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1.
Objective: Shoulder pain after spinal cord injury (SCI) is attributed to increased mobility demands on the arms and negatively impacts independence and quality of life. Repetitive superior and posterior shoulder joint forces produced during traditional wheelchair (WC) locomotion can result in subacromial impingement if unopposed, as with muscular fatigue or weakness. ROWHEELS® (RW), geared rear wheels that produce forward WC movement with backward rim pulling, could alter these forces.

Design: Cross sectional.

Setting: Research laboratory at a rehabilitation hospital.

Participants: Ten manual WC users with paraplegia.

Outcome measures: Propulsion characteristics and right upper extremity/trunk kinematics and shoulder muscle activity were collected during ergometer propulsion: (1) self-selected free speed reverse propulsion with RW, (2) matched-speed reverse (rSW), and (3) forward propulsion (fSW) with instrumented Smartwheels (SW). Inverse dynamics using right-side SW rim kinetics and kinematics compared shoulder kinetics during rSW and fSW.

Results: Free propulsion velocity, cycle distance and cadence were similar during RW, rSW and fSW. Overall shoulder motion was similar except that peak shoulder extension was significantly reduced in both RW and rSW versus fSW. Anteriorly and inferiorly directed SW rim forces were decreased during rSW versus fSW propulsion, but posteriorly and superiorly directed rim forces were significantly greater. Superior and posterior shoulder joint forces and flexor, adductor, and external rotation moments were significantly less during rSW, without a significant difference in net shoulder forces and moments. Traditional propulsive-phase muscle activity was significantly reduced and recovery-phase muscle activity was increased during reverse propulsion.

Conclusion: These results suggest that reverse propulsion may redirect shoulder demands and prevent subacromial impingement, thereby preventing injury and preserving independent mobility for individuals with paraplegia.  相似文献   
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The need for rapid and accurate retrieval of the data generated by an oral biopsy service and the adjacent medical center was met with the purchase and programming of a microcomputer and hard disk drive. The planning phase involved an assessment of the needs of the department, creation of an ideal form to be displayed on the video screen that can be easily used to enter the information, selection of coding systems, and selection of compatible hardware and software. Customized in-house programming using a commercially available database management system has created an entry form and menu-driven information retrieval system tailored to the needs of the department.  相似文献   
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Objective:  Determination of the microflora present on the tongue dorsum of subjects with and without halitosis using conventional microbiological culture methods.
Methods:  Twenty-one halitosis and 20 control patients were recruited using a strict clinical protocol. Samples were collected from the posterior dorsum of the tongue using a sterile brush. Each sample was vortex mixed for 30 s and serial 10-fold dilutions to 10−7 were carried out. Samples were plated onto fastidious anaerobe agar (FAA) and FAA enriched with vancomycin. These were incubated under anaerobic conditions for 10 days at 37°C. Strict anaerobes were identified by metronidazole sensitivity and bacteria were identified to genus level by a combination of colony morphology, Gram staining and biochemical and enzymatic tests (rapid ID 32 A).
Results:  The predominant species in test and control groups were Veillonella sp. and Prevotella sp. Greater species diversity was found in the halitosis samples compared with controls. The halitosis samples contained an increased incidence of unidentifiable Gram-negative rods, Gram-positive rods and Gram-negative coccobacilli.
Conclusions:  There was no obvious association between halitosis and any specific bacterial genus. The increased species diversity found in halitosis samples suggests that halitosis may be the result of complex interactions between several bacterial species. The role of uncultivable bacteria may also be important in contributing to this process.  相似文献   
4.
Patients' preferences for dentists' behaviors   总被引:1,自引:0,他引:1  
Unlike previous studies that examined specialized populations or were completed some years ago, this survey collected information from a cross-section of patients who were currently receiving various kinds of dental treatment. Although the study disclosed that patients' preferences and perceptions of dentists' performance might vary within and between demographic groups, a more important finding was that, in general, most patients in all demographic groups held common beliefs about how they would like to be treated by their dentists. However, according to the reports of these patients, the dentists did not always behave in ways that were congruent with the patients' preferences. The study showed that patients are sensitive to dentists' behaviors. It should also be noted that dentists are sensitive to patients' behaviors and that dentist-patient relationships may be a source of stress for both patients and dentists. Nevertheless, the responsibility for setting the tone of these relationships rests primarily with the dentist rather than with the patient. Therefore, it is important for dentists to be aware of the needs and preferences of their patients so that they can act in ways that will make patients comfortable and dental treatment a positive experience. The potential that appears to be inherent in good, satisfying dentist-patient relationships for minimizing patient stress and making dentistry a less stressful profession has yet to be fully realized. Dentistry is a two-way street: whatever benefits the patient should in turn benefit the dentist as well.  相似文献   
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A system is described in which the volume flow rate of blood in a vessel is determined using transverse colour Doppler ultrasound imaging. The system measures rapidly the two-dimensional velocity profile of blood flowing through a vessel. By integration of the measured velocity profiles the volume flow rate of blood in the vessel is obtained. The Doppler angle is obtained from the included angle between two imaging planes, and their respective average measured flows. This technique yields instantaneous and average flow rate in real time, and permits long flow recordings to be made and stored digitally. The error is less than 5% over a 8:1 flow rate range.  相似文献   
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