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71.
Cornelia Adlhoch Aleksandra Miteva Anna Zdravkova Tihana Miki Draen Kneevic Sokratis Perdikaris Krzysztof
mietanka Edyta
wito Vilem Kopriva Martin Chudý Luis Jose Romero Gonzlez Ines Moreno Gil Annica Walln Norell Frank Verdonck 《Zoonoses and public health》2019,66(7):874-878
We estimated that more than 11,000 people were exposed to highly pathogenic avian influenza viruses in EU/EEA countries over the outbreak period October 2016–September 2018 by cross‐linking data submitted by Member States to European Food Safety Authority and EMPRES‐i. A stronger framework for collecting human exposure data is required. 相似文献
72.
Małgorzata Brzezińska Paweł Rafalski Teresa Włodarczyk Paweł Szarlip Krzysztof Brzeziński 《Journal of Soils and Sediments》2011,11(7):1142-1154
Purpose
Acetylene (C2H2) is employed for the quantification of important biological processes such as nitrogen fixation, nitrous oxide reduction, ammonium and methane oxidation, and methanogenesis. Although acetylene is not a natural product, the ability of bacteria to grow on C2H2 is a phenomenon common to soils and sediments. Our experiment was designed to study the modification of CO2 production, O2 uptake and microbial biomass (Cmic) in soil in response to the consumption of added acetylene. 相似文献73.
Adam Smoliński Krzysztof Stańczyk Krzysztof Kapusta Natalia Howaniec 《Water, air, and soil pollution》2012,223(9):5745-5758
The main goal of the study was the analysis of the parameters of wastewater generated during the ex situ underground coal gasification (UCG) experiments on lignite from Belchatow, and hard coal from Ziemowit and Bobrek coal mines, simulated in the ex situ reactor. The UCG wastewater may pose a potential threat to the groundwater since it contains high concentrations of inorganic (i.e., ammonia nitrogen, nitrites, chlorides, free and bound cyanides, sulfates and trace elements: As, B, Cr, Zn, Al, Cd, Co, Mn, Cu, Mo, Ni, Pb, Hg, Se, Ti, Fe) and organic (i.e., phenolics, benzene and their alkyl derivatives, and polycyclic aromatic hydrocarbons) contaminants. The principal component analysis and hierarchical clustering analysis enabled to effectively explore the similarities and dissimilarities between the samples generated in lignite and hard coal oxygen gasification process in terms of the amounts and concentrations of particular components. The total amount of wastewater produced in lignite gasification process was higher than the amount generated in hard coal gasification experiments. The lignite gasification wastewater was also characterized by the highest contents of acenaphthene, phenanthrene, anthracene, fluoranthene, and pyrene, whereas hard coal gasification wastewater was characterized by relatively higher concentrations of nitrites, As, Cr, Cu, benzene, toluene, xylene, benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, and benzo(a)pyrene. 相似文献
74.
Barbara Lorkowska-Zawicka Kamil Kamiński Justyna Ciejka Krzysztof Szczubia?ka Magdalena Bia?as Krzysztof Okoń Dariusz Adamek Maria Nowakowska Jacek Jawień Rafa? Olszanecki Ryszard Korbut 《Marine drugs》2014,12(7):3953-3969
This study was performed to evaluate the ability of N-(2-hydroxypropyl)-3-trimethylammonium chitosan chloride (HTCC), the cationically modified chitosan, to form biologically inactive complexes with unfractionated heparin and thereby blocking its anticoagulant activity. Experiments were carried out in rats in vivo and in vitro using the activated partial thromboplastin time (APTT) and prothrombin time (PT) tests for evaluation of heparin anticoagulant activity. For the first time we have found that HTCC effectively neutralizes anticoagulant action of heparin in rat blood in vitro as well as in rats in vivo. The effect of HTCC on suppression of heparin activity is dose-dependent and its efficacy can be comparable to that of protamine-the only agent used in clinic for heparin neutralization. HTCC administered i.v. alone had no direct effect on any of the coagulation tests used. The potential adverse effects of HTCC were further explored using rat experimental model of acute toxicity. When administered i.p. at high doses (250 and 500 mg/kg body weight), HTCC induced some significant dose-dependent structural abnormalities in the liver. However, when HTCC was administered at low doses, comparable to those used for neutralization of anticoagulant effect of heparin, no histopathological abnormalities in liver were observed. 相似文献
75.
Agnieszka Nowak Joanna Kochan Krzysztof Papis Adam Okólski 《Journal of Equine Veterinary Science》2014
The aim of the present study was to determine the vitality and developmental competence of equine oocytes after in vitro maturation (IVM) and vitrified by Rapid-i method. In experiment 1, oocytes after IVM were vitrified using media: EquiPro VitKit (group 1) or medium containing 18% Ficoll, 40% ethylene glycol, and 0.3 M sucrose (group 2). For evaluation of toxicity effect, oocytes were exposed to media without a plug to liquid nitrogen. To evaluate viability, oocytes were stained with fluorescein diacetate and ethidium bromide. In experiment 2, oocytes after IVM and vitrification were activated by 7.5 μM ionomicin in TCM 199 (5 minutes) combined with 2 mM 6-DMAP in TCM 199 with 10% fetal bovine serum (4.5 hours). Survival rate was: 63% in group 1 (n = 54), 55% in group 2 (n = 69), and 73.2% (n = 56) in the control group. After parthenogenetic activation, 10.2% (n = 49) of 2–4 blastomeres were observed. This percentage was lower than in the nonvitrified group: 38.5% (n = 53). 相似文献
76.
Andrzej K. Siwicki Zdzisław Zakęś John C. Fuller Jr Steven Nissen Krzysztof Kazuń Edward Głąbski 《Aquaculture International》2006,14(1-2):153-161
$\upbeta$ -Hydroxy- $\upbeta$ -methyl butyrate (HMB) has been shown to counteract many of the negative effects of intensive fish production methods and results in increased growth and protection against diseases. In the present study, the in vitro and in vivo effect of HMB on the immunocompetence cell activity in tench Tinca tinca (L.) was examined. In the in vitro study pronephric phagocytes and lymphocytes were isolated from the fish and grown in culture medium (RPMI-1640) containing 0, 0.1, 1, 5, 10, 25, 50 or $100\,\upmu$ g HMB cm?3 of medium. The effects of HMB on the respiratory burst activity (RBA), the potential killing activity (PKA) and lymphocyte proliferation stimulated by concanavalin A (ConA) or lipopolysaccharide (LPS) were examined. The in vitro study showed that HMB increased the RBA and PKA of the phagocytes, compared to the medium over that of cells grown without HMB. Lymphocyte proliferation stimulated by ConA and LPS was also increased approximately when HMB was added to the culture medium at concentrations between 10 and $100\,\upmu$ g HMB cm?3. In the in vivo study fish were fed daily with pellets containing HMB at doses 0, 10, 25 and 50 mg kg?1 body weight day?1. The study showed that HMB statistically increased the RBA and PKA and highest activity at 50 mg kg?1 body weight day?1 were observed. Also lymphocyte proliferation stimulated by ConA and LPS were maximally stimulated at dose 50 mg kg?1 body weight day?1. In conclusion, the current study shows that HMB could potentially improve immunocompetence cell activity in tench through increased cell proliferation and functionality. 相似文献
77.
Rovibrational spectroscopy of molecules boasts extremely high precision, but its usefulness relies on the assignment of spectral features to corresponding quantum mechanical transitions. In the case of ortho-H(2)-CO, a weakly bound complex abundant in the interstellar medium (although not yet observed there), the rather complex spectrum has been unexplained for more than a decade. We assigned this spectrum by comparison with a purely ab initio calculation. For most lines, agreement to within 0.01 centimeter(-1) between experiment and theory was achieved. Our results show that the applicability of rovibrational spectroscopy can be extended with the assistance of high-accuracy quantum mechanical computations. 相似文献
78.
Activities of phytase, a pH 6.0 optimum nonspecific phosphomonoesterase and phosphodiesterase assayed toward bis(p-nitrophenyl)phosphate (phosphodiesterase I) and against p-nitrophenylphosphorylcholine (phosphodiesterase II), were partially purified from mycelial extracts of Aspergillus niger AbZ4 cultivated on a molasses medium by a liquid surface fermentation method. After elimination of phosphate from the medium, 7.3- and 3.5-fold enhancements in specific activities of phytase and phosphodiesterase II were observed. Efficacies of mycelial protein fractions in dephosphorylating a wheat-based broiler feed were determined in vitro according to a procedure that simulated digestion in the intestinal tract of poultry. The addition of 0.052 mg of protein from fractions, each of which was high in either pH 6.0 optimum phosphomonoesterase, phosphodiesterase I, phosphodiesterase II, or phytase per gram of a feed sample resulted in the enhancement of phosphorus release by 10, 11, 27, and 88%, respectively. In the presence of an excess of commercial phytase, the addition of the mycelial fraction high in phytase increased the dephosphorylation rate by 56%. The fraction high in phosphodiesterase II enhanced feed dephosphorylation by 8% in the presence of an excess of commercial phytase and commercial acid phosphatase. 相似文献
79.
Design and operation of drainage-subirrigation systems in Poland 总被引:1,自引:0,他引:1
The different techniques used in the design and operation of drainage-subirrigation systems in low-lying riverine areas in Poland are presented. The required groundwater levels used as designing criteria and the applications of the steady state and unsteady state approach to ditch (drain) spacing design in different soil conditions are discussed. The practical application of groundwater level maintenance using the techniques of controlled drainage, subirrigation with a constant water level, and subirrigation with a regulated water level, are shown for three different field sites. 相似文献
80.
Malgorzata Waleron Krzysztof Waleron Joanna Kamasa Wlodzimierz Przewodowski Ewa Lojkowska 《European journal of plant pathology / European Foundation for Plant Pathology》2011,131(2):341-354
The utility of polymorphism analysis was determined for differentiation of the following subspecies of the Gram-positive plant
pathogenic bacterium, Clavibacter michiganensis: C. m. subsp. michiganensis, C. m. subsp. sepedonicus, C. m. subsp. insidiosus C. m. subsp. nebraskensis, and C. m. subsp. tessellarius. Specific primers designed for amplification of the housekeeping genes recA, rpoB, and rpoD generated 827-, 1037-, and 862-bp DNA fragments, respectively. PCR products obtained from 40 C. michiganensis strains were analysed using RFLP with four restriction endonucleases, and those PCR products with specific RFLP patterns
were sequenced. The genotypes discriminated after PCR–RFLP were specific for each subspecies and also allowed for differentiation
of C. m. subsp. michiganensis strains. Sequence analysis of the recA, rpoB, and rpoD gene fragments also distinguished C. michiganensis subspecies and was useful for phylogenetic analysis of all subspecies. For rapid, inexpensive, and effective differentiation
of the five subspecies in this research, we recommend the amplification of recA and/or rpoD gene fragments and digestion of the PCR products with the restriction endonuclease FnuDII. 相似文献