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41.
The efficiency of sheep is dependent on their health and well-being. The blood markers can be critical for improving of the
physiological, nutritional and pathological status of sheep organism. The aim of this study was to test the hypotheses that
the red and white blood cells and copper (Cu) and zinc (Zn) plasma contents are impacted by altitude and season. The ewes
were kept at three farms. Blood samples were divided according to factors of altitude (550 m, 800 m, 950 m above sea level),
season (spring, fall) and year. The lowest haemoglobin concentration and value of haematocrit were detected at the altitude
of 550 m (66.95 g L−1, 0.36 L L−1) and the highest at the altitude of 950 m (117.96 g L−1, 0.39 L L−1) (P < 0.001). Spring values of haemoglobin and haematocrit were lower than fall values. The highest count of leucocytes was recorded
at the altitude 950 m (9.57 G L−1), higher counts were contained in spring (P < 0.001). The lowest percentage of eosinophiles was found at the altitude of 800 m (5.81%) and the highest at the altitude
of 550 m (9.26%) (P < 0.01). Phagocytose activities were the highest at the altitude of 950 m (95.07%) and the lowest at the altitude of 550
m (85.04%) (P < 0.001). Phagocytose activities were higher in fall than in spring. The highest Cu concentration was found at the altitude
of 550 m and the lowest at the altitude of 800 m (17.04 μmol L−1 vs. 14.37 μmol L−1). Zn levels were higher at altitudes of 950 m and 800 m than at the altitude of 550 m (17.81 μmol L−1, 17.00 μmol L−1 vs. 14.77 μmol L−1). We concluded that hematological markers and trace mineral content in grazed sheep may be impacted by altitude and season. 相似文献
42.
Electrochemical based immunosensors for the detection of boldenone and methylboldenone in bovine urine were described in this paper. The immunosensors were fabricated by immobilizing boldenone-bovine serum albumin conjugate on the surface of screen-printed electrodes (SPEs), and followed by the competition between the free analyte and coating conjugate with corresponding antibodies. The use of anti-species IgG-horseradish peroxidase conjugate determined the degree of competition. The electrochemical technique chosen was chronoamperometry, performed at a potential of +100 mV whereby the product of the catalysis of 3,3′,5,5′-tetramethylbenzidine undergoes reduction produced by the enzyme label. The limits of detection of assay were 30.9 ± 4.3 pg ml−1 for boldenone and 120.2 ± 8.2 pg ml−1 for methylboldenone, respectively. Results of repeated analysis of each androgen carried out using three different batches of electrodes indicate suitable repeatability (EC50 = 1.0 ± 0.3 ng ml−1 (n = 3, N = 3), R2 = 0.969, R.S.D. = 9.6% for boldenone and 1.5 ± 0.3 ng ml−1, 0.971, 10.5% for methylboldenone, respectively). Urine samples were determined directly after a single dilution step, omitting extraction and hydrolysis. This method offers the advantage to pick up both boldenone and its major metabolites in an efficient manner due to the high cross-reactivity pattern of α-boldenone with this antibody. The concentration of methylboldenone in urine detected by developed methods does indicate methylboldenone administration to heifers. Gas chromatography coupled to mass spectrometry analysis was performed to quantitate the individual metabolites present in urine samples, and results were validated with both ELISA and immunosensor data. 相似文献
43.
The hydrogen isotope-effect that occurs in vitro during myo-inositol 1-phosphate synthase-catalyzed conversion of d-[5-3H]glucose 6-phosphate into myo-[2-3H]inositol 1-phosphate has been used to compare the functional role of the nucleotide sugar oxidation-pathway with that of the myo-inositol oxidation-pathway in germinating lily pollen. Results reveal a significant difference between the 3H/14C ratios of glucosyl and galactosyluronic residues from pectinase-amyloglucosidase hydrolyzates of the 70 % ethanol-insoluble fraction of d-[5-3H, 1-14-C]glucose-labeled, germinating lily pollen. This isotope effect at C-5 of d-glucose that occurred during its conversion into d-galactosyluronic residues of pectic substance is not explained by loss of 3H when UDP-d-[5-3H, 1-14C]glucose is oxidized by UDP-d-glucose dehydrogenase from germinating lily pollen. The evidence obtained from this study favors a functional role for the myo-inositol oxidation pathway during in vivo conversion of glucose into galactosyluronic residues of pectin in germinating lily pollen. 相似文献
44.
Aleš Lebeda Miloslav Kitner Marta Dziechciarková Ivana Doležalová Eva Křístková Pim Lindhout 《Biochemical Systematics and Ecology》2009
Prickly lettuce (Lactuca serriola) is world-wide distributed and very variable species generally considered as a progenitor of the cultivated lettuce (Lactuca sativa). Altogether, 50 populations of L. serriola were characterized by means of amplified fragment length polymorphism (AFLP) and by isozyme analysis. Relationships among individuals and populations were examined by applying the unweighted pair-group method with the arithmetic averages (UPGMA) clustering algorithm, principal coordinate analysis (PCA) and the Nei's gene diversity index. The studied set of populations split into three main groups based on the AFLP polymorphism analysis. The first group contained L. sativa (control). The second group comprised two L. serriola accessions; one of them was identified as L. serriola f. integrifolia and the other as a mixture of two L. serriola forms. The largest and the most diverse third group contained the remaining L. serriola accessions. The population clustering corresponded approximately to their geographical distribution in Europe. At least five distinct geographic groups were recognised: 1) Northern European; 2) Slovenian; 3) very heterogeneous Central and Western European (mostly north of the Alps); 4) Mediterranean; 5) prevalence of L. serriola f. integrifolia, mostly comprising accessions from the United Kingdom and the Netherlands. This study showed that accessions originating in various eco-geographical conditions of Europe differ significantly in their genetic and protein polymorphism, as well as in morphology. Some European L. serriola populations (e.g. from Scandinavia and United Kingdom/British Isles/) seems to be isolated and homogeneous; in contrast, populations occurring in Central Europe are very diverse and genetically overlapping. 相似文献
45.
Takeshi Furuhashi Ivan Miksik Miloslav Smrz Bettina Germann Dashnor Nebija Bodo Lachmann Christian Noe 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2010,155(2):195-200
Acidic macromolecules, as a nucleation factor for mollusc shell formation, are a major focus of research. It remains unclear, however, whether acidic macromolecules are present only in calcified shell organic matrices, and which acidic macromolecules are crucial for the nucleation process by binding to chitin as structural components. To clarify these questions, we applied 2D gel electrophoresis and amino acid analysis to soluble shell organic matrices from nacre shell, non-nacre aragonitic shell and non-calcified squid shells. The 2D gel electrophoresis results showed that the acidity of soluble proteins differs even between nacre shells, and some nacre (Haliotis gigantea) showed a basic protein migration pattern. Non-calcified shells also contained some moderately acidic proteins. The results did not support the correlation between the acidity of soluble shell proteins and shell structure. 相似文献
46.
Nitrous acid deamination of 2-amino-1,6-anhydro-2-deoxy-β-D-glucopyranose (1) in the presence of weakly acidic, cation-exchange resin gave 1,6:2,3-dianhydro-β-D-mannopyranose (3) and 2,6-anhydro-D-mannose (6), characterized, respectively, as the 4-acetate of 3 and the per-O-acetylated reduction product of 6, namely 2,3,4,6- tetra-O-acetyl-1,5-anhydro-D-mannitol, obtained in the ratio of 7:13. Comparative deaminatior of the 4-O-benzyl derivative of 1 led to similar qualitative results. Deamination of 3-amino-1,6-anhydro-3-deoxy-β-D-glucopyranose gave 1,6:2,3- and 1,6:3,4-dianhydro-β-D-allopyranose (13 and 16), characterized as the corresponding acetates, obtained in the ratio of 31:69, as well as the corresponding p-toluenesulfonates. Deamination of 4-amino-1,6-anhydro-4-deoxy-β-D-glucopyranose and of its 2-O-benzyl derivative gave the corresponding 1,6:3,4-D-galacto dianhydrides as the only detectable products. 2,5-Anhydro-D-glucose, characterized as the 1,3,4,6-tetra-O- acetyl derivative of the corresponding anhydropolyol, was obtained in 39% yield from the same deamination reaction performed on 2-amino-1,6-anhydro-2-deoxy-β-D- mannopyranose (24). In 90% acetic acid, the nitrous acid deamination of 24, followed by per-O-acetylation, gave only 1,3-4-tri-O-acetyl-2,5-anhydro-α-D-glucoseptanose. In the case of 1,6-anhydro-3,4-dideoxy-3,4-epimino-β-D-altropyranose, only the corresponding glycosene was formed, namely, 1,6-anhydro-3,4-dideoxy-β-D-threo--hex-3-enopyranose. 相似文献
47.
Nikolaos Robakis Miloslav Boublik 《Biochemical and biophysical research communications》1981,103(4):1401-1408
The effect of protein moiety on the conformation of 16S and 23S RNA of the ribosome has been studied by circular dichroic spectroscopy. Both rRNAs possess a comparable net content of ordered secondary structure which remains unchanged after association with ribosomal proteins into “core” particles or into complete 30S and 50S subunits, respectively. However, differences found in the stability and the cooperativity of melting of free and protein-associated rRNAs imply protein-caused variations in the distribution of the intramolecular hairpin stems and loops and/or changes in long range tertiary interactions which appear to be different for both rRNAs. While 23S RNA is maximally stabilized on the large subunit by the full set of proteins, 16S RNA on the complete small subunit shows lower stability but higher cooperativity in melting. 相似文献
48.
49.
Young rats deprived of solid food will survive on mother's milk only for about seven weeks but their development will become arrested completely. As soon as they receive solid food their development recommences immediately at the same rate as that of control infant rats. However, young rats still continue to take maternal milk for about one more week, which is the result of the gradual extinction of the sucking reflex depending the maturity of the young rats. 相似文献
50.