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141.
The spontaneous conversion of mammalian cyclic GMP-dependent protein kinase (G-PK) into modulator-dependent protein kinase (type II) (M-PKII) in the absence of cGMP or histone was observed in vitro. The findings, together with similarity in substrate protein specificity, suggest that M-PKII is the catalytic subunit of mammalian G-PK. 相似文献
142.
Summary Silver-staining has been used to identify the nucleolus organizer regions (NORs) in the bharal. These show homology with sheep, goat, cattle and aoudad. The association of the NORs on both telomeres of chromosome 3 results in a ring chromosome. 相似文献
143.
Summary We analyzed inheritance of 5Es-1 alleles inP. leucopus and found them to be co-dominant and segregating from a single autosomal locus, thereby verifying assumptions of Mendelian inheritance imfield data. We also described an allele that is silent in hemolysate, but is active in liver extract.Acknowledgment. Laboratory analysis was partially supported by a grant-in-aid (No. 0171-02-240-76) to Kaufman from the Research Foundation of State University of New York. 相似文献
144.
J. Kędziora M. Soszyński G. Bartosz H. Witas W. Leyko 《Cellular and molecular life sciences : CMLS》1980,36(8):926-927
Summary A statistically significant decrease of prealbumin and statistically significant increases of alpha2-macroglobulin and IgA were found in blood plasma of patients with Down's syndrome using quantitative crossed immunoelectrophoresis.We are indebted to Prof. T.C. Bøg-Hansen, University of Copenhagen, for the helpful discussion of our results. 相似文献
145.
W. D. MacRae G. F. Q. Chan Chi-Kit Wat G. H. N. Towers J. Lam 《Cellular and molecular life sciences : CMLS》1980,36(9):1096-1097
Summary -Terthienyl and 5 polyacetylenes were examined for chromosome damaging activity using Syrian hamster cells. None of these naturally occurring compounds induced sister chromatid exchanges and neither -terthienyl nor phenylheptatriyne induced chromosome aberrations.The authors wish to thank the National Science and Engineering Research Council for financial support of this research. 相似文献
146.
Summary Prostaglandins (PGs) E2, F2, and I2 were examined for their effects on the electrical and mechanical activities of isolated rat, rabbit and guinea-pig hearts. All PGs produced dysrhythmias in rat hearts at low concentrations only, while higher concentrations were antiarrhythmic. Guinea-pig hearts were less responsive while rabbit hearts were completely resistant.We thank the Manitoba Heart Foundation for financial support and Dr J. Pike (Upjohn, Kalamazoo, MI, USA) for gifts of prostaglandins. Dr M. Karmazyn is a Fellow of the Canadian Heart Foundation. 相似文献
147.
Summary The karyotype of the pampas fox has 2n=74 and a NF=76. Except forChrysocyon brachyurus, 2n=74 is a common diploid number for the South American Canidae. This number is higher than in theVulpes group and lower than in the group of the typicalCanis. No marker chromosomes are present in the South American Canidae. 相似文献
148.
C. R. Pace-Asciak N. S. Edwards M. C. Carrara 《Cellular and molecular life sciences : CMLS》1980,36(6):635-637
Summary Tritium-labelled PGF2 was administered i.v. into rats of varying ages (2, 4, 6 weeks and adult). Urine was collected and assayed for radioactive products by thin-layer-chromatography. Results showed a distinctly different urinary profile between the 2-week-old and the adult rat. While the urinary pattern from the 2-week-old rat gave a single less polar product than PGF2, the pattern from the adult rat gave products more polar than PGF2. Urine from the 4- and 6-week-old rats gave a mixture of these types of products. These results indicate that some prostaglandin catabolic pathway (likely the -oxidative system) is activated in vivo within the 4–6-week postnatal period in the rat.Supported by a grant (MT-4181) to C.P.-A. from the Medical Research Council of Canada.This study is in partial fulfillment of the requirements for a Ph.D. degree in the Department of Pharmacology, University of Toronto. 相似文献
149.
150.
Summary Autoradiographic, stereological and histological studies have been carried out to determine the origin of muscle fibre splitting which supposedly occurs during muscle hypertrophy. The results obtained clearly indicate that the supposedly split fibres are a transient response probably derived from satellite cells and are not derived from pre-existing fibres by true splitting. Similarly, increases in muscle fibre size are not achieved by recruitment of satellite structures as indicated by lack of myonuclear recruitment.Acknowledgment. This work was carried out with the aid of a grant from the Medical Research Council of Great Britain. The authors are grateful for the excellent technical assistance of Miss H. Caulton, M.J. Wild and M. Fenner. 相似文献