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81.
Jacques Simard Dominique Bérubé Märten Sandberg Karl-Heinz Grzeschik Richard Gagné Vidar Hansson Tore Jahnsen 《Human genetics》1992,88(6):653-657
Summary A cDNA for the human catalytic subunit (C) of cAMP-dependent protein kinase (PKA) has been cloned from a testis cDNA library. In the present study, we have determined the chromosomal localization of this gene using a cDNA for C as a probe. Southern blot analysis of genomic DNA from human/mouse cell hybrids revealed that the presence or absence of a 20-kbXbaI fragment, which hybridized with the C probe, was concordant with the presence of human chromosome 1.In situ hybridization to metaphase chromosome confirmed the somatic cell hybrid data and regionally mapped the C gene of PKA to the p36 band on chromosome 1. 相似文献
82.
83.
Marie-Laure Yaspo Nathalie Crété Zoubida Chettouh Jean-Louis Blouin Zohra Rahmani Dominique Stehelin Pierre-Marie Sinet Nicole Créau-Goldberg Jean-Maurice Delabar 《Human genetics》1992,90(4):427-434
To generate new chromosome 21 markers in a region that is critical for the pathogenesis of Down syndrome (D21S55-MX1), we used pulsed field gel electrophoresis (PFGE) to isolate a 600-kb NruI DNA fragment from the WA17 hybrid cell line, which has retained chromosome 21 as the only human material. This fragment, which contains the oncogene ETS2, was used to construct a partial genomic library. Among the 14 unique sequences that were isolated, 3 were polymorphic markers and contained sequences that are conserved in mammals. Five of these markers mapped on the ETS2-containing NruI fragment and allowed us to define an 800-kb high-resolution PFGE map. 相似文献
84.
S. R. Gradstein R. Klein L. Kraut R. Mues J. Spörle H. Becker 《Plant Systematics and Evolution》1992,180(1-2):115-135
Recognition of two different species in the liverwort genusMonoclea
Hook. (monotypic orderMonocleales), viz.M. forsteri
Hook. in New Zealand andM. gottschei
Lindb. in the New World, is supported by characteristics of the sporophyte, antheridial receptacle and secondary metabolites.M. gottschei produces the greatest variety of flavonoids and the largest amount of bisbibenzyls ever encountered in a liverwort. In contrast,M. forsteri is poor in secondary metabolites. Two allopatric subspecies are recognized inM. gottschei, based on characteristics of the antheridial receptacle: subsp.gottschei in Chile (Valdivian region, Juan Fernandez Is.) and subsp.elongata
Gradst. & Mues, subsp. nova, in tropical America. The exclusive occurrence inMonoclea of glucuronide and galacturonide flavone glycosides and the fact that capsule dehiscence may take place before full elongation of the seta are new arguments in support of the placement ofMonocleales in theMarchantiidae.
Publication Nr. 43 of the Arbeitskreis Chemie und Biologie der Moose, Universität des Saarlandes, Saarbrücken. This paper is dedicated to DrElla O. Campbell, Massey University, Department of Botany and Zoology, New Zealand on the occasion of her 80th birthday. 相似文献
85.
86.
Several preparative resolutions of 5,5-disubstituted hydantoins have been achieved via fractional crystallization of diastereoisomeric salts. The process can be extended by making use of the difference between the variation of solubilities of the hydantoins and their salts with α-methylbenzylamine as a function of the alkalinity of the medium. Optimization for each resolution procedure involves a refinement of the excess amount of base needed. © 1992 Wiley-Liss, Inc. 相似文献
87.
Nicole Benhamou Pierre J. Lafontaine Dominique Mazau Marie-Thérèse Esquerré-Tugayé 《Planta》1991,184(4):457-467
An antiserum raised against deglycosylated hydroxyproline-rich glycoproteins (HPGPs) from melon (Cucumis melo L.) was used to study the relationship between Rhizobium infection and induction of HRGPs in bean (Phaseolus vulgaris L.) root nodule cells infected with either the wild-type or a C4-dicarboxylic acid mutant strain of Rhizobium leguminosarum bv. phaseoli. In effective nodules, where fixation of atmospheric dinitrogen is taking place, HRGPs were found to accumulate mainly in the walls of infected cells and in peribacteroid membranes surrounding groups of bacteroids. Internal ramifications of the peribacteroid membrane were also enriched in HRGPs whereas the peribacteroid space as well as the bacteroids themselves were free of these glycoproteins. In mutant-induced root nodules, HRGPs were specifically associated with the electron-dense, laminated structures formed in plastids as a reaction to infection by this mutant. The presence of HRGPs was also detected in the host cytoplasm. The aberrant distribution of HRGPs in infected cells of mutant-induced nodules likely reflects one aspect of the altered host metabolism in relation to peribacteroid-membrane breakdown. The possibility that the antiserum used for HRGP localization may have cross-reacted with ENOD 2 gene products is discussed in relation to amino-acid sequences and sites of accumulation. 相似文献
88.
89.
Hubert F. Loyke 《Biological trace element research》1991,29(1):45-49
The role of the trace minerals, copper (Cu) and zinc (Zn) are important in maintaining blood pressure. Copper has been found to inhibit the activity of angiotensin's converting enzyme. An interrelationship has been found to exist between Cu and Zn. Data in renal (RH) and spontaneous hypertensive rates (SHR) regarding Cu and Zn is lacking. The purpose of this report was to measure Cu and Zn levels in two types of experimental animal models of hypertension compared to normotensive (NT) rats. Blood samples were drawn to measure serum levels of Cu and Zn in three types of animals, RH, SHR, and NT. Serum Cu values were found to be lower, whereas Zn levels were elevated in the SHR animals. Serum levels of Cu and Zn in the RH animals were similar to those found in the NT animals. Further study of the interaction of those trace minerals is documented, and extends over knowledge of the role of minerals in blood pressure control. 相似文献
90.
The initial (F0), maximal (FM) and steady-state (FS) levels of chlorophyll fluorescence emitted by intact pea leaves exposed to various light intensities and environmental conditions, were measured with a modulated fluorescence technique and were analysed in the context of a theory for the energy fluxes within the photochemical apparatus of photosynthesis. The theoretically derived expressions of the fluorescence signals contain only three terms, X=J2p2F/(1–G), Y=T/(1–G) and V, where V is the relative variable fluorescence, J2 is the light absorption flux in PS II, p2F is the probability of fluorescence from PS II, G and T are, respectively, the probabilities for energy transfer between PS II units and for energy cycling between the reaction center and the chlorophyll pool: F0=X, FM=X/(1–Y) and FS=X(1+(YV/(1–Y))). It is demonstrated that the amplitudes of the previously defined coefficients of chlorophyll fluorescence quenching, qP and qN, reflect, not just photochemical (qP) or nonphotochemical (qN) events as implied in the definitions, but both photochemical and nonphotochemical processes of PS II deactivation. The coefficient qP is a measure of the ratio between the actual macroscopic quantum yield of photochemistry in PS II (41-1) in a given light state and its maximal value measured when all PS II traps are open (41-2) in that state, with 41-3 and 41-4. When the partial connection between PS II units is taken into consideration, 1-qP is nonlinearily related to the fraction of closed reaction centers and is dependent on the rate constants of all (photochemical as well as nonphotochemical) exciton-consuming processes in PS II. On the other hand, 1-qN equals the (normalized) ratio of the rate constant of photochemistry (k2b) to the combined rate constant (kN) of all the nonphotochemical deactivation processes excluding the rate constant k22 of energy transfer between PS II units. It is demonstrated that additional (qualitative) information on the individual rate constants, kN-k22 and k2b, is provided by the fluorescence ratios 1/FM and (1/F0)–(1/FM), respectively. Although, in theory, 41-5 is determined by the value of both k2b and kN-k22, experimental results presented in this paper show that, under various environmental conditions, 41-6 is modulated largely through changes in k
N, confirming the idea that PS II quantum efficiency is dynamically regulated in vivo by nonphotochemical energy dissipation.Abbreviations Chl
chlorophyll
- F0, FM and FS
initial, maximal and steady-state levels of modulated Chl fluorescence emitted by light-adapted leaves
- PS I and II
photosystem I and II
- qP and qN
(previously defined) photochemical and nonphotochemical components of Chl fluorescence quenching 相似文献