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排序方式: 共有697条查询结果,搜索用时 46 毫秒
1.
《Clinical neurophysiology》2021,132(2):315-322
ObjectivePrevious studies have demonstrated voluntary movement alterations as well as motor cortex excitability and plasticity changes in patients with mild cognitive impairment (MCI). To investigate the pathophysiology of movement abnormalities in MCI, we tested possible relationships between movement abnormalities and primary motor cortex alterations in patients.MethodsFourteen amnestic MCI (aMCI) patients and 16 healthy controls were studied. Cognitive assessment was performed using clinical scales. Finger tapping was recorded by a motion analysis system. Transcranial magnetic stimulation was used to test the input/output curve of motor evoked potentials, intracortical inhibition, and short-latency afferent inhibition. Primary motor cortex plasticity was probed by theta burst stimulation. We investigated correlations between movement abnormalities, clinical scores, and cortical neurophysiological parameters.ResultsMCI patients showed less rhythmic movement but no other movement abnormalities. Cortical excitability measures were normal in patients, whereas plasticity was reduced. Movement rhythm abnormalities correlated with frontal dysfunction scores.ConclusionOur study in MCI patients demonstrated abnormal voluntary movement and plasticity changes, with no correlation between the two. Altered rhythm correlated with frontal dysfunction.SignificanceOur results contribute to the understanding of pathophysiological mechanisms of motor impairment in MCI. 相似文献
2.
《Journal of pediatric surgery》2023,58(4):613-618
PurposeThe purpose of this study was to analyze the management and outcomes of primary button battery ingestions and their sequelae at a single high-volume center, and to propose a risk score to predict the likelihood of a severe outcome.MethodsThe medical record was queried for all patients under 21 years old evaluated at our institution for button battery ingestion from 2008 to 2021. A severe outcome was defined as having at least one of the following: deep/circumferential mucosal erosion, perforation, mediastinitis, vascular or airway injury/fistula, or development of esophageal stricture. From a selection of clinically relevant factors, logistic regression determined predictors of a severe outcome, which were incorporated into a risk model.Results143 patients evaluated for button battery ingestion were analyzed. 24 (17%) had a severe outcome. The independent predictors of a severe outcome in multivariate analysis were location of battery in the esophagus on imaging (96%), battery size >/ = 2 cm (95%), and presence of any symptoms on presentation (96%), with P < 0.001 in all cases. Predicted probability of a severe outcome ranged from 88% when all three risk factors were observed, to 0.3% when none were present.ConclusionWe report the presentation, management, and complication profiles of a large cohort of BB ingestions treated at a single institution. A risk score to predict severe outcomes may be used by providers initially evaluating patients with button battery ingestion in order to allocate resources and expedite transfer to a center with pediatric endoscopic and surgical capabilities.Level of evidenceLevel IV.Type of studyClinical Research Paper. 相似文献
3.
Purpose
Motor skill screening tools are essential for the early detection of developmental coordination disorder (DCD). The present study aimed to examine any cultural and rater effects on these tools. This then enabled us to judge the validity of the original cut-off values for identifying diagnosable children.Methods
A community sample survey was performed in Japan; 3852 children aged 6–9?years were recruited. Both parents and teachers evaluated the motor skills of their children using the Movement Assessment Battery for Children – Second Edition Checklist. The psychometric properties were evaluated and the scoring characteristics examined based on the type of rater and country of origin, as compared to data originally sampled in the UK.Results
High reliability and validity of the Japanese samples were confirmed. The Japanese adults evaluated their children’s motor skills more rigorously than the Europeans. Additionally, there was a large disagreement between parent and teacher rating scores; the degree of agreement varied depending on the severity of motor deficits in the child.Conclusion
The first findings from a Japanese sample suggest that the assessment of motor skills in children is significantly affected by culture and rater. These cultural characteristics and rater biases strongly suggest that new cut-off values, reflecting country and rater type, be introduced for identifying children at risk of DCD. 相似文献4.
5.
BackgroundIt is an economical strategy to design a screening method to decide which patients with amyotrophic lateral sclerosis/ motor neuron disease (ALS/MND) should enter into the stage for further comprehensive neuropsychological investigation.Methods59 patients (including 8 with frank dementia) were recruited. They underwent the extensive neuropsychological evaluation and short screening batteries, namely the Mini-Mental State Examination (MMSE), the Peking Union Medical College Hospital version of Montreal Cognitive Assessment (MoCA-P) and the Frontal Assessment Battery (FAB). Results of the extensive neuropsychological evaluation were set as the gold standard to diagnose cognitive impairment, and the effectiveness of screening tests were measured against them.ResultsBy comparing the sensitivity and specificity, we found that the combination of FAB plus both or either of the other 2 short batteries provided a satisfactorily high sensitivity, but none of these screening batteries was significantly associated with quantitative behavioral measurements among non-demented subjects, the Frontal Behavioral Inventory-ALS version (FBI-ALS).ConclusionsThe combination of the FBI-ALS, the FAB, and the MMSE or the MoCA-P or both could effectively screen comorbid dementia, cognitive and behavioral impairment in ALS but this implicates a limited specificity. And the FAB needed to be validated in large Chinese sample. 相似文献
6.
The crayfish claw opener neuromuscular junction is a biological model for studying presynaptic neuromodulation by serotonin (5HT) and synaptic vesicle recycling. It has been hypothesized that 5HT enhances release by recruiting a population of either previously nonrecycling or “reluctant” vesicles to increase the readily releasable pool. To determine if 5HT activates a distinct population of synaptic vesicles, recycling membranes were labeled with the membrane dye, FM1-43. Unloading (destaining) protocols could not resolve a population of vesicles that were only releasable in the presence of 5HT. Instead, we conclude synaptic vesicles change behavior in axon terminals independent of 5HT, becoming less likely to exocytose and unload dye over periods of >1 hr after recycling. We hypothesized this to be due to the slow conversion of a portion of recycled vesicles to a difficult to release state. The possibility that vesicles in these pools were spatially separated within the terminal was tested using photoconversion of FM1-43 and transmission electron microscopy. The location of FM1-43-labeled vesicles fixed 2 min following 3 min of 20-Hz stimulation did not reveal preferential localization of recycling vesicles specifically near release sites and the distribution of labeled vesicles was not significantly different between early (2 min) and late (180 min) time points. Terminals fixed 30 s following stimulation contained a significant proportion of vesicular structures equivalent in diameter to 2–5 regular vesicles, with multivesicular bodies and calveoli rarely seen, suggesting that endocytosis during sustained release at crayfish terminals occurs via multiple routes, most commonly through large “vesicle” intermediates. 相似文献
7.
《Neurología (Barcelona, Spain)》2020,35(5):303-310
IntroductionThe Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) is frequently used in clinical practice to evaluate cognitive function. It is quick to administer (20-30 minutes) and is not influenced by a learning effect. The RBANS includes 4 parallel versions and has a high discriminative ability.Our study provides normative data from the RBANS-E (Spanish-language version of RBANS form A) for a Spanish population aged 20 to 89 years.MethodsThe study included 609 subjects aged 20 to 89 years. Participants were evaluated at baseline with a short interview, a cognitive screening test (Mini–Mental State Examination), and a functional scale (Rapid Disability Rating Scale). The RBANS-E was then administered to all 609 participants.ResultsOur results show the influence of education on all subtest scores. Sex was observed to have no impact on any subtest.ConclusionOur study provides highly useful normative data for the cognitive evaluation of young and adult populations. 相似文献
8.
9.
David B. Matchar Kirsten Eom Pamela W. Duncan Mina Lee Rita Sim Nirmali R. Sivapragasam Christopher T. Lien Marcus Eng Hock Ong 《Archives of physical medicine and rehabilitation》2019,100(1):1-8
Objective
To perform a cost-effectiveness analysis of a multifactorial, tailored intervention to reduce falls among a heterogeneous group of high-risk elderly people.Design
Randomized control trial.Settings
Communities.Participants
Adults aged at least 65 years (N=354) seen at the emergency department (ED) for a fall or fall-related injury and discharged home.Interventions
The intervention group received a tailored program of physical therapy focused on progressive training in strength, balance, and gait for a period of 3 months. They also received screening and referrals for low vision, polypharmacy, and environmental hazards. The Short Physical Performance Battery (SPPB) test was assessed at regular intervals to allocate participants into either a home-based or group center-based program. The control group received usual care prescribed by a physician and educational materials on falls prevention.Main Outcome Measures
The incremental cost-effectiveness ratio (ICER) over the 9-month study period based on intervention costs and utility in terms of quality-adjusted life years (QALYs) calculated from EuroQol-5D scores.Results
The ICER was 120,667 Singapore dollars (S$) per QALY gained (S$362/0.003 QALYs), above benchmark values (S$70,000). However, the intervention was more effective and cost-saving among those with SPPB scores of greater than 6 at baseline, higher cognitive function, better vision and no more than 1 fall in the preceding 6 months. The intervention was also cost-effective among those with 0-1 critical comorbidities (S$22,646/QALY).Conclusion
The intervention was, overall, not cost-effective, compared to usual care. However, the program was cost-effective among healthier subgroups, and even potentially cost-saving among individuals with sufficient reserve to benefit. 相似文献10.
AGET ATRP of Methyl Methacrylate Based on Thermoregulated Phase Transfer Catalysis in Organic/Aqueous Biphasic System: Facile and Highly Efficient In Situ Catalyst/Ligand Separation and Recycling 下载免费PDF全文
Xiaowu Jiang Yuan Liu Mingqiang Ding Lifen Zhang Zhenping Cheng Xiulin Zhu 《Macromolecular chemistry and physics.》2015,216(11):1171-1179
A novel polymerization system with activators generated by electron transfer for atom transfer radical polymerization (ATRP) for sustainable catalyst/ligand separation and recycling in situ is developed based on thermoregulated phase transfer catalysis in organic/aqueous biphasic system. Herein, a typical iniferter agent 1‐cyano‐1‐methylethyldiethyldithiocarbamte is used as the initiator, and CuBr2, monomethoxy poly(ethylene glycol)‐350‐supported substituted dipicolylamine (L350), ascorbic acid, and methyl methacrylate are employed as the catalyst, thermoresponsive ligand, reducing agent, and the model monomer, respectively. The “living” nature of the system is confirmed by polymerization kinetics with recycled catalyst complex aqueous solution and chain‐extension experiments via iniferter and ATRP mechanism, respectively. In addition, the catalyst residue in polymers is less than 2 ppm and the recycling efficiency of catalyst complex in water kept more than 95% even after 5 times of recovery experiments while keeping narrow molecular weight distribution (Mw/Mn < 1.33).