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1.
The activities of the kallikreins and the kininases and the peptides bound with them in the venoms of Central Asian snakes have been studied. It has been found that when the whole venoms are used an interference of the enzymes with one another and also with potentiating or inhibiting peptides takes place. Bradykinin-potentiating activity the nature of which is connected with an inhibiting action on kininase II has been found in the low-molecular-mass fractions of cobra and viper venoms. The inhibiting activities of the venoms have been characterized in relation to the angiotension-converting enzyme from bovine kidneys and also purified dipeptidyl carboxypeptidase from karakurt (black widow) venom.Institute of Biochemistry, Uzbekistan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 257–261, March–April, 1992.  相似文献   

2.
Collective characteristics of the venoms belonging to various taxons of Central Asian snakes, demonstrating levels of toxicity and efficiency of hemorrhagic action, together with proteolytic, esterase, and phospholipase activities, have been obtained. A comparative analysis of the collective characteristics (portraits) of the venoms and their changes on degradative treatment has shown that the hemorrhagic action of the venoms of viperine and crotalid snakes is connected with metalloproteins. In contrast to the venoms of the elapids (cobras) the toxicity of the venoms of the viperine and crotalid snakes exhibits a dependence on the hemmorhagic effect and the activity of the metalloproteins causing it.Institute of Biochemistry, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 560–564, July–August, 1991.  相似文献   

3.
The objective of the research was to characterize the 241Am distribution in six operationally defined chemical and mineralogical phases of soil samples taken from the Rocky Flats Environmental Technology Site (RFETS). Soil samples were subjected to selective sequential fractionation procedures to determine 241Am association with the soluble, exchangeable, carbonate, organic, sesquioxide and silicate fractions. The highest percentage of 241Am was found to be associated with the sesquioxide (hydrous oxide) fraction (39–47%), with lesser amounts in the soluble (14–17%), exchangeable (4–9%), carbonates (4–17%), organic (3–13%), and silicate (10–21%) soil fractions. Differences between americium and plutonium association with various soil fractions were observed.  相似文献   

4.
A study was undertaken to evaluate the distribution of Al, As, Cr, Cu, Fe, Mn, Ni, Pb, Ti, V and Zn in fly ashes collected in the electrostatic precipitator of a thermal power plant in San Nicolás (Argentina). Five samples were collected during one week of operation. For the fractionation, the scheme applied consisted in extracting the elements in four fractions namely (i) soluble and exchangeable elements; (ii) carbonates, oxides and reducible elements; (iii) bound to sulfidic metals; and (iv) residual elements. Metals and metalloids at μg g− 1 level were determined in each fraction by inductively coupled plasma optical emission spectrometry (ICP OES). For validation, a standard reference material (SRM 1633 coal fly ash) from NIST was subjected to the same chemical sequential extraction procedure that the samples. X-ray diffraction powder (XRD) analysis and scanning electron microscopy (SEM) were used to characterize the major minerals present in the matrix. Total analyte concentration (in μg g− 1) varied from 10.6 for Pb to 17,622 for Al. Minimum and maximum concentrations (in μg g− 1) found in individual samples in the four fractions were: Al, 92.7–9668; As, < 0.3–143; Cr, 2.0–10.4; Cu, < 0.2–35.6; Fe, < 0.3–4992; Mn, < 0.1–128; Ni, < 0.3–139; Pb, < 0.5–9.1; Ti, < 0.3–2243; V, 17.0–112.9; and Zn, < 0.1–68.2. The leachability of the 11 elements under study proved to be different. Low percentages of Al (1%), V (7%) and Cr (8%) were detected in the most bioavailable fraction. Arsenic was found to be most abundant in the non-silicate phase, represented by the second and third fractions, while Cr, Fe, Ni, Pb and Zn were mostly associated to the residual fraction.  相似文献   

5.
The lipid composition of the roots ofBryonia alba (Cucurbitaceae) have been studied: It consists of fractions of 3-acyloxy-24-alkyl(alkenyl)-cholest-7-enes (I), triacylglycerols (II), 1,2-diacyl-3-monoglycopyranosyl-sn-glycerols (III), 1,2-diacyl-3-diglycopyranosyl-sn-glycerols (IV), 1,3-bis(3-sn-phosphatidyl)glycerols (V), 3-sn-phosphatidylethanolamines (VI), 3-sn-phosphatidylcholines (VII), and methyl esters of fatty acids (VIII). The amount of unsaturated fatty acids in the lipid fractions (I–VIII) is 60–94%, the main component being linolenic acid.A. L. Mndzhoyan Institute of Fine Organic Chemistry of the Academy of Sciences of the Armenian SSR, Erevan. Translated from Khimiya Pridodnykh Soedinenii, Vol. 6, pp. 781–785, November–December, 1980.  相似文献   

6.
Five fractions have been obtained by the fractional precipitation of the water-soluble polysaccharide with alcohol: water-insoluble (fractions 1 and 2) and water-soluble (fractions 3-5). Their Fourier IR spectra have been studied and, on the basis of the results obtained, it is suggested that the water solubility of the fractions examined is connected with strong hydrogen bonds.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 89 14 75. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 202–205, March–April, 1995. Original article submitted November 14, 1994.  相似文献   

7.
The protein composition and the kinetics of the quantitative changes in the various protein fractions during the ontogenesis of protoplast and hybrid cultures ofTrichoderma harzianum have been studied. In the exponential growth phases of both cultures the highest amount of protein was contained in the water-soluble (33.0–33.2%) and salt-soluble (31.0–32.0%) fractions. The protein contents of the water-soluble fractions of the cultures studied were similar to those in meat and clover and were 3.5 times greater than in yeast.Institute of Microbiology, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 41 71 29. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 209–211, March–April, 1998.  相似文献   

8.
Relative humidities have been measured for mixed aqueous electrolyte system of ammonium and potassium chlorides by the hygrometric method at total molalities from 0.3 to 6 mol-kg–1for ionic-strength fractions yof NH4Cl of 1/3, 1/2, and 2/3 at 25°C. The data allow the calculation of new water activities and osmotic coefficients. The proposed ECA (extended composed additivity) rule of calculation of water activity in mixed aqueous electrolyte solutions from the water activities of a single component is extended to this system. The experimental results and the predictions of the ECA rule are compared with the Robinson–Stokes, Reilly–Wood–Robinson, the Pitzer, and the Lietzke–Stoughton II models. Predictions made using these models are, in general, consistent with our results. From these measurements, the Pitzer mixing ionic parameters are determined and used to predict the solute activity coefficients in the mixture for different ionic-strength fractions.  相似文献   

9.
Hemicellulose fractions possessing biological activity have been isolated from the lignocellulose of nonwoody plants (kenaf tow, cotton stems) by alkaline extraction.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 89 14 75. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 364–367, May–June, 1998.  相似文献   

10.
The kinetics of electrolyte extraction into water and the electrosurface properties (adsorption of potential-determining ions H+ and OH and ζ potential) of five fractions of schungite III (particle sizes of < 5, 50–100, 160–400, 400–1000, and 1600–2500 µm) are studied in aqueous NaCl, CaCl2, and AlCl3 solutions at different pH values. It is shown that, in water and NaCl and CaCl2 solutions, the point of zero charge (PZC) of the particles with sizes of 50–100 and 160–400 µm is observed at pH 4.0 and is independent of the electrolyte concentration. The isoelectric point (IEP) for small (<5 µm) schungite III particles is observed at pH 2.8. The IEP position is independent of CaCl2 concentration, but it shifts to pH 2.4 when NaCl concentration increases to 0.1 M. The disclosed differences in the PZC and IEP values may be caused by different compositions of particles of different fractions. In a 10−5 M AlCl3 solution, schungite particles demonstrate three IEPs (pH 3.0, 4.5, and 7.4) due to different degrees of AlCl3 hydrolysis at different pH values.__________Translated from Kolloidnyi Zhurnal, Vol. 67, No. 4, 2005, pp. 450–457.Original Russian Text Copyright © 2005 by Aleinikov, Lorentsson, Chernoberezhskii.  相似文献   

11.
The mixed aqueous electrolyte system of ammonium and lithium chlorides has been studied by the hygrometric method at 25°C. The relative humidities of this system are measured at total molalities from 0.3 to 6 mol-kg– 1 for different ionic-strength fractions y of NH4Cl with y = 0.33, 0.50, and 0.67. The data obtained allow the deduction of new water activities and osmotic coefficients. The experimental results are compared with the predictions of the ECA (extended composed additivity) law proposed in our previous work. The Zdanovskii–Stokes–Robinson (ZSR), the Robinson–Stokes (RS), Reilly–Wood–Robinson (RWR), the Pitzer, and the Lietzke–Stoughton (LS II) models are also compared with our results. Predictions made using these models are, in general, consistent with our results. From these measurements, new Pitzer mixing ionic parameters are determined and used to predict the solute activity coefficients in the mixture for different ionic-strength fractions.  相似文献   

12.
It has been established by electrophoresis in polyacrylamide gel that the protein component of the lipopolysaccharide-protein complex ofYersinia pseudotuberculosis consists of two poly-peptides with molecular weights of 42,000–45,000 and 18,000–20,000. These polypeptides have been detected in the cell wall ofY. pseudotuberculosis as the main components. Protein fractions B-2 and B-3, differing with respect to solubility in phenol, were isolated from the LPPC ofY. pseudotuberculosis by extraction with hot 45% phenol. These protein fractions had the same polypeptide composition, which is characteristic for membrane proteins. B-3 included the LPS component and B-2 contained lipid A or fragments of it as impurity. Fractions B-3 and B-2 precipitated with antiserum to the LPPC.Pacific Ocean Institute of Bioorganic Chemistry of the Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 92–97, January–February, 1980.  相似文献   

13.
Nanodisperse TiO2 hydrosol and two of its fractions stabilized by HCl are studied. The anatase nanocrystalline fractions are obtained by the stepped coagulation of the stable sol using dependence of coagulation thresholds on size of nanocrystallites. X-Ray investigation in small and wide angles of scattering has revealed that the anatase nanocrystallites have a shape of 2.5–3 nm thick elongated plates with 8–18 nm lateral sizes. The concentrated hydrosols with the reduced HCl content prepared from the anatase fractions are shown to form an ordered structure. Narrow fractions of TiO2 nanocrystallites obtained from the stable hydrosols seem to be promising for the preparation of highly ordered structures with a nanometer periodicity.  相似文献   

14.
Products of the oxidation, polymerization, and esterification of tocopherols and esters of phytol with aliphatic acids have been identified in fractions of an alcoholic extract of shed plane leaves by means of mass-spectrometric analysis.Deceased.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, FAX (3712) 62 73 48. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 363–371, May–June, 1994.  相似文献   

15.
A new geometrical particle size separation method in the range of submicrometer has been developed for coal fly ash. Coal fly ash particles prefractionated less than 5m in geometrical diameter were fractionated with a coupling of supersonical dispersion in methyl alcohol and filtration through antistatic Nucleopore filter into >1.0, 1.0–0.8, 0.8–0.6m.Submicrometer (1.0–0.6m) and micrometer coal fly ash (25–20m) were separated into six density fractions and their compositions measured by SEM-EDX were compared. For the both size fractions, for the low density fractions (<2.8 g/cm3) consisted mainly of aluminosilicates and the fractions of 2.8–3.2 g/cm3 consisted of oxides of aluminum, silicon and calcium, and in the fraction above 3.2 g/cm3 iron was rich. In submicrometer fly ash, phosphor and sulfur concentrated to the particles rich in calcium. In the heaviest fraction, the particles containing over 30 wt% titanium as oxide observed among the particles rich in iron. These fractions were revealed not as a single component, but as mixtures of several components.  相似文献   

16.
Summary 1. The identity of the IR spectra of the main types of amber (transparent, semitransparent, opaque and bone ambers) in the 700–2000 cm–1 region has been confirmed. At the same time, differences between them have been shown by elemental analysis.2. In order to isolate the fraction of amber soluble in alcohol, extraction with boiling alcohol instead of by prolonged extraction at room temperature has been proposed.3. The amber fraction soluble in alcohol and petroleum ether can be separated into acid and ester (lactone) fractions by successive treatment of its ethereal solution with 1% and 15% aqueous alkalis.4. The acid fraction isolated from the alcohol-soluble and the petroleum ether-insoluble fractions of amber have similar IR spectra but differ in elemental composition.5. Succinin contains lactone (or ester) groupings whose hydrolysis forms hydroxyacids.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 6, pp. 429–436, 1966  相似文献   

17.
Summary 1. Individual fractions of phosphatidylcholines, phosphatidylethanolamines, phosphatidylinositols, and the X2 and X3 phospholipids have been obtained from the combined phospholipids, freed from carbohydrates, of the seed kernels of the cotton plant of variety Tashkent-3.2. The compositions and position distributions of the fatty acids in the main fractions of phospholipids have been studied.3. The possible molecular composition of the phosphatidylcholines, phosphatidylethanolamines, and phosphatidylinositols have been calculated.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 155–158, March–April, 1976.  相似文献   

18.
A new method has been developed for obtaining individual protamines which is based on the chromatographic separation of an ultrasonically treated nucleoprotamine solution. The separation of the nucleoprotamine from the gonads of the Caspian sturgeonAcipenser stellatus on CM-Sephadex G-25 led to the isolation of three fractions. Analysis showed that two fractions contained homogeneous protamine — stellins A and B. The third fraction contained nonprotamines and DNA.Moscow Technological Institute of the Meat and Dairy Industry. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 378–381, May–June, 1985.  相似文献   

19.
The structure of fractions isolated by thermal sublimation of ultradisperse polytetrafluoroethylene (UPTFE) powder has been studied by IR spectroscopy. At 50°C–160°C, fractions of highly amorphous fragments are condensed on a cold receiver; the fragments are constructed from branched chains with terminal olefin groups. Fractions isolated at 300°C and higher are close in structure to PTFE and are highly crystalline. It is assumed that sample amorphism is due to the irregular distribution of the fractions of fragments with terminal olefin and lateral fluoromethyl groups in the structures.Original Russian Text Copyright © 2004 by L. N. Ignatieva, A. K. Tsvetnikov, O. N. Gorbenko, T. A. Kaidalova, and V. M. Buznik__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 5, pp. 830–836, September–October, 2004.  相似文献   

20.
Summary 1. The dioxane lignin of ripe cotton-plant stems has been separated into six fractions of different molecular weights which were fairly homogeneous and differed considerably in their molecular weights.2. It follows from the semiempirical formulas that in all the fractions guaiacyl structural units predominated. The chemical nonidentity of the fractions is shown by the different amounts of functional groups in the phenylpropane structural units and by the relative optical densities of the main bands in the IR spectra of the fractions.3. The low-molecular-weight fraction differed markedly from the others by a higher content of carbohydrates bound to the lignin and by a greater degree of oxidation.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 69–74, January–February, 1979.  相似文献   

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