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11.
Brian Rodrigues Michael R. Spooner David L. Severson 《Molecular and cellular biochemistry》1992,116(1-2):33-37
An exogenous [3H]triolein emulsion was hydrolyzed by intact cardiac myocytes with functional LPL located on the cell surface. This surface-bound LPL could be released into the medium when cardiac myocytes were incubated with heparin. Incubation of cardiac myocytes with VLDL, or the products of TG breakdown, oleic acid or 2-monoolein, did not increase LPL activity in the medium. However, incubation of cardiac myocytes with either VLDL or oleic acid for > 60 min did reduce heparin-releasable LPL activity. In the heart, this inhibitory effect of FFA could regulate the translocation of LPL from its site of synthesis in the cardiac myocyte to its functional site at the capillary endothelium.Abbreviations LPL
lipoprotein lipase
- TG
triacylglycerol
- FFA
free fatty acids
- VLDL
very-low density lipoprotein 相似文献
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C. Rodrigues 《Human Evolution》1991,6(5-6):451-459
The relative sizes of the brain stem, cerebellum, diencephalon, archicertex and neocortex were investigated in twenty brains
of each sex, by determining the percentages of average total brain weights in each case. The differences between the left
and the right cortical regions were also compared.
The neo-archicortical ratio was found to be smaller in females than in males. Significantly heavier right neocortex occurred
in males than in females. Weight predominance of the right archicortex was found in both sexes.
These findings are suggestive that anatomical differences may contribute to the behaviour pattern differences occurring between
male and female. 相似文献
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It has been shown that differentiated derivatives of retinoic acid (RA)-treated F9 embryonal carcinoma cells become non-malignant. In the present study it is asked whether this loss of malignancy is due to cellular differentiation. Because the ability of cells to grow in suspension correlates with in vivo tumorigenicity, we determined the time course of the loss of this property, after RA treatment, with relation to the differentiation to parietal endoderm and the acquisition of normalcy in several common transformation-specific properties of F9 cells. Our results show that pretreatment with RA for 24 h caused 80% inhibition of anchorage-independent growth in F9 cells, and this inhibition reached its highest level (98%) after pretreatment with RA for 48 h and longer. However, all other observed transformation-related properties, and the levels of plasminogen activator (marker for parietal endoderm) remained unaltered at this early post-treatment stage. These observations suggest that the loss of malignancy is a relatively early event in the biochemical pathways involved in the RA-induced differentiation of F9 cells. Furthermore, our data show that the presence of elevated levels of p53 alone may not be sufficient to maintain the anchorage-independent growth and the rapid proliferation of F9 cells. 相似文献
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A. S. Rodrigues Pereira 《Planta》1968,80(4):349-358
Summary Staminate flowers of the Acorn squash (Cucurbita pepo, cv. Table Queen) are initiated monosexually, pistillate flowers are initiated bisexually. Pistillate flower primordia are physiologically bisexual from a stage below 0.3 mm until they are 0.8 mm in width.Male and female floral buds were cultivated on White's medium, modified according to Galun et al. (1963). In excised female floral buds the relative development of stamens is better than in in-situ floral buds; the opposite relationship holds for ovary development. The smaller the bud at excision, the greater the stamen growth and the lesser the ovary growth, both in absolute and relative terms. Although smaller pistillate floral buds cultured in vitro showed a greater increase in maleness than larger ones, there was no difference in the percentage of female buds between explants of the two sizes when originating from the mixed stem region (that is, the stem region carrying male and female flowers). Addition of 3-indoleacetic acid and the anti-auxin p-chlorophenoxyisobutyric acid to standard medium in equal amounts resulted in somewhat better development of excised floral buds than addition of each of these compounds alone.The percentage of female buds among explants originating from identical nodes was not significantly influenced by 3-indoleacetic acid or p-chlorophenoxyisobutyric acid.Weizmann Memorial Fellow. The studies reported in this publication were mainly undertaken at the Weizmann Institute of Science 相似文献
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Chromosomal polymorphism regarding number of NOR sites in the cyprinid fish Chondrostoma lusitanicum was examined using C-banding, silver-staining (Ag), and fluorescent staining with chromomycin A3 (CMA3). The analysis of heterochromatic regions allowed a more precise identification of the centromeric regions and the proposal of a revised haploid chromosome formula (7M: 15S: 3A). We describe variability in the number of NOR regions per genome, number of active NOR sites per cell, and relative size of individual NORs. Individuals expressed two or four NOR-bearing chromosomes. Polymorphism was detected in all the populations studied and sex-related differences were not found. The observed chromosomal NOR phenotypes suggest the occurrence of structural rearrangements during the evolutionary process of this diploid leuciscine cyprinid. 相似文献