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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
371

Self-efficacy expectations and functional ability in everyday activities in clients undergoing total knee arthroplasty

Wallace, Linda S. January 2000 (has links)
This longitudinal, descriptive study based on Bandura's self-efficacy theory (1977), examined the effects of educational activities on self-efficacy and of self-efficacy on functional ability in everyday activities in clients undergoing elective, primary, unilateral, total knee arthroplasty (TKA). Educational activities included: attending a joint replacement class and a physical therapy session, performing exercises, and reading educational materials. Other sources of client information were also discussed. Self efficacy was assessed regarding confidence in ability to perform activities required for discharge home. Cronbach's alpha for the self-efficacy scale was .94 (pre-education) and .81 (post-education). Functional ability in everyday activities was operationalized as length of hospital stay, discharge placement, and perceived health status. Perceived health status was assessed using the three-scale Western Ontario McMasters University Osteoarthritis Index (WOMAC). Cronbach's alpha was: pain .85, joint stiffness .76, and physical function .94 (preoperatively); and pain .86, joint stiffness .80, and physical function .94 (postoperatively).Evidence was collected from a convenience sample of 31 participants: (a) when the process of scheduling surgery began; (b) before surgery, after the client had opportunities to participate in educational activities, and (c) approximately six weeks after surgery. The orthopedic surgeon and professional staff reviewed instruments for validity. Five clients reviewed the questionnaires for understandability and readability. Data were analyzed using Pearson r correlation coefficients, independent samples t-tests, analyses of variance and chi-square tests. An alpha level of .05 was designated as significant.Higher self-efficacy scores were associated with more expected benefits, previous TKA, and greater pain relief. Lower self-efficacy scores correlated with greater improvement in self-efficacy. Shorter lengths of hospital stay were associated with greater joint stiffness reduction, younger age and previous TKA. Discharge home was associated with younger age and living with someone else. Participants that were "very sure" of the need for TKA exhibited higher self-efficacy scores than participants that were "unsure". Improved outcomes were not associated with any one type of educational activity.This study highlighted the need for further refinement of context sensitive self-efficacy instruments, more sophisticated means of assessing the impact of an increasing array of information sources and more longitudinal studies with larger sample sizes. / Department of Educational Leadership
372

Functional and radiological evaluation of autologous chondrocyte implantation using a type I/III collagen membrane: from single defect treatment to early osteoarthritis

Robertson, William Brett January 2007 (has links)
[Truncated abstract] Hyaline articular cartilage is a highly specialised tissue consisting of chondrocytes embedded in a matrix of proteoglycan and collagens. Hyaline articular cartilage withstands high levels of mechanical stress and continuously renews its extracellular matrix. Despite this durability, mature articular cartilage is vulnerable to injury and disease processes that cause irreparable tissue damage. Native hyaline articular cartilage has poor regenerative capacity following injury, largely due to the tissue's lack of blood and lymphatic supply, as well as the inability of native chondrocytes to migrate through the dense extracellular matrix into the defect site. Articular cartilage injuries that fail to penetrate the subchondral bone plate evoke only a short-lived metabolic and enzymatic response, which fails to provide sufficient new cells or matrix to repair even minimal damage. Clinically, it has previously been accepted that treatment of such defects does not result in the restoration of normal hyaline articular cartilage, which is able to withstand the mechanical demands that are placed on the joint during every day activities of daily living. ... Historically, rehabilitation following ACI has not kept pace with the advances in cell culture and surgical technique. Subsequently, there exists a significant gap in knowledge regarding `best practice' in post operative rehabilitation following ACI. The importance of structured rehabilitation in ACI should not be underestimated when evaluating the clinical success of this chondral treatment. Patients should not be left to their own devices following ACI surgery, as the risk of damage to their implant (via delamination) is high if immediate postoperative movement is not controlled. Furthermore, the biological longevity and clinical success of the graft is dependent on a controlled and graduated return to ambulation and physical activity, and the biomechanical stimulation of the implanted chondrocytes.
373

Examination of the association between the frequency of helmet use and other lifestyle behaviors a report submitted in partial fulfillment ... for the degree of Master of Science, Parent-Child Nursing ... /

Yee, Michelle M. January 1996 (has links)
Thesis (M.S.)--University of Michigan, 1996.
374

Remediation of sustained attention following traumatic brain injury: vigilance task training and the generalization of its effects

Van Doren, Jon Jay 03 July 2018 (has links)
Studies of sustained-attention retraining following brain injury are reviewed, and found to have produced inconclusive results. The reason for this, it is suggested, is that a standard operational analysis of attention has not been applied, as evidenced by considerable inconsistency in the dependent measures and treatment methods used from study to study. The present study addresses this concern by applying well established principles of operant conditioning to the analysis and remediation of attention deficits. After briefly reviewing the variety of task parameters in the attention literature, noting ambiguities inherent in the various conceptualizations of attention, it is decided to train vigilance task performance, a relatively unambiguous and uncontroversial operational definition of sustained attention. Both the principle of immediacy, of reinforcement (feedback of correct and incorrect on each trial) and shaping (gradual increase of speed demands contingent on increased performance accuracy) are employed. The issue of generalization is deemed central to concerns of treatment efficacy, and is explored by administration of alternate versions of the same basic vigilance task. Results show that training with immediate reinforcement and speed-shaping produced better acquisition of the trained task than delayed feedback and invariant speed of stimulus presentation. Furthermore, gains resulting from training were essentially limited to the task on which training was conducted, with little evidence for generalization to like tasks employing different stimuli. These results are discussed in terms of the applicability of the construct of sustained attention to head injury rehabilitation. / Graduate
375

Effect of repeated eccentric demands placed on the lower limb musculature during simulated Rugby Union play

Brown, Lisa Gill January 2010 (has links)
Epidemiological studies consistently report that muscular strains are a primary injury type in rugby union with the majority of the strains occurring to the quadricep and hamstring musculature. Recently it has been suggested that poor eccentric muscular strength is a precursor to hamstring and quadriceps strains during intermittent sports that require rapid acceleration and deceleration. Despite the high incidence of these muscle injuries in Rugby Union there has been little research into the possible mechanisms involved. Thus, the purpose of this study was to measure the physiological and perceptual responses during a simulated Rugby Union laboratory protocol and further, to identify changes in muscle recruitment patterns and muscle strength over time by comparing this protocol to a continuous, constant load protocol covering the same distance. The experimental condition (EXP) required university level players to perform 80 minutes of simulated rugby union play in a laboratory setting (on a walkway of 22m) which was compared to that of a control condition (CON) which involved subjects covering the same distance, at a constant speed of 4.2km.h-1 on a treadmill. Physiological, biophysical and perceptual responses were measured pre-, at half-time and post-protocol. Heart rate was significantly (p<0.01) greater as a result of EXP in comparison to the CON. Electromyography (EMG) of the vastus medialis was significantly (p<0.01) greater during the CON protocol. The EXP condition elicited higher iEMG activity in the hamstring musculature at all time intervals. In addition the iEMG of the semitendinosus decreased significantly (p<0.01) as a result of the EXP protocol. Peak eccentric knee extensors (EXT) (-13.19%) and flexors (FLEX) (-12.81%) torque decreased significantly during the experimental protocol. After passive half-time (236.67 + 56.27Nm (EXT) and 173.89 + 33.3NM (FLEX)) and at the end of the protocol (220.39 + 55.16Nm and 162.89 + 30.66Nm) reduced relative to pre protocol (253.89 + 54.54Nm and 186.83 + 33.3Nm). Peak eccentric knee extensors did not change during the control protocol. „Central‟ and ‟Local” Rating of Perceived Exertion values were significantly (P<0.01) greater during the EXP protocol with an increased incidence of hamstring discomfort and perceived pain (5 out of 10). The EXP protocol resulted in significantly (p<0.01) increased incidence of delayed onset muscle soreness (DOMS). In conclusion, a stop-start laboratory protocol elicited increased heart rate, negatively impacted on muscle activity of the hamstrings, decreased eccentric strength in the lower limb musculature, resulted in increased ratings of „Central‟ and „Local‟ exertion and increased pain perception and increased incidence of DOMS. Thus, a stop-start rugby specific laboratory protocol has a negative impact on performance. Due to the specificity of the protocol being designed to match the demands of competitive match play it is expected that these changes in heart rate, muscle activity and strength, particularly eccentric strength, will impact negativity on performance during rugby match play and increase the likelihood of injury
376

"Glory is temporary, brain injury may be forever" : a neuropsychological study on the cumulative effects of sports-related concussive brain injury amongst Grade 12 school boy athletes

Whitefield, Victoria Jane January 2007 (has links)
The study investigated the long-term neuropsychological effects of repetitive mild traumatic brain injury (MTBI) due to participation in a contact sport amongst South African final year male high school athletes (N=189). The sample was divided by sports affiliation (Contact n = 115; Non-Contact n = 74) and concussion history (2+ Concussion n = 43; 0 Concussion n = 108). Comparative subgroups were statistically equivalent for age, education and estimated IQ (P > 0.05), with the Contact sport groups having markedly higher incidences of concussion than controls (p < 0.000). Measures included the ImPACT Verbal and Visual Memory, Visuomotor Speed and Reaction Time Composites, Digit Symbol Substitution and Digit Symbol Incidental Recall (immediate and delayed), the ImPACT Symptom Scale and a Post-concussion Symptom (PCS) questionnaire. Independent t-tests on cognitive measures at pre-and post-season revealed a predominant trend of Contact and 2+ Concussion groups performing worse, although only ImPACT Reaction Time at pre-season reached significance (p = 0.014). PCS comparisons revealed an overwhelming tendency of enhanced symptoms for Contact and 2+ Concussion groups with total scores being significantly different in most instances at pre-and post-season. Fatigue and aggression were the symptoms most pervasively high for the Contact and 2+ Concussion groups. Dependent t-test analyses at pre- versus post-season, revealed significant practice effects for the Contact group, not in evidence for controls on ImPACT Visual Motor Speed and Digit Symbol Incidental Recall-Delayed. Overall the results imply the possible presence of lingering neurocognitive and symptomatic concussion sequelae amongst South African final year high school participants of a contact sport. The indications gain potency when understood against the background of (i) Brain Reserve Capacity threshold theory, and (ii) the known risk of Type II error in group MTBI research, that might result in under-emphasis of subtle effects and miscalculation of cost-benefit risks. Clinical implications, and the need for prospective case-based research to ratify the results of this predominantly cross-sectional study, are discussed.
377

The meaning of falling for elderly community-dwelling individuals

Orlando, Theresa Eileen January 1988 (has links)
Falls in the elderly Canadian population pose a serious health problem; they are the leading cause of accidental death in persons aged 65 and older. The most common serious injuries associated with falling are hip fractures; more than 19,000 Canadians sustain a hip fracture yearly as a result of a fall. A review of the literature reveals that most of the studies on falling have been conducted in institutional settings. Community-based studies have identified the risk factors associated with falling to assist in case-finding and fall prevention. However, qualitative studies of falling for elderly community-dwelling individuals are non-existent. The purpose of this study is to describe the meaning of falling for elderly community-dwelling individuals. The phenomenological approach to qualitative methodology was used for this study. This approach seeks to describe human experience as it is lived. Individuals 65 years of age or older were contacted through a Long Term Care Unit. Eight women became informants, participating in repeated interviews guided by open-ended questions. From the content analysis of the data, three major categories of data that were common to the participants were identified and developed. The three categories represent levels of perception in relation to falling, which together represent the entire meaning of falling. At the first level, participants interpreted the various aspects of their falls. The second level describes the reactions to falling. The third level describes how participants coped with falling in the context of coping with aging. These findings revealed that falling was viewed as a symbol of aging and therefore, the emotional reaction to falling occurred in the context of growing old. Furthermore, it was found that coping with falling occurred in the broader context of coping with aging. The implications for nursing practise, education, and research were identified in light of the research findings. / Applied Science, Faculty of / Nursing, School of / Graduate
378

Evaluation of the Quick Inventory of Depressive Symptomatology - Self-Report (QIDS-SR) in a spinal cord injury population.

Reed, Kristin 08 1900 (has links)
Spinal cord injury (SCI) is an acute and devastating event that results in significant and permanent life changes for the individuals who are injured, as well as their families and friends. Depression has received more attention from clinicians and researchers than any other psychological issue among persons with SCI. Measurement of depression in this population has a variety of methodological issues, including inconsistent assessments used (self-report versus clinical interviews), varying definitions of depression, inclusion and exclusion of physical symptoms in the assessment process, and use of measures that do not represent DSM-IV criteria for major depressive disorder. The primary goal of this study was to evaluate the Quick Inventory of Depressive Symptomatology - Self-Report (QIDS-SR) and provide descriptive analyses of this measure with persons with SCI. Results showed that somatic symptoms were more frequently endorsed than psychological symptoms in this population. Additionally, scores on the QIDS-SR were significantly associated with a depression diagnosis in the patient's medical chart. However, QIDS-SR scores were not found to be correlated inversely with quality of life scores as predicted. The QIDS-SR was shown to have good internal consistency and convergent validity with patients with SCI. However, it failed to demonstrate construct validity. The QIDS-SR has the potential to be a valid measure with this population and further analysis of the psychometric properties with patients with SCI is warranted.
379

Extraction and biomedical application of peripheral blood stem cells in sheep and horses

Strydom, Aliki Veruschka 12 1900 (has links)
Thesis (PhD (Physiological Sciences))--University of Stellenbosch, 2007. / SUPERFICIAL digital flexor tendon injury has a serious negative impact on the competitive horse industry. Injured horses require up to a year of rest for recovery and likelihood of re-injury upon return to normal activity is as high as 80 %. Tendon healing requires (a) production of collagen by fibroblasts, to provide tensile strength and elasticity to the tendon, (b) minimisation of restrictive fibrosis, which compromises tendon gliding function and (c) minimisation of peritendinous adhesions. We review conventional treatments for tendon healing before exploring stem cell application as a therapeutic alternative. We promote the use of hematopoietic and mesenchymal stem cells derived from adult peripheral blood - as opposed to bone marrow-derived stem cells or embryonic stem cell sources - and review published research output in this regard. In conclusion, we outline our research objectives and present and discuss our results in the chapters that follow. Mononuclear cells - consisting of hematopoietic stem cells, mesenchymal stem cells and leucocytes – were isolated from the peripheral blood of sheep and horses through red blood cell lysis and blood plasma extraction. Cell counts and propidium iodide dye exclusion viability tests were conducted on the cell pellets. Sheep sub samples were tested for CD45 expression and horse sub samples for CD4 and CD11a/18 cell surface markers by flow cytometry for characterisation purposes. In both cases, separate sub samples were incubated with matched immunoglobulin (IgG) isotypes, conjugated to fluorescein isothiocyanate (FITC), to serve as controls. For the culture of mononuclear cells, 4.5 x 106 cells were selected for autologous sheep injections, 3 x 106 CD45- cells for allogeneic sheep injections (the latter excluding leucocytes that may induce an immune response) and 72 x 106 cells for horse injections. These cells were incubated with bromo-deoxyuridine (BrdU), cultured and subsets were extracted for a second round of cell counts and viability tests before being resuspended in blood plasma. For the horse samples an additional 1 x 106 mononuclear cells were incubated until reaching 60 % confluence and tested for myogenic differentiation. Low cell mortality and lack of fluorescence from IgG-FITC controls reflected effective protocols and a lack of false positive results. The fact that the equine cell population differentiated into myotubes verified the presence of mesenchymal stem cells in injections. We tested whether surgical incisions or collagenase injections best mimicked naturally occurring tendon injuries and compiled macroscopic and microscopic descriptions of tendon injury sites at seven weeks post-injury. The superficial digital flexor tendons of 27 sheep received an incision, a collagenase injection or a saline control injection. After one week a number of sheep were sacrificed while the remainder received further saline treatment and were sacrificed after another seven weeks. Tendons were examined through clinical observations, image analysis of maximum tendon diameter, mechanical testing and histological sectioning of affected tissues. Collagenase-induced injury resembled tendonitis more closely than surgically-induced injury. Collagenase-injured tendons (a) induced lengthier lameness in affected limbs, (b) were more swollen and difficult to palpate, (c) assumed the bow appearance characteristic of natural injury, (d) experienced extensive haemorrhage due to collagen lysis, (e) had decreased elasticity and capacity to carry loads and stress, (f) displayed decreased stiffness due to collagen fibre disruption and (g) developed severe inflammation. After seven weeks injured tendons displayed increased vascularisation in the areas of haemorrhage and in the adjacent collagen matrix. High inflammation rates and low collagen levels however still persisted. Collagenase injections were used to induce tendonitis in the superficial digital flexor tendons of 27 sheep. After one week these tendons received treatment with a control saline solution, autologous peripheral blood mononuclear cells (MNCs) or allogeneic peripheral blood CD45- MNCs. Healing rates were compared after a further seven week period by conducting ultrasonographic evaluations, clinical observations, image analyses of maximum tendon diameter, mechanical tests and histological investigations. Tendons treated with MNCs displayed an improvement in echogenicity and fibre linearity, higher and more organised collagen levels, stronger mechanical properties and less swelling. Although these improvements were not always significant, they provided strong evidence to suggest marked healing benefits over a longer time period. Collagenase injections were used to induce tendonitis in the superficial digital flexor tendons of four horses. After one week these tendons received treatment with either a control saline solution or autologous peripheral blood mononuclear cells (MNCs). Healing rates were compared after a further seven week period by conducting ultrasonographic evaluations, clinical observations, image analysis of maximum tendon diameter and histological investigations. Tendons treated with MNCs displayed significant improvements in fibre linearity in the direct vicinity of the lesion, as well as recovery rate thereof, and experienced less swelling when compared with their untreated counterparts. Healing trends suggested that, given a longer period of observation post-injury, more significant improvements may become apparent. Human adipose tissue is known be an easily accessible and high yielding source of multipotent mesenchymal stem cells. These stem cells could potentially be used for therapeutic advancement of tendon regeneration. Our first goal was to examine the in vitro myogenic differentiation potential of adipose-derived, adherent mononuclear cells (MNCs) from six adult sheep. The second goal was to characterise the population of cells isolated through various available ovine specific, non-mesenchymal stem cell surface markers, namely, CD1, CD31, CD34 and CD45. After incubation, only four of the six MNC cultures started to proliferate. These four cultures all exhibited high myogenic differentiation ability. The isolated cell populations did not express any of the non-mesenchymal stem cell specific cell surface markers. In conclusion, our data suggests that peripheral blood stem cells and adipose-derived stem cells are important candidate cell types for therapeutic application to improve tendon repair in horses and sheep. Sufficient time must be allowed following injury and prior to stem cell treatment (at least one month) and a controlled exercise program should be followed posttreatment. A larger sample size is required and at least six months of recovery before macroscopic and histological repair can be analysed more accurately and conclusively. Ultrasonography should be carried out on a continuous basis, as it is a non-invasive method of monitoring change over time.
380

Road to recovery: adjustment and services needed for those suffering from spinal cord injury

Chan, Wing-han, Esther., 陳詠嫻. January 1998 (has links)
published_or_final_version / Social Work / Master / Master of Social Work

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