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31.
Home care aides risk musculoskeletal injury because they lift and move clients; the body weight of most adults exceeds the NIOSH recommended limit for lifting. Methods to reduce manual patient lifting in institutional settings are often technically or economically infeasible in home care. Our goal was to identify suitable, safe, low-technology transfer devices for home care use. Sixteen experienced home care aides performed client transfers from wheelchair to bed (upward) and bed to wheelchair (downward) in a simulated home care environment (laboratory), using four different slide boards and by hand without a device. Aides’ hand forces were measured during client transfers; aides also evaluated usability of each board. Hand forces exerted while using slide boards were mostly lower than in manual transfer, and forces were lower in downward versus upward transfers. Aides judged a board with a sliding mechanism easier to use than boards without a sliding mechanism.

Practitioner Summary: This paper provides quantitative biomechanical measurements showing that slide boards reduced the hand forces needed by home care aides to transfer clients from bed to wheel chair and vice versa, compared to manual lifting. Using a semi-quantitative usability survey, aides identified boards with a sliding mechanism easiest to use.  相似文献   

32.
Cricket-based robots   总被引:1,自引:0,他引:1  
This article describes the development of an autonomous hybrid microrobot that uses legs for propulsion and support of the rear half of the body and a pair of wheels for support of the front half. McKibben artificial muscles actuate the legs, and compressed air is generated by an onboard power plant. Control is also onboard in the form of a PIC microcontroller, from Microchip Technology Inc., that controls the actuators through four three-way valves that are each made up of a pair of microelectromechanical system devices. Its motion resembles that of a cricket.  相似文献   
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34.
Although long-term clinical studies have shown no excessive risk of lymphoma in rheumatoid arthritis (RA) patients treated with methotrexate (MTX), an increasing number of reports of this association continue to appear. We describe two cases, review the cases in the world's literature, and summarize their important characteristics. Possible oncogenic mechanisms are discussed. Most lymphoproliferation cases presented here have features of immunosuppression-associated lymphoma. The immunosuppressed state is attributable to a combination of factors, such as RA itself and the actions of MTX. The risk factors for RA patients to develop lymphoma while on MTX include severe disease, intense immunosuppression, genetic predisposition, and an increased frequency of latent infection with prooncogenic viruses such as Epstein-Barr virus (EBV). The spontaneous remission of lymphomas in eight RA patients after MTX was stopped highlights the likely causative role of the drug in the development of these malignancies. If the clinical situation permits, a period of observation for spontaneous remission after MTX is stopped is advisable. The physicians caring for RA patients on MTX should maintain a high surveillance for signs and symptoms suggestive of lymphoma.  相似文献   
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36.
The effects of mechanical injury on the metabolism of cartilage matrix are of interest for understanding the pathogenesis of osteoarthrosis and the development of strategies for cartilage repair. The purpose of the present study was to examine the effects of injury on matrix turnover in a calf articular cartilage explant system for which the effects of mechanical loading on cell activity and the cell-mediated pathways of matrix metabolism are already well characterized. New methods of quantitative autoradiography were used in combination with established biochemical and biomechanical techniques for the analysis of cell and matrix responses to acute mechanical injury, with particular attention to the processes of localized matrix turnover in the cell-associated matrices of individual chondrocytes. Matrix deposition and turnover around cells in control explants was spatially dependent, with the highest rates of proteoglycan deposition and turnover and the lowest rates of collagen deposition (as indicated by [3H]proline autoradiography) occurring in the pericellular matrix. Injurious compression was associated with (a) an abrupt decrease in the tensile load-carrying capacity of the collagen matrix, apparently associated with mechanical failure of the tissue, (b) a considerable but subtotal decrease in cell viability, marked by the emergence of an apparently inactive cell population interspersed within catabolically active but abnormally large cells, and (c) sustained, elevated rates of proteoglycan turnover, particularly in the cell-associated matrices of apparently viable cells, which involved the increased release of aggregating species in addition to a spectrum of degradation fragments that were also in controls. These results may represent an in vitro model for the responses of chondrocytes and the cartilage extracellular matrix to mechanical injury.  相似文献   
37.
Corticosteroids are effective in bringing about a clinical remission in patients with ulcerative colitis. However, in severely relapsed cases, corticosteroids are not always effective even when a high dosage is administered. In addition, the long-term use of corticosteroids often causes serious side effects. Therefore, an alternative treatment for active ulcerative colitis is necessary in order to avoid these clinical problems. In the present pilot study, the efficacy of leukocytapheresis using a centrifugal procedure was evaluated for corticosteroid-resistant, active ulcerative colitis. Fourteen patients with corticosteroid-resistant severely active ulcerative colitis were treated by leukocytapheresis. Thirteen patients (92.9%) achieved clinical remission within 4 weeks after the apheresis, and remained in remission for 8 months on average without any additional corticosteroid therapy. In the remaining patient, in whom remission was not induced, a total colectomy was performed immediately after the fourth course of leukocytapheresis. No significant side effects were noticed throughout the therapy. Both colonoscopic and histological examinations confirmed the beneficial effect of this procedure in terms of the reduction of severe inflammation of the affected colon. We found that the expression of two adhesion molecules, L-selectin and VLA4a, on the surface of peripheral leukocytes was decreased after this new therapy.  相似文献   
38.
PURPOSE: To determine the average abdominal entrance air kerma, low-contrast sensitivity, and spatial resolution in upper gastrointestinal tract fluoroscopy in the United States. MATERIALS AND METHODS: A random sample of fluoroscopic facilities was selected to be surveyed for the Nationwide Evaluation of X-ray Trends program. Measurements were performed by using a newly developed fluoroscopic phantom. The surveys were conducted by state radiation control personnel. RESULTS: Average air kerma rates 1 cm above the tabletop, free in air, were 43 mGy/min (n = 340). The rate increased to 64 mGy/min when a 1.6-mm-thick copper filter, which simulated the use of barium contrast medium, was added to increase attenuation. The average entrance air kerma, free in air, for radiographs was 3.4 mGy, and an average of 12 radiographs were obtained per examination. Of 352 facilities surveyed, 306 (87%) were able to resolve wire mesh with 20 or more lines per inch. Of 339 facilities for which percentage contrast could be calculated, 192 (57%) had minimum percentage contrast values of 4% or more. CONCLUSION: Spatial resolution for fluoroscopy is adequate for most of the facilities surveyed, but a substantial proportion of facilities could not visualize low-contrast test objects, which strongly suggests image quality problems.  相似文献   
39.
The combination of IFN-alpha-2a (IFN-alpha) and IFN-gamma-1b (IFN-gamma) has been found to produce more than additive cytotoxicity with fluorouracil (5-FU) in HT 29 colon cancer cells due to enhanced DNA-directed effects. We therefore studied the combination of IFN-gamma with IFN-alpha, 5-FU, and leucovorin (LV) in a clinical trial. Fifty-three patients received an initial cycle of 5 million units (MU)/m2 IFN-alpha s.c. on days 1-7 with 500 mg/m2 LV and 370 mg/m2 5-FU i.v. on days 2-6. IFN-gamma was then added once tolerable doses of 5-FU and IFN-alpha were established for each patient. IFN-gamma was administered at one of six dose levels between 0.3-4.8 MU/m2 s.c. on days 1-7. This design permitted comparison of the clinical toxicity and pharmacokinetics of 5-FU in two consecutive cycles in an individual treated with the same doses of 5-FU/LV/IFN-alpha in the absence and presence of IFN-gamma. In 43 matched patient cycles, the addition of IFN-gamma did not seem to worsen gastrointestinal toxicity, and skin toxicity tended to be milder. 5-FU clearance was higher in 14 cycles with IFN-gamma compared to the patient's prior cycle with the same doses of 5-FU/LV/IFN-alpha: 798 +/- 309 versus 601 +/- 250 ml/min/m2 (mean +/- SD; P = 0.04). In these 28 cycles, the median 5-FU clearance was significantly lower in 11 cycles that were complicated by more severe diarrhea: 524 versus 798 ml/min/m2 (grade 2 versus 0-1; P = 0. 0032). Overall, 38% and 26% of patients had grade 3-4 diarrhea and mucositis. Dose reductions of IFN-gamma for chronic fatigue, malaise, or anorexia were ultimately required more frequently with >/=2.4 MU/m2 (P = 0.018), and the maximum tolerated dose of IFN-gamma was considered to be 1.2 MU/m2/ day. Objective responses were seen in 41% of 29 measurable colorectal cancer patients. Compared to our previous experience with 5-FU/LV/IFN-alpha, IFN-gamma and IFN-alpha appeared to have opposite effects on 5-FU clearance. These results suggest that any potential benefit of adding IFN-alpha to 5-FU/LV on this schedule may not depend solely on alterations in 5-FU clearance.  相似文献   
40.
We report the results of a consensus conference on the diagnosis of multiple system atrophy (MSA). We describe the clinical features of the disease, which include four domains: autonomic failure/urinary dysfunction, parkinsonism and cerebellar ataxia, and corticospinal dysfunction. We set criteria to define the relative importance of these features. The diagnosis of possible MSA requires one criterion plus two features from separate other domains. The diagnosis of probable MSA requires the criterion for autonomic failure/urinary dysfunction plus poorly levodopa responsive parkinsonism or cerebellar ataxia. The diagnosis of definite MSA requires pathological confirmation.  相似文献   
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