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排序方式: 共有811条查询结果,搜索用时 246 毫秒
1.

目的:观察青年人群近距离用眼后眼部生理及功能性参数的变化及恢复时间。

方法:前瞻性研究。随机选取2019-12/2020-06在我院进行医学验光的患者69例138眼,根据主觉验光结果分为正视组(+0.75D≤等效球镜度≤-0.50D,18例36眼)、低度近视组(-0.75D≤等效球镜度≤-3.00D,25例50眼)和中度近视组(-3.25D≤等效球镜度≤-6.00D,26例52眼)。所有受试者近距离阅读20min后远眺放松20min,分别于近距离用眼前、近距离用眼20min后、远眺5、10、15、20min时测量受试者眼部生理性参数\〖前房深度(ACD)、眼轴长度(AL)\〗和功能性参数\〖正相对调节(PRA)、调节反应(BCC)\〗,分析各参数的达极时间和恢复时间。

结果:近距离用眼后眼轴变长,前房变浅,PRA绝对值变大,BCC无明显变化,75%(52/69)的受试者AL在近距离用眼20min后达极,87%(60/69)的受试者ACD在远眺5min时达极,96%(66/69)的受试者PRA在近距离用眼20min后达极,且以上参数均在远眺10min后逐渐恢复至初始状态。

结论:近距离用眼后眼部参数发生改变,眼轴变长,前房变浅,PRA绝对值增大,但均在远眺放松过程中逐渐回退,且均需要10min以上才能恢复至初始状态。  相似文献   

2.
AIM: To explore the photopic pupil size behavior in myopic children undergoing overnight orthokeratology (ortho-k) over 1-year period and its effects on the axial elongation. METHODS: A total of 202 Chinese myopic children were enrolled in this prospective clinical trial. Ninety-five subjects in ortho-k group and eighty-eight subjects in spectacle group completed the 1-year study. Axial length (AL) was measured before enrollment and every 6mo after the start of ortho-k. The photopic pupil diameter (PPD) was determined using the Pentacam AXL and measured in an examination room with lighting of 300-310 Lx. Stepwise multiple linear regression analysis was used to identify variables contribution to axial elongation. RESULTS: Compared with spectacle group, the average 1-year axial elongation was significantly slower in the ortho-k group (0.25±0.27 vs 0.44±0.23 mm, P<0.0001). In ortho-k group, PPDs significantly decreased from 4.21±0.62 mm to 3.94±0.53 mm after 1mo of lens wear (P=0.001, Bonferroni correction) and the change lasts for 3-month visit. No significantly change during the other follow-up visits was found (P>0.05, Bonferroni correction). The 4.81 mm PPD may be a possible cutoff point in the ortho-k group. Subjects with PPD below or equal to 4.81 mm tended to have smaller axial elongation compared to subjects with PPD above 4.81 mm after 1-year period (t=-3.09, P=0.003). In ortho-k group, univariate analyses indicated that those with older age, greater degree of myopia, longer AL, smaller baseline PPD (PPDbaseline) experienced a smaller change in AL. In multivariate analyses, older age, greater AL and smaller PPDbaseline were associated with smaller increases in AL. In spectacle group, PPD tended to be stable (P>0.05, Bonferroni correction) and did not affect axial growth. CONCLUSION: PPDs experience significantly decreases at 1-month and 3-month ortho-k treatment. Children with smaller PPD tend to experience slower axial elongation and may benefit more from ortho-k.  相似文献   
3.
《Clinical neurophysiology》2020,131(11):2641-2650
ObjectiveTo assess excitability differences between motor and sensory axons of affected nerves in patients with multifocal motor neuropathy (MMN).MethodsWe performed motor and sensory excitability tests in affected median nerves of 20 MMN patients and in 20 age-matched normal subjects. CMAPs were recorded from the thenar and SNAPs from the 3rd digit. Clinical tests included assessment of muscle strength, two-point discrimination and joint position.ResultsAll MMN patients had weakness of the thenar muscle and normal sensory tests. Motor excitability testing in MMN showed an increased threshold for a 50% CMAP, increased rheobase, decreased stimulus-response slope, fanning-out of threshold electrotonus, decreased resting I/V slope, shortened refractory period, and more pronounced superexcitability. Sensory excitability testing in MMN revealed decreased accommodation half-time and S2-accommodation and less pronounced subexcitability. Mathematical modeling indicated increased Barrett-Barrett conductance for motor fibers and increase in internodal fast potassium conductance for sensory fibers.ConclusionsExcitability findings in MMN suggest myelin sheath or paranodal seal involvement in motor fibers and, possibly, paranodal detachment in sensory fibers.SignificanceExcitability properties of affected nerves in MMN differ between motor and sensory nerve fibers.  相似文献   
4.
Our current understanding of emmetropisation and myopia development has evolved from decades of work in various animal models, including chicks, non-human primates, tree shrews, guinea pigs, and mice. Extensive research on optical, biochemical, and environmental mechanisms contributing to refractive error development in animal models has provided insights into eye growth in humans. Importantly, animal models have taught us that eye growth is locally controlled within the eye, and can be influenced by the visual environment. This review will focus on information gained from animal studies regarding the role of optical mechanisms in guiding eye growth, and how these investigations have inspired studies in humans. We will first discuss how researchers came to understand that emmetropisation is guided by visual feedback, and how this can be manipulated by form-deprivation and lens-induced defocus to induce refractive errors in animal models. We will then discuss various aspects of accommodation that have been implicated in refractive error development, including accommodative microfluctuations and accommodative lag. Next, the impact of higher order aberrations and peripheral defocus will be discussed. Lastly, recent evidence suggesting that the spectral and temporal properties of light influence eye growth, and how this might be leveraged to treat myopia in children, will be presented. Taken together, these findings from animal models have significantly advanced our knowledge about the optical mechanisms contributing to eye growth in humans, and will continue to contribute to the development of novel and effective treatment options for slowing myopia progression in children.  相似文献   
5.
6.
Purpose: To introduce the Finnish practice of collaboration aiming to enhance work participation, to ask supervisors about its reasons and usefulness, to study supervisors’ needs when they face work disability, and to compare the experiences of supervisors whose profiles differ.

Materials and methods: An online questionnaire based on the Finnish practice of collaboration between supervisor and occupational health services (OHS) went to supervisors in six public and private organizations. A total of 254 supervisors responded, of whom, 133 (52%) had collaborated in work disability negotiations, representing a wide variety with differing professional profiles.

Results: In their role of managing work disability, supervisors appeared to benefit from three factors: an explicit company disability management (DM) policy, supervisors’ training in DM, and collaboration with OHS. Reasons for work disability negotiations were long or repeated sick-leaves and reduced work performance. Expectations for occupational health consultations focused on finding vocational solutions and on obtaining information. Supervisors assessed the outcomes of collaboration as both vocational and medical. Supervisors with differing professional profiles prioritized slightly different aspects in collaboration.

Conclusions: Collaboration with OHS is an important option for supervisors to enhance work modifications and the work participation of employees with work disability.

  • Implications for Rehabilitation
  • Work disability negotiation between supervisor, employee, and occupational health services (OHS) is an effective method to enhance work participation.

  • Collaboration with occupational health can advance work modifications and also lead to medical procedures to improve work performance.

  • Supervisor training, companies’ explicit disability management policy, and collaboration with OHSs all advance employee’s work participation.

  • Collaboration with OHSs may serve as training for supervisors in their responsibility to support work participation.

  相似文献   
7.
8.
BackgroundAnxiety disorders are the most common childhood-onset psychiatric disorders and are extensively associated with child functional impairment. Data suggest that family accommodation plays a role in the association between anxiety severity and functional impairment in children, but more empirical evidence is needed.MethodsParticipants were 425 clinically anxious children (ages 6–17 years), and their mothers. We first examined associations between child anxiety symptom severity, family accommodation, and child functional impairment. Next, we investigated the hypothesized mediation pathway linking anxiety severity to child impairment through increased family accommodation using structural equation modeling. We tested two models: one using parent ratings of their child’s anxiety and the other using the child’s self-ratings. Finally, we estimated the effect sizes of the mediation pathway in both models.ResultsFamily accommodation was significantly correlated with all the study variables. Child functional impairment was significantly correlated with parent-rated and self-rated child anxiety severity. Both structural equation models provided excellent fit for the data and supported the theoretical model by which family accommodation significantly explains part of the association between anxiety symptoms and functional impairment. The indirect effect sizes indicate that family accommodation accounts for between a fifth and a half of the impairment associated with symptom severity.ConclusionsThe data provide important empirical evidence that family accommodation mediates the association between child anxiety and functional impairment and accounts for up to 50 % of this association. These findings contribute to the growing understanding of the critical role of family accommodation and underscore the importance of assessing accommodation when evaluating and treating anxious children.  相似文献   
9.
10.
Abstract

Background: People with psychiatric disabilities often struggle with maintaining a satisfying occupational balance. Knowledge about factors of relevance for occupational balance in this group is therefore vital for improving their support.

Aim: The aim was to describe perceptions of occupational balance among people with psychiatric disabilities living in supported housing (SH) or in own flat/house with housing support (OHS). Potential importance of housing context and socio-demographic, well-being and recovery factors for occupational balance was also explored.

Methods: Participants from SH (N?=?155) and OHS (N?=?111) responded to questionnaires about sociodemographic situation, well-being (self-rated health, life satisfaction and self-mastery), personal recovery and occupational balance (work, leisure, home chores, self-care and general balance assessed by SDO-OB).

Results: A majority in both groups reported being in balance regarding all five domains of occupational balance. The OHS group reported being more under-occupied for home chores and self-care. Self-mastery was the most important contributor in both groups in the domains of work, domestic chores and self-care. Day center attendance was vital for general occupational balance.

Conclusion: Both groups generally perceived occupational balance. Control over one’s life situation and possibilities for regularly participating in occupations outside the home environment should receive high priority in housing support.  相似文献   
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