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51.
Schmidt I Renard D Rondeau D Richomme P Popineau Y Axelos MA 《Journal of agricultural and food chemistry》2004,52(19):5995-6001
Chromatographic, chemical, and spectroscopic techniques were used to characterize the physicochemical properties of napin purified by preparative chromatography. The molar extinction coefficient was determined (epsilon = 0.56), and static and dynamic light scattering measurements enabled the average molecular weight (M(w) = 13919), the second virial coefficient (A(2) = 23.95 x 10(-)(5) mol cm(3) g(-)(2)), and the hydrodynamic radius (R(H) = 1.98 nm) to be determined. No conformational changes were observed by fluorescence and circular dichroism measurements in different buffers at pH 3, 4.6, 7, and 12, confirming the high pH stability of this protein. From MALDI-TOF analysis and after enzymatic digestion, it was found that this purified sample, extracted from the rapeseed variety Express, contained mainly isoform 2SS3_BRANA. 相似文献
52.
Comparisons of endocrinological and testis parameters in 18-month-old Ile de France and Romanov rams
M T Hochereau-de Reviers C Perreau C Pisselet I Fontaine C Monet-Kuntz 《Domestic animal endocrinology》1990,7(1):63-73
Endocrinological and testis parameters of adult 18-month-old Ile de France (IF) and Romanov (Ro) rams were compared during sexual season. Testis weights, total volumes of intertubular tissue, and of blood and lymph vessels, total seminiferous tubule length, rete testis flow rate and daily production of germ cells were significantly higher in IF than in Ro rams. These variations originated from differences in Sertoli cell numbers, which were established before puberty. When daily productions of germ cells, of ABP or of RTF were expressed per Sertoli cell, they were higher in Ro than in IF rams. Quality of spermatids, as measured by their cellular size prior to elongation, was lower in Ro than in IF. The number of FSH-binding sites per Sertoli did not differ between the two breeds but FSH plasma levels were higher in Ro than in IF rams. Total numbers of Leydig cells per testis, their individual size or their LH-binding capacity did not differ significantly between the two breeds. However, the ratio of mean testosterone upon mean LH plasma levels were greater in Ro than in IF rams while both breeds had identical LH mean plasma levels. 相似文献
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Studies on vitamin E and selenium deficiency in young pigs. III. Effect on kinetics of erythrocyte production and destruction.
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The effect of vitamin E and/or selenium deficiency on the kinetics of erythrocyte production and destruction has been investigated in swine. The plasma iron turnover rate, 59Fe incorporation into newly formed red cells as well as the 51Cr apparent red cell half-life, were not found to be significantly affected by either vitamin E deficiency, selenium deficiency or deficiency of both, as compared to replete animals. The results of this study suggest that vitamin E is not a limiting factor for normal erythropoiesis in young growing pigs. Erythropoiesis appeared, however, to be slightly decreased in selenium deficient pigs and will need to be further investigated. 相似文献
56.
J C Monier C Fournel M Lapras M Dardenne T Randle C M Fontaine 《American journal of veterinary research》1988,49(1):46-51
A colony of dogs was obtained by the mating of a female German Shepherd Dog crossbred and a male Belgian Shepherd Dog crossbred, both with systemic lupus erythematosus (SLE). The colony also contained 16 dogs representing F1, F2, and F3 generations. Ten colony dogs had circulating antinuclear antibodies, and 5 of the 10 had clinical signs of SLE. Two F3-generation females had signs of severe SLE. Two dogs had antibodies to extractable nuclear antigen, notably 1 dog had antibodies to Smith (Sm) antigen and 1 had antibodies to Sjogren syndrome A (SSA) antigen. Thymulin (serum thymic factor associated with zinc) titers were generally low in the descendants, but fluctuations were detected within the same dog. In vitro response of lymphocytes from these colony dogs to concanavalin A was maximal for lower mitogenic concentrations, compared with response of lymphocytes from 10 healthy dogs. The suppressive lymphocyte activity in 6 autoimmune colony dogs was diminished in comparison with the activity in 5 nonautoimmune colony dogs and 6 healthy dogs. 相似文献
57.
Studies on vitamin E and selenium deficiency in young pigs. II. The hydrogen peroxide hemolysis test and the measure of red cell lipid peroxides as indices of vitamin E and selenium status. 总被引:1,自引:1,他引:0
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The usefulness of the hydrogen peroxide hemolysis test and the measure of red cell lipid peroxides as indices of vitamin E and selenium deficiency in swine has been evaluated. Results indicated that although the hydrogen peroxide hemolysis test may be of some indication of the vitamin E status, it is not a reliable index of vitamin E deficiency in swine, at least on an individual basis. In contrast, the measure of red cell lipid peroxides can be considered a reliable test for vitamin E deficiency in swine. The hydrogen peroxide hemolysis test and the red cell lipid peroxides were not significantly affected by selenium deficiency. 相似文献
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Kirschvink N Marlin D Delvaux F Leemans J Clercx C Sparkes A Gustin P 《Veterinary journal (London, England : 1997)》2005,169(3):385-396
The objective of this study was to describe a standardised and non-invasive method for exhaled breath condensate (EBC) collection in cats and to test whether determination of hydrogen peroxide (H(2)O(2)) in EBC might be used as marker of lower airway inflammation. The technique of barometric whole body plethysmography for cats was combined with a system to condense the effluent air from the plethysmograph, allowing simultaneous EBC collection and respiratory pattern measurement. H(2)O(2) was determined spectrophotometrically. Eighteen experimental cats were used to investigate the impact on EBC volume and EBC H(2)O(2) of plethysmograph ventilation rate, collection duration, sample stability, within-day and day-to-day variability. After determination of a standardised EBC collection procedure, correlation analyses between EBC H(2)O(2) and bronchoalveolar lavage (BAL) cytology of healthy and allergen-challenged Ascaris suum (AS)-sensitised cats were performed. A significant and positive correlation between EBC H(2)O(2) and bronchoalveolar lavage (BAL) neutrophil% was found in healthy cats (P < 0.001, r = 0.55), whereas in AS-sensitised cats, correlation with BAL eosinophil% was significant (P < 0.005, r = 0.61). H(2)O(2) was increased after an allergen challenge in AS-sensitised cats (n = 6, 0.56+/-0.12 versus 1.08+/-0.35 micromol/L, P < 0.05). This study proposes a non-invasive, well tolerated and repeatable method of EBC collection for cats and suggests that EBC H(2)O(2) might be used as non-invasive biomarker for monitoring lower airway inflammation. 相似文献
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