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11.
12.
Giuseppe Ravizzola Gabriele Pinsi Marina Cesana Carmela De Rango Laura Peroni Prof. Adolfo Turano 《Current microbiology》1992,24(6):349-353
The protective effects of rufloxacin againstStaphylococcus aureus-induced infections were compared with those of ciprofloxacin in the granuloma pouch model in the rat. Two strains with different in vitro sensitivity to the drugs were studied. Rufloxacin concentrations persisted longer than ciprofloxacin in the exudate in the pouch cavity and were about eight times higher. Equal doses of rufloxacin and ciprofloxacin had similar antibacterial activities. However, rufloxacin inhibitedStaphylococcus aureus bacterial growth significantly longer than did ciprofloxacin. 相似文献
13.
Marina Pitto Anna Miglio Gunther Kirschner Alberta Leon Riccardo Ghidoni 《Neurochemical research》1991,16(11):1187-1192
Semisynthetic single-chain GM1 derivatives containing N-acetyl-sphingosine (LIGA4) or N-dichloroacetyl-sphingosine (LIGA20) were recently reported to exert strong protection against glutamate-induced neuronal death in primary cultures of cerebellar granule cells. Elucidation of the molecular mechanism underlying the evoked effect requires knowledge of the metabolic fate of such molecules in the same cultured cells. For this, LIGA4 and LIGA20 were made radioactive on the long chain base moiety and added to cerebellar granule cells in culture in parallel with GM1 ganglioside. The metabolic fate was then investigated. It was found that both these molecules were easily taken up by the cells and promptly metabolized in a fashion qualitatively similar to that of control GM1. The highest amount processed was attributed to the different aggregation properties of LIGAs in solution. Among metabolites, higher accumulation of the single-chain ceramide residues was found after LIGA administration. Interestingly, sphingomyelin was generated, regardless the added compound, suggesting a recycling of the free long chain base. 相似文献
14.
A new synaptic anomaly: irregular synaptonemal complexes 总被引:1,自引:0,他引:1
J. Navarro F. Vidal C. Templado J. Benet J. M. Pomerol S. Marina J. Egozcue 《Human genetics》1986,72(3):272-274
Summary In this paper we describe a new synaptic anomaly characterized by the presence of irregular synaptonemal complexes (SCs) in two sterile patients. 相似文献
15.
Activation of human ribosomal genes by 5-azacytidine 总被引:2,自引:0,他引:2
Cultured human fibroblasts were exposed to 5-azacytidine which inhibits methylation of newly synthesized DNA. A significant increase in the mean number of Ag-stained active nucleolus organizers has been observed in treated cells. This suggests that DNA methylation is involved in modulation of human rRNA synthesis. 相似文献
16.
High resolution studies on the pattern of induced exchanges in the human karyotype 总被引:12,自引:0,他引:12
Dr. Marina Seabright 《Chromosoma》1973,40(4):333-346
The pattern of breakage and exchange induced by X-irradiation of human lymphocytes at G1 has been analysed in PHA transformed cultures at X1 metaphase in cells treated with trypsin. All the events observed occurred in interband segments. Moreover, as far as the autosomes were concerned, these events appear to be at random in relation to trypsin interband length but give some indication of non-randomness when total chromosome length is considered. The X and Y chromosomes, on the other hand, show far fewer breaks than would be expected whichever criterion is adopted, and in particular appear to be isolated from the autosomes with respect to the occurrence of exchange events. — The analysis of specific break points in relation to trypsin banding sequences, makes it clear that conclusions regarding chromosome rearrangements based solely on conventional preparations may be misleading. 相似文献
17.
18.
Marina Cinco Elena Banfi Carmelo Stornello F. Campo H. Korver 《FEMS microbiology letters》1989,47(8-9):499-504
Abstract A strain of Leptospira interrogans was isolated from a patient suffering from leptospirosis and was typed by the Gross Agglutination Absorption test using monoclonal antibodies prepared against different serovars of the Australis serogroup. This newly isolated strain belonged to serovar bratislava . It is the first reported isolation from man, in Italy, of Leptospira bratislava , thus supporting the emerging role of this serovar in human leptospirosis. 相似文献
19.
Steven A. Narod Dilys M. Parry Jillian Parboosingh Gilbert M. Lenoir Martin Ruttledge Georges Fischer Roswell Eldridge Robert L. Martuza Marina Frontali Jonathan Haines James F. Gusella Guy A. Rouleau 《American journal of human genetics》1992,51(3):486-496
Neurofibromatosis type 2 (NF2) is an autosomal dominant syndrome characterized by the development of vestibular schwannomas and other tumors of the nervous system, including cranial and spinal meningiomas, schwannomas, and ependymomas. The presence of bilateral vestibular schwannomas is sufficient for the diagnosis. Skin manifestations are less common than in neurofibromatosis type 1 (NF1; von Recklinghausen disease). The apparent clinical distinction between NF1 and NF2 has been confirmed at the level of the gene locus by linkage studies; the gene for NF1 maps to chromosome 17, whereas the gene for NF2 has been assigned (in a single family) to chromosome 22. To increase the precision of the genetic mapping of NF2 and to determine whether additional susceptibility loci exist, we have performed linkage analysis on 12 families with NF2 by using four polymorphic markers from chromosome 22 and a marker at the NF1 locus on chromosome 17. Our results confirm the assignment of the gene for NF2 to chromosome 22 and do not support the hypothesis of genetic heterogeneity. We believe that chromosome 22 markers can now be used for presymptomatic diagnosis in selected families. The NF2 gene is tightly linked to the D22S32 locus (maximum lod score 4.12; recombination fraction 0). A CA-repeat polymorphism at the CRYB2 locus was the most informative marker in our families (lod score 5.99), but because the observed recombination fraction between NF2 and CRYB2 was 10 cM, predictions using this marker will need to be interpreted with caution. 相似文献
20.
Abstract The digestive tract and its endocytotic activity in the catenulid Stenostomum grande were studied by electron microscopy. The pharynx was typical of the simplex type. At the mouth, between the integumental epithelium and the pharyngeal epithelium proper, was a transition zone. Among the epithelial cells of this transition were monociliated sensory cells and the necks of bucco-pharyngeal secretory cells of two types. The pharyngeal epithelium proper was densely ciliated, with long ciliary rootlets and mitochondria. It was surrounded by two layers of muscles. The gastrodermis consisted of phagocytes and typical secretory Minotian cells. It was underlain by a delicate basal lamina and muscle fibers. Distinctive of the phagocytes was the presence of differentiated cilia, cup-shaped mitochondria, and vacuoles with dense inclusions. Morphological differences between pharyngeal and gastrodermal cilia suggest functional differences. Experiments using latex beads as tracers and the identification of acid phosphatase in cytoplasmic vacuoles pointed to a high level of endocytotic and digestive activity in the phagocytes. Our data demonstrate that the basic structure of the digestive tract in S. grande conforms well to that of other free-living platyhelminths, but it does have ultrastructural peculiarities. 相似文献