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991.
Eine nèue foliikole Flechte (Pleurotrema epiphylla sp. n.) aus Zaïre (Zentral-Afrika) wird beschrieben. Die systematischen Beziehungen der neuen Art zu den anderenPleurotrema-Arten und die Stellung der GattungPleurotrema innerhalb der FamilieParatheliaceae wird kurz diskutiert.  相似文献   
992.
993.
994.
Peanut agglutinin (PNA), a lectin specific for terminal d-galactosyl residues, was found to react with embryonal carcinoma cells, but not with their differentiated derivatives. Receptors for PNA were detectable at the surface of all cells of the quasinullipotent F9 line and on only 50% of the multipotent PCC3/A/1 line. The fraction of the PCC3/A/1 population which expresses the F9 antigen was found to be included in the subpopulation carrying the PNA receptors. PNA+ and PNA? subpopulations of PCC3/A/1 were separated by a PNA-mediated reversible agglutination of PNA+ cells with rabbit erythrocytes. These subpopulations were essentially F9+ and F9?, respectively.  相似文献   
995.
Populations of Periplaneta americana (L.) were exposed for 8–20 week periods in specially designed rooms to 254 nm UV at low intensity (50–115 ergs sec–1cm–2), high intensity (160–220 ergs sec–1cm–2), or to white light. The rooms contained tables and chairs to simulate occupied space, with food and water placed in positions exposed to UV radiation. General irradiation (where the whole room was exposed to UV) at 115 ergs sec–1cm–2 and above was effective in producing high mortality in all stages except 8–10th instar nymphs and adults. Hot-spots irradiation (where UV lamps were placed behind table and chair harborages) produced high mortality only in 1 st-3rd instar nymphs which would result in slower elimination of a population. Crude aggregation pheromone was not successful in holding cockroaches close to radiation sources or substantially increasing mortality under the conditions of the experiments.
Zusammenfassung Populationen von Periplaneta americana (L.), die hinsichtlich ihrer Alterszusammensetzung (2.–3.; 5–6.; 8.–10. und adultes Stadium) und der Anzahlen in jedem Stadium festgelegt waren, wurden für 8–20 Wochenperioden in speziell dafür entworfenen Räumen einer 254 nm UV-Bestrahlung mit geringer (50–115 erg sec–1cm–2) oder hoher (160–220 erg sec–1cm–2) Intensität oder weißem Licht (als Kontrolle) ausgesetzt. Die Räume enthielten Tische und Stühle, um bewohnten Raum mit natürlichen Zufluchtsstätten mit Nahrung und Wasser an Stellen, die der UV-Bestrahlung unterlagen, zu simulieren. Ganzraumbestrahlung mit 115 erg sec–1cm–2 und darüber erzeugte hohe Mortalität bei 1.–3. und 5.–6.-Larvenstadien, örtliche Bestrahlung (UV-Lampen hinter Tisch- und Stuhl-Zufluchtsstätten) dagegen nur beim 1.–3.-Stadium, was zu einer langsameren Ausrottung einer Population führen würde. Ungereinigtes Aggregationspheromon als Zusatz, um Schaben dicht an die UV-Quellen zu locken und sie hier zu halten, war offenbar unwirksam, da eben die Mortalität nicht signifikant zunahm. Dieses Versagen war in erster Linie auf die Konkurrenz mit der Fülle von natürlichem Pheromon, das von den gewohnten Zufluchtsstätten ausging, zurückzuführen, verbunden mit der dem UV-Licht innewohnenden Abschreckung. Dennoch darf man annehmen, daß UV-Bestrahlung einen bedeutsamen Wert für die Verhinderung eines Populationswachstums (durch Ausschalten junger Larvenstadien) besitzt, besonders dort, wo chemische Bekämpfung aus Gesundheits- und Sicherheitsgründen oder wegen gesetzlichen Einschränkungen nur begrenzt möglich ist.
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996.
The effect of ten derivatives of carbonylcyanide phenylhydrazone on growth of bacteria, yeast and different species of filamentous fungi was investigated. In yeast and mitochondria isolated from rat liver the effect of these derivatives on the respiratory activity was also followed. The relative efficiency of the individual derivatives of earbonylcyanide phenylhydrazone was determined on the basis of the results obtained. It was shown that derivatives, in which the substituent on the benzene ring causes simultaneously an increase of acidity and lipophilicity of the derivative as compared with the non-substituted carbonylcyanide phenylhydrazone (4-trifluoromethoxy-, 3-chloro-, 4-chloro and 3,4-dichloroderivatives) were most effective.  相似文献   
997.
Proteins of a crude enzyme preparation obtained from the cultivation medium of the basidiomycetePhellinus abietis were separated by gel filtration and ion-exchange chromatography. The preparation contained a minimum of three enzymes capable of splitting α-d-mannosidic bonds: α-mannosidase, exomannanase, and endomannanase, which were separated. Some properties of the mannanase complex of the crude enzyme preparation, and of a partially purified α-mannosidase were examined. The mannanase complex exhibited two pH optima, its temperature optimum being at 46 °C The pH optimum of purified α-mannosidase was at pH 5.0, the temperature optimum was at 60 °C; the enzyme had a relatively high heat stability. The Km of α-mannosidase forp-nitrophenyl α-d-mannopyranoside was 1.5 x 10−5 M. Pure α-mannosidase did not split mannan.  相似文献   
998.
999.
Crystal-containing organelles in cells of virus infected plants lying at chloroplasts and mitochondria are identical with single membrane-bound microbodies containing crystals of catalase described in healthy plants. Massive complex inclusions caused by turnip mosaic virus very frequently contain the same microbodies with crystal inclusions; that phenomenon may be related to some pathophysiological changes of virus infected plants. Comparable proteinaceous crystals, but not lying within microbodies limited by a membrane, may also be found in cytoplasm of infected cells. These crystals are sometimes surrounded by a substance resembling the microbody matrix. Disintegrated cytoplasm of virus infected cells may also contain the same crystals lying free in “empty spaces”. Cytopathological effects responsible for this phenomenon and possible artifacts as well are discussed.  相似文献   
1000.
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