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101.
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103.
Steenbrink F de Groot JH Veeger HE Meskers CG van de Sande MA Rozing PM 《Manual therapy》2006,11(3):231-237
A mechanical deficit due to a massive rotator cuff tear is generally concurrent to a pain-induced decrease of maximum arm elevation and peak elevation torque. The purpose of this study was to measure shoulder muscle coordination in patients with massive cuff tears, including the effect of subacromial pain suppression. Ten patients, with MRI-proven cuff tears, performed an isometric force task in which they were asked to exert a force in 24 equidistant intervals in a plane perpendicular to the humerus. By means of bi-polar surface electromyography (EMG) the direction of the maximal muscle activation or principal action of six muscles, as well as the external force, were identified prior to, and after subacromial pain suppression. Subacromial lidocaine injection led to a significant reduction of pain and a significant increase in exerted arm force. Prior to the pain suppression, we observed an activation pattern of the arm adductors (pectoralis major pars clavicularis and/or latissimus dorsi and/or teres major) during abduction force delivery in eight patients. In these eight patients, adductor activation was different from the normal adductor activation pattern. Five out of these eight restored this aberrant activity (partly) in one or more adductor muscles after subacromial lidocaine injection. Absence of glenoid directed forces of the supraspinate muscle and compensation for the lost supraspinate abduction torque by the deltoideus leads to destabilizating forces in the glenohumeral joint, with subsequent upward translation of the humeral head and pain. In order to reduce the superior translation force, arm adductors will be co-activated at the cost of arm force and abduction torque. Pain seems to be the key factor in this (avoidance) mechanism, explaining the observed limitations in arm force and limitations in maximum arm elevation in patients suffering subacromial pathologies. Masking this pain may further deteriorate the subacromial tissues as a result of proximal migration of the humeral head and subsequent impingement of subacromial tissues. 相似文献
104.
Marital status, quality of life, and clinical outcome in patients with heart failure 总被引:2,自引:0,他引:2
Luttik ML Jaarsma T Veeger N van Veldhuisen DJ 《Heart & lung : the journal of critical care》2006,35(1):3-8
AIM: This study investigated the impact of having a partner on quality of life (QoL), the number of hospital readmissions, and 9-month survival in patients with heart failure (HF). METHODS: The study population consisted of hospitalized patients with HF. QoL was measured by the Cantril Ladder of Life (0-10) during hospital admission. Clinical data, readmission rate, and number of deaths were registered by patient interview and chart review. RESULTS: Of the 179 patients, 96 (54%) were married or were living with a partner. Differences in QoL between married patients and those living alone were most pronounced with regard to future expectations of QoL (6.5 vs 5.0, P=.00). However, in a multivariate model QoL was primarily associated with socioeconomic status, age, and gender. Married patients had 12% less events in the 9-month follow-up period compared with patients living alone (P=not significant). CONCLUSION: This study indicates that most patients with HF who are living alone are mostly elderly women with a low socioeconomic status, who are at risk for recurrent events and a worse QoL. 相似文献
105.
Charlotte L. Denholt Bertrand Kuhnast Frédéric Dollé Francoise Hinnen Paul R. Hansen Nic Gillings Andreas Kjær 《Journal of labelled compounds & radiopharmaceuticals》2010,53(13):774-778
There is growing interest in the use of radiolabelled peptides as receptor targeting agents for diagnostic imaging of various cancer types using positron emission tomography. In this work, 1‐[3‐(2‐[18F]fluoropyridin‐3‐yloxy)propyl]pyrrole‐2,5‐dione ([18F]FPyME) has been used for parallel fluorine‐18 labelling of PEPHC1, a peptide selective towards the cancer‐specific mutation of the epidermal growth factor receptor (EGFRvIII), and a number of truncated and mutated analogues. Conjugation of the peptides with [18F]FPyME was achieved within 10 min in non‐decay‐corrected radiochemical yields of 30–50%. The high yield of the conjugation reaction combined with its short synthesis time allows the labelling of several peptides from a single batch of [18F]FPyME. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
106.
107.
Arnet U van Drongelen S van der Woude LH Veeger DH 《Clinical biomechanics (Bristol, Avon)》2012,27(1):1-6
Background
The manual wheelchair user population experiences a high prevalence of upper-limb injuries, which are related to a high load on the shoulder joint during activities of daily living, such as handrim wheelchair propulsion. An alternative mode of propulsion is handcycling, where lower external forces are suggested to be applied to reach the same power output as in handrim wheelchair propulsion. This study aimed to quantify glenohumeral contact forces and muscle forces during handcycling and compare them to previous results of handrim wheelchair propulsion.Methods
Ten able-bodied men propelled the handbike on a treadmill at two inclines (1% and 4% with a velocity of 1.66 m/s) and two speed conditions (1.39 and 1.94 m/s with fixed power output). Three-dimensional kinematics and kinetics were obtained and used as input for a musculoskeletal model of the arm and shoulder. Output variables were glenohumeral contact forces and forces of important shoulder muscles.Findings
The highest mean and peak glenohumeral contact forces occurred at 4% incline (420 N, 890 N respectively). The scapular part of the deltoideus, the triceps and the trapezius produced the highest force.Interpretation
Due to the circular movement and the continuous force application during handcycling, the glenohumeral contact forces, as well as the muscle forces were clearly lower compared to the results in the existing literature on wheelchair propulsion. These findings prove the assumption that handcycling is mechanically less straining than handrim wheelchair propulsion, which may help preventing overuse to the shoulder complex. 相似文献108.
Attention to tracer dose principles is crucial in positron emission tomography (PET), and deviations can induce serious errors. In this study, we devise a method for determining receptor occupancy of the mass dose of the radioligand itself and the in vivo affinity.
Methods
The approach was used for [11C]SB207145, a new PET radioligand for imaging the cerebral 5-HT4 receptors in humans. Test–retest PET studies with varying specific activities of [11C]SB207145 were conducted in seven healthy subjects, and the output parameter regional BPND was modeled. Individual occupancy plots were first computed to estimate the mass dose that saturates 50% of receptors (ID50), and subsequently, the maximal mass dose that can be injected (arbitrarily set at an occupancy <5%) was calculated. Scatchard plots were computed to estimate the in vivo KD.Results
Increasing the mass dose resulted in a decrease in BPND, whilst the relative cerebellar uptake was unchanged. The ID50 was 85.4±30.2 μg, and the upper mass dose limit was 4.5±1.6 μg, which does not require ultrahigh specific activity. The estimated in vivo KD was 2.8 nM (range 1.0–4.8), without any regional differences.Conclusion
The presented method for estimating the upper mass dose limit is suggested as part of validation of PET radioligands. 相似文献109.
Mariane Sentenac Aoife Gavin Catherine Arnaud Michal Molcho Emmanuelle Godeau Saoirse Nic Gabhainn 《The Journal of adolescent health》2011,48(5):461-466
PurposeTo explore bullying victimization among French and Irish students with a disability or chronic illness (D/CI), considering individual, social, and family factors. We investigated this issue in France and Ireland because of the documented differences between these two countries on relevant contextual factors.MethodsData from 12,048 students aged 11, 13, and 15 years (50.1% were boys) as part of the cross-national study 2006 Health Behaviour in School-aged Children were analyzed. Self-completion questionnaires were administered in classrooms; information on socio-demographic characteristics, bullying involvement, D/CI, school participation, social network, and family were collected. Multivariate logistic regressions were performed with individual, social, and family cofactors.ResultsOverall, the prevalence of bullying victimization was significantly higher in France compared with Ireland (34.2% [33.1–35.5] and 25.9% [24.5–27.4, respectively]). Youngest were more likely to report victimization; however, no gender differences were observed. In both countries, students with D/CI were significantly more likely to report that they have been bullied compared with students without D/CI, and a significant additional risk of being bullied was found when students reported D/CI with restriction in school participation. Regardless of country and D/CI status, being bullied was significantly associated with weaker social support and difficulty of communication with fathers, with even stronger associations found among students with D/CI.ConclusionAdolescents with D/CI are more likely to be victimized than their peers, with a similar risk in both countries. Besides individual, social and family factors are consistently associated to bullying victimization across countries. These results will guide future antibullying prevention programs. 相似文献
110.
Maria Giouzeli Nic A Williams Lorne J Lonie Lynn E DeLisi Timothy J Crow 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2004,(1):1-9
Protocadherin X and Protocadherin Y (PCDHX and PCDHY) are cell-surface adhesion molecules expressed predominantly in the brain. The PCDHX/Y gene-pair was generated by an X-Y translocation approximately 3 million years ago (MYA) that gave rise to the Homo sapiens-specific region of Xq21.3 and Yp11.2 homology. Genes within this region are expected to code for sexually dimorphic human characteristics, including, for example, cerebral asymmetry a dimension of variation that has been suggested is relevant to psychosis. We examined differences in patients with schizophrenic or schizoaffective psychosis in the genomic sequence of PCDHX and PCDHY in coding and adjacent intronic sequences using denaturing high performance liquid chromatography (DHPLC). Three coding variants were detected in PCDHX and two in PCDHY. However, neither the coding variants nor the intronic polymorphisms could be related to psychosis within families. Low sequence variation suggests selective pressure against sequence change in modern humans in contrast to the structural chromosomal and sequence changes including fixed X-Y differences that occurred in this region earlier in hominid evolution. Our findings exclude sequence variation in PCDHX/Y as relevant to the aetiology of psychosis. However, we note the unusual status of this region with respect to X-inactivation. Further investigation of the epigenetic control of PCDHX/Y in relation to psychosis is warranted. 相似文献