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61.
62.
Jan Suszka Beata P. Plitta Marcin Michalak Barbara Bujarska-Borkowska Tadeusz Tylkowski Paweł Chmielarz 《Annals of Forest Science》2014,71(5):543-549
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63.
R. Steppa K. Szkudelska J. Wójtowski M. Stanisz M. Szumacher‐Strabel G. Czyżak‐Runowska A. Cieślak M. Markiewicz‐Kęszycka M. Pietrzak 《Journal of animal physiology and animal nutrition》2014,98(5):914-920
The effect of two diets enriched with unsaturated fatty acids – one containing the addition of dried distillers grains with solubles (DGS) and the other the addition of false flax – Camelina sativa cake (CS) – on some metabolic parameters and hormone concentration in growing lambs was determined in this experiment. A total of 21 ram lambs of the Polish Whiteheaded mutton sheep were divided into three groups (the control, receiving DGS and CS). The diets were administered to animals for 6 weeks. During the experiment, peripheral blood was collected. Glucose (GL), total cholesterol (CH), triglycerides (TG), free fatty acids (FFA), insulin (IN), leptin (LE), triiodothyronine (T3) and thyroxine (T4) were assayed in serum. The age‐dependent reduction in CH and TG limited by both experimental diets were observed. A significant increase in FFA concentration was observed in samples collected in the last, that is, third, time period. This was most probably caused by a 12‐h pre‐slaughter fasting period. A significantly lower dynamic of FFA increase in that experimental period was found in animals receiving the experimental feed. Insulin concentration in DGS‐receiving lambs was increased, in contrast to the CS‐receiving lambs, in which it was lower when compared to the control. LE concentration was decreased by both experimental diets, more markedly in the DGS‐receiving animals. No differences between the experimental groups and the control were observed in T3 and T4 concentrations. The effect of 12‐h pre‐slaughter fasting was statistically highly significant for the levels of examined blood markers and hormones, except for TG and IN in the group of lambs receiving the experimental diet with CS. 相似文献
64.
Hamilton SR Bobrowicz P Bobrowicz B Davidson RC Li H Mitchell T Nett JH Rausch S Stadheim TA Wischnewski H Wildt S Gerngross TU 《Science (New York, N.Y.)》2003,301(5637):1244-1246
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
65.
Piotr Kliś Anna Sawa Dariusz Piwczyński Beata Sitkowska Mariusz Bogucki 《Reproduction in domestic animals》2021,56(9):1227-1234
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
66.
Irene Sartini Beata ebkowska‐Wieruszewska Andrzej Lisowski Amnart Poapolathep Barbara Cuniberti Mario Giorgi 《Journal of veterinary pharmacology and therapeutics》2021,44(1):28-35
Acetaminophen (paracetamol) is used in dogs to manage fever and mild pain. The aim of this study was to assess the pharmacokinetics of acetaminophen in both fed and fasted Labrador Retrievers after a single intravenous and oral administration (20 mg/kg). Six healthy dogs underwent three treatments in a randomized block study (a, n = 2; b, n = 2; c, n = 2). In phase one, group a received acetaminophen intravenously, group b and c orally after being fasted and fed, respectively. In phase two and three, groups were swapped, and the experiment was repeated. At the end of the trial, each dog received the same treatment. Acetaminophen plasma concentrations were detected using a validated HPLC‐UV method. The pharmacokinetic analysis was performed using a noncompartmental model. Clearance, volume at steady state and half‐life of acetaminophen in Labrador Retrievers were 0.42 L/kg hr, 0.87 L/kg and 1.35 hr, respectively. No significant statistical differences were found between fasted and fed dogs regarding maximum plasma concentration, time at maximum concentration and bioavailability as measured by the AUC. Feeding does not significantly affect the acetaminophen oral pharmacokinetics. 相似文献
67.
Szczepanik M Obara R Szumny A Gabryś B Halarewicz-Pacan A Nawrot J Wawrzeńczyk C 《Journal of agricultural and food chemistry》2005,53(15):5905-5910
Starting from precocenes I and II, four of their derivatives with a lactone moiety were obtained. The compounds have been assessed as antifeedants against several diverse insect species including the storage pests the confused flour beetle (Tribolium confusum Duv., larvae and adults), the granary weevil beetle (Sitophilus granarius L., adults), and the khapra beetle (Trogoderma granarium Ev., larvae) and against the herbivorous pest insects Colorado potato beetle (Leptinotarsa decemlineata Say, adults and larvae) and aphids (Myzus persicae Sulz.). Precocenes, especially precocene II, showed a very strong antifeedant effect against all storage pests and aphids. The introduction of a lactone moiety caused a decrease in antifeedant activity against these species. Both precocenes were moderately active against L. decemlineata adults. The best antifeedants to this species were precocene derivatives, especially iodolactones. The introduction of iodine into a molecule had a great effect on the antifeedant activity of those compounds. 相似文献
68.
In 1999, we published a report on how an introduction of 20 males into a severely inbred and isolated population of adders (Vipera berus) halted its decline towards extinction, induced a profound change in population genetic variability, resulted in a dramatic increase in offspring viability and thus in a rapid increase in numbers. Since the publication of our paper we have received numerous inquiries as to whether we have continued to monitor this population, as this is the case we herein present population demographic data gathered between 1981 and 2003. The population has continued to increase in numbers and in 2003, we collected 39 adult male adders, more than at any time over the 23-year study. Our continued work, hence, lends strong support to the importance of novel genes in enhancing the viability of inbred populations and supports the importance of preserving genetic variability in order to maintain viable wild populations. 相似文献
69.
Tadeusz Adamski Jerzy Chełkowski Zygmunt Kaczmarek Maria Surma Halina Wiśniewska 《Euphytica》1997,93(2):169-172
Auto- and alloplasmic doubled haploid (DH) lines of barley were examined for susceptibility to Fusarium culmorum (W.G.Sm.) Sacc. (isolate KF350) seedling blight. Inoculated kernels were incubated at 20 °C in a chamber saturated to 100% RH a with 12/12 h dark/light cycle. Germination capacity, disease score on a 5-degree scale and root length were evaluated. The data were analysed statistically using three-factor analysis of variance. It was observed that the infection score of roots of DH lines with H. bulbosum cytoplasm was higher than that of their autoplasmic analogues. Length of infected seedling roots expressed as per cent of the control root length ranged from 81 to 56% in autoplasmic DH lines and from 60 to 48% in alloplasmic lines. These differences were statistically significant (at P = 0.01). It was evident, that H. bulbosum cytoplasm increase susceptibility of barley genotypes to Fusarium seedling blight. 相似文献
70.