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The use of computer technology for patient education has increased in recent years. This article describes a study that measures the attitudes and perceptions of healthcare professionals and laypeople regarding the effectiveness of a multimedia computer, the Brain Injury Resource Center? (BIRC), as an educational tool. The study focused on three major themes: (a) usefulness of the information presented, (b) effectiveness of the multimedia touch-screen computer methodology, and (c) the appropriate time for making this resource available. This prospective study, conducted in an acute care medical center, obtained healthcare professionals' evaluations using a written survey and responses from patients with brain injury and their families during interviews. The findings have yielded excellent ratings as to the ease of understanding and usefulness of the BIRC. By using sight, sound, and touch, such a multimedia learning center has the potential to simplify patient and family education.  相似文献   
104.
Fibroblasts incorporated within collagen gels induce a cell-mediated contraction of the gel to form a three-dimensional, tissue-like structure by a mechanism thought to mimic wound contraction in vivo . In this study a gel contraction model was used to investigate the ability of fibroblasts derived from adult gingiva, adult skin and fetal skin to organise a collagen matrix. In addition the effects of interleukin-1β (IL-1β) on the contraction process was also investigated. Over the concentration range 5-50 U/ml, IL-1β induced a statistically significant inhibition of gel contraction in all fibroblast cell types ( P <0.05), although fetal fibroblasts appeared least responsive and gingival fibroblasts most responsive to the inhibitory effects of this cytokine. Comparison of gel contraction by the different fibroblast strains indicated that fetal and gingival fibroblasts shared similar contraction kinetics. For the adult skin fibroblasts, three of five strains studied showed significantly diminished levels of gel contraction compared to fetal and gingival cells. This apparent difference in fibroblast phenotype may, at least in part, explain the fetal-like wound healing pattern seen in the oral mucosa.  相似文献   
105.
A retrospective chart review of 43 patients who underwent technetium 99m (Tc-99m) sestamibi scans from June 1995 to January 1997 was performed. Only those who underwent subsequent parathyroid exploration with excision were included in the study. Twenty subjects (13 women and seven men) were included in the study. Ages ranged from 21 to 84 years (mean, 58 years). All patients had laboratory values and clinical findings consistent with primary hyperparathyroidism. Two patients had preoperative magnetic resonance imaging (MRI) scans (one patient with recurrent disease), and one had a preoperative computed tomography (CT) scan. The remaining patients had the sestamibi scan as the only preoperative localization study. There were 18 pathologic diagnoses of parathyroid adenoma and two of parathyroid hyperplasia. Sestamibi failed to correctly identify the location of the parathyroid lesion in two cases. In 18 cases the preoperative sestamibi scan correctly localized the lesion, a predictive value of 90%. We conclude that the Tc-99m sestamibi scan is an accurate preoperative tool that can be used as a single modality to localize parathyroid adenomas.  相似文献   
106.
Most prosthetic joint infections (PJI) are due to wound contamination at the time of surgery. Some infections occur due to the hematogenous spread of bacteria from distant sites of infection. A review of the literature fails to associate PJI with transient bacteremias from invasive dental procedures. Several authors have described conditions which, they believe, render patients with prosthetic joints more at risk for infection. Prosthetic joint patients with these "high risk" conditions have the same types of infecting organisms as other patients with PJI. This indicates that the infecting bacteria are from wound contamination or distant sites of infection and not related to dental procedure bacteremias. Based on this review, antibiotic prophylaxis is not indicated for patients with prosthetic joints when receiving invasive dental procedures, since there is no proven benefit and there are known risks involved with the use of antibiotics. However, the American Dental Association (ADA) and the American Academy of Orthopaedic Surgeons (AAOS), in an advisory statement, suggest prophylaxis for "high risk" patients. The ADA and AAOS recommend a single dose of amoxicillin, cephradine, or clindamycin when prophylaxis is selected. The dentist is ultimately responsible for making treatment recommendations for his or her patients.  相似文献   
107.
The value of ultrasound in the diagnosis of a large rapidly growing thyroid mass was assessed in a study of 42 patients with a large (> 3 cm) rapidly growing (< two months) solitary mass. Haemorrhage into a thyroid nodule was present in 31 patients and thyroid malignancy in 11. Ultrasound of haemorrhage into a thyroid nodule revealed a large cystic mass in all 31 patients containing internal debris (22), septations (three), or a combination of both (six). The malignant causes of a large rapidly growing mass were lymphoma (two), anaplastic carcinoma (four) and metastasis (five). Ultrasound of these thyroid malignancies revealed a mass with a smooth, well-defined margin and strikingly low homogeneous echogenicity in all cases. Patients with thyroid metastases had evidence of widespread metastatic disease elsewhere. Lymphoma was differentiated from anaplastic carcinoma on fine-needle aspiration cytology or surgical biopsy. Ultrasound was of value in differentiating between a benign haemorrhagic nodule and a malignant tumour. The various malignant tumours had similar appearances, however, and could not be distinguished on ultrasound.  相似文献   
108.
Low signal intensity on long-repetition-time MR sequences has been observed in deep gray matter structures in patients with multiple sclerosis. This T2 shortening most likely represents a nonspecific degenerative process. We recently observed T2 shortening in the pericentral cortical gray matter and subcortical white matter in a patient with severe multiple sclerosis and we postulate that this represents an additional manifestation of neural degeneration.  相似文献   
109.
With pulsed X-ray cinematography we have analysed the angular excursions of the distal hindlimb joints (proximal interphalangeal, PIP; metatarsophalangeal, MTP; ankle) in cats walking on a treadmill. These distal joints transmit the body weight and the dynamic forces onto the ground. We have included the knee and hip joints in the analysis to relate the angular excursions of the proximal and distal joints and to verify the data previously obtained with external markers on the kinematics of the proximal joints. At the beginning of the stance phase the PIP joints flexed rapidly, the MTP joints extended slowly and the ankle and knee yielded under body weight. Whereas the PIP joints maintained a rather constant angular position of −75° throughout the stance phase, extension continued in the MTP joints from −230° at touch-down to −270° at the end of the stance phase. Around 50 ms before lift-off the MTP joints flexed rapidly. Early (−30 ms) after lift-off this flexion changed into a slow extension. The PIP joints extended swiftly at the stance-swing transition and moderately at the end of the swing phase. During the middle part of the swing phase they flexed slowly. Small rotatory movements around the long axis of the foot took place in the last 100 ms of the swing phase. The results of this study on the distal joints are discussed in relation to the placing of the paw, to the translation of forward propulsion into a MTP movement and to the lifting of the paw (conventionally described as toe curling). They show a differentiated mechanical interaction between the different distal limb joints during these different phases, which must be known in detail to interpret the corresponding electromyographic data and to understand how the hip is moved forward over the MTP joints which serve as the final pivot during stance.  相似文献   
110.
In 41 patients with recurrent sustained ventricular tachycardia and/or ventricular fibrillation an integrated pacemaker-defibrillator-system (PCD, Medtronic, model 7216 A or 7217 B) was implanted. In 21 out of 24 (88%) patients a new transvenous implantation technique in combination with a subcutaneous patch electrode was used. The implanted devices comprise antibradycardiac pacemaker functions, two different forms of antitachycardiac pacemaker functions (ramp and burst pacing), and internal cardioversion or defibrillation capabilities. During a mean follow-up of 8 months 147 episodes of ventricular tachycardia were detected, 131 of them were terminated successfully by antitachycardiac pacing; in 13 episodes internal cardioversion was applied to revert ventricular tachycardia. Twenty-seven episodes of ventricular fibrillation or rapid ventricular tachycardia (greater than 200/min) were detected and successfully terminated by internal defibrillation. In six patients with intermittent rapid atrial fibrillation, change of antiarrhythmic therapy was required to avoid activation of the device. The new integrated pacemaker-defibrillator systems improve therapy in patients with life-threatening tachyarrhythmias by reducing the number of internal cardioversions/defibrillations; the non-thoracotomy approach reduces the post operative risk.  相似文献   
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