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The level of urine selenium in healthy adult population, 230 persons, was examined. Persons were selected regarding sex, ages, and smoking habits. No differences versus these observations have been found. For a total, group values are 16.96 Se nmol/creatinine mmol, SD=5.44. It is possible from a single-void specimen to express daily excretion of selenium.  相似文献   
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A?koliv na zá kladě mnoha pokus? se p? edpokládalo, ?e tzv. bÍlkovinná v?etena v buňkách tzn. buně?né inkluse X-viru kaktus? (Ca XV), jsou slo?ena z ?etních prodlou?ených ?ásti Ca XV, p?esto to dosud nebylo proká zá no. Proto jsme se pokusili pomocÍ fluoreskujÍcÍch protilátek doká ?at, ?e bilkovinná v?etena jsou skute?ně agregáty virových ?ástic. V těto práci jsme pouzili tzv. nep?Ímé metody. Nejprve jsme p? sobili na buňky obsahujÍci tato v?etena homologiokým antisé rem proti Ca XV, zÍskanym imunizacÍ králÍk? a teprve potom jsme buňky vlo?ili do roztoku fluoreskujicÍch protilátek proti králicimu γglobulinu. BÍlkovinná v?etena svitila potom ve fluorescen?nÍm mikroskopu silně ?lutozeleně (bylopou?ito fluoresceinisothiocyaná tu). Tato fluorescence ná m uká zala, ?e nastala pozitivnÍ reakce a ?e bÍlkovianá v?etena jsou slo?ena z virových ?ástic. ?etné kontrolnÍ pokusy potvrdily ná? základnÍ pokus.  相似文献   
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Conclusion This outline of the instrumentality of the technology/technique of representation in postcommunist Serbia is but a brief attempt to address the modes of production of identity in postmodernism, its legitimation in/of dominant discourse, and their embedding in common sense language and practice. Postcommunist Serbia is obviously a special situation:23 a particular case of the social appropriation and construction of enjoyment and desire, intimately related to the desires and various enjoyments of the members of the community, precarious in its collective affirmation. Based on the idea of contingent collectivity, faction-fiction, in its meta-critique seems to signal the emergence of a new régime in the relation between historical reality and its representation in historical narratives.This new régime, obviously, cannot be exhaustively (or even extensively) discussed in a brief paper like this one. Nevertheless, some (three) points of departure for the general discussion of postmodern modes of representation are still possible. One such point of departure is the contingence of representation, another the apparent paradigmatic similarity between trash talk-shows and Echoes and Reactions. And finally, much of iek's discussion does not seem to be restricted to the totalitarian metanarrative, and can be a significant contribution to the debate on power relations.Nikola Stojin is a Serbian Writer and Graduate Student in Comparative Literature at Rutgers University, New Brunswick, New Jersey.  相似文献   
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The influence of external sodium concentration on potassium (depolarizing agent)-stimulated calcium uptake and Ca+-dependent acetylcholine release by rat cerebral cortex synaptosomes has been studied. It was found that increased sodium concentration decreases both the Ca2+ uptake and the acetylcholine release, whereas a low external sodium concentration is stimulatory.  相似文献   
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The effect of sucrose on fruiting, seed production, and seed germination of lesser centaury [Centaurium pulchellum (Sw.) Druce] was examined using explants of flowers and flower buds. Sucrose concentrations in the culture medium ranged from 0.003 to 0.3 M. It has been shown that the number of auxiliary buds, capsules dimension, number of viable seeds per capsule and seed dimensions increased with the increase of sucrose concentrations. The highest values were recorded at sucrose concentrations higher than 0.03 M, except for seeds size, which were larger at sucrose concentration ranging from 0.003 to 0.1 M. The germination of in vitro produced seeds was affected by previous culture history: a higher germination percentage was obtained in seeds that were raised from explants originally grown on medium with sucrose concentrations higher than 0.003 M.  相似文献   
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Horse chestnut (Aesculus hyppocastanum L., Hyppocastanacea) is a relict species with a slow and complex reproductive cycle considered to have horticultural and medical importance. The cycle maybe circumvented via in vitro androgenesis. Androgenesis of horse chestnut was induced in microspores and anther culture on MS media. Some of the horse chestnut androgenic embryos were albinos. Addition of abscisic acid in media (in concentrations of 0.01, 0.1, 0.5, 1, 2, 5, 10, and 20 mg l?1) with horse chestnut androgenic embryos has circumvented the reproduction cycle barriers. The best results were achieved on medium with the lowest abscisic acid concentration (0.01 mg l?1) in microspore culture. The microspore culture proved to be a better model system for embryo production and albino embryo reduction than anther culture. Flow cytometry analysis after maturation treatments induced by ABA showed that 88 % of green embryos originating from microspore culture were haploid. However, 50 % of green embryos from anther culture were haploid. The remaining analyzed androgenic embryos, from both types of cultures were diploid.  相似文献   
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Ohne ZusammenfassungDie vorliegenden Versuehe wurden während meines kurzen Aufenthalts im Pflanzenphysiologisehen Institut der Universität Wien ausgeführt. Herrn Prof. Dr. Karl Höfler und Herrn Dr. H. Kinzel danke ich sehönstens auch an dieser Stelle für die Untersfützung während der Arbeit.  相似文献   
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