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81.
Alexandros E. Beris M.D. Marios G. Lykissas M.D. Alexandros Payatakes M.D. Vasileios A. Kontogeorgakos M.D. Alexandros Mavrodontidis M.D. Anastasios V. Korompilias M.D. 《Microsurgery》2009,29(3):240-243
We present a case of a 34‐year‐old white female patient who, 13 years ago, sustained a pathological intracapsular femoral neck fracture on a pre‐existing aneurysmal bone cyst. Three months later radiographic and magnetic resonance imaging evaluation revealed both femoral neck fracture and stage IV osteonecrosis of the femoral head according to Steinberg classification system. Management was accomplished with combined free vascularized fibular grafting and internal osteosynthesis with a 130° blade plate. Union was achieved in 7 months. Progression of osteonecrosis was arrested. Hip salvage and a satisfactory subjective and clinical outcome were achieved. At the last follow‐up, 13 years postoperatively, the patient had satisfactory functional outcome. © 2008 Wiley‐Liss, Inc. Microsurgery, 2009. 相似文献
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83.
BACKGROUND: Recent evidence suggests that the neural correlates of reversal learning are localised to the orbitofrontal cortex whereas studies on the contribution of the medial prefrontal cortex to this capacity have produced equivocal results. This study examines the behavioural effects of selective lesions centred on orbitofrontal, infralimbic and prelimbic cortex on serial spatial reversal learning in the rat. METHODS: Rats were trained on a novel instrumental two-lever spatial discrimination and reversal learning task, measuring both 'cognitive flexibility' and constituent processes including response inhibition. Both levers were presented, only one of which was reinforced. The rat was required to respond on the reinforced lever under a fixed ratio 3 schedule of reinforcement. Following attainment of criterion, a series of reversals was presented. RESULTS: Bilateral excitotoxic lesions of the orbitofrontal cortex did not affect retention of a preoperatively acquired spatial discrimination but did impair reversal learning. This deficit manifested as increased perseverative responding on the previously correct lever. Although impairments were evident during reversal 1, OFC-lesioned animals performed significantly better than controls on reversal 2. There were no significant effects of infralimbic and prelimbic lesions on the retention of a spatial discrimination or reversal learning. CONCLUSIONS: These results indicate that the orbitofrontal cortex is critical for flexible responding in serial spatial reversal learning. The present findings may be relevant to deficits in reversal learning and response inhibition in such neuropsychiatric disorders as obsessive-compulsive disorder. 相似文献
84.
Effrossyni Gkrania-Klotsas MD MPH Fiona J. Cooke MD PhD Vasileios Zochios MD Nikoletta Lofitou MD 《Journal of travel medicine》2009,16(1):57-59
Fever, caused by Salmonella typhi , is the cause of significant morbidity worldwide. Extraintestinal manifestations of typhoid fever can confuse clinicians in Western countries, delaying diagnosis. We present an extraordinary case of typhoid fever, manifesting as hand cyanosis as well as abducens nerve paresis, all of which promptly resolved with antibiotics. 相似文献
85.
Chouliaras V Ristanis S Moraiti C Stergiou N Georgoulis AD 《The American journal of sports medicine》2007,35(2):189-196
BACKGROUND: The 2 most frequently used autografts for anterior cruciate ligament reconstruction are the bone-patellar tendon-bone and the quadrupled hamstrings tendon. HYPOTHESIS: Hamstring tendon graft is superior to patellar tendon graft in restoring tibial rotation during highly demanding activities because of its superiority in strength and linear stiffness and because it is closer morphologically to the anatomy of the natural anterior cruciate ligament. STUDY DESIGN: Case control study; Level of evidence, 3. METHODS: Eleven patients with patellar tendon graft anterior cruciate ligament reconstruction, 11 patients with hamstring tendon graft anterior cruciate ligament reconstruction, and 11 controls were assessed. Kinematic data were collected (50 Hz) with a 6-camera optoelectronic system while the subjects descended stairs and, immediately after, pivoted on their landing leg. The dependent variable examined was the tibial internal-external rotation during pivoting. All patients in both groups were also assessed clinically and with the use of a KT-1000 arthrometer to evaluate anterior tibial translation. RESULTS: The results demonstrated that reconstructions with either graft successfully restored anterior tibial translation. However, both anterior cruciate ligament reconstruction groups had significantly increased tibial rotation when compared with the controls, whereas no differences were found between the 2 reconstructed groups. CONCLUSION: The 2 most frequently used autografts for anterior cruciate ligament reconstruction cannot restore tibial rotation to normal levels. CLINICAL RELEVANCE: New surgical techniques are needed that can better approximate the actual anatomy and function of the anterior cruciate ligament. 相似文献
86.
Elias J Semelka RC Altun E Tsurusaki M Pamuklar E Zapparoli M Voultsinos V Armao DM Rubinas T 《Journal of magnetic resonance imaging : JMRI》2007,26(6):1556-1563
PURPOSE: To assess the frequency of occurrence of poorly-marginated and focally-defined pancreatic ductal adenocarcinoma by MRI and to determine whether these appearances correlate with clinical features and histopathological grade. MATERIALS AND METHODS: Institutional review board with waiver of informed consent was obtained for this HIPAA compliant study. A total of 33 patients (16 female, 17 male, mean age = 63.5 +/- 12.8, ranging from 41 to 80 years) with histopathologically-proven pancreatic ductal adenocarcinoma who underwent MR examination between August 2000 and February 2005 were retrospectively evaluated. Clinical data and histopathological tumoral grade were obtained from clinical charts; nine of 33 patients were excluded of the histopathological evaluation since their diagnosis was performed by fine needle aspiration biopsy and it was not possible to obtain the histopathological grade. Two radiologists reviewed all cases independently to identify whether cancers were poorly-marginated or focally-defined. Agreement between radiologists was assessed using the kappa coefficient. The overall correlation between imaging findings, clinical features, and histopathological grade was assessed with contingency tables using the Fisher's exact test. RESULTS: Of the 33 patients, nine (27.2%) were classified as poorly-marginated and 24 (72.8%) as focally-defined. Agreement between the two reviewers was excellent (k = 0.92, 95% confidence interval (CI) = 0.78-1.0). Poorly-marginated cancers exhibited well- to moderately-differentiated histopathology in 71.4% of cases, while focally-defined cancers had well- to moderately-differentiated histopathology in 17.6% of cases, P = 0.02. CONCLUSION: A poorly-marginated appearance of pancreatic ductal carcinoma on MRI is not uncommon. These cancers exhibited statistically significant moderate- to well-differentiated histopathology compared to focally-defined cancers. 相似文献
87.
Pili R H?ggman M Stadler WM Gingrich JR Assikis VJ Bj?rk A Nordle O Forsberg G Carducci MA Armstrong AJ 《Journal of clinical oncology》2011,29(30):4022-4028
88.
Primary pancreatic cystic neoplasms have been recognized increasingly during the two recent decades and include mainly serous cystic neoplasms, mucinous cystic neoplasms, and intraductal papillary mucinous neoplasms. Serous cystic neoplasms represent about 30% of all cystic neoplasms of the pancreas and are characterized by their microcystic appearance (on imaging, macroscopically, and microscopically) and their benign biologic behavior. Modern diagnostic methodology allows the preoperative diagnosis with an acceptable accuracy. Currently, indications for resection of serous cystic neoplasms of the pancreas include the presence of symptoms, size > 4 cm (because these ‘large’ neoplasms have a more rapid growth rate and probably will soon become symptomatic), and any uncertainty about the diagnosis of a serous versus a mucinous cystic neoplasm. Resection should also be considered for lesions in the body/tail of the pancreas. Conservative treatment is a reasonable option in selected patients (for example in the presence of small, asymptomatic lesions in the pancreatic head, especially in the frail or elderly patient). 相似文献
89.
Dimos Karangelis Georgios I Tagarakis Marios Daskalopoulos Georgios Skoumis Nicholaos Desimonas Vasileios Saleptsis Theocharis Koufakis Athanasios Drakos Dimitrios Papadopoulos Nikolaos B Tsilimingas 《Journal of cardiothoracic surgery》2010,5(1):61
Objective
The aim of the present study was to evaluate the efficacy of autologous blood pleurodesis in the management of persistent air leak in spontaneous pneumothorax. 相似文献90.