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991.
Loss of a Harvey ras allele in sporadic Wilms' tumour 总被引:5,自引:0,他引:5
A E Reeve P J Housiaux R J Gardner W E Chewings R M Grindley L J Millow 《Nature》1984,309(5964):174-176
Genomic changes within chromosome band 11p13 appear to have a role in the initiation of Wilms' tumour. The human Harvey ras oncogene, c-Ha-ras 1, has been located by Jhanwar et al. immediately adjacent to this region at band 11p14 .1, although several groups have assigned the gene more distally at band 11p15 . We have examined tumour DNA from two cases of sporadic Wilms' tumour, and report here that in both cases one of the two constitutional c-Ha-ras 1 alleles was absent. One tumour had a reciprocal translocation between the short arm of chromosome 11 (at band 11p13), and the long arm of chromosome 12, with no visible loss of chromosomal material. The loss of a c-Ha-ras 1 allele in association with this translocation indicates that a submicroscopic deletion had occurred. The resulting hemizygosity may have had a role in tumour initiation. Our results indicate that the c-Ha-ras 1 gene and the 'Wilms' tumour locus' may be in close proximity. It would, therefore, be premature to exclude the possibility that these two sites are functionally related. 相似文献
992.
Charged groups play a critical role in the stability of the helix formed by the isolated C-peptide (residues 1-13 of ribonuclease A) in aqueous solution. One charged-group effect may arise from interactions between charged residues at either end of the helix and the helix dipole. We report here that studies of C-peptide analogues support the helix dipole model, and provide further evidence for the importance of electrostatic interactions not included in the Zimm-Bragg model for alpha-helix formation. 相似文献
993.
E. San Miguel Salán 《Cellular and molecular life sciences : CMLS》1984,40(8):861-862
Summary Samples from 4 populations ofD. melanogaster were treated with formaldehyde by the larval feeding method, and induced lethality was scored. The results showed relevant differences among the populations analyzed. 相似文献
994.
E. Muzii 《Cellular and molecular life sciences : CMLS》1982,38(5):562-563
Summary The hemolymph ofPatella is yellow and contains 30–300 μg/ml of iron. Ferritin was found to be uniquely abundant in the hemolymph, and was identified
by electron microscopy and electrophoresis. Electrophoretically it appears to be heterogeneous, with an individually variable
number of components with very similar mobilities. Ferritin in the blood of limpets might relate to the turnover of radular
denticles. 相似文献
995.
996.
Summary Stimulation of aminopyrine demethylation induced in rats by oral or i.p. administration of phenobarbital was partially inhibited in animals receiving daily treatments of 2×200 mg/kg gum Arabic p.o. 相似文献
997.
Retroviral antigens on gs- chf- leukocytes 总被引:1,自引:0,他引:1
It has recently been suggested that the endogenous retroviruses present in many different species might be involved during stimulation of the immune system of their hosts. We have now studied the expression of two avian retroviral antigens p27 and gp85 in chicken lymphoid cells by indirect immunofluorescence (IIF) and by complement-dependent microcytotoxicity (CDM). We have now found that these viral antigens are expressed in peripheral blood leukocytes of adults and embryos and in splenic and bursal lymphocytes of Spafas gs- chf- chickens but they are not expressed in fibroblasts cultured from the feather follicles of the same individual adult birds nor in fibroblasts cultured from embryos of the same flock. The differential expression of viral antigens in leukocytes may be related to a specific property or function of these cells. 相似文献
998.
999.
1000.
Zusammenfassung In 2 von 7 Stämmen vonProteus rettgeri gelang die Induktion von Bakteriozinen unter der Einwirkung von Mitomycin C. Die gewonnenen Bakteriozine waren chloroformbeständig, trypsinresistent und hitzelabil. 相似文献