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11.
The influence of He-Ne laser radiation (632.8 nm, 56 J/m2, t = 10 s) and phytohaemagglutinin (PHA, 2 micrograms/ml) on chromatin structure in human lymphocytes was studied by electron microscopy using ultrathin cell sections. Morphometric analysis of extranuclear condensed chromatin masses was performed 1 h after the irradiation or after the beginning of PHA treatment. In the irradiated cells the following insignificant changes were revealed: decrease in the relative area of the nucleoplasmic chromatin, increase in the relative area of decondensation zones as well as increase in the number of clumps of nucleoplasmic chromatin and relative length at their boundary with nucleoplasma. The tendency of these morphological changes may be interpreted as functional activation of extranucleolar RNA synthesis in response to irradiation by red laser light. Action of PHA results in significant changes of the surfaces of chromatin clumps, namely increase in relative length of nucleoplasmic chromatin boundary and decrease in relative length of perimembranous chromatin boundary with nucleoplasma as well as some less expressed delamination of the chromatin masses from the nuclear membrane. These essential changes may reflect chromatin activation by proliferative stimulus. Peculiarities of the ultrastructural reorganisation in the condensed chromatin after irradiation and PHA-treatment probably reflect the differences in the processes of gene activation caused by the two agents. 相似文献
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Nucleotide sequence of the Methylobacterium extorquens AM1 moxF and moxJ genes involved in methanol oxidation 总被引:10,自引:0,他引:10
The nucleotide sequence has been determined for two genes involved in methanol oxidation in the facultative methylotroph, Methylobacterium extorquens AM1. The two genes are moxF, encoding the 66-kDa subunit of the methanol dehydrogenase and moxJ, located immediately downstream from moxF, which encodes a 30-kDa protein with unknown function. This information completes the sequence of the 5.86-kb XhoI-SalI fragment containing the moxFJGI region in M. extorquens AM1, and the structure of this gene cluster is presented. Evidence is presented that moxJ is also present in Paracoccus denitrificans. The aa sequence of MoxJ has provided little information concerning its function, but it does appear to contain a signal sequence suggesting a periplasmic location. 相似文献
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Summary An integrated system for the collection, treatment and utilisation of piggery wastewater has been developed in Singapore which uses the cultivation of microalgae in high rate ponds to achieve reduction of BOD5 and COD5 of the effluent as well as producing single cell protein. A wide range of algal flora occurs in the ponds;Oocystis, Micratinium, Scenedesmus, Ankistrodesmus, Chlorella andOscillatoria spp were identified. Total algal counts, recorded from 1979 to 1981, ranged up to 107 per ml of pond water. There were considerable variations in the algal population and in the predominating species. No discernible pattern was evident. Consequently pond operations were frequently disturbed by these fluctuations in population which in turn was attributed to the heterogeneous composition of the piggery waste, to variable weather conditions and to predation by larger organisms particularlyMoina. After passing through the ponds, the total suspended solids were removed by a novel dissolved air flotation method which gave a clear effluent showing an 87% reduction in BOD5 value.
Resumen En Singapur se ha desrrollado un sistema integrado para le recogida, tratamiento y utilización de aguas residuales de pocilgas. Este sistema usa el cultivo de microalgas en estanques, de caudal rápido afin de reducir las DBO5 y DCO5 del efluencte produciendo asimismo proteínas celulares. La flora de algas producida en estos estanques es amplia y variada, habiendose identificado:Oocystis, Micratinium, Scenesdemus, Ankistrodesmus, Chlorella y Oscillatoria. Los recuentos totales de algas tomados desde 1979 a 1981 llegaron a alcanzar 10;7 por ml de agua del estanque. Se observaron variaciones considerables tanto en la población total de algas como en las especies predominantes sin que se pudiese, determinar un patrón de variación característico. Estas fluctuaciones en la población, causantes de frecuentes alteraciones en el funcionamiento del estanque, se atribuyeron a la composición heterogenea de los resuduos, a las variaciones climáticas y la predación por otros organismos particularmenteMoina Después de su paso por los estanque los solidos suspendidos totales se eliminaron mediante un nuevo método de flotación con aire disuelto, obteniendose un efluente limpio con una reducción de la DBO5 del 87%.
Résumé Un système intégré pour la collecte, le traitement et l'utilisation d'eaux résiduaires de porcherie a été développé à Singapoure. Il utilise la culture de micro-algues tant pour la réduction accélérée en lagune de la DBO5 et de la DCO de l'effluent que pour la production de protéines uni-cellulaires. On trouve une large gamme de flore algale dans les lagunes; des espèces d'-Oocystis, deMicratinium, deScenedesmus, Ankistrodesmus, deChlorella etd'Oscillatoria out été identifiées. Les comptages totaux d'algues, enregistrées de 1979 à 1981, ont donné jusqu' à 107 cellules par ml d'eau de la lagune. On a observé des variations considérables de population algale tant quantitatives que qualitatives. On ne discernait pas de spectres évidents. En conséquence, les opérations lagunaires ont été fréquemment perturbées par ces fermentations en population, qui, à leur tour, ont été attribuées à la composition hétérogène de l'effluent de porcherie, aux conditions atmosphériques et climatiques variables et à la prédation par des organismes plus conséquents, plus particulièrement desMoina. Après passage par les lagunes, les solides totaux en suspension ont été enlevés par une méthode nouvelle de flottation à l'air dissous, qui a donné un effluent limpide, présentant une réduction de DBO5 de 87%.相似文献
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Neil S. Painter Anthony Z. Almeida Kenneth W. Colebourne 《BMJ (Clinical research ed.)》1972,2(5806):137
Seventy patients with diverticular disease of the colon were treated with a high-residue, low-sugar diet including unprocessed bran. Follow-up for an average of 22 months showed marked relief of symptoms in 62 patients. Bowel habit was restored towards normal and abdominal discomfort relieved. Only seven patients were unable to give up the use of laxatives. Eight patients did not tolerate the bran diet, and one of these needed surgical treatment. None of the 62 patients who took the diet needed surgery. 相似文献
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