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41.
42.
Three-dimensional (3D) printing is a rapidly evolving and promising field to improve outcomes of orthopaedic surgery. The use of patient-specific 3D-printed models is specifically interesting in paediatric orthopaedic surgery, as limb deformity corrections often require an individual 3D treatment. In this editorial, various operative applications of 3D printing in paediatric orthopaedic surgery are discussed. The technical aspects and the imaging acquisition with computed tomography and magnetic resonance imaging are outlined. Next, there is a focus on the intraoperative applications of 3D printing during paediatric orthopaedic surgical procedures. An overview of various upper and lower limb deformities in paediatrics is given, in which 3D printing is already implemented, including post-traumatic forearm corrections and proximal femoral osteotomies. The use of patient-specific instrumentation (PSI) or guiding templates during the surgical procedure shows to be promising in reducing operation time, intraoperative haemorrhage and radiation exposure. Moreover, 3D-printed models for the use of PSI or patient-specific navigation templates are promising in improving the accuracy of complex limb deformity surgery in children. Lastly, the future of 3D printing in paediatric orthopaedics extends beyond the intraoperative applications; various other medical applications include 3D casting and prosthetic limb replacement. In conclusion, 3D printing opportunities are numerous, and the fast developments are exciting, but more evidence is required to prove its superiority over conventional paediatric orthopaedic surgery.  相似文献   
43.
We explored the relationship between hand orientation and movement time. Three groups of participants (n = 8 per group) were asked to grasp an object rotated in one of the following planes: (1) coronal; (2) sagittal; (3) horizontal. In the coronal plane, the rotational requirements directly mapped onto the neuromuscular demands associated with a single joint-level degree of freedom movement. A simple lawful relationship was found between the extent of rotation (pronation or supination) and duration. Reach-to-grasp movements to objects rotated in the sagittal and horizontal plane produced different movement patterns. These patterns increased the muscle level degrees of freedom recruited (higher neuromuscular demands) and movement duration increased correspondingly though not in a simple manner. The results of the present study show unambiguously that object orientation influences the duration of reach-to-grasp movements.  相似文献   
44.
OBJECTIVE: To assess the association between physical fitness and its recovery over time on the one hand, and complications and duration of phases of rehabilitation on the other. DESIGN AND SETTING: Prospective cohort study at eight rehabilitation centres. SUBJECTS: People with a spinal cord injury were assessed four times: at the start of active rehabilitation (n = 110), three months later (n = 92), at discharge (n = 137) and a year after discharge from inpatient rehabilitation (n = 91). MAIN MEASURES: Physical fitness was defined as aerobic capacity, determined at each occasion by the peak oxygen uptake (peak Vo(2); L/min) and the peak power output (peak PO; W) during a maximal exercise test. On these occasions, spasticity, musculoskeletal and neurogenic pain were determined (1 = present; 0 = absent). During inpatient rehabilitation, complications (urinary tract infection, pulmonary infection or pressure sore) and bed rest were registered (1 = complication; 0 = no complications, and 1 = bed rest; 0 = no bed rest). Complications and bed rest occurring during the year after discharge were registered similarly. RESULTS: Multilevel random coefficient analyses revealed associations in multivariate models (P 相似文献   
45.
研究了红葡萄柚和金黄色葡萄柚的生物活性化合物含量及其对高甘油三酯血症患者的影响。结果发现,与金黄色葡萄柚相比,红葡萄柚生物活性化合物含量和抗氧化能力均较高,该发现决定于氧自由基清除能力、1,1-二苯基-2-苦味基月井(1,1-diphenyl-2-picrylhydrazyl,DPH)、类胡萝卜素漂  相似文献   
46.
The capability to adapt to changing conditions is crucial for safe and successful performance in physical activities and sports. According to the affordance-based control perspective, individuals act in such a way as to take into account the limits of their capability to act. However, it is not clear how strength interacts with skill in shaping performer-environment interactions. We, therefore, determined whether fingertip strength influences patterns of gaze and climbing behavior on new routes of ever-increasing difficulty. We expected that comparatively weaker climbers would show less complex behavior because of an inability to perceive and act. Stronger climbers would show more complex visuo-motor behavior because more opportunities for action remain, even as route difficulty increases. For very strong climbers the route would not be challenging enough, and less complex patterns suffice. Twenty climbers, ranging from lower grade to elite level participated. Maximum fingertip strength was obtained. Participants previewed and then climbed two separate 3 m long traverses, gradually decreasing in edge depth. Gaze and hip positions were collected for subsequent computation of gaze transition entropy (during preview) and hip displacement entropy (during climbing). Data revealed statistically significant curvilinear relationships between both fingertip strength and gaze transition entropy, and fingertip strength, and hip displacement entropy. Visuo-motor complexity is scaled by how close the individual must act relative to boundaries of what the environment affords and does not afford for action given the individual constraints. Future research should examine in greater detail relationships between action capabilities and functional movement variability.  相似文献   
47.

Background

Motor vehicle crashes are a leading cause of death among children in the United States. Age- and size-appropriate child restraint use is the most effective method for reducing these deaths.

Methods

CDC analyzed 2002–2011 data from the Fatality Analysis Reporting System to determine the number and rate of motor-vehicle occupant deaths, and the proportion of unrestrained child deaths among children aged <1 year, 1–3 years, 4–7 years, 8–12 years, and for all children aged 0–12 years. Age group–specific death rates and proportions of unrestrained child motor vehicle deaths for 2009–2010 were further stratified by race/ethnicity.

Results

Motor vehicle occupant death rates for children declined significantly from 2002 to 2011. However, one third (33%) of children who died in 2011 were unrestrained. Compared with white children for 2009–2010, black children had significantly higher death rates, and black and Hispanic children both had significantly higher proportions of unrestrained child deaths.

Conclusions

Motor vehicle occupant deaths among children in the United States have declined in the past decade, but more deaths could be prevented if restraints were always used.

Implications for Public Health

Effective interventions, including child passenger restraint laws (with child safety seat/booster seat coverage through at least age 8 years) and child safety seat distribution plus education programs, can increase restraint use and reduce child motor vehicle deaths.  相似文献   
48.
In the past decades, clinical and experimental evidence has demonstrated that psoriasis is an immune-mediated inflammatory disease of the skin that occurs in genetically susceptible individuals. Psoriasis also shows clear autoimmune pathomechanisms, but specific cellular targets for the onset and maintenance of psoriatic lesions were not established until 2014. Since then, four psoriasis autoantigens were discovered, namely cathelicidin LL-37, melanocytic ADAMTSL5, lipid antigen PLA2G4D and keratin 17. Autoreactive T cells against these autoantigens were found in a number of patients with moderate-to-severe plaque psoriasis. Moreover, the discovery of autoantibodies against LL-37 and ADAMTSL5 and their strong association with psoriatic arthritis (PsA) suggest a potential role of these autoantibodies in the pathogenesis of PsA. This review discusses the current studies on psoriatic autoantigens and the associated circulating autoantibodies and their mechanisms involved in the development and maintenance of psoriatic plaques. Recent autoimmune evidence fuelled the discussion on psoriasis as an autoimmune skin disorder and has the potential to develop new treatment strategies with protective and therapeutic antigen-targeted methods.  相似文献   
49.
50.

Background

In the Netherlands, screening for chlamydia (the most prevalent sexually transmitted infection worldwide) is a relatively simple and free procedure. Via an invitation letter sent by the public health services (PHS), people are asked to visit a website to request a test kit. They can then do a chlamydia test at home, send it anonymously to a laboratory, and, within two weeks, they can review their test results online and be treated by their general practitioner or the PHS. Unfortunately, the participation rates are low and the process is believed to be not (cost-) effective.

Objective

The objective of this study was to assess whether the low participation rate of screening for chlamydia at home, via an invitation letter asking to visit a website and request a test kit, could be improved by optimizing the invitation letter through systematically applied behavior change theories and evidence.

Methods

The original letter and a revised letter were randomly sent out to 13,551 citizens, 16 to 29 years old, in a Dutch municipality. Using behavior change theories, the revised letter sought to increase motivation to conduct chlamydia screening tests. The revised letter was tailored to beliefs that were found in earlier studies: risk perception, advantages and disadvantages (attitude), moral norm, social influence, and response- and self-efficacy. Revisions to the new letter also sought to avoid possible unwanted resistance caused when people feel pressured, and included prompts to trigger the desired behavior.

Results

No significant differences in test package requests were found between the two letters. There were also no differences between the original and revised letters in the rates of returned tests (11.80%, 581/4922 vs 11.07%, 549/4961) or positive test results (4.8%, 23/484 vs 4.1%, 19/460). It is evident that the new letter did not improve participation compared to the original letter.

Conclusions

It is clear that the approach of inviting the target population through a letter does not lead to higher participation rates for chlamydia screening. Other approaches have to be developed and pilot tested.  相似文献   
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