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121.
The effect of continuous-wave ultrasound on the chromosomes of newborn infants has been investigated. Twenty-four women were studied during labour. The fetal heart was monitored by a Sonicaid FM2 monitor applied to the abdomen, and continuous monitoring undertaken for intervals varying from 1 hour 5 minutes to 9 hours 25 minutes. There was no increase in the number of chromosome aberrations in cultures of blood taken from the insonated babies when compared with controls. 相似文献
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Studies on the subunit structure and amino acid sequence of triose phosphate isomerase from chicken breast muscle 下载免费PDF全文
1. Triose phosphate isomerase was prepared by chromatography on DEAE-cellulose of an (NH(4))(2)SO(4) fraction of an extract of homogenized chicken breast muscle. The product is homogeneous on gel electrophoresis and is suitable for growing crystals for X-ray work. The specific activity is 10000 units/mg and the value for E(0.1%) (280) is 1.20. 2. Comparison between the sum of the amino acid compositions of the tryptic peptides of the protein and the amino acid composition obtained on total hydrolysis of the protein indicates that the relative subunit mass is about 27000. 3. These data, together with the results of the examination of the amino acid compositions of a number of minor peptides, the number of peptides in the tryptic digest and the complete amino acid sequences of the tryptic peptides (the determination of which is described here), give no indication that the subunits are dissimilar. 4. A tentative amino acid sequence is presented for the protein, in which the ordering of the tryptic peptides is derived by homology with the sequence of the rabbit muscle enzyme (Corran & Waley, 1973). 5. An appendix describes the use that was made of mass spectrometry in the determination of some of the sequences. Mass-spectrometric data have been obtained for 35 residues, that is about 15% of the total sequence of the protein. 6. An extended version of the present paper has been deposited as Supplementary Publication SUP 50025 at the British Library, Lending Division (formerly the National Lending Library for Science and Technology), Boston Spa, Yorks. LS23 7BQ, U.K., from whom copies may be obtained on the terms given in Biochem. J. (1973) 131, 5. 相似文献
125.
This report presents results in the composition of major carotenoids of various coloured mutants of the genusRhodotorula and of mating types of the genusRhodosporidium. The separation of carotenoid intermediates was carried out by thin layer chromatography using Silufol 254 Kavalier and the determination of eluated spots by spectrophotometry. There was found no difference in carotenoid composition of both mating typesa and α of individual species of the genusRhodosporidium. The vegetative and sexual reproduction ofRhodotorula andRhodosporidium can be separated from the carotenogenesis using 10?4 mol diphenylamine. It was concluded that lycopene could be the intermediate to mono- and dicyclic carotenoids; in the case of partial inhibition of the dehydrogenation step the direct cyclization of neurosporene to β-zeacarotene can be expected. An unknown compound, probably lycopersene was found and was considered to be the precursor of phytoene. Phytoene and phytofluene were proved in all studied samples. Nutritional conditions (vitamins, sulfur amino acids, etc.) are able to shift the ratios between major carotenoids. Rhodotorula aurantiaca strains were observed to be auxotrophic mutants of various characters and the existence of this species as independent one, was denied. 相似文献
126.
Male Leeds rats were fed a diet containing 0.05% of the non-carcinogen 4-acetylaminofluorene (4-AAF) for 8–10 months. They were then returned to a normal diet and their pancreatic tissues examined by electron microscopy at intervals between 2 and 12 months after the end of 4-AAF treatment. 4-AAF was found to induce a persistent alteration in the morphology of the granular endoplasmic reticulum, involving distortion and dilatation of the cisternae. In some respects this lesion resembles that which is induced by the carcinogenic isomer, 2-acetylaminofluorene (2-AAF). 相似文献
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Anna Chrtková-Žertová 《Folia Geobotanica》1969,4(3):303-311
In der ArtVicia sepium L. kann man in Mitteleuropa und in südlichen Teilen von Nordeuropa drei Varietäten unterscheiden: 1. var.sepium mit breiten Blättchen und einem kahlen bis angedrückt behaarten Kelch, 2. var.montana Koch mit schmalen Blättchen und einem kahlen oder zerstreut angedrückt behaarten Kelch, und 3. var.eriocalyx ?elak. mit breiten bis mittelbreiten Blättchen und einem abstehend langbehaarten Kelch, noch mit einer niedrigen und einer hohen Wuchsform. Bei allen Proben wurde die Chromosomezahl 2n=14 festgestellt. 相似文献
129.
Anna Chrtková-Žertová 《Folia Geobotanica》1970,5(1):89-97
Lotus krylovii Schischk. etSerg. undL. corniculatus L. subsp.frondosus Freyn sind zwei unterschiedliche Taxa, gekennzeichnet durch einige morphologische Merkmale.L. krylovii ist am nächsten mitL. tenuis Waldst. etKit. verwandt;L. corniculatus subsp.frondosus gehört in den Umkreis der Unterart vonL. corniculatus L., die im östlichen Teil des Areals der Art verbreitet ist. Nach ihrer Haupt-Verbreitung gehören die beiden Taxa zu den westasiatischen Arten. 相似文献
130.