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1.
Stimulus over-selectivity describes a phenomenon where only a subset of the relevant stimuli present in the environment, control an individual’s behavior. The current experiment explored the degree to which over-selectivity increases in old age. The level of over-selectivity in a visual discrimination task in 60 individuals aged 60–89 years was assessed, as well as the degree to which this reflected attentional control. In addition, the intellectual functioning and cognitive flexibility of the participants were assessed. Results showed that, as age increased, three effects were revealed: levels of stimulus over-selectivity increased, IQ scores decreased, and cognitive flexibility decreased. However, over-selectivity was not related to IQ or cognitive flexibility, and appeared related most to attentional impairments. Thus, ageing is related to significant declines in effective stimulus control. These effects can have a serious impact on the physical and psychological health of old adults, as well as their quality of life, and, therefore, this area of research warrants further exploration. The results are discussed in relation to the attention-deficit and comparator theory of over-selectivity. 相似文献
2.
Brittany A. Leader MD Michael J. Rutter FRACS Sally R. Shott MD Matthew M. Smith MD 《The Laryngoscope》2020,130(8):2053-2055
A 6-month-old female presented for 2 months of noisy breathing. Flexible laryngoscopy showed limited bilateral vocal fold abduction. Computed tomography revealed a non-enhancing 3.6 × 2.3 × 3.5 cystic prevertebral mass spanning C2-T. Using an endoscopic approach, the overlying mucosa was incised, and the cyst was freed and fully excised from the surrounding mucosa with blunt microlaryngeal instruments without complication. Three months postoperatively she had no respiratory issues and was eating well. Flexible laryngoscopy revealed bilateral vocal fold mobility. We propose that endoscopic removal of a cervical esophageal duplication cyst in selected cases is an alternative to open excision. Laryngoscope, 130:2053–2055, 2020 相似文献
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Meghan Tipre Paul Vijay Kingsley Tamika Smith Mark Leader Nalini Sathiakumar 《Asian Pacific journal of tropical medicine》2018,(5)
Objective: To conduct an epidemiological and clinical review of published case reports of melioidosis from India and Bangladesh. Methods: Data from published case reports were abstracted and summarized. We further compared the clinical epidemiology of the melioidosis cases in India with case series from highly endemic areas in Northern Australia and Southeast Asia to elucidate any differences in presentations and risk factors between the regions.Results: We identified a total of 99 cases published between 1953 and June 2016, originating from India(n=85) or Bangladesh(n=14). Cases were predominantly male and ranged in age from 1 month to 90 years. Diabetes mellitus was the most common risk factor reported(58%). About 28% of the cases had history of exposure via high-risk occupations or exposure to contaminated water. The overall case fatality rate(CFR) was 26%. Factors influencing mortality included the occurrence of septic shock(CFR, 80%), environmental exposure(CFR,39%), primary presentation of pneumonia(CFR, 38%), misdiagnosed and/or mistreated cases(CFR, 33%) or the presence of a risk factor(CFR, 29%). Because of the small number of cases in Bangladesh, pattern of clinical epidemiology is limited to India. Soft tissue abscess(37%)was the most common clinical presentation reported from India followed by pneumonia(24%)and osteomyelitis/septic arthritis(18%). Neurological melioidosis(n=10, 12%) presented as pyemic lesions of the brain or meninges. A few cases of prostatic abscess(n=4) in men and parotid abscess(n=4) were also noted. The above patterns were consistent with case series from Southeast Asia and Northern Australia for the most part, in terms of risk factors associated with infection and factors influencing mortality. Differences included clinical presentation of pneumonia which was notably lower than that reported in Southeast Asia and Northern Australia; a higher proportion of neurological and parotid abscess presentation; and a lower CFR compared to that reported in case series in Southeast Asia. About 39% of the cases were misdiagnosed and/or mistreated, suggesting underreporting and under estimation of the true disease burden. Conclusions: The concentration of melioidosis cases in southern and eastern states in India and in Bangladesh, which share climatic conditions and rice farming activities with known endemic areas in Southeast Asia, suggests an endemicity of melioidosis in this region. Thus, increased awareness among healthcare personnel, particularly among clinicians and nurses practicing in rural areas, and improved surveillance through case registries is essential to guide early diagnosis and prompt treatment. 相似文献
6.
Mannion, Leader, and Healy (2013) examined the frequency of comorbid disorders in children and adolescents with autism spectrum disorder and the predictors of sleep problems. This study will extend this research by investigating the predictors of comorbidity in 89 participants. Age, gender, level of intellectual disability, presence of epilepsy, attention deficit/hyperactivity disorder (AD/HD) and an anxiety disorder were determined using a self-constructed demographic questionnaire. The Autism Spectrum Disorder-Comorbid for Children (ASD-CC) was administered to informants to assess symptoms of comorbid psychopathology. The Children's Sleep Habits Questionnaire (CSHQ) and Gastrointestinal symptom inventory were administered to assess sleep problems and gastrointestinal symptoms respectively. Sleep problems predicted gastrointestinal symptoms. Level of intellectual disability predicted gastrointestinal symptoms. Specifically, those with no intellectual disability were more likely to present with gastrointestinal symptoms. Gastrointestinal symptoms in turn predicted total comorbid psychopathology score and the individual subscales of worry/depressed, avoidant behavior, conduct behavior and tantrum behavior on the ASD-CC. Gender and ASD-CC total score predicted an individual having an anxiety disorder. Specifically, being male predicted an anxiety disorder. The ASD-CC subscales of worry/depressed and avoidant behavior predicted an anxiety disorder. The implications of these findings are discussed in the study. 相似文献
7.
The transmission of harmful pathogens during commercial air flights is an increasing health concern. A potential, yet relatively overlooked source of zoonotic infectious diseases involves collisions of birds and bats with aircraft and long distance transport of their carcasses. We report a case of aerial transportation of the remains of an African fruit bat over three continents, following a collision with an aircraft, and demonstrate the relative ease with which zoonotic pathogens, such as rabies virus or other viruses associated with bats, may cross national boundaries and continents even. Improper handling and disposal of animal remains by airport personnel, may lead to exposure of both humans and local fauna to exotic pathogens. This in turn may trigger an epidemic with potentially devastating results. 相似文献
8.
Cairns SP Leader JP Loiselle DS 《Pflügers Archiv : European journal of physiology》2011,461(4):469-479
The main aim was to investigate the effects of raised [K+]o on contraction of isolated non-fatigued skeletal muscle at 37°C and 25°C to assess the physiological significance of K+ in fatigue. Mouse soleus muscles equilibrated at 25°C had good mechanical stability when temperature was elevated to 37°C. The main findings at 37°C vis-à-vis 25°C were as follows. When [K+]o was raised from 4 to 7?mM, there was greater twitch potentiation, but no significant difference in peak tetanic force. At 10?mM [K+]o there was (1) a faster time course for the decline of peak tetanic force, (2) a greater steady-state depression of twitches and tetani, (3) an increase of peak force over 50?C200?Hz (whereas it decreased at 25°C), (4) significant tetanus restoration when stimulus pulse duration increased from 0.1 to 0.25?ms and (5) greater depolarisation of layer-2 fibres, with no repolarisation of surface fibres. These combined data strengthen the proposal that a large run-down of the K+ gradient contributes to severe fatigue at physiological temperatures via depolarisation and impaired sarcolemmal excitability. Moreover, terbutaline, a ??2-adrenergic agonist, induced a slightly greater and more rapid, but transient, restoration of peak tetanic force at 10?mM [K+]o at 37°C vis-à-vis 25°C. A right shift of the twitch force?Cstimulation strength relationship at 10?mM [K+]o was partially reversed with terbutaline to confer the protective effect. Thus, catecholamines are likely to stimulate the Na+?CK+ pump more powerfully at 37°C to restore excitability and attenuate, but not prevent, the detrimental effects of K+. 相似文献
9.
Livneh Nir Braeken Dionne Drozdinsky Genady Gafter-Gvili Anat Seelig Jaap Rozovski Uri Berger Tamar Raanani Pia Falanga Anna ten Cate Hugo Spectre Galia Leader Avi 《Journal of thrombosis and thrombolysis》2021,52(2):590-596
Journal of Thrombosis and Thrombolysis - Managing anticoagulation in hematological malignancy patients with atrial fibrillation and thrombocytopenia is a clinical challenge with limited data. We... 相似文献
10.
Tormey WP Fitzgerald RJ Thomas G Kay EW Leader MB 《International journal of clinical practice》2000,54(8):520-523
The aim was to evaluate 24 hr urine catecholamine, HMMA and HVA excretion in relation to ploidy in phaeochromocytoma. Data from five diploid and nine tetraploid tumours showed a significant reduction in urine noradrenaline (p = 0.02) and HMMA (p = 0.03) in diploid tumours but no difference in adrenaline, dopamine and HVA excretion using the Mann-Whitney U test. None of the patients showed recurrence after a mean of 5.7 years of follow up. A review of published ploidy studies in phaeochromocytoma shows that malignancy is more than six times more common in non-diploid tumours but diploidy does not equate with benignity. No biochemical marker is a reliable index of malignancy. All patients should undergo lifetime review for recurrence. 相似文献