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1,3-Propanediol (PAD) was fed to rats for 15 weeks, and its effects on hepatic and testicular DNA were studied. The control rats were fed a casein-based diet that contained 10% tocopherol-stripped corn oil with 30 IU of d,l-α-tocopherol acetate/kg; the experimental rats were fed the same diet with 500 ppm of PAD. Homogenates prepared from the livers of each group of rats converted 1,3-propanediol to malondialdehyde (MDA) with equal efficacy, but homogenates of testes did not catalyze this conversion. After 10–15 weeks of feeding the diets, the hepatic DNA of the rats fed PAD had less template activity, more bound tryptophan and more DNA-protein and interstrand DNA cross-links than that of the control rats. As measured by template activity and bound tryptophan, testicular DNA of the experimental rats was not different from that of the control rats; however, there was slightly more cross-linking in the testicular DNA of experimental rats than in that of control rats. Testes of the experimental rats contained more lipid-soluble fluorophores than did those of the control rats. The results are consistent with the conclusion that PAD was converted to MDA in vivo and that MDA is the reactive species that caused the observed biological damage. 相似文献
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A note on antibiotic-resistant Escherichia coli in adult man, raw sewage and sewage-polluted River Tigris in Mosul, Nineva 总被引:2,自引:1,他引:1
A total of 600 isolates of Escherichia coli were isolated, over a 9 month period during 1984, from healthy human adults, raw sewage and the sewage-polluted River Tigris in Nineva. Over 90% of these organisms were E. coli type 1, but only 8.3% could be serogrouped as enteropathogenic E. coli . Resistance of these organisms to 11 antimicrobial drugs was assessed. Over 40% were antibiotic-resistant and of these 77.1% were resistant to more than one antibiotic. The minimal inhibitory concentration of ampicillin for 193 selected strains from the various sources was determined and ranged from <0.625- > 160 μg/ml. The high incidence of antibiotic-resistant E. coli in this locality and the possible implications to human health are discussed. 相似文献
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K H?kkinen M Alén P V Komi 《European journal of applied physiology and occupational physiology》1984,53(2):97-105
Various aspects of neuromuscular, anaerobic, and aerobic performance capacity were investigated in four powerlifters, seven bodybuilders, and three wrestlers with a history of specific training for several years. The data (means +/- SD) showed that the three subject groups possessed similar values for maximal isometric force per unit bodyweight (50.7 +/- 9.6, 49.3 +/- 4.1, and 49.3 +/- 10.9 N/kg, respectively). However, significant (P less than 0.05) differences were observed in the times for isometric force production, so that e.g., times to produce a 30% force level were shorter for the wrestlers and bodybuilders (28.3 +/- 3.1 and 26.4 +/- 6.6 ms) than that (53.3 +/- 23.7 ms) for the powerlifters. Utilization of elastic energy by the wrestlers was significantly (P less than 0.05) better than that of the other two subject groups, as judged from differences between the counter-movement and squat jumps at 0, 40, and 100 kg's loads. No differences were observed between the groups in anaerobic power in a 1-min maximal test, but the values for VO2 max were higher (P less than 0.05) among the wrestlers and bodybuilders (57.8 +/- 6.6 and 50.8 +/- 6.8 ml X kg-1 X min-1) as compared to the powerlifters (41.9 +/- 7.2 ml X kg-1 X min-1). Within the limitations of the subject sample, no differences of a statistical significancy were observed between the groups in fibre distribution, fibre areas, or the area ratio of fast (FT) and slow (ST) twitch fibres in vastus lateralis.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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In order to understand the coordinate regulation between the alpha-like and beta-like globins during the developmental switches in hemoglobin synthesis, we have studied the rabbit alpha-like globin gene family. A cluster of six linked genes arranged 5'-zeta 1-alpha 1-theta 1-zeta 2-zeta 3-theta 2-3' has been isolated as a set of overlapping clones from a library of rabbit genomic DNA. Blot-hybridization analysis of genomic DNA not only confirms this linkage arrangement but also reveals the presence of additional zeta and theta genes. We propose that this gene cluster was generated by a block duplication of a set of alpha-like genes; the proposed duplication unit is zeta-zeta-alpha-theta. Further duplications of a zeta-zeta-theta set are also proposed to have occurred. As expected for a duplicated locus, the rabbit alpha-like gene cluster contains long blocks of internal homology. The Z homology block is about 7.2 kilobase pairs long and contains the zeta genes; the T homology block is about 4.7 kilobase pairs long and contains a theta gene. Surprisingly, both Z and T homology blocks are flanked by a common junction sequence (J) which contains a region very similar to the 3'-untranslated sequence of an alpha-globin gene. Analysis of the J sequences suggests a recombination mechanism by which the alpha gene could have been deleted from the second set of genes in the cluster (zeta 2-zeta 3-theta 2). The relationships among the genes in characterized alpha-like gene clusters in mammals are summarized. The rabbit gene cluster differs from those of other mammals principally in the loss of a gene orthologous to the human psi alpha 1 and in the block duplication of the zeta-zeta-alpha-theta gene set. 相似文献
7.
Extraocular muscle motoneurones were localised in the oculomotor nucleus (ON), trochlear nucleus (TN) and abducens nucleus (AN) in the marmoset brain using the horseradish peroxidase (HRP) retrograde labelling technique. HRP pellets injected into individual extraocular muscles revealed one or more groups of labelled neurones occupying discrete loci within these nuclei. Relatively little overlap of motoneurone pools was observed, except in the case of the inferior oblique and superior rectus muscles. Injections of HRP into the medial rectus muscle revealed three separate populations of labelled cells in the ipsilateral ON. Motoneurones innervating the inferior rectus muscle were mainly localised in the lateral somatic cell column of the ipsilateral ON. A second smaller grouping was observed in the medial longitudinal fasciculus. The inferior oblique muscle motoneurones were localised in the ipsilateral medial somatic cell column intermingled with motoneurones supplying the superior rectus muscle of the opposite eye. The superior oblique muscle motoneurones occupied the entire TN and the lateral rectus muscle motoneurones the AN. It was concluded that the organisation of nuclei and subnuclei responsible for controlling the extraocular muscles in the marmoset is broadly similar to that of other primates. 相似文献
8.
Blood lymphocytes in culture were irradiated by gamma-rays 3 h to 30 mn before harvesting. The various induced lesions were analysed, with a particular attention on sticky chromosomes, i.e. radial figures in which chromosomes are not obviously broken, but are linked by a tiny filament. Such anomalies are preferentially induced in mid to late G2-phase. They result from recombinations occurring at nonrandom chromosome regions: junction between hetero- and euchromatin, and telomeric regions. It is proposed that they are formed when double strand breaks are induced while intrachromatidic links have started to be formed in the course of chromosome condensation. If this interpretation is correct, the apparent lack of induced breakage of premitotic chromosomes is artifactual. 相似文献
9.
J. L. Tolmie E. Boyd P. Batstone M. E. Ferguson-Smith L. Al Roomi J. M. Connor 《Human genetics》1988,80(2):197-200
Summary We report male and female siblings with extreme microcephaly and mental retardation, growth retardation, and multiple chromosome mosaicism. Mental retardation associated with chromosome mosaicism does not always carry a low recurrence risk. 相似文献
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