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61.
The frutescent species of the lichen genusCaloplaca are usually united in sect.Thamnoma, but they do not form a natural group. They are derived from different species groups within sect.Gasparrinia from different parts of the world, presumable from species having scleroplectenchymes in cortex and medulla. The algal cells are concentrated between the scleroplectenchymatic strands in large and dense groups, from where medullary plectenchyme extends to the cortex and forms characteristic pseudocyphellae there.—Most of the species seem to be ornithocoprophilous; they grow on rocks along marine coasts where much fog is induced by cold currents.—Caloplaca cribrosa is endemic in Tasmania and New Zealand,C. regalis and the doubtfulC. ambitiosa belong to the antarctic element.C. fragillima from central Chile seems to be propagated by thallus fragments.C. coralloides andC. thamnodes are endemic to California and Baja California respectively.C. cladodes from the Rocky Mountains deviates in many characteristics from the other species i.a. by it different ontogenetic development, reduced spore septum, and cementing amyloid polysaccharides within the scleroplectenchymatic strands. The African species are characterized by their distinctly dorsiventral lobes and usually possess oil cells in some of the paraphyses.Caloplaca bonae-spei, C. fragillima andC. thamnodes are new to science. 相似文献
62.
Josef Makovitzky 《Histochemistry and cell biology》1978,55(4):319-324
Zusammenfassung Die Untersuchungen erwiesen, daß die Farbstoffe 1:9-Dimethyl-Methylenblau, Azur A und N,N-Diäthylpseudoisozyaninchlorid für topo-optische Reaktionen an der Membran von Erythrocyten geeignet sind. Die Farbstoffmoleküle werden an der Membran orientiert gebunden. Ihre Bindung kann durch Behandlung mit Präzipitationslösungen stabilisiert werden, und zugleich wird die Anisotropie verstärkt. Die optische Analyse ergab, daß 1:9-Dimethyl-Methylenblau und Azur A radiär zur Membran ausgerichtet sind, während sich N,N-Diäthylpseudoisozyaninchlorid membranparallel anlagert.
Tope-optical staining with thiazin and quinolin dyestuffs of the erythrocyte membrane
Summary The present studies prove the dyestuffs 1.9-dimethyl methyleneblue, azure A and N,N-diethylpseudoisocyanine chloride suitable for topo-optical reactions with the membrane of the red blood cell. The dye molecules are bound in orientated fashion. Treatment with precipitants stabilizes the binding of dye molecules and, in addition, it enhances the birefringence. Optical analysis revealed 1.9-dimethyl methyleneblue and azure A bound in radial position, however, N,N-diethylpseudoisocyanine chloride was bound parallel to the membrane's plane.相似文献
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Arthopyrenia endobrya from Southern Brazil is illustrated and described as a new species of lichens. The thallus is composed of filamentous green algae loosely surrounded by fungal hyphae. Both symbionts grow endophytically within the leaf cells of two species ofLejeuneaceae (Hepaticae). The algae and hyphae penetrate the cell walls of the host by means of fine perforations. The ascocarps develop between the leaves and perforate them with their apical region. The classification as a member of the genusArthopyrenia is preliminary. 相似文献
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Summary The kinetics of cell division and sister chromatid exchanges were studied in PHA-stimulated short-term cultivations of peripheral blood by means of the BUDR/FPG technique in controls and in five patients with 45,X/46,X,i(Xq) mosaicism. No significant differences in the length of the cell cycle were observed between 45,X/46,X,i(Xq) and control 46,XX cells. The number of SCE on late i(Xq) was only nonsignificantly elevated (0.6 per i(Xq)) against the value expected on the basis of its relative length. 相似文献
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The effects of glucose, glucose metabolites, protein-enriched rete testis fluid (RTF), selected androgens and phospholipids on the survival of testicular spermatozoa have been studied. The oxidative and glycolytic activity, motility and percentage of live cells were the criteria for assessing the viability of the spermatozoa washed free of the substances that had been added during storage. The addition of lithium lactate, sodium lactate and sodium pyruvate but not glucose was beneficial to the survival of testicular spermatozoa. Following 10 to 12 days storage at 4°C with added lactate or pyruvate testicular spermatozoa had a higher glycolytic activity than did control spermatozoa. The respiratory activity of stored testicular spermatozoa was maintained or depressed, depending on the density of spermatozoal suspension during storage. After 10 to 11 days storage in concentrated RTF or after exposure to selected androgens testicular spermatozoa utilized more glucose than after storage with lactate alone. However, this apparent response to androgens and RTF-proteins was the consequence of a higher survival rate of the spermatozoa rather than an increase in the metabolic activity of individual spermatozoa. These results indicate that metabolites of glucose may serve as substrates for spermatozoa in the epididymis while certain androgens and macromolecules occurring in reproductive tract fluids may play important roles in the survival of spermatozoa during their period of maturation in the epididymis. 相似文献