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排序方式: 共有1464条查询结果,搜索用时 31 毫秒
41.
Corrias A Grugni G Crinò A Di Candia S Chiabotto P Cogliardi A Chiumello G De Medici C Spera S Gargantini L Iughetti L Luce A Mariani B Ragusa L Salvatoni A Andrulli S Mussa A Beccaria L;Study Group for Genetic Obesity of Italian Society of Pediatric Endocrinology Diabetology 《Clinical endocrinology》2012,76(6):843-850
Objective A recent study evidenced by metyrapone test a central adrenal insufficiency (CAI) in 60% of Prader–Willi syndrome (PWS) children. These results were not confirmed in investigations with low [Low‐Dose Tetracosactrin Stimulation Test (LDTST), 1 μg] or standard‐dose tetracosactrin stimulation tests. We extended the research by LDTST in paediatric patients with PWS. Design Cross‐sectional evaluation of adrenal stress response to LDTST in a PWS cohort of a tertiary care referral centre. Patients Eighty‐four children with PWS. Measurements Assessment of adrenal response by morning cortisol and ACTH dosage, and 1‐μg tetracosactrin test. Response was considered appropriate when cortisol reached 500 nm ; below this threshold, patients were submitted to a second test. Responses were correlated with the patients’ clinical and molecular characteristics to assess genotype–phenotype correlation. Results Pathological cortisol peak responses to the LDTST were registered in 12 patients (14·3%) who had reduced basal (169·4 ± 83·3 nm ) and stimulated (428·1 ± 69·6 nm ) cortisol levels compared to patients with normal responses (367·1 ± 170·6 and 775·9 ± 191·3 nm , P < 0·001). Body mass index standard deviation score was negatively correlated with basal and peak cortisol levels (both P < 0·001), and the patients’ ages (P < 0·001). In patients with deletion on chromosome 15, the cortisol peak was significantly lower than that in uniparental disomy (UPD) cases (P = 0·030). At multiple regression analysis, the predictors of peak response were basal cortisol, age, and UPD subclass (r2 = 0·353, P < 0·001). Standard‐dose (250 μg) tetracosactrin test confirmed CAI in 4/12 patients (4·8% of the cohort). Conclusions Our results support the hypothesis that, albeit rare, CAI may be part of the PWS in childhood. 相似文献
42.
During a screening program for the identification of β-thalassemia (β-thal) carriers in Sardinia, Italy, we identified two subjects with increased hemoglobin (Hb) levels and an abnormal Hb variant. The same variant was detected in a family member. DNA sequencing revealed a TGT > TGG mutation at codon 93 of the β-globin gene. Structural analysis demonstrated that the cystine residue at position 93 of the β chain was substituted by tryptophan. Since this amino acid substitution had not yet been reported, we designated this variant Hb Santa Giusta Sardegna for the place of birth of the subjects. This amino acid substitution occurs at the tyrosine pocket of the β chain as well as at the α1β2/α2β1 contact of the quaternary structure of the molecule. The presence of this Hb in the hemolysate causes an increased oxygen affinity, a slightly reduced Bohr effect and a reduced heme-heme interaction (n(50), Hill's constant) in comparison with those of Hb A. 相似文献
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Nerattini Matilde Rubino Federica Arnone Annachiara Polito Cristina Mazzeo Salvatore Lombardi Gemma Puccini Giulia Nacmias Benedetta De Cristofaro Maria Teresa Sorbi Sandro Pupi Alberto Sciagr Roberto Bessi Valentina Berti Valentina 《Neurological sciences》2022,43(4):2469-2480
Neurological Sciences - Alzheimer’s disease (AD) diagnosis can be hindered by amyloid biomarkers discordances. We aim to interpret discordances between amyloid positron emission tomography... 相似文献
47.
Benedetta Miglino MD Rossana Tiberio MD Stefano Astolfi MD Francesca Graziola MD Paolo Boggio MD Monica Leutner MD Guido Valente MD Roberto Franchini MD Enrico Colombo MD 《The breast journal》2016,22(3):339-341
Basal cell carcinoma (BCC) is a common skin cancer worldwide. However, BCC of the nipple and areola complex is rare. Men are more affected than women. Most of the cases were treated with simple excision. We report a case of BCC of the right nipple–areola complex in a 75‐year‐old man, treated with Mohs surgery and simple mastectomy. 相似文献
48.
Cecchi C Fiorillo C Baglioni S Pensalfini A Bagnoli S Nacmias B Sorbi S Nosi D Relini A Liguri G 《Neurobiology of aging》2007,28(6):863-876
Much experimental evidence suggests that an imbalance in cellular redox status is a major factor in the pathogenesis of Alzheimer's disease (AD). Our previous data showed a marked increase in membrane lipoperoxidation in primary fibroblasts from familial AD (FAD) patients. In the present study, we demonstrate that when oligomeric structures of Abeta 1-40 and Abeta 1-42 are added to the culture media, they accumulate quicker near the plasma membrane, and are internalized faster and mostly in APPV717I fibroblasts than in age-matched healthy cells; this results in an earlier and sharper increase in the production of reactive oxygen species (ROS). Higher ROS production leads in turn to an increase in membrane oxidative-injury and significant impairment of cellular antioxidant capacity, giving rise to apoptotic cascade activation and finally to a necrotic outcome. In contrast, healthy fibroblasts appear more resistant to amyloid oxidative-attack, possibly as a result of their plasma membrane integrity and powerful antioxidant capacity. Our data are consistent with increasing evidence that prefibrillar aggregates, compared to mature fibrils, are likely the more toxic species of the peptides. These findings provide compelling evidence that cells bearing increased membrane lipoperoxidation are more susceptible to aggregate toxicity as a result of their reduced ability to counteract amyloid oligomeric attack. 相似文献
49.
Sara?GandiniEmail author Giovanna?Masala Domenico?Palli Benedetta?Cavicchi Calogero?Saieva Ilaria?Ermini Federica?Baldini Patrizia?Gnagnarella Saverio?CainiView authors OrcID profile 《European journal of nutrition》2018,57(7):2323-2332
Purpose
Several studies in recent years have investigated the relationship between alcohol intake and melanoma risk, with conflicting results. To help clarify this issue, we conducted a literature review and dose–response meta-analysis of studies published until June 30th, 2017, that examined the association between alcohol intake (overall and by beverage type) and melanoma risk.Methods
We used random effect models with maximum likelihood estimation to calculate summary relative risk (SRR) and 95% confidence intervals (95%CI).Results
We included 20 independent studies (encompassing 10,555 melanoma cases and over 1.6 million non-cases/controls) published during 1986–2016, of which six had a prospective cohort study design. Adjustment for phenotypic characteristics and sunlight exposure was performed in 11 and nine studies, respectively. Alcohol intake was moderately associated with melanoma risk: the SRR were 1.29 (95% CI 1.14–1.45) for those in the highest vs. lowest category of current alcohol intake, and 1.96 (95% CI 1.02–3.76, I2?=?0%) for cumulative intake. In the dose–response analysis, the increase in risk associated with a 10 g increment in daily alcohol intake was 1.07 (95% CI 1.03–1.11). Risk estimates did not differ by gender, study design and adjustment for confounders; between-studies heterogeneity was acceptable, and there was no evidence of publication bias.Conclusions
Our findings suggest that alcohol drinking may be moderately associated with increased melanoma risk, although residual confounding and bias cannot be ruled out. Further research is needed to confirm these findings, clarify the role of the different alcohol sources, and investigate the interaction with known melanoma risk factors.50.
Influence of circadian rhythm on mortality after myocardial infarction: data from a prospective cohort of emergency calls 总被引:1,自引:0,他引:1
Manfredini R Boari B Bressan S Gallerani M Salmi R Portaluppi F Mehta RH 《The American journal of emergency medicine》2004,22(7):555-559
Myocardial infarction (MI) occurs more frequently in the morning as a result of the concomitant unfavorable timing of several physiological parameters and/or biochemical conditions. However, little is known about the possible influence of this circadian pattern on prognosis. To evaluate whether the time of symptom onset could potentially influence mortality from acute MI, this prospective study considered all consecutive MIs admitted to the ED of Ferrara, Italy, after a call to the Emergency Coordinating Unit from January 1, 1998, to December 31, 2001. The total sample consisted of 442 MIs (mean age, 68.7 years; males, 72%). Eighty patients (males, 82.5%) died in the ED; the remaining 362 were admitted to the hospital. Of these, 50 (males, 60%) died during their hospital stay. Based on the timing of their symptom onset, cases were categorized both into 24 1-hour intervals and four 6-hour intervals (midnight to 5:59 am, 6:00 am to 11:59 am, noon to 5:59 pm, and 6:00 pm to 11:59 pm), and the circadian distributions of fatal versus nonfatal MIs were compared. The circadian variation of MI peaked between 6:00 am and noon (P < .001), and in this period, there was a trend toward a higher frequency of fatal cases (41.5% vs. 35.2%; chi(2) = 1.911, P = .167). To verify whether this higher frequency of fatal events in the morning hours could be related to possible higher severity of cases observed in that hours, a further separate analysis considering age, infarct site, and peak levels of MB was made. Again, no significant temporal differences among the four 6-hour intervals were found between fatal and nonfatal Mis, although a trend toward older age was observed in morning MIs. Not only the frequency, but also the mortality, of acute MI could be increased in the morning hours. This could be of practical interest for emergency doctors and could have significant implications for acute treatment, because several studies have reported a lowered efficacy of thrombolytic drugs in the morning hours. 相似文献