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Ghiorzo P Villaggio B Sementa AR Hansson J Platz A Nicoló G Spina B Canepa M Palmer JM Hayward NK Bianchi-Scarrà G 《Human pathology》2004,35(1):25-33
Little is known about the correlation between the loss of p16 expression and tumor progression in familial melanoma; no systematic study has been conducted on p16 expression in melanocytic tumors from patients carrying germline CDKN2A mutations. We analyzed 98 early primary lesions from familial patients, previously tested for germline CDKN2A status, by quantitative immunohistochemistry using 3 p16 antibodies. We found that p16 expression was inversely correlated with tumor progression and was significantly lower in melanomas, including in situ lesions, than in nevi. Of other features analyzed, tumor thickness showed the most significant correlation with p16 levels. Lesions from mutation-negative patients displayed combined nuclear and cytoplasmic staining. However, some mutation-positive lesions (ie, G101W, 113insR, M53I, R24P, and 33ins24), including benign nevi, showed nuclear mislocalization, confirming previous studies suggesting that subcellular distribution indicates functional impairment of p16. 相似文献
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Guerrero G Reiff DF Rieff DF Agarwal G Ball RW Borst A Goodman CS Isacoff EY 《Nature neuroscience》2005,8(9):1188-1196
At the Drosophila melanogaster larval neuromuscular junction (NMJ), a motor neuron releases glutamate from 30-100 boutons onto the muscle it innervates. How transmission strength is distributed among the boutons of the NMJ is unknown. To address this, we created synapcam, a version of the Ca2+ reporter Cameleon. Synapcam localizes to the postsynaptic terminal and selectively reports Ca2+ influx through glutamate receptors (GluRs) with single-impulse and single-bouton resolution. GluR-based Ca2+ signals were uniform within a given connection (that is, a given bouton/postsynaptic terminal pair) but differed considerably among connections of an NMJ. A steep gradient of transmission strength was observed along axonal branches, from weak proximal connections to strong distal ones. Presynaptic imaging showed a matching axonal gradient, with higher Ca2+ influx and exocytosis at distal boutons. The results suggest that transmission strength is mainly determined presynaptically at the level of individual boutons, possibly by one or more factors existing in a gradient. 相似文献
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Francesco Muntoni Anna Mateddu Maria Giovanna Marrosu Miiena Cau Rita Congiu Maria Antonietta Melis Antonio Cao Carlo Cianchetti 《Clinical genetics》1992,42(1):35-38
The majority of Duchenne muscular dystrophy (DMD) female carriers show dystrophin immunostaining abnormalities, although a significant proportion of clinically non-manifesting carriers are normal following this analysis. We had the opportunity to study dystrophin immunostaining in two different muscles, the vastus lateralis and the rectus abdominis of a possible DMD carrier. While the vastus showed normal dystrophin immunostaining, pathological staining was detected in her rectus abdominis. These findings seem to indicate that dystrophin expression can vary in different muscle groups of a DMD carrier. The implications of these findings in DMD carrier detection and possible dystrophin function are discussed. 相似文献
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A total of 77 mentally retarde male inpatients residing in a psychiatric institution in northern Italy were screened for the presence of stool parasites,Entamoeba histolytica particularly. Parasitological stool examination showedEntamoeba spp. (E. histolytica and/orE. dispar) in 26 cases (33.7%). In vitro culture on Robinson's medium was positive in 16 cases (61.1%); in 11 cases we could stabilize and clone the isolates and proceed to electrophoretic assays. In all cases, patterns of pathogenic zymodemes were found (zymodeme II, 3 isolates; zymodeme XII, 4 isolates; zymodeme XIV, 4 isolates). All isolates were therefore identified asE. histolytica. 相似文献
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Susan E. Hodge A. Izzet Berkel Richard A. Gatti Elena Boder M. Anne Spence 《Tissue antigens》1980,15(3):313-317
Nine HLA-typed multiplex nuclear families segregating ataxia-telangiectasia (A-T), an autosomal recessive disorder, were studied. Linkage analysis performed by lod scores and by a previously published sib pair method revealed no evidence for linkage between A-T and HLA. An alternative method of linkage detection, previously applied to xeroderma pigmentosum (XP) and HLA, was reexamined and found to contain an error. As a consequence, neither of these "DNA repair disorders" appears to be linked to HLA. 相似文献
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Maja Di Rocco Rosanna Gatti Paolo Gandullia Arrigo Barabino Paolo Picco Carla Borrone 《American journal of medical genetics. Part A》1993,47(7):1135-1140
We report on 2 unrelated patients with Costello syndrome. The first is a 5-year-old girl with “coarse” face, nasal papillomata, redundant skin of feet and hands, hyperextensible hand and finger joints, curly hair, feeding problems due to oral motor apraxia, growth and psychomotor retardation. The second is a 3-year-old boy with “coarse” face, loose skin on hands and feet, curly hair, oral motor apraxia, severe growth and psychomotor retardation. In both patients urine sialic acid levels were found to be repeatedly high. The meaning of this biochemical abnormality is discussed. © 1993 Wiley-Liss, Inc. 相似文献
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