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51.
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A single X-chromosome balancer-bearingCelegans ♂+, as a founder of a strain (AF1), was isolated directly from Fl progeny of irradiated+dpy-8unc-3/lon-2++ hermaphrodites on the basis of the absence of recombinant F2 categories. The balancer chromosome (Bal-X-1) suppresses recombination over a two-thirds section of the X chromosome (between genesdpy-8 andlet-2) and is associated with a reciprocal translocation between linkage groups (LG) X and I. Animals homozygous for the translocation (szT1(X:1)) are nonviable. Hermaphrodites heterozygous for the translocation segregate male selfprogeny at a frequency of 0.08-0.12.Bal-X-l carries the marker mutationlon-2(e678) and can be detected cytologically. This balancer chromosome proved useful for rnaimaininga number of X-linked lethal mutations and deficiencies inC. elegans. 相似文献
53.
A numerical algorithm has been developed for the estimation of the mechanical parameters of the human respiratory system. In order to estimate the pulmonary resistance and the dynamic pulmonary elastance, the transpulmonary pressure and the airflow at the mouth or nose are expanded in Chebyshev series. The nonlinear mathematical lung model and a set of measurements for airflow and pressure are then handled by the numerical technique. The lung model includes a component to account for turbulent flow in the larynx and trachea. This contribution presents an alternative method for lung parameter estimation and differs from most existing methods in that it does not need measurements for the tidal volume. It therefore eliminates the use of a body plethysmograph. The method may also find potential application to various other parameter identification problems. 相似文献
54.
M. J. Babiano J. J. Aldasoro J. Hernández-Nistal D. Rodriguez A. Matilla G. Nicolás 《Physiologia plantarum》1984,61(3):391-395
Nonanoic acid, which inhibits germination in several seeds, enhanced ion efflux from embryonic axes of Cicer arietinum L., especially at temperatures above 25°C. Other short chain fatty acids had little effect on germination and ion leakage. Nonanoic acid also decreased uptake of 86 Rb+ and 22 Na+ and increased efflux of both isotopes from the embryonic axes into the incubation solution. Fusicoccin, which stimulates early germination in C. arietinum , counteracted the effects of nonanoic acid at both 25 and 30°C. These results suggest that nonanoic acid affects the integrity of plasmalemma and other membrane systems. Nonanoic acid thus inhibits cell elongation during early germination by disturbing ion exchange and inhibiting water uptake. 相似文献
55.
Selection of Wine Yeasts for Growth and Fermentation in the Presence of Ethanol and Sucrose 总被引:5,自引:3,他引:2 下载免费PDF全文
Tahía Benítez Lucas del Castillo Andrs Aguilera Jaime Conde E. Cerdolmedo 《Applied microbiology》1983,45(5):1429-1436
To optimize the conversion of carbohydrates to ethanol, strains of several Saccharomyces species were examined for the ability to grow and ferment in a range of sucrose and ethanol concentrations. A total of 632 wine yeasts, most of them isolated from wineries in Andalusia and Extremadura, southwestern Spain, were subjected to screening and selection. Growth and fermentative capacity in different ethanol and sucrose concentrations varied from one strain to another. There was no correlation between growth and fermentative capacity. The best 35 strains grew in 15% ethanol and fermented in 18% ethanol. Ethanol accumulated, although at a reduced rate, after the cells stopped growing. Most yeast strains were highly fermentative in 50% sucrose. Some of them effectively utilized the carbohydrates of the culture, yielding final ethanol concentrations of > 14%. Of the 35 selected strains, 16 were promising for genetic analysis and breeding because of their capacity to sporulate. These strains were homothallic, and their spores were viable. The meiotic products analyzed so far were also homothallic. 相似文献
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R. Håkanson F. Sundler A. Nobin N. -O. Sjöberg L. Edvinsson L. -I. Larsson 《Cell and tissue research》1974,150(2):281-290
Summary In the mammalian pituitary formaldehyde-ozone treatment induces strong fluorescence in the cells of the pars intermedia and moderate to strong fluorescence in numerous cells of the pars distalis. Maximum excitation is at 370–375 nm and maximum emission at 495–505 nm. The properties of the cellular fluorescence are indistinguishable from those of tryptamine or peptides with NH2-terminal tryptophan. From chemical analysis such peptides seem to occur abundantly in the mammalian pituitary. The concentration of these peptides agrees very well with the number and fluorescence intensity of the cells in all species studied. Furthermore, the tryptophyl peptides in the various parts of the pig pituitary have a distribution quite parallel to that of the fluorescent cells. As we have failed to detect tryptamine in the pituitary, we conclude that the formaldehyde-ozone-induced fluorescence in the adenohypophysis reflects the presence of tryptophyl peptides.This study was supported by grants from the Swedish Medical Research Council (04X-1007; 04X-3764), the Ford Foundation, Harald and Greta Jeanssons stiftelse and Riksföreningen mot Cancer (660-K73-01X).For brevity occasionally referred to as tryptophyl peptides. 相似文献
58.
O. de Bolòs 《Plant Ecology》1970,21(1-3):49-73
Résumé Le climat chaud et humide de la Ligurie méditerranéenne détermine la réapparition de quelques groupements végétaux connus de la Catalogne et rares ou nuls en Languedoc: Inulo-Oryzopsietum miliaceae, Cichorio-Sporoboletum poiretii, Hyparrhenietum hirto-pubescentis, Rubo-Coriarietum.Le caractère particulier de la végétation ligure a été exprimé par des groupements spéciaux: Pistacio-Rhamnetum alaterni, qui remplace le Quercetum cocciferae, groupements à Ostrya carpinifolia et à Brachypodium pinnatum des endroits frais, groupements buissonnants à Erica arborea et Genista germanica, à Rosmarinus et Genista cinerea, Asplenio-Campanuletum macrorhizae des rochers, etc.
Summary The warm and humid climate of the Mediterranean Liguria determines the reappearance of some communities, known in Catalonia, and seldom or not existing in Languedoc: Inulo-Oryzopsietum miliaceae, Cichorio-Sporoboletum poiretii, Hyparrhenietum hirto-pubescentis, Rubo-Coriarietum.The particular character of the Liguric vegetation is expressed in special communities: Pistacio-Rhamnetum alaterni, which replaces the Quercetum cocciferae, communities with Ostrya carpinifolia and with Brachypodium pinnatum in the fresh places, bushy communities with Erica arborea and Genista germanica, with Rosmarinus and Genista cinerea, Asplenio-Campanuletum macrorhizae of the rocks, and so on.
Zusammenfassung Das warme und feuchte Klima der mediterranen Ligurie bestimmt das Wiedererscheinen einiger Pflanzengesellschaften, die in Katalonien bekannt sind, aber selten oder nicht in Languedoc vorkommen: Inulo-Oryzopsietum miliaceae, Cichorio-Sporoboletum poiretii, Hyparrhenietum hirto-pubescentis, Rubo-Coriarietum.Der eigenartige Charakter der ligurischen Vegetation ist in besonderen Pflanzengesellschaften ausgedrückt: Pistacio-Rhamnetum alaterni, das das Quercetum cocciferae ersetzt, Gesellschaften mit Ostrya carpinifolia und mit Brachypodium pinnatum der frischen Standorte, Erica arborea-Genista germanica-Silikatbodengebüsche, Rosmarinus-Genista cinerea-Kalkbodengebüsche, Asplenio-Campanuletum macrorhizae der Felsen usw.相似文献
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