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21.
OBJECTIVE: We wanted to determine whether the standard three-view ankle radiographic series could be replaced by a two-view combination, and if so, which two-view combination (anteroposterior with lateral or mortise with lateral) would be superior. MATERIALS AND METHODS: During a 12-month period, we retrospectively reviewed 556 consecutive ankle radiographic studies consisting of anteroposterior, mortise, and lateral views. One hundred twenty patients with at least one ankle fracture were paired with 140 healthy control subjects. Each image in the three-view examination was separated and sorted by view and studied independently; all images were reviewed by two skeletal radiologists and two orthopedic surgeons. Each radiograph was evaluated for fracture of the medial, lateral, and posterior malleoli and the foot using a five-point confidence rating. Performance of each view and modeled two- and three-view combinations of views was evaluated with modified receiver operating characteristic analysis. RESULTS: The data provide little support for preferring either two-view combination (anteroposterior-lateral or mortise-lateral) for any type of fracture. The three-view combination does detect significantly more fractures than some two-view combinations in some locations, and there is a statistically significant cost in diagnostic accuracy for eliminating the anteroposterior or mortise view. CONCLUSION: Reducing the ankle radiographic series from three to two views would result in a small but significant decrease in the detection of fractures of the ankle and foot. Both two-view combinations are equivalent for fracture detection.  相似文献   
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PURPOSE: Epstein-Barr virus (EBV) in Hodgkin's lymphoma (HL) cells has been considered as a prognostic marker for this heterogeneous disease, but studies have yielded mixed findings, likely because of selected patient series and failure to acknowledge an effect of age on outcome. This study assessed survival after HL in a population-based cohort large enough to examine the joint effects of EBV with other factors including age, sex, and histologic subtype. PATIENTS AND METHODS: Included were 922 patients with classical HL diagnosed between mid-1988 and 1997 in the Greater San Francisco Bay Area, with archived biopsy specimens assayed for EBV with immunohistochemistry and in situ hybridization. Vital status was followed through December 30, 2003 (median follow-up time, 97 months). Overall and disease-specific survival were analyzed with the Kaplan-Meier method and Cox proportional hazards regression models. RESULTS: In children less than 15 years old, EBV presence was suggestively associated (P = .07) with favorable survival. In adults aged 15 to 44 years, EBV did not affect HL outcome, although a protective effect was suggested. In older adults (45 to 96 years), EBV presence nearly doubled the risk of overall and HL-specific mortality but only for patients with nodular sclerosis (NS) histologic subtype (hazard ratio for death = 2.5; 95% CI, 1.5 to 4.3). CONCLUSION: In HL, EBV tumor cell presence is associated with better survival in young patients and poorer survival in older patients with NS, independent of other factors. Variation in outcome by age and histology could indicate biologically distinct disease entities. Evidence that EBV is a meaningful prognostic marker may have therapeutic relevance.  相似文献   
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In the contemporary clinical setting, a diagnosis of deep vein thrombosis can be established using ultrasound. While different ultrasound modalities, including direct B-mode venous imaging, Doppler, and vein compression, have been employed to diagnose clot, it is the compression technique that has been established as the dominant method. In venographically controlled series, compression ultrasound has demonstrated a 93% sensitivity and 99% specificity for clot detection. These remarkable results have been achieved without the evaluation of calf veins. Recent improvements in instrumentation have permitted the direct visualization of calf veins, and it would seem likely that this will result in even better sensitivity for clot detection.  相似文献   
27.
Chondrosarcoma of the short tubular bones of the hands and feet   总被引:1,自引:0,他引:1  
Objective. To report 12 cases of chondrosarcoma in a rare location, the short tubular bones of the hands and feet, as well as 12 cases of enchondroma in similar locations, emphasizing the radiologic and histopathologic features. Design and patients. All relevant cases that had both histologic slides and radiographs available were taken from the files of one orthopedic referral hospital and the personal files of one of the authors. A similar number of enchondroma cases was selected at random from the files. Results and conclusions. One malignancy arose in a background of enchondromatosis, with all the others being solitary lesions. A pathologic diagnosis of malignancy is often difficult in the absence of radiologic signs of malignancy (cortical destruction with or without soft tissue extension). However, three cases were unusual in that the initial radiograph demonstrated a benign appearance. Another group of three malignancies was surprisingly indolent biologically. The treatment of choice is ray resection (or more limited amputation in a lesion of the middle or distal phalanx).  相似文献   
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Background  

Although the application of damage control surgery for trauma has been widely reported and defined, similar approach in non-trauma patients has not been well detailed.  相似文献   
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Lymphocytic colitis (LC) and collagenous colitis (CC) are diseases characterized by the presence of marked intraepithelial lymphocytosis. Both of these disorders affect primarily the colon. However, involvement of the distal small intestine has not been systematically studied. The purpose of this study was to evaluate the type and degree of intraepithelial lymphocytosis in the terminal ileum of patients with LC or CC. Terminal ileal mucosal biopsies from 22 patients with LC (male/female ratio 0.22, mean age 47 years) and 23 with CC (male/female ratio 0.43, mean age 54 years) were evaluated for the number of intraepithelial lymphocytes (IEL) per 100 epithelial cells (EC) both in the villi and crypts. The results were compared with 30 patients with inflammatory bowel disease (16 with Crohn's disease [CD], 14 with ulcerative colitis [UC]) and 24 patients (male/female ratio 0.33, mean age 44 years) without colonic pathology as normal controls. None of the patients had celiac sprue. Paired terminal ileum and colonic mucosal biopsies from 6 patients with LC, 4 with CC, 5 with CD, 5 with UC, and 10 normal controls were also immunohistochemically stained with monoclonal antibodies to CD3, CD8, CD20, and a class II MHC antigen (LN3-HLA-DR). In the villi the IEL count/100 EC was 11.8 +/- 1.8 in LC and 10.3 +/- 1.9 in CC (p = 0.3). These values were both significantly higher than in CD (2.8 +/- 0.4, p <0.001), UC (3.1 +/- 0.4, p <0.001), or normal controls (2.2 +/- 0.2, p <0.001). In the crypts the IEL count was 3.8 +/- 0.5 in LC and 3.2 +/- 0.5 in CC (p = 0.3). These values were also significantly higher than in CD (2.3 +/- 0.4, p = 0.02), UC (2.1 +/- 0.3, p = 0.02), or normal controls (1.5 +/- 0.2, p <0.001). The presence of >5 IELs/100 EC in terminal ileum biopsies was highly specific for LC and CC (specificity 98%, sensitivity 73% and 56% for LC and CC, respectively). The IEL phenotype was similar in all groups of patients and in the ileum and colon of individual patients. Intraepithelial lymphocytes were CD3+, CD8+, CD20-, and LN3-HLA-DR-, indicative of a suppressor T-cell phenotype. Intraepithelial lymphocytosis occurs in the terminal ileum in patients with LC or CC and may be helpful in diagnosing these conditions and distinguishing LC or CC from CD or UC in diagnostically difficult cases. The results suggest that the terminal ileum may be involved by a similar pathogenic process as the colon in LC and CC.  相似文献   
30.
Wood  GS; Garcia  CF; Dorfman  RF; Warnke  RA 《Blood》1985,66(5):1092-1097
Follicle lysis is a characteristic alteration of B cell follicles described recently in lymph node biopsies from homosexual men. It consists of disruption of germinal centers by aggregates of small mature lymphocytes variably associated with erythrocyte extravasation. We studied the immunohistology of follicle lysis identified in lymph node biopsies from 11 homosexual men. The results indicate that follicle lysis has two principal immunohistologic features: (1) intrafollicular aggregates of small lymphocytes predominantly of polytypic mantle B cell phenotype (T015+/Leu-8+/mu+/delta+/k+ or lambda+), and (2) disruption of the normal, unified follicular meshwork of R4/23+ dendritic reticulum cells by these B cell aggregates. These structural alterations may affect the functional integrity of the germinal center as it pertains to the abnormal B cell effector function and the increased prevalence of B cell lymphoma recently documented in the acquired immunodeficiency syndrome and related disorders. Because dendritic reticulum cells weakly express the Leu-3 (T4) antigen, which is known to be an essential component of the receptor for human T- lymphotropic virus type III/lymphadenopathy-associated virus (HTLV- III/LAV) retrovirus infection, it is possible that retroviral infection of dendritic reticulum cells may play a role in the pathogenesis of follicle lysis.  相似文献   
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