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81.
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
82.
Kowalska A Zakęś Z Siwicki AK Jankowska B Jarmołowicz S Demska-Zakęś K 《Fish physiology and biochemistry》2012,38(2):375-388
The aim of the study was to determine the impact of applying different proportions of linseed (LO) and sunflower (SFO) oils
in pikeperch diets on growth, histological changes in the liver, immunological and blood chemical parameters. The fish were
fed isoenergetic and isoprotein feeds containing SFO (group 100SFO) or LO (group 100LO) in quantities of 67 g kg/feed, and
a mixture of oils: 47 g SFO and 20 g LO kg/feed (group 70SFO/30LO) and 20 g SFO and 47 g LO kg/feed (group 30SFO/70LO). Dietary
ratios of polyunsaturated fatty acids from the n-3 and n-6 series (n3/n6 index) were 0.36–2.15. Pikeperch were reared for
56 days in three replicates for each dietary treatment. Various dietary oils and ratios of n3/n6 did not impact fish growth,
feed conversion ratio, viscerosomatic and hepatosomatic index, and size of the hepatocytes. Feeding the fish high quantities
of LO and SO oils (groups 100LO and 100SFO) reduced the immunological response of the phagocytes and lymphocytes in the fish.
Moreover, this resulted in significant differences among groups in the quantity of linolenic and linoleic acid in whole fish
bodies, viscera, fillets, and livers. Various quantities of vegetable oils in the fish diets did not impact the quantity of
arachidonic, eicosapentaenoic and docosahexaenoic acid in the fillets and livers. The immunological index and low quantities
of linoleic acid in the fillets obtained in group 30SFO/70LO indicate that the n3/n6 dietary ratio of 1.35 was the most advantageous
for feeding juvenile pikeperch feeds with vegetable oils. 相似文献
83.
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
84.
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
85.
Serum concentrations of allergen‐specific IgE in horses with equine recurrent airway obstruction and healthy controls assessed by ELISA 下载免费PDF全文
86.
Kuźmińska-Bajor M Kuczkowski M Grzymajło K Wojciech Ł Sabat M Kisiela D Wieliczko A Ugorski M 《Veterinary microbiology》2012,158(1-2):205-210
To investigate the role of non-hemagglutinating type 1 fimbriae in the pathogenesis of Salmonella Gallinarum, the isogenic mutant elaborating type 1 fimbriae with mannose-sensitive (MS) variant of the FimH adhesin from Salmonella Enteritidis and the mutant strain with no FimH expression were constructed. Their binding to chicken leukocytes in vitro and invasiveness in 1-day-old chicks were studied. Our results demonstrated that S. Gallinarum type 1 fimbriae with an endogenous variant of the FimH adhesin mediated mannose-resistant (MR) binding to avian leukocytes and did not bind to human epithelial cells. However, after allelic replacement of the FimH, mutated fimbriae with S. Enteritidis variant of the FimH adhesin bound to both cell types in a mannose-dependent manner. In chick model, S. Gallinarum expressing wild-type FimH variant colonized cecal tonsils and bursa of Fabricius more effectively and invaded the spleen and liver in greater numbers than S. Gallinarum fimH knockout strain or mutant expressing MS FimH variant from S. Enteritidis. The invasive potential of the latter was greatly reduced in chicks since no viable bacteria expressing MS variant of the adhesin could be recovered from intestinal lymphoid tissues or liver over a 6 days course of infection. Together, these results demonstrate that the S. Gallinarum type 1 fimbriae with the endogenous MR variant of the FimH protein increase systemic dissemination of S. Gallinarum and colonization of internal organs in chicks indicating the importance of these adhesive structures in the virulence of S. Gallinarum. 相似文献
87.
88.
Krzysztof Gondek Michał Kopeć Tomasz Mróz 《Communications in Soil Science and Plant Analysis》2018,49(11):1257-1265
Biochar used in this study was prepared from wheat straw and enriched with 10% solutions of chemically pure salts: ammonium sulfate [(NH4)2SO4] and magnesium sulfate (MgSO4 7H2O). The aim of this study was to determine the growth response of Perennial ryegrass L. as well as identify changes in chemical and biological properties of sandy soil after the application of biochar. A significant increase in the amount of Perennial ryegrass L. biomass was determined after amending the soil with unenriched biochar and biochar enriched with (NH4)2SO4. The highest immobilization of available forms of Mg was observed for biochar enriched with (NH4)2SO4. The highest dehydrogenase activity was determined in the soil with biochar enriched with MgSO4 7H2O. 相似文献
89.
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
90.
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