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991.
<正>To the Editor:Hepatocellular adenomas(HCAs)consist of benign liver tumors favored by the use of oral contraceptives,which preferentially occur in women.~([1,2]) They expose to the risk of hemorrhage(20%of cases)and more rarely,to the risk of malignant transformation(4%-10%of cases).~([3,4])Multiple HCAs,which are defined by the presence of 10 or more  相似文献   
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Background and purpose Little is known about the long-term outcome of cemented metal-on-metal hip arthroplasties. We evaluated a consecutive series of metal-on-metal polyethylene-backed cemented hip arthroplasties implanted in patients under 60 years of age.Methods 109 patients (134 joint replacements) were followed prospectively for mean 9 (7–11) years. The evaluation included clinical score, radiographic assessment, and blood sampling for ion level determination.Results At the final review, 12 hips had been revised, mainly because of aseptic loosening of the socket. Using revision for aseptic loosening as the endpoint, the survival rate at 9 years was 91% for the cup and 99% for the stem. In addition, 35 hips showed radiolucent lines at the bone-cement interface of the acetabulum and some were associated with osteolysis. The median serum cobalt and chromium levels were relatively constant over time, and were much higher than the detection level throughout the study period. The cobalt level was 1.5 μg/L 1 year after implantation, and 1.44 μg/L 9 years after implantation.Interpretation Revisions for aseptic loosening and radiographic findings in the sockets led us to halt metal-on-metal-backed polyethylene cemented hip arthroplasty procedures. If the rigidity of the cemented socket is a reason for loosening, excessive release of metal ions and particles may be involved. Further investigations are required to confirm this hypothesis and to determine whether subluxation, microseparation, and hypersensitivity also play a role.  相似文献   
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Purpose  

The following hypothesis was tested: the location of the tibial and femoral anterior cruciate ligament (ACL) attachments will differ according to the measurement technique (plain radiographs or CT-scan) in relation to the anatomic frame of reference.  相似文献   
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Several 4,5-bis(dialkylaminoalkyl)-substituted acridines have been prepared starting from acridine and their telomeric G-quadruplex stabilizing properties were evaluated using FRET melting and TRAP (Telomerase Repeat Amplification Protocol Assay) experiments.  相似文献   
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Despite the near concurrent publication by influential scientific organizations, there are important differences in interpretation of the evidence base and the conclusions derived from the recent Osteoarthritis Research Society International (OARSI) guidelines for the management of knee osteoarthritis, the American College of Rheumatology (ACR) guidelines (concerning also hip and hand osteoarthritis) and the algorithm recommendations by the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis (ESCEO). This is particularly evident for the drug class of symptomatic slow-acting drugs in osteoarthritis. In this paper, we highlight these differences and try to understand where they derive from, proposing an evidence-based interpretation.  相似文献   
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Redefining parapharyngeal space infections   总被引:4,自引:0,他引:4  
OBJECTIVES: Our intent was to review the clinical signs, computed tomography (CT) scans, treatment, and outcome of parapharyngeal space infections (PPIs), and to define 2 types of infections of the parapharyngeal space (PPS) according to the location of the infectious process. METHODS: We performed a retrospective analysis of patients hospitalized in a tertiary university hospital with a diagnosis of PPI, abscess, or deep neck abscess between 1988 and 2004. Files and CT scans were reviewed after classification into 2 groups: 1) infection located in the posterior part of the PPS (PostPPI); and 2) infection located in the anterior part of the PPS (AntPPI). RESULTS: Twenty-two patients had a PostPPI; their ages ranged from 10 months to 24 years. Five patients underwent surgical drainage, and 17 others were treated solely with intravenous antibiotic therapy. No pus was found during surgery in 2 patients. The average time of hospitalization was 10 days. Only 1 complication (aspiration pneumonia) was observed. Seven patients had an AntPPI; their ages ranged from 1.5 years to 65 years. All patients underwent surgical drainage, and pus was detected in all cases. The average time of hospitalization was 35 days. Complications (septic shock, respiratory arrest, mediastinitis, pleural empyema, pericarditis) were observed in 4 patients. CONCLUSIONS: The term "parapharyngeal abscess" was assigned long before the CT scan era, and was based on physical examination and plain film radiology. In essence, the entity PPS "abscess" or "infection" is composed of 2 different disorders. Infection located in the posterior part of the PPS with no invasion into the parapharyngeal fat and with no extension into other cervical spaces except the adjacent retropharyngeal space may be termed posterior parapharyngeal infection or parapharyngeal lymphadenitis. This is a relatively benign condition, and nonsurgical treatment should be considered. Infection involving the parapharyngeal fat may be termed parapharyngeal abscess or deep neck abscess. Diffusion into the mediastinum and other severe complications are frequent. Urgent surgical drainage is therefore mandatory.  相似文献   
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