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61.
A minority of 46,XX true hermaphrodites are positive for the Y-DNA sequence including SRY 总被引:4,自引:0,他引:4
Ken McElreavey Raphaël Rappaport Eric Vilain Nacer Abbas François Richaud Stéphen Lortat-Jacob Roland Berger Maryvonne LeConiat Chafika Boucekkine Kiran Kucheria Samia Temtamy Claire Nihoul-Fekete Raja Brauner Marc Fellous 《Human genetics》1992,90(1-2):121-125
Summary A total of 30 cases of 46,XX true hermaphroditism was analysed for Y-DNA sequences including the recently cloned gene for male testis-determination SRY. In 3 cases, a portion of the Y chromosome including SRY was present and, in 2 cases, was localised, to Xp22 by in situ hybridisation. Since previous studies have shown that the majority of XX males are generated by an X-Y chromosomal interchange, the Xp22 position of the Yp material suggests that certain cases of hermaphroditism can arise by the same meiotic event. The phenotype in the 3 SRY-positive cases may be caused by X-inactivation resulting in somatic mosaicism of testis-determining factor expression giving rise to both testicular and ovarian tissues. Autosomal or X-linked mutation(s) elsewhere in the sex-determining pathway may explain the phenotype observed in the remaining 27 SRY-negative cases. 相似文献
62.
More than 750 plants were regenerated from protoplasts isolated from microspore callus-derived cell suspensions of the Mediterranean japonica rice Miara, using a nurse-feeder technique and N6-based culture medium. The mean plating efficiency and the mean regeneration ability of the protocalluses were 0.5% and 49% respectively. Flow cytometric evaluation of the DNA contents of 7 month old-cell and protoplast suspensions showed that they were still haploid. Contrastingly, the DNA contents of leaf cell nuclei of the regenerated protoclones ranged from 1C to 5C including 60% 2C plants. This was consistent with the morphological type and the fertility of the mature plants. These results and the absence of chimeric plants suggest that polyploidization occurred during the early phase of protoplast culture.Abbreviations BAP
6-benzylamino purine
- 2,4-D
2,4-dichlorophenoxyacetic acid
- FDA
fluorescein diacetate
- GA3
gibberellic acid
- NAA
-naphthaleneacetic acid
- PAS
periodic acid Schiff
- PCM
protoplast culture medium
- PCV
packed cell volume 相似文献
63.
S Cíkos S Kuchár J Koppel 《Physiological research / Academia Scientiarum Bohemoslovaca》1992,41(5):387-392
The influence of estradiol and testosterone on body growth of young male Wistar rats was investigated. In the first experiment, estradiol was given to intact ad libitum fed male rats at 32, 37 and 42 days of age. Moreover, two untreated groups of animals were used: one was fed restrictedly according to the food intake of animals receiving estradiol and another was fed ad libitum. The animals were sacrificed at 47 days of age. Both untreated groups of animals achieved significantly higher body weight and length of tibia than estradiol treated animals. Also the growth of the tail of untreated animals was more intensive than that of estradiol treated animals. In the second experiment, estradiol was given to intact ad libitum fed male rats at 30, 35 and 45 days of age. Moreover, testosterone was given to a half of these animals at 45, 50 and 55 days of age. The animals were sacrificed at 60 days of age. Administration of testosterone significantly increased the growth of the tail and tibia in comparison to the animals which did not receive testosterone after estradiol administration. The results of the present study show that the inhibitory effect of estradiol on body growth of young male rats is not only the result of decreased food intake and that testosterone can improve the skeletal growth of male rats altered by previously given estradiol. 相似文献
64.
Robert G. Rutledge Thérèse Quellet Jiro Hattori Brian L. Miki 《Molecular & general genetics : MGG》1991,229(1):31-40
Summary The Brassica napus rapeseed cultivar Topas contains an acetohydroxyacid synthase (AHAS) multigene family consisting of five members (AHAS 1–5). DNA sequence analysis indicate that AHAS1 and AHAS3 share extensive homology. They probably encode the AHAS enzymes essential for plant growth and development. AHAS2 has diverged significantly from AHAS1 and AHAS3 and has unique features in the coding region of the mature polypeptide, transit peptide and upstream non-coding DNA, which raises the possibility that it has a distinct function. AHAS4 and AHAS5 have interrupted coding regions and may be defective. The complexity of the AHAS multigene family in the allotetraploid species B. napus is much greater than reported for Arabidopsis thaliana and Nicotiana tabacum. Analysis of the presumptive progenitor diploid species B. campestris and B. oleracea indicated that AHAS2, AHAS3 and AHAS4 originate from the A genome, whereas AHAS1 and AHAS5 originate from the C genome. Further variation within each of the AHAS genes in these species was found. 相似文献
65.
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
66.
Thérèse E. Malliavin Marc A. Delsuc Jean Y. Lallemand 《Journal of biomolecular NMR》1992,2(4):349-360
Summary The structural determination of biological molecules in solution by NMR relies on the determination of a set of interatomic distances obtained by measurement of intramolecular nuclear Overhauser effects (NOE). It is shown in this paper that it is possible to obtain the accurate relaxation rate (and hence the interatomic distance) from the direct measurement of a single NOE signal. The precise analysis of a NOESY peak evolution with respect to the mixing time allows the evaluation of the relaxation parameters for the pair of spins under consideration. This is done without any assumption on the relaxation of unmeasured spins, or on the movement of the molecule. The theoretical basis of this method is presented. In order to evaluate the proposed method, a simulated case on the protein BPTI is studied, which shows that the method performs very well even in the case of noisy data sets. 相似文献
67.
In the past year, additional experimental data have expanded our understanding of the molecular mechanisms that underlie nuclear receptor control of regulatory programs. It is increasingly clear -that steroid members (e.g. glucocorticoid and estrogen) and non-steroid members (e.g. retinoic acid, thyroid hormone, and vitamin D) of the nuclear receptor superfamily may utilize distinct strategies in achieving their complex control of gene regulation. 相似文献
68.
69.
L V Krasheninnikova G V Rassadina S N Kirsanova L M Khromova V M Iusibov I r Pak Chun V M Andrianov E S Piruzian 《Molekuliarnaia genetika, mikrobiologiia i virusologiia》1991,(11):17-20
The genetic constructions based on integrative vector pGV3850 were used to introduce bacterial genes xyl and T-cyt into potato cells. The transformation was carried out using the leaf-disc method with modifications. A special system for obtaining regenerants from explants of potato in vitro plants or calli has been designed that permitted the selection of transgenic shoots. The presence of the genes in potato genome has been proved by testing the NPTII and glucoisomerase activities. The transgenic plants expressing T-cyt gene differed from the wild type in sharp decrease of the apical dominance. 相似文献
70.
Data in the literature concerning the role of macrophages in anaphylaxis are contradictory. In the present study the effect of macrophage blockade induced by gadolinium chloride (GdCl3) on anaphylactic shock was investigated. Our observations show that GdCl3 prevents the lethal anaphylactic shock of mice sensitized to ovalbumin. GdCl3 given i.v. in a dose of 1 mg/100 g body weight 24 or 48 h before the elicitation of anaphylactic shock resulted in 90% survival, compared to the 43% survival in the control group. The same dose of this rare earth metal salt also greatly reduced the mortality in mice sensitized with ovalbumin containing Bordetella pertussis vaccine, and the symptoms of anaphylaxis including the accumulation of 5-hydroxytryptamine in the liver. Our results suggest that macrophages play an important role in anaphylaxis. 相似文献