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811.
T Cichocki D Heck L Jarczyk E Rokita A Strza?kowski M Sych 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》1988,26(4):187-192
Inorganic deposits in the wall of human and animal arteries and in experimental tumor (Morris hepatoma 7777) were examined using proton induced X-ray emission (PIXE) and PIXE in combination with proton microprobe (micro-PIXE) techniques. The sections adjacent to the irradiated ones part were submitted to histological investigations and one part of the material was additionally investigated by infrared (IR) spectroscopy. For identification of mineral deposits, the micro-PIXE method appeared the most sensitive. The mineral deposits were detected in the artery samples, even in those without visible morphological changes, as well as in tumor samples. The deposites showed different localization and composition, depending on age and type of vessel. There were also differences between human and animal arteries. IR spectroscopy revealed the presence of carbonate apatite within the artery samples from old individuals. Matching of histological observations with data obtained by micro-PIXE method allows a better correlation of morphological and analytical results. 相似文献
812.
Edward Oczeretko Agnieszka Kitlas Jolanta Swiatecka Tadeusz Laudański 《Theoretical biology forum》2004,97(3):499-504
The fractal dimension D may be calculated in many ways, since its strict definition, the Hausdorff definition is too complicated for practical estimation. In this paper we perform a comparative study often methods of fractal analysis of time series. In Benoit, a commercial program for fractal analysis, five methods of computing fractal dimension of time series (rescaled range analysis, power spectral analysis, roughness-length, variogram methods and wavelet method) are available. We have implemented some other algorithms for calculating D: Higuchi's fractal dimension, relative dispersion analysis, running fractal dimension, method based on mathematical morphology and method based on intensity differences. For biomedical signals results obtained by means of different algorithms are different, but consistent. 相似文献
813.
T. Cichocki S. Divoux B. Gonsior M. Höfert L. Jarczyk B. Raith E. Rokita A. Strzalkowski M. Sych 《Histochemistry and cell biology》1990,94(2):171-177
Summary The proton induced X-ray emission method in combination with a proton microprobe was applied to study the intramembranaceous
ossification. As material sections of mouse embryo skulls from the 17th and 19th day of gestation were used. The morphology
of the sample was examined by routine histochemical procedure performed on the sections adjacent to that irradiated by the
proton microprobe. The measurements were made in line scan and raster scan mode. The concentrations of P, S, Cl, K, Ca, Fe
and Zn were determined at each irradiated point. The average element concentrations were calculated for four parts of each
section (bone, cartilage, mesenchymal tissue close to the bone and mesenchymal tissue in other places). The distributions
of Ca and P (less markedly than Ca) concentrations almost exclusively correlate with localization of the bone while S, Cl
and K concentrations show preference to the cartilage. The amount of inorganic material in flat bones of the 17-day embryo
amounts to 14% of the dry mass. The material is characterized by a Ca/P ratio of bout 1.6 In the embryo 2 days older the amount
of the inorganic phase is practically the same (15%) while the Ca/P ratio approaches 2. This suggests the presence of the
precursor phase in the flat bone calcification. It is possible that octacalcium phosphate (Ca/P ratio equals to 1.72) is formed
at the onset of the flat bone mineralization which transforms rapidly (in 2 days) to a more stable mineral (defective hydroxyapatite). 相似文献
814.
Tadeusz Antczak Julita Mrowiec-Białoń Stanisław Bielecki Andrzej B. Jarzębski Janusz J. Malinowski Andrzej I. Lachowski Edward Galas 《Biotechnology Techniques》1997,11(1):9-11
The lipase ofMucor javanicus (nowM. circinelloides) entrapped in silica matrix by the sol-gel method esterified primary and secondary alcohols with conversions ranging from
30 to 35% and 10 to 15%, respectively. Loss in activity of the preparations after incubation at 100°C for 1 h with petroleum
ether, dodecane, 1-heptanol or oleyl alcohol was about half of that observed for the native lipase. 相似文献
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816.
Summary About 25% of total pyruvate kinase activity in human skeletal muscle is associated with the ribonucleoprotein complexes soluble in salt solutions of high ionic strength. These complexes, called form MB, crystallize readily from 48% saturated ammonium sulfate at pH 5.6.Crystalline preparations represent a heterogenous population of ribonucleoprotein complexes displaying a graduated activity and a variable RNA content. Free protein was not detected in the preparations.Fractionation of crystalline complexes in salt solutions of varying ionic strength and pH, followed by gel filtration on Sephadex G-200 led to the separation of two nucleoprotein fractions with very high specific activity. Fractions containing 30% RNA and 85% RNA respectively revealed a specific activity of 660–670 U/mg protein at 25°C.Pyruvate kinase form MA was extracted from muscle homogenate with distilled water, purified to homogeneity and crystallized. It contained less than 0.2% RNA and had a specific activity of 270 U/mg. Active ribonucleoprotein complexes gave in double immunodiffusion test the precipitation bands with the anti-MA sera at the same protein concentration of both antigens, MB and MA.Pyruvate kinase MB with high activity is sensitive to treatment with RNase. Digestion with RNase for 10 min at 25°C diminished the initial specific activity to about one third. Similar residual activity was found in crystalline ribonucleo protein complexes with low RNA content (3.5–20% RNA) which are resistant to further inactivation by RNase.These results implicate the enhancement and control of pyruvate kinase activity by RNA bound to the enzyme.This work was supported by a grant from the Biochemical and Biophysical Committee of Polish Academy of Sciences. 相似文献
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820.
Bonda-Ostaszewska Elżbieta Włostowski Tadeusz Łaszkiewicz-Tiszczenko Barbara 《Biological trace element research》2019,187(1):137-141
Biological Trace Element Research - Recent studies have demonstrated that reproduction reduces oxidative damage in various tissues of small mammal females. The present work was designed to... 相似文献