound method of protecting potato crops against pests and diseases. Potato cyst nematodes (PCN) are major nematode pests causing severe constraints in potato production worldwide. There are five pathotypes of Globodrea rostochiensis (Ro1–Ro5) and three of G. pallida Pa1–Pa3. Cultivation of potato varieties with broad nematode resistance may influence the growth of the wide spectrum of PCN pathotypes, but there is limited availability of such varieties on the market. The use of molecular markers allows for the effective selection of resistant genotypes at early stages of breeding. However, the impact of early selection for nematode resistance on the agronomic value of the final selected clones is a cause of concern for potato breeders. This study investigates the relationships between the presence of the combined resistance genes H1, Gro1-4 and GpaVvrn, which confer resistance to the nematodes, and certain agricultural traits. Clones with broad nematode resistance conferred by the genes H1, Gro1-4 and GpaVvrn presented yields and tuber morphology traits similar to those of the clones without identified resistance genes.  相似文献   
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Tomato black ring virus (TBRV) is a worldwide-distributed RNA virus infecting a wide range of different host plants, including crop species, trees, shrubs, and weeds. Here, we investigated the molecular evolution of TBRV and its adaptability to different plant species. The TBRV-Pi isolate was used to generate five independent evolution lineages serially passaged in either quinoa, tobacco, or tomato plants. After 15 passages, the genetic variability present in all the lineages was characterized for the movement (MP) and coat (CP) coding cistrons. We addressed two main questions: to what extent does the amount of genetic variability in the TBRV genome depend on the host species, and are there host species-specific adaptive mutations? Overall, 201 different nucleotide substitutions emerged during the evolution experiment, with some of them appearing multiple times in different lineages; two of them (one in CP and one in MP) were unique for a particular host plant. We have shown that the degree of genetic differentiation depends on the host species in which the virus evolved, and that positive selection is operating upon certain residues, particularly in CP. Moreover, we have characterized new types of defective RNAs that arose during the TBRV-Pi evolution in tobacco. Furthermore, this is the first report of a defective RNA from the RNA2 of TBRV.  相似文献   
35.
The effect of alkaline deposition produced by the ‘Kujawy’ cement and lime factory in Bielawy, Poland, on the mites in young Scots pine forests (plants class Vaccinio-Piceetea) was investigated. The concentration of calcium in tree bark and epiphytes, which provide a habitat for mites, as well as in soil was the lowest in the control plot, and increased in the direction of the factory. A high concentration of calcium correlated with an absence of lichens from tree bark, but a medium concentration was associated with a higher species number of lichens. The density of arboreal mites and the species number of Oribatida were the highest in the control plot and decreased when getting closer to the factory. In a highly contaminated plot, the density of soil mites was lower, while in a medium contaminated plot it was higher than in the control plot. In the contaminated plots, the species number of soil Oribatida and Gamasida was lower than in the control plot, except in a least contaminated plot where the number of gamasid species was higher than in the control plot. Some species were sensitive to calcium, others were sensitive to a high concentration but tolerated medium and small concentrations of this element, and yet others tolerated calcium. The arboreal mites reacted to alkaline deposition more distinctly than soil mites.  相似文献   
36.
Journal of Plant Diseases and Protection - Weed species within arable farming systems act as a source of food and provide habitat for various taxa at higher trophic levels. Using field experiments...  相似文献   
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Context

Black poplar (Populus nigra L.) is an alluvial forest tree species whose genetic pool is decreasing in Europe. Poplar trees produce short-lived seeds that do not store well.

Aim

The feasibility of seed storage in conventional and cryogenic conditions after their desiccation from water content (WC) of 0.15 to 0.07 g H2O g?1 dry mass (g g?1) was investigated.

Methods

Seed germinability was evaluated (seeds with a radicle and green cotyledons were counted) after storage of seeds for a period of 3 to 24 months at different temperatures: 20°, 10°, 3°, ?3°, ?10°, ?20° or ?196°C.

Results

Seeds desiccated to a 0.07 g g?1 WC can be stored successfully at ?10 °C and ?20 °C for at least 2 years. A significant decrease in germination was observed only after 12 months of seed storage (WC 0.15 g g?1) at temperatures above 0 °C. We demonstrated that both fresh (0.15 g g?1 WC) and desiccated (0.07 g g?1 WC) seeds can be preserved at ?196 °C for at least 2 years.

Conclusions

Seed storage temperature and time of storage were statistically significant factors affecting seed storability. The presented data provide a foundation for the successful gene banking of P. nigra seeds.  相似文献   
39.
We report the humanization of the glycosylation pathway in the yeast Pichia pastoris to secrete a human glycoprotein with uniform complex N-glycosylation. The process involved eliminating endogenous yeast glycosylation pathways, while properly localizing five active eukaryotic proteins, including mannosidases I and II, N-acetylglucosaminyl transferases I and II, and uridine 5'-diphosphate (UDP)-N-acetylglucosamine transporter. Targeted localization of the enzymes enabled the generation of a synthetic in vivo glycosylation pathway, which produced the complex human N-glycan N-acetylglucosamine2-mannose3-N-acetylglucosamine2 (GlcNAc2Man3GlcNAc2). The ability to generate human glycoproteins with homogeneous N-glycan structures in a fungal host is a step toward producing therapeutic glycoproteins and could become a tool for elucidating the structure-function relation of glycoproteins.  相似文献   
40.
The results of most studies show the beneficial effect of milking automation on production parameters of dairy cows, but its effect on fertility traits is debatable. Therefore, a study was undertaken to predict cow fertility – services per conception (SC) and calving interval (CI) – based on automatic milking system (AMS) data collected in the periparturient period subdivided into the second and first week before calving, 1–4, 5–7, 8–14, 15–21 and 22–28 days of lactation. SC and CI were predicted using daily indicators such as concentrate intake, number of milkings, cow box time, milking time, milking speed, colostrum and milk yield, composition, temperature and electrical conductivity. The study material was derived from the AMS management system and from the SYMLEK milk recording system. The analysis covered data for 16,329 milkings of 398 Polish Holstein-Friesian (PHF) cows, which were used in three AMS herds. The collected numerical data were statistically analysed by correlation analysis in parallel with decision tree technique (SAS statistical package). The present study showed that due to the low, mostly non-significant coefficients of correlation between AMS data collected between 2 weeks before and 4 weeks after calving, it is not possible to predict cow fertility based on single traits. It has been established that the decision tree method may help breeders, already during the postcalving period, to choose the level of factors associated with AMS milking, which will ensure good fertility of cows in a herd. The most favourable number of services per conception is to be expected from cows that were milked <1.6 times per day from 1 to 4 days of lactation and electrical conductivity of their colostrum did not exceed 69 mS during that time. In turn, shortest CI (366 days) will be characteristic of the cows whose average daily colostrum yield did not exceed 20.2 kg and their daily concentrate intake from 8 to 14 days of lactation was at least 5.0 kg.  相似文献   
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