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排序方式: 共有2241条查询结果,搜索用时 15 毫秒
1.
The Usefulness of Magnetic Resonance Imaging in the Diagnosis of Anterolateral Impingement of the Ankle 总被引:3,自引:0,他引:3
LCDR Doug Duncan MD CAPT Tim Mologne MD CDR Hans Hildebrand MD Mark Stanley MD LT Richard Schreckengaust MD CAPT Dave Sitler MD 《The Journal of foot and ankle surgery》2006,45(5):304-307
The purpose of this study is to assess the sensitivity and specificity of magnetic resonance imaging (MRI) in the diagnosis of anterolateral impingement of the ankle and to assess the most helpful sequence in making the diagnosis. Twenty-four patients who had undergone ankle arthroscopy were chosen. Twelve patients had arthroscopically documented anterolateral impingement, and 12 patients with no impingement on arthroscopy served as controls. Two musculoskeletal radiologists and an orthopedic surgeon, blinded to the operative diagnosis, retrospectively reviewed selective MRI images in the sagittal, axial, and coronal planes. The sensitivities and specificities were calculated for all 3 reviewers. The Kendall coefficient of concordance was calculated for overall agreement among reviewers. Sensitivities varied from 0.75 to 0.83, whereas specificities varied from 0.75 to 1.00. Using the Fisher exact test of contingency, the sensitivities and specificities showed that all reviewers' interpretations were statistically significant with P = .039, .001, and .012, respectively. The axial images were felt to be most helpful in making the diagnosis. The physicians felt that the sagittal images were helpful in 67%, 83%, and 100%, respectively. MRI is a useful tool that can aid the clinician in the diagnosis of anterolateral impingement of the ankle. T1 sagittal images demonstrating displacement of the normal fat signal anterior to the fibula by scar can be useful and help to confirm the diagnosis. 相似文献
2.
CPT Tony Pierson Jeffrey A. Niezgoda MD LT Sarah Learmonth CPT Dennis Blunt LTC Kevin McNabb 《Wound repair and regeneration》2005,13(2):1-2
Abstract Brooke Army Medical Center isolated 25 highly antibiotic‐resistant Acinetobacter ssp . (primarily A. baumannii ) from wounded soldiers returning from Iraq. Concern about effective treatment of these organisms led our institution to begin investigating low‐frequency ultrasound (LFU) as a method of increasing the effectiveness of antibiotics on A.baumannii in wound management. Studies have suggested that LFU applied in conjunction with antibiotics may increase their overall effectiveness. We hypothesize that combining antibiotics with LFU may be an effective method of wound management and that this combination may be synergistic in its overall effect. In this initial work, we wanted to determine if sonocation would have an effect on our organism of interest, A. baumannii . We selected several organisms, both gram positive and gram negative, that have been shown to be killed by sonocation ( E. coli, S. aureus , and S. pyogenes ) and added three highly resistant A. baumannii isolates. Bacterial death was measured by both colony counts after 24 hours of growth and acridine orange staining using a standard protocol.
Colony counts were significantly reduced by sonocation. Furthermore, A.'baumannii colony counts were also greatly reduced by sonocation. Actual cell destruction was also visualized using acridine orange staining. Our data support the assertion that sonocation has an antibacterial effect on some bacteria, including A. baumannii . Our next step is to add antimicrobial agents and determine if their effectiveness can be increased by sonocation. 相似文献
Colony counts were significantly reduced by sonocation. Furthermore, A.'baumannii colony counts were also greatly reduced by sonocation. Actual cell destruction was also visualized using acridine orange staining. Our data support the assertion that sonocation has an antibacterial effect on some bacteria, including A. baumannii . Our next step is to add antimicrobial agents and determine if their effectiveness can be increased by sonocation. 相似文献
3.
4.
CG Teo 《Oral diseases》2002,8(S2):88-90
Oral hairy leukoplakia (OHL) and Kaposi's sarcoma (KS) are commonly encountered in the HIV-infected patient. A unique feature of OHL is non-cytolytic high level of replication of Epstein–Barr virus (EBV) in the glossal epithelium. The expression of viral-encoded anti-apoptotic proteins concomitant to replicative proteins probably underlies this phenomenon. The question of whether OHL arises from activation of EBV latent in the tongue, or from superinfection by endogenous EBV shed via non-glossal sites or by exogenous EBV remains unresolved. Human herpesvirus 8 (HHV8) is now seen as necessary but not sufficient cause of KS. Expression of HHV8-encoded oncogenic proteins in endothelial cells probably explains the aberrant proliferation of these cells in KS lesions. Studies into why KS is so commonly observed at the palate in HIV-infected patients may provide important clues to its pathogenesis. 相似文献
5.
A sciatic nerve lesion is uncommon. We report the utility of the endoscope in an 18-year-old female with multiple lesions of her sciatic nerve. Somatosensory evoked potentials and MRI were indicative of a sciatic nerve lesion. We describe a simple technique of endoscopic exploration of the sciatic nerve to assist intraoperative decision making. 相似文献
6.
J. S. ERJEFÄLT M. KORSGREN M. C. NILSSON F. SUNDLER C. G. A. PERSSON† 《Clinical and experimental allergy》1997,27(11):1344-1355
Background Associations between allergen challenge-induced sites of epithelial damage and the distribution of leucocytes and extravasated plasma remain unexplored. Objective To study neutrophils, eosinophils, and fibrinogen at allergen challenge-induced patchy epithelial damage-restitution sites in guinea-pig trachea. Methods After local challenge tracheal tissue (cryo sections and whole-mounts) and lumen (selective tracheal lavage) were examined at 1, 5, and 24 h. Eosinophils, neutrophils and fibrinogen were identified by histochemistry. Results Neutrophils increased markedly in tracheal lavage fluids and in tissue and were strongly associated with the challenge-induced epithelial craters of damage-restitution. At 1 and 24 h eosinophils were increased in the tracheal lumen whereas the surrounding tissue displayed a reversed pattern. Gels rich in fibrinogen, neutrophils, and eosinophils were present in epithelial crater areas, protruding into the lumen. Clusters of free eosinophil granules, Cfegs, released through lysis of eosinophils, and neutrophils with long cytoplasmatic protrusions abounded in these crater areas. Conclusions The present findings provide important new insights into allergic airways where sites of epithelial damage-restitution processes emerge as the major loci for eosinophil, neutrophil, and plasma protein activities, the latter likely causing leukocyte adhesion and activation in vivo. The disttibution of eosinophils in this study suggests roles of these cells both in airway mucosa and in regional lymph nodes. Based on the present study we also propose that lysis of eosinophils and Cfegs generation are a major paradigm for activation of these cells in vivo. 相似文献
7.
Despite empirical evidence that cardiac rehabilitation programs can play a significant role in enhancing recovery following a primary cardiac event and in enacting secondary prevention measures, attendance rates remain remarkably low. Referral and attendance at cardiac rehabilitation programs are not one and the same. Recognizing this, issues related to the referral of eligible patients to cardiac rehabilitation and factors that affect patients' decisions regarding attendance must be identified and addressed. This article presents an overview of the potential benefits of cardiac rehabilitation programs, describes salient issues related to referral and attendance, and identifies directions for future research. 相似文献
8.
A J Buckton R Kulasegaram S L Ngui M Fisher R James S Rangarajan C G Teo 《Journal of clinical virology》2007,40(1):60-63
An HIV-1/hepatitis C virus (HCV) co-infected patient with haemophilia received a 48-week course of pegylated interferon-alpha-2b and ribavirin therapy for genotype 5a HCV infection. Virological response was achieved at week 24. At the end of treatment, HCV RNA in serum was detected and identified to belong to genotype 2b, rather than genotype 5a. A sensitive method for identifying minority HCV genotypes in pre-treatment serum showed genotype 2b HCV carriage prior to treatment. Sequencing the interferon sensitivity-determining region of the HCV NS5A gene obtained from pre-, intra- and post-treatment sera revealed emergence of quasispecies bearing R-->K and M-->A/T mutations at codons 2222 and 2223, respectively. Occult presence of minority HCV subpopulations and their acquisition of mutations following therapy can result in poor treatment outcome. 相似文献
9.
Thymidine phosphorylase expression and stromal vascularity in ductal carcinoma in situ of the breast
AIMS: Periductal angiogenesis in ductal carcinoma in situ is associated with an increased risk of subsequently developing a recurrence. This study aimed to (1) identify the relation between periductal and stromal vascularity and recurrence and (2) determine whether thymidine phosphorylase (TP) is associated with angiogenesis or recurrence in ductal carcinoma in situ (DCIS). METHODS: Twenty cases of DCIS that did not subsequently recur, 20 that developed a subsequent in situ recurrence, and 12 that developed a subsequent invasive recurrence were investigated. Periductal and stromal (hotspot) microvessel density were determined quantitatively using antibodies to CD34 and von Willebrandt factor (vWF). TP expression by DCIS was assessed semiquantitatively using the H score method. RESULTS: Stromal and periductal microvessel density assessed by anti-vWF gave similar mean values, and showed a strong positive correlation. When angiogenesis was assessed with anti-CD34 this association was lost. Not only were the mean values for both types of microvessel density higher than those obtained with anti-vWF, but the periductal microvessel density was significantly greater than the stromal microvessel density. TP expression was associated with stromal microvessel density assessed with anti-vWF, but not with anti-CD34. TP expression was not related to recurrence. No significant difference was identified in TP expression or stromal vascularity in DCIS between cases that recurred as DCIS and those that recurred as invasive carcinoma. CONCLUSIONS: Recurrent in situ or invasive disease after excision of DCIS does not appear to be related to stromal microvessel density or to TP expression by DCIS cells. 相似文献