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61.
Objective. Bone infarction (BI) of the calcaneus is an uncommon entity which has received little mention in the recent literature. In
this paper, we review the MR images of six calcanei with BI, which demonstrate a pattern of presentation that may explain
the etiology of BI at this unusual location. Design. A retrospective review was performed of the transcribed reports of the foot or ankle MR examinations at our institution.
MR images of examinations with any marrow signal abnormality were reviewed for presence of BI and its distribution. Patients. Based on MRI criteria, four patients had calcaneal BI (none biopsy proven); they ranged in age from 37 to 51 years old. Two
patients were diagnosed with systemic lupus erythematosus, one with fibrositis, and another with polymyositis. All were treated
with corticosteroids. Results. Six calcanei (in four patients) contained a region of calcaneal BI. In five of the six, the lesions were entirely or predominantly
located in the posterior half of the calcaneus. Conclusion. Two theories are proposed which may explain why BI predominantly occurs in the posterior half of the calcaneus. First, the
convergence of the recurrent intraosseous calcaneal vessels may occasionally produce the equivalent of a single dominant vessel
that is more prone to vascular accidents. Secondly, the region between the recurrent and the epiphyseal vessels may act as
a watershed zone, increasing its susceptibility to ischemia. 相似文献
62.
Studies of clinical teaching roles have not appeared in the athletic training literature. The purposes of this study were to: 1) describe clinical teaching roles of Midwest ATCs, and 2) determine the effect of educational preparation on teaching activities and opinions of ATCs. A three-part questionnaire was returned by 154 ATCs (78%) in NATA District 5. The questionnaire included demographic, teaching, and opinion items. More than 50% of the ATCs were teacher-certified and the majority had a master's or higher degree. Most ATCs clinically supervised between one to eight students who received clinical instruction about 20 hours weekly. The ATCs who taught clinically either presented information or directed tasks from five to six Role Delineation Domains. They used three or more teaching methods and six or more audiovisual aids with their presentations. The ATCs saw the importance of clinical education and the responsibility to present clinical information, and expressed positive opinions about academic preparation for clinical teaching. Those with teaching degrees felt more prepared to teach (p<.05) than did nonteachers. Teachers conducted clinical teaching activities similar to nonteachers. We concluded that less experienced athletic trainers feel educationally prepared and enjoy clinical teaching as much as their more experienced peers. The ATCs with a teaching background presented a broader content through more mature teaching methods than did nonteachers. It appeared that adequate preparation for teaching and the attainment of an advanced degree may inspire confidence in clinical teaching. These attributes may become important characteristics to look for when recruiting clinical instructors. 相似文献
63.
Spahn Hildegard Iwakawa Seigo Lin Emil T. Benet Leslie Z. 《Pharmaceutical research》1989,6(2):125-132
The diastereoisomeric glucuronic acid conjugates of R/S-benoxaprofen are the major benoxaprofen metabolites and are found in urine at high concentrations. The conjugates of R- and S-benoxaprofen can be separated directly on a C18 reversed-phase column using a mixture of acetonitrile and tetrabutylammonium hydroxide buffer, pH 2.5 (28:72, v/v), as the mobile phase. The k values of S- and R-benoxaprofen glucuronides are 57.5 and 63.0, respectively. Diluted urine or deproteinized plasma samples were injected without further treatment. With fluorescence detection at 313/365 nm, quantifiable limits of 50 ng equiv./ml were found for the conjugates. The intra- and interday variability was below 12%. Utilizing this analytical procedure it is possible to characterize enantioselective glucuronidation both in vivo and in vitro. For in vitro procedures, apparent rates of formation and the R/S ratio may be substrate (benoxaprofen) and cosubstrate (UDPGA) dependent. Moreover, enantioselective cleavage of the formed benoxaprofen glucuronides by alkaline hydrolysis, hydrolytic enzymes, and acyl migration must be controlled for both in vitro and in vivo studies since R-benoxaprofen glucuronide is degraded faster than the S-diastereomer under certain conditions. 相似文献
64.
With the rise in chronic, behavior-related disease, computerized behavioral protocols (CBPs) that help individuals improve behaviors have the potential to play an increasing role in the future health of society. To be effective and widely used CBPs should be based on accepted behavioral theory. However, designing CBPs while at the same time specifying their linkages to behavioral theory and developing reusable CBP components (interventions) are challenges to developers of CBPs. Having an ontology with which to describe CBPs could help with these issues. As a first step towards creating such an ontology, we modeled PACE-Adolescent, a theory-based behavioral protocol that uses the Stages of Change Model and Social Cognitive Theory, using PROTEGE-2000, an ontology editor and knowledge acquisition system. We created a three-part knowledge model. Two sub-ontologies described behavioral interventions and psychological theories. The third component, implemented using Guideline Interchange Format (GLIF3), provided a way to describe the structure of a protocol and to link intervention resources and groups of actions to elements of psychological theory. Using this framework, we formally described the PACE-Adolescent protocol. Creating knowledge models such as this may lead to improvements in the design and evaluation of computerized health behavior protocols. 相似文献
65.
66.
Elliott L Heederik D Marshall S Peden D Loomis D 《The Journal of allergy and clinical immunology》2005,116(1):127-132
BACKGROUND: Laboratory animal allergy is a common illness among workers exposed to laboratory animals and can progress to symptoms of asthma. OBJECTIVES: This study evaluates the continuum of disease from allergy symptoms to asthma symptoms in a dynamic cohort of workers exposed to animals in a pharmaceutical company. METHODS: Data arose from annual questionnaires administered to workers in a surveillance program established to monitor exposure to animals and the development of allergy. The life-table method was used to compare asthma-free survival between workers with and without symptoms of allergy. A Cox proportional hazards model was used to examine the effects of covariates on the development of asthma. RESULTS: A total of 603 workers contributed 2527.4 person-years to the study over the 12.3-year period. The probabilities of experiencing asthma symptoms by the 11th year of follow-up were 0.367 for workers with allergy symptoms and 0.052 for those without allergy symptoms. The hazard ratio for asthma symptoms when comparing workers with and without allergy symptoms was 7.39 (95% CI, 3.29-16.60) after adjustment for sex and family history of allergy. Female subjects developed asthma at a rate 3.4 times that of male subjects. CONCLUSIONS: This study supports the hypothesis that laboratory animal allergy symptoms are a major risk factor for the development of asthma. It also suggests a heightened risk of asthma for women who work with laboratory animals, a finding that has not been previously reported. 相似文献
67.
Diagnosis of gastrointestinal stromal tumors: A consensus approach 总被引:258,自引:0,他引:258
Fletcher CD Berman JJ Corless C Gorstein F Lasota J Longley BJ Miettinen M O'Leary TJ Remotti H Rubin BP Shmookler B Sobin LH Weiss SW 《Human pathology》2002,33(5):459-465
As a result of major recent advances in understanding the biology of gastrointestinal stromal tumors (GISTs), specifically recognition of the central role of activating KIT mutations and associated KIT protein expression in these lesions, and the development of novel and effective therapy for GISTs using the receptor tyrosine kinase inhibitor STI-571, these tumors have become the focus of considerable attention by pathologists, clinicians, and patients. Stromal/mesenchymal tumors of the gastrointestinal tract have long been a source of confusion and controversy with regard to classification, line(s) of differentiation, and prognostication. Characterization of the KIT pathway and its phenotypic implications has helped to resolve some but not all of these issues. Given the now critical role of accurate and reproducible pathologic diagnosis in ensuring appropriate treatment for patients with GIST, the National Institutes of Health convened a GIST workshop in April 2001 with the goal of developing a consensus approach to diagnosis and morphologic prognostication. Key elements of the consensus, as described herein, are the defining role of KIT immunopositivity in diagnosis and a proposed scheme for estimating metastatic risk in these lesions, based on tumor size and mitotic count, recognizing that it is probably unwise to use the definitive term "benign" for any GIST, at least at the present time. 相似文献
68.
69.
Integrating complementary and alternative medicine instruction into health professions education: organizational and instructional strategies. 总被引:1,自引:0,他引:1
Mary Y Lee Rita Benn Leslie Wimsatt Jane Cornman Joan Hedgecock Susan Gerik Janice Zeller Mary Jo Kreitzer Pamela Allweiss Claudia Finklestein Aviad Haramati 《Academic medicine》2007,82(10):939-945
A few years ago, the National Institutes of Health National Center for Complementary and Alternative Medicine funded a program called the Complementary and Alternative Medicine (CAM) Education Project. Grantees were 14 medical and nursing schools and the American Medical Student Association, which funded six additional medical schools. Grants were awarded in cohorts of five per year in 2000, 2001, and 2002-2003.The R25 grant recipients identified several major themes as crucial to the success of integrating CAM into health professions curricula. The rationale for integrating CAM curricula was in part to enable future health professionals to provide informed advice as patients dramatically increase the use of CAM. Success of new CAM education programs relied on leadership, including top-down support from institutions' highest administrators. Formal and informal engagement of key faculty and opinion leaders raised awareness, interest, and participation in programs. A range of faculty development efforts increased CAM-teaching capacity. The most effective strategies for integration addressed a key curriculum need and used some form of evidence-based practice framework. Most programs used a combination of instructional delivery strategies, including experiential components and online resources, to address the needs of learners while promoting a high level of ongoing interest in CAM topics. Institutions noted several benefits, including increased faculty development activities, the creation of new programs, and increased cross- and inter-university collaborations. Common challenges included the need for qualified faculty, crowded and changing curricula, a lack of defined best practices in CAM, and post-grant sustainability of programs. 相似文献
70.
Frauke Behrens Uwe Claussen Leslie M. Iyer Eric D. Green Bernhard Horsthemke Robert Williamson Clare Huxley Charles Coutelle 《Chromosome research》1997,5(4):215-220
Centromeres remain the least characterized regions of human chromosomes because they have a very high content of repetitive DNA. Here, we describe a micro-dissection library from the centromeric region of human chromosome 7 and its use for generating sequence tagged sites (STSs). The library contains about 1500 clones with an average insert size of 150 bp and only about 15% of the clones harbour repetitive human DNA. Seven clones hybridizing to alphoid DNA were found to correspond to a fragment of the D7Z2 alphoid array on chromosome 7, thus confirming the origin of the library. A number of clones not containing known repetitive DNA were used to generate STSs that identified yeast artificial chromosomes (YACs) and in turn allowed the STSs to be placed on the physical map. One STS is located between the two Genethon genetic markers closest to the centromere on the q side. Another STS was located 3–4 cM away in 7q11.2, while a third identified YACs containing both low-copy and alphoid sequences that are not yet mapped but are clearly centromeric. The library therefore comprises a collection of sequences from the centromeric region of chromosome 7 that can be used to generate STSs and to map the entire centromeric region.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献