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81.
Anna Carmen Borrione Anna Maria Cecilia Zanellato Leopoldo Saggin Manuela Mazzoli Giuseppe Azzarello Saverio Sartore 《Differentiation; research in biological diversity》1988,38(1):49-59
Myosin heavy chain (MHC) composition of chemically-induced rhabdomyosarcoma (RMS) was analyzed by gel electrophoresis and Western blotting using a panel of monoclonal antimyosin antibodies specific for embryonic-, neonatal-, slow- and adult fast-type MHC isoforms. Myosin extracted from tumours and electrophoresed on 6%-sodium dodecyl sulfate (SDS)glycerol gels was found to migrate as three distinct MHC components. These polypeptides were present in different relative amounts in the five RMS studied. Western blotting experiments revealed that variable proportions of embryonic-, slow- and adult fast-, but not neonatal-type, MHC isoforms are consistently expressed in RMS. Indirect and double immunofluorescence procedures applied to cryosections of tumoral tissue showed that: (a) RMS cells were unreactive with antineonatal-type-MHC antibody, (b) the majority of neoplastic, desmin-positive, cells contained embryonic- as well as adult fast-type MHCs and (c) a minority of cells were labelled by anti-slow MHC antibody. The results of this study indicate that there is no obligatory sequence of MHC isoform expression in the molecular transition (emb----neo----adult) which occurs during rat skeletal myogenesis. 相似文献
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83.
Leopoldo Villegas 《生物化学与生物物理学报:生物膜》1982,685(3):249-252
The asymmetry of the osmotic response of the frog gastric mucosa has been further analyzed by studying the effect of external tonicity changes on the water diffusion fluxes. Hyperosmotic solution at the serosal surface does not affect the water diffusion fluxes. Hyperosmotic solution at the mucosal surface, with isosmotic solution at the serosal surface, significantly reduces (P<0.001) the serosal-to-mucosal and the mucosal-to-serosal water diffusion. An increment in the restriction offered by the mucosa to water diffusion by effect of hypertonicity at the mucosal surface is proposed. 相似文献
84.
Martha Beatriz Moreno Luis Concha Leopoldo González-Santos Juan Jose Ortiz Fernando Alejandro Barrios 《PloS one》2014,9(8)
We assessed the relationship between structural characteristics (area) and microstructure (apparent diffusion coefficient; ADC) of the corpus callosum (CC) in 57 healthy children aged 7.0 to 9.1 years, with diverse cognitive and academic abilities as well as executive functions evaluated with a neuropsychological battery for children. The CC was manually delineated and sub-segmented into six regions, and their ADC and area were measured. There were no significant differences between genders in the callosal region area or in ADC. The CC area and ADC, mainly of anterior regions, correlated with different cognitive abilities for each gender. Our results suggest that the relationship between cognitive abilities and CC characteristics is different between girls and boys and between the anterior and posterior regions of the CC. Furthermore, these findings strenghten the idea that regardless of the different interhemispheric connectivity schemes per gender, the results of cognitive tasks are very similar for girls and boys throughout childhood. 相似文献
85.
Leopoldo Villegas 《生物化学与生物物理学报:生物膜》1983,735(1):35-39
Serosal-to-mucosal and mucosal-to-serosal diffusion of 14C-labelled inulin, sucrose, erythritol and propionamide was compared with 3HHO diffusion in mucosae incubated with isosmotic solutions at both surfaces, as well as isosmotic solution at serosal surface and hyperosmotic solution at the mucosal surface. The use of a hyperosmotic solution at the mucosal surface significantly increases unidirectional diffusion fluxes of inulin and of sucrose. To a nonsignificant extent, it affects the fluxes of erythritol and propionamide and significantly reduces the 3HHO diffusion. A size increment of the diffusion path utilized by the larger molecules is proposed. 相似文献
86.
87.
Boldogh I Hajas G Aguilera-Aguirre L Hegde ML Radak Z Bacsi A Sur S Hazra TK Mitra S 《The Journal of biological chemistry》2012,287(25):20769-20773
8-Oxo-7,8-dihydroguanine (8-oxoG), arguably the most abundant base lesion induced in mammalian genomes by reactive oxygen species, is repaired via the base excision repair pathway that is initiated with the excision of 8-oxoG by OGG1. Here we show that OGG1 binds the 8-oxoG base with high affinity and that the complex then interacts with canonical Ras family GTPases to catalyze replacement of GDP with GTP, thus serving as a guanine nuclear exchange factor. OGG1-mediated activation of Ras leads to phosphorylation of the mitogen-activated kinases MEK1,2/ERK1,2 and increasing downstream gene expression. These studies document for the first time that in addition to its role in repairing oxidized purines, OGG1 has an independent guanine nuclear exchange factor activity when bound to 8-oxoG. 相似文献
88.
González R Toledo J Cruz-Lopez L Virgen A Santiesteban A Malo EA 《Journal of economic entomology》2006,99(6):1994-2001
The behavioral and electrophysiological responses of nonirradiated male and female Anastrepha ludens (Loew) (Diptera: Tephritidae), to white sapote, Casimiroa edulis Oerst. (Rutaceae), volatiles were investigated. Females flew upwind and landed more often on fruit than on artificial fruit in wind tunnel bioassays. Males flew upwind (but not landed) more frequently on fruit than on artificial fruit. Porapak Q volatile extracts of white sapote also elicited upwind flight and landing on artificial fruit for both sexes. Gas chromatography-electroantennographic detection analysis of white sapote extracts revealed that antennae of both sexes responded to eight compounds. Two peaks were unidentified because they did not separate from the solvent. Subsequent peaks were identified by gas chromatography-mass spectrometry as styrene, myrcene, 1,2,4-trimethylbenzene, 1,8-cineole, and linalool in a proportion of 50: 21: 0.5: 27: 1.5, respectively. Eight peaks were tentatively identified as beta-trans-ocimene. The number of A. ludens captured in multilure traps baited with the synthetic white sapote blend was higher than the flies captured by the multilure unbaited traps (control) in field cages. However, the number of flies captured by traps baited with the white sapote blend was not different from that of flies captured by traps baited with hydrolyzed protein. Using standard chemical ecology techniques, we found potential attractants from wild sapote fruit for monitoring and management of A. ludens population. 相似文献
89.
In this work, we compared the effect of K+ on vesicles derived from the longitudinal (LSR) and terminal cisternae (HSR) of rabbit white muscle. In HSR, K+ was found to inhibit both the Ca2+ accumulation and the heat released during ATP hydrolysis by the Ca2+-ATPase (SERCA1). This was not observed in LSR. Valinomycin abolished the HSR Ca2+-uptake inhibition promoted by physiological K+ concentrations, but it did not modify the thermogenic activity of the Ca2+ pump. The results with HSR are difficult to interpret, assuming that a single K+ is binding to either the ryanodine channel or to the Ca2+-ATPase. It is suggested that an increase of K+ in the assay medium alters the interactions among the various proteins found in HSR, thus modifying the properties of both the ryanodine channel and SERCA1. 相似文献
90.