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31.
The existence of six amylase heterogeneity variants in serum and urine has been discovered in a group of 111 families with twins, and the frequence of each variant was determined. It had been shown that each of these amylase heterogeneity variants is inherited codominantly, and the mode of inheritance is demonstrated schematically.These amylase heterogeneity variants may be used as an aid to twin zygosity determination and also in paternity problems.  相似文献   
32.
From the results obtained in the present work it is concluded that gamma globulin of the 7 S type (γG) which represents the main immunoglobulin component of pig colostrum, differs from serum γG globulin by the presence of another type of polypeptide chain, designed L2; the latter was detected after S-sulfonation in starch gel electrophoresis as the fastest moving component and its immunoelectrophoretic pattern shows the presence of two precipitating components. Preparation of soluble heavy and light chains enabled us to study them imunochemically. The heavy chain is represented by two zones; the fainter one was not detected in comparative analysis of the heavy chain of serum γG globulin. The L1 chain of colostral gamma globulin and the light chain of serum gamma globulin seem to contain three precipitating components, one of which appears due to aging of the chain solution in the presence of glycine. The material from colostrum seems to contain a larger amount of this component than serum. Further it was shown that the component arising in this way is antigenically closely related to the heavy chain.  相似文献   
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Colour tests for study of the nuclear apparatus ofChlorella cells are described. It can be concluded from the results thatChlorella cell nucleus contains a relatively large nucleolus; the peripheral layers of the nucleus are rich in chromatin only in the nuclear division phase. The nucleus divides by a simplified form of mitosis, characterized morphologically by simple constriction.  相似文献   
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V p?edlo?ené práci je sledován ú?inek humusových látek aplikovaných na listy cukrovky post?ikem. Sou?asně je ově?ována vhodnost kombinace humusových látek s minerálními ?ivinami. Ukazuje se, ?e post?ik humusovými látkami zvlá?tě v kombinaci s minerálními ?ivinami p?íznivě ovlivňuje r?st cukrovky, zvy?uje váhu list? i ko?ene a celkové mno?ství cukru v ko?eni. Ú?inok post?iku humusovými látkami je vět?í u rostlin pěstovaných ve vodní kultu?e a st?íkaných ?ivným roztokem s kompletněj?ím zastoupením minerálních prvk?. Humusové látky p?i aplikaci na list vyvolávají podobné změny v anatomické stavbě pletiv a orgán?, jako p?i jejich aplikaci do ?ivného roztoku ke ko?en?m. Humusové látky zvlá?tě v kombinaci s minerálním roztokem zvy?ují v listech cukrovky mno?ství chlorofylu a zvy?ují intezitu fotosyntézy. Post?ik humusovými látkami zvy?uje sou?asně transpiraci cukrovky.  相似文献   
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The mutagenic activity of more than 120 antimicrobial agents and protective components was investigated. Only Kathon showed a consistent increase in revertant counts in the Ames test onSalmonella typhimurium. The hereditary bleaching test onEuglena gracilis used for detecting extranuclear mutations, showed positive results for Kathon, triethanolamine and diamine silver tetraborate.  相似文献   
39.
Butomus umbellatus L. is a plant species typical of littoral communities of river and stream shores. It can form continuous stands in shallow reservoirs with fluctuating water level. Their expansion is promoted by: (a) intensive vegetative reproduction of plants, (b) crowded sprouting from rhizome fragments on emerged pond bottom, (c) shallow water layer in the year following summer drainage. Expansion of B. umbellatus depends on ploidy level: two cytotypes were found in the Czech and Slovak Republics, differing in their reproductive ability. Seed production of triploids is strongly limited (they are self-incompatible within clones), while diploids can be fully fertile. Nevertheless, even in diploids, the efficiency of seed reproduction under natural conditions is low. Triploids spread by intensive vegetative reproduction, which is decisive for clonal growth of populations and their regeneration after scraping of bottom surface. During seasonal development, maximum of aboveground biomass is produced in early summer, while underground biomass increases till autumn. Growth of the plants is limited by cutting before maximum underground biomass is attained, or by duck grazing.  相似文献   
40.
The dynamics of individual endogenous cytokinins within the growth cycle (subculture interval) of an auxin-dependent and cytokinin-independent cell suspension culture ofNicotiana tabacum L. (strain VBI-0) were determined using high performance liquid chromatography and radioimmunoassay. In cells grown at an optimum auxin concentration the transient maxima of N6-(2-isopentenyl)adenine and N6-(2-isopentenyl)-adenosine correlated with the onset of cell division. Cultivation of the cells in a partially auxin-deprived medium resulted in ca. tenfold increase of all endogenous cytokinins. A very distinct maximum of N6-(2-sopentenyl) adenine appeared at the beginning of subculture. This indicates that a lack of auxin induced an accumulation of cytokinins predominantly in the form of the free bases, which are physiologically more active than the corresponding ribosides.Abbreviations iP N6-(2-isopentenyl)adenine - [9R]iP N6-(2-isopentenyl)adenosine - t-Z trans-zeatin - t-[9R]Z trans-zeatin riboside - IAA indole-3-acetic acid - NAA 1-naphthaleneacetic acid - 2,4-D 2,4-dichlorophenoxyacetic acid - f.w. fresh weight - SBI subculture interval - C complete medium - PAD partially auxin-deprived medium - RP-HPLC reverse phase high performance liquid chromatography - RIA radioimmunoassay - PAL L-phenylalanine ammonia lyase  相似文献   
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