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Hb Taybe [α38(C3) or α39(C4) Thr→0 (α1)] is an unstable hemoglobin (Hb) variant caused by a deletion of a threonine residue at codon 39 of the α1-globin chain. Usually asymptomatic or with minimal hematological abnormalities in the heterozygous state, Hb Taybe becomes clinically evident in compound heterozygosity with α-thalassemia (α-thal) or in homozygous patients. To date, Hb Taybe has been described in Israeli-Arab and Greek individuals. We report, for the first time, a patient with chronic hemolytic anemia due to the presence of Hb Taybe in trans to the α2 initiation codon mutation ATG>ACG in an Italian child. Hb Taybe was not evident at Hb analysis with cellulose acetate electrophoresis and high performance liquid chromatography (HPLC). Globin biosynthetic studies revealed an α/β-globin ratio in the range of β-thal trait. Consequently, an investigation of the α- and β-globin genes was requested in order to avoid missing any rare globin chain variant and to offer accurate genetic counseling. 相似文献
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Antonello Fadda Antonio Di Renzo Francesco Martelli Dario Marangoni Anna Paola Batocchi Daniela Giannini Vincenzo Parisi Benedetto Falsini 《Clinical neurophysiology》2013,124(8):1652-1658
ObjectiveSustained pattern stimulation in normal subjects induces adaptive changes in pattern electroretinogram (PERG), an effect that has been interpreted as a response of glial cells and retinal ganglion cells (RGC). The aim of this study was to compare the effect in normal subjects and in multiple sclerosis patients without previous optic neuritis.MethodsPERGs were elicited by a 7.5 Hz pattern stimulus, presented continuously over 152 s. Response cycles were averaged in 20 packets of 60 events each and amplitude and phase of the 2nd harmonic response was measured. Adaptive changes are expressed as amplitude reduction over the full examination time.ResultsIn normal subjects PERG amplitude declined progressively to a plateau (dA = ?0.46 μV, SE = 0.09 μV); in patients the effect size was severely reduced (dA = ?0.20 μV, SE = 0.04 μV). No significant difference was found in mean amplitude.ConclusionsThe results show reduced RGC habituation in patients, suggesting an abnormal gain and sensitivity control in the inner retina, even in absence of clinical optic neuritis. Recent findings in astrocyte biology and indications drawn from a mathematical model point to a key role of glial cells in this process.SignificanceThe proposed methodology may have implications in the assessment of MS patients and in understanding the pathophysiology of neurological and retinal disorders. 相似文献
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Raimondo L Ferrara I Stefano AD Cella CA D'Armiento FP Ciancia G Moretto R Renzo AD Carlomagno C 《International journal of hematology》2012,95(3):320-323
Primary hepatic lymphoma is an extremely rare malignancy accounting for 0.016% of all cases of non-Hodgkin lymphomas. Approximately
1–4% of histologies described show a follicular pattern. We report a case of primary hepatic non-Hodgkin lymphoma that developed
in a middle-aged woman 3 years after radical treatment (neoadjuvant chemoradiotherapy and surgery) for a rectal adenocarcinoma.
Abdomen ultrasound showed a single nodule in the liver, which raised the issue of differential diagnosis with a metastasis
from rectal cancer. After surgical removal of the nodule, histology revealed a primary B cell, stage IE follicular non-Hodgkin
lymphoma, confined to the liver; indeed, no foci of lymphoma were found elsewhere in the body. 相似文献
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Meucci G Fasoli R Saibeni S Valpiani D Gullotta R Colombo E D'Incà R Terpin M Lombardi G;IG-IBD 《Inflammatory bowel diseases》2012,18(6):1006-1010
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Fernando Neves Hugo Glauber Campos Vale Renzo Alberto Ccahuana-Vásquez Silvia Cypriano Maria da Luz Rosário de Sousa 《Journal of applied oral science : revista FOB》2007,15(4):253-258
Objective:
To evaluate the role of socioeconomic variables and self-perceived oral health in the polarization of caries among adolescents in Santa Bárbara D''Oeste, Brazil.Material and Methods:
Cross-sectional study. Sampling was randomized and sample size was defined according to WHO criteria. Two hundred and seventy seven adolescents (15 to 18 year-old) were examined by five trained examiners that assessed DMFT index according to WHO criteria. Self-perceived oral health, access to dental services and socio-demographic variables were self-reported. Student''s t tests, chi-square tests, and multivariate logistic regression (with significant caries index (SiC) as the outcome), were performed.Results:
Mean DMFT was 5.48 (±4.22) and the proportion of "caries free" subjects was 15.5%. Mean DMFT (9.71±2.85) and mean D (1.67±2.18) of SiC positive subjects were significantly higher than mean DMFT (2.88±2.17) and mean D (0.45±0.87) of SiC negative subjects (p<0.0001). Mean D of white (0.76±1.51) was significantly smaller than mean D of non-white subjects (1.32±2.01). The only variable independently associated with the "SiC positive" outcome was "report of toothache within six months prior to the study" [OR=1.83 (95%CI 1.08 to 3.12)], p<0.001.Conclusion:
SiC was associated with "report of toothache" but not with sociodemographic variables in the studied population. 相似文献60.