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91.
The clinical goal of spinal fusion is to reduce motion and the associated pain. Therefore, measuring motion under loading is critical. The purpose of this study was to validate four-point bending as a means to mechanically evaluate simulated fusions in dog and rabbit spines. We hypothesized that this method would be more sensitive than manual palpation and would be able to distinguish unilateral vs bilateral fusion. Spines from four mixed breed dogs and four New Zealand white rabbits were used to simulate posterolateral fusion with polymethyl methacrylate as the fusion mass. We performed manual palpation and nondestructive mechanical testing in four-point bending in four planes of motion: flexion, extension, and right and left bending. This testing protocol was used for each specimen in three fusion modes: intact, unilateral, and bilateral fusion. Under manual palpation, all intact spines were rated as not fused, and all unilateral and bilateral simulated fusions were rated as fused. In four-point bending, dog spines were significantly stiffer after unilateral fusion compared with intact in all directions. Additionally, rabbit spines were stiffer in flexion and left bending after unilateral fusion. All specimens exhibited significant differences between intact and bilateral fusion except the rabbit in extension. For unilateral vs bilateral fusion, significant differences were present for right bending in the dog model and for flexion in the rabbit. Unilateral fusion can provide enough stability to constitute a fused grade by manual palpation but may not provide structural stiffness comparable to bilateral fusion.  相似文献   
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This study evaluated the effectiveness of early orthodontic treatment with the Twin-block appliance for the developing Class II Division 1 malocclusion. This multicenter trial was carried out in the United Kingdom. A total of 174 children, aged 8 to 10 years old, with Class II Division 1 malocclusion were randomly allocated to receive treatment with a Twin-block appliance or to an untreated, control group. Data were collected at the start of the study and 15 months later. Results showed that early treatment with Twin-block appliances resulted in reduction of overjet, correction of molar relationships, and reduction in severity of malocclusion. Most of this correction was due to dentoalveolar change, but some was due to favorable skeletal change. Early treatment with the Twin-block appliance is effective in reducing overjet and severity of malocclusion. The small change in the skeletal relationship might not be considered clinically significant.  相似文献   
95.
BACKGROUND: Recently, epidemiological and clinical data have revealed important changes with regard to clinical adenovirus infection, including alterations in antigenic presentation, geographical distribution, and virulence of the virus. METHODS: In an effort to better understand the epidemiology of clinical adenovirus infection in the United States, we adopted a new molecular adenovirus typing technique to study clinical adenovirus isolates collected from 22 medical facilities over a 25-month period during 2004-2006. A hexon gene sequence typing method was used to characterize 2237 clinical adenovirus-positive specimens, comparing their sequences with those of the 51 currently recognized prototype human adenovirus strains. In a blinded comparison, this method performed well and was much faster than the classic serologic typing method. RESULTS: Among civilians, the most prevalent adenovirus types were types 3 (prevalence, 34.6%), 2 (24.3%), 1 (17.7%), and 5 (5.3%). Among military trainees, the most prevalent types were types 4 (prevalence, 92.8%), 3 (2.6%), and 21 (2.4%). CONCLUSIONS: For both populations, we observed a statistically significant increasing trend of adenovirus type 21 detection over time. Among adenovirus isolates recovered from specimens from civilians, 50% were associated with hospitalization, 19.6% with a chronic disease condition, 11% with a bone marrow or solid organ transplantation, 7.4% with intensive care unit stay, and 4.2% with a cancer diagnosis. Multivariable risk factor modeling for adenovirus disease severity found that age <7 years (odds ratio [OR], 3.2; 95% confidence interval [CI], 1.4-7.4), chronic disease (OR, 3.6; 95% CI, 2.6-5.1), recent transplantation (OR, 2.7; 95% CI, 1.3-5.2), and adenovirus type 5 (OR, 2.7; 95% CI, 1.5-4.7) or type 21 infection (OR, 7.6; 95% CI, 2.6-22.3) increased the risk of severe disease.  相似文献   
96.
Deb Miller  RN  BS  CNOR 《AORN journal》2002,76(5):898
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97.
Management of an indeterminate pulmonary nodule is a diagnostic challenge that commonly confronts primary care physicians and specialists. Patients often present with this radiographic finding in the course of an unrelated medical evaluation. We examined our institution's experience with percutaneous biopsy of lung nodules to determine the impact of this procedure on overall patient care. Although significant complications are uncommon, the expedience of percutaneous lung biopsy often supplants a surgical opinion prior to initiation of therapy without added diagnostic benefit or cost-savings. Hence, we caution practitioners to use this technique as an adjunct to diagnosis and not a substitute for multidisciplinary care.  相似文献   
98.
Adult wound repair occurs with an initial inflammatory response, reepithelialization, and the formation of a permanent scar. Although the inflammatory phase is often considered a necessity for successful adult wound healing, fetal healing studies have shown the ability to regenerate skin and to heal wounds in a scarless manner in the absence of inflammation. The cyclooxygenase-2 (COX-2) enzyme, a known mediator of inflammation, has been shown to contribute to a variety of inflammatory conditions and to the development of cancer in many organs. To examine the role of COX-2 in the wound healing process, incisional wounds were treated topically with the anti-inflammatory COX-2 inhibitor celecoxib. Acutely, celecoxib inhibited several parameters of inflammation in the wound site. This decrease in the early inflammatory phase of wound healing had a significant effect on later events in the wound healing process, namely a reduction in scar tissue formation, without disrupting reepithelialization or decreasing tensile strength. Our data suggest that in the absence of infection, adult wound healing is able to commence with decreased inflammation and that anti-inflammatory drugs may be used to improve the outcome of the repair process in the skin by limiting scar formation.  相似文献   
99.
Akathisia as a side-effect of metoclopramide has received increasing attention in consultation-liaison psychiatry in recent years. A case of metoclopramide-induced akathisia resulting in a suicide attempt is reported in order to highlight the suffering of such patients and the factors that lead to misdiagnosis.  相似文献   
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