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Introduction: Congenital amusia is a developmental disorder associated with deficits in pitch height discrimination or in integrating pitch sequences into melodies. This quasi-experimental pilot study investigated whether there is an association between pitch and numerical processing deficits in congenital amusia. Since pitch height discrimination is considered a form of magnitude processing, we investigated whether individuals with amusia present an impairment in numerical magnitude processing, which would reflect damage to a generalized magnitude system. Alternatively, we investigated whether the numerical processing deficit would reflect a disconnection between nonsymbolic and symbolic number representations. Method: This study was conducted with 11 adult individuals with congenital amusia and a control comparison group of 6 typically developing individuals. Participants performed nonsymbolic and symbolic magnitude comparisons and number line tasks. Results were available from previous testing using the Montreal Battery of Evaluation of Amusia (MBEA) and a pitch change detection task (PCD). Results: Compared to the controls, individuals with amusia exhibited no significant differences in their performance on both the number line and the nonsymbolic magnitude tasks. Nevertheless, they showed significantly worse performance on the symbolic magnitude task. Moreover, individuals with congenital amusia, who presented worse performance in the Meter subtest, also presented less precise nonsymbolic numerical representation. Conclusions: The relationship between meter and nonsymbolic numerical discrimination could indicate a general ratio processing deficit. The finding of preserved nonsymbolic numerical magnitude discrimination and mental number line representations, with impaired symbolic number processing, in individuals with congenital amusia indicates that (a) pitch height and numerical magnitude processing may not share common neural representations, and (b) in addition to pitch processing, individuals with amusia may present a deficit in accessing nonsymbolic numerical representations from symbolic representations. The symbolic access deficit could reflect a widespread impairment in the establishment of cortico-cortical connections between association areas.  相似文献   
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Background:The eye is an important sensory organ occupationally exposed to ionizing radiation (IR) in healthcare workers (HCWs) engaged in medical imaging (MI). New evidence highlights the possible induction of cataract at IR exposure levels to be much lower than expected in the past.Objective:Conduct an updated review on the current evidence on cataract risk in healthcare workers exposed to IR.Methods:Published scientific studies on cataract risk in IR exposed healthcare workers were collected through a systematic search of two biomedical databases (MEDLINE and Scopus). Data from included studies was extracted and summarized. Study quality was also assessed.Results:All 21 eligible studies reported an increased prevalence of cataract, especially posterior subcapsular cataract, in IR exposed HCWs with a higher prevalence in interventional cardiology staff.Discussion:Our review synthesizes the latest evidence to support the hypothesis of a significantly increased risk of occupational cataract in healthcare workers operating MI and exposed to IR, especially in interventional cardiologists. Data also support a dose-response relationship between IR exposure and the prevalence of opacities, especially posterior subcapsular opacities.Conclusions:Findings highlight the need for effective control measures including appropriate training, adherence to protective procedures, and a constant use of shields and eye personal protective equipment in healthcare workers with optical exposure to IR. Periodic health surveillance programs, possibly including lens evaluation, are also important to monitor cataract risk in these MI operators.Key words: Healthcare workers, ionizing radiation, cataract, radiation, radiology, radiologist work-related injury, occupational injury, occupational exposure, interventional radiology, radiation protection, radiation-induced cataract, interventional fluoroscopy, dosimetry, radiation workers, dosimeter, radiation effects  相似文献   
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The increase of obesity, bad eating habits and the lack of physical exercises are highly related to dyslipidemias. Rosuvastatin is a lipid‐lowering drug and has been indicated to prevent cardiovascular diseases and to treat dyslipidemias due to its higher efficiency to reduce serum cholesterol concentrations. This study aimed to evaluate the reproductive adverse effects on sexual maturity due to rosuvastatin exposure in juvenile male rats during prepuberty. Three groups were randomly formed with newly weaned rats: control, whose rats received saline solution 0.9% and rosuvastatin at doses of 3 or 10 mg kg–1 day–1, administered orally by gavage, from postnatal day 21 until preputial separation (average of 45 days for controls and 49 days for statin‐treated animals), indicative of puberty onset. Male rats were maintained until sexual maturity and were killed on postnatal day 110. In the rosuvastatin‐treated groups, the results showed diminished follicle‐stimulating hormone, luteinizing hormone and testosterone concentrations, increased estradiol and prolactin concentrations, histopathologic alterations on testis and epididymis and decreased sperm quality. Moreover, statin‐exposed groups showed decreased expression of androgen receptor on testis and epididymis and lower expression of aquaporin‐9 on epididymal epithelium. In conclusion, administration of rosuvastatin to prepubertal male rats provoked long‐term hormonal deregulation and impaired reproduction at adulthood.  相似文献   
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Supernumerary teeth are an infrequent developmental anomaly that can appear in any area of the dental arch and can affect any dental organ. Multiple supernumerary teeth, or hyperdontia, is rare in people with no other associated diseases or syndromes. Conditions commonly associated with hyperdontia include cleft lip and palate, trichorhinophalangeal syndrome, cleidocranial dysplasia, and Gardner's syndrome. A black girl, aged 11 years 8 months, came for consultation; radiographs showed 81 teeth: 18 deciduous, 32 permanent, and 31 supernumerary. The main concern initially was to determine whether she was syndromic, and she was referred to a geneticist. G banding analysis showed pericentric inversion of chromosome 9; the chromosome formula was 46, XX, inv (9) (p13q21). Orthodontic treatment for this patient will be a clinical challenge because of the great number of teeth to be extracted and the alterations in the shapes of the teeth. Treatment goals should be established by a multidisciplinary team, where oral surgeon, orthodontist, periodontist, and prosthodontist come together to solve a medical and dental puzzle, eliminating the pieces that do not fit and searching for new ones to obtain an occlusion that will give the patient physiologic conditions of normality and esthetic satisfaction.  相似文献   
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The electrochemical reduction mechanism of 1-(2-ammoniumethyl)-2-methyl-5-nitroimidazole bromide (2) in DMSO + 0.1 mol l?1 TBAP has been investigated by cyclic voltammetry and macroscale electrolysis, on a glassy carbon electrode, in comparison with metronidazole (1). The cyclic voltammogram of 2 is represented by three reduction waves, one of them at less negative potential, when compared to the first wave of metronidazole which indicates that it undergoes easier reduction. There is evidence for a self-protonation mechanism in the electroreduction of 2, represented by the absence of the first wave in the successive cyclic voltammogram, by the disappearance of the first reduction wave upon addition of base and increase of the same wave in the presence of exogenous proton donors. The stoichiometry of the reaction, at the first reduction wave, involves 0.8 mol electron mol?1 and yields 0.2 mol of 4e?/4H+ reduced derivative (probably an unstable hydroxylamine) and 0.8 mol of the amine derivative, the conjugated base of 2. The second and third waves are typical for nitroaromatic reduction and are related to the reduction of the nitro group in this aminoderivative.  相似文献   
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