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BACKGROUND: Although transthoracic needle biopsy (TNB) has been the preferred method for the diagnosis of anterior mediastinal masses, it has inherent limitations in accuracy. In particular, lymphoma and thymoma are diagnosed less reliably using needle biopsy. Videothoracoscopy has been advocated as an alternative method for diagnosis. Our goal was to assess the usefulness of extended cervical mediastinoscopy (ECM) in the diagnosis of anterior mediastinal masses. METHODS: The ECM technique was performed in 9 patients in whom TNB and Tru-cut biopsies had been inefficient for histologic diagnosis. All lesions were in the anterior mediastinum. Extended cervical mediastinoscopy was carried out using the same incision as in a standard cervical mediastinoscopy and dissection was performed behind the sternum as previously published. Mean operative time was 50 minutes (range 40 to 70 minutes) and mean hospital stay was 8 hours (range 5 to 36 hours). RESULTS: Diagnosis of lymphoma in 4 cases, thymoma in 3 cases, and thymic hyperplasia in 2 cases were obtained by ECM. In 1 of 2 patients with suspected thymoma who underwent resectional surgical procedures, final histologic diagnosis was non-small cell lung carcinoma. There was no surgical mortality or intraoperative complication. One patient had minimal pneumothorax requiring no intervention. CONCLUSIONS: We conclude that ECM in the diagnosis of anterior mediastinal masses is technically feasible and provides an alternative to the conventional approaches in patients with paraaortic or aortopulmonary masses. 相似文献
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Undar A Eichstaedt HC Clubb FJ Fung M Lu M Bigley JE Vaughn WK Fraser CD 《The Annals of thoracic surgery》2002,74(2):355-62; discussion 362
BACKGROUND: Adverse outcomes after cardiopulmonary bypass (CPB) are often related to systemic inflammation triggered by complement and leukocyte activation. To determine how inhibition of the alternative complement pathway affects systemic inflammation and tissue injury, we studied a novel monoclonal antibody (Mab), anti-human factor D murine Mab 166-32, in baboons. METHODS: Fourteen baboons (mean weight, 15 kg) underwent hypothermic CPB. The treatment group (n = 7) received a single injection of anti-factor D Mab 166-32 (5 mg/kg), and the control group (n = 7) was given saline solution. After initiation of CPB, all animals were subjected to 20 minutes of core cooling (rectal temperature, 27 degrees C), followed by 60 minutes of aortic cross-clamping, 25 minutes of rewarming, and 30 minutes of normothermic CPB. Blood samples were collected before CPB, during CPB, and 1, 2, 3, 6, and 18 hours after CPB. To measure neutrophil and monocyte activation, we performed flow cytometry for CD11b expression, ELISA for complement activation (Bb, C3a, C4d, and sC5b-9) and interleukin-6 (IL-6) production, and tissue injury studies for creatine kinase MB isoenzymes (CK-MB), creatine kinase (CK), and lactic dehydrogenase (LDH) levels. RESULTS: Anti-factor D Mab almost completely inhibited plasma Bb, C3a, and sC5b-9 production during CPB (P < .001). CD11b expression on neutrophils (129 +/- 5% vs. 210 +/- 42%; P = .0006) and on monocytes (139 +/- 14% vs. 245 +/- 43%; P = .0002) was also lower in the treatment group during CPB. The treated animals had a significantly smaller increase in plasma IL-6 concentrations than did the control animals (71 +/- 27 pg/mL vs. 104 +/- 54 pg/mL; P = .0002). CK-MB levels were also lower in the treatment group 6 hours after the end of CPB (204 +/- 30 vs. 335 +/- 59 IU/L; P = .003) and 18 hours after the end of CPB (P < .05). Creatine kinase levels (6 and 18 hours after the end of CPB) and LDH levels (3 and 6 hours after the end of CPB) showed patterns similar to those of CK-MB (P < .05). CONCLUSIONS: The alternative complement pathway plays a major role in systemic inflammation during CPB. Inhibition of complement activation via the alternative pathway by anti-factor D Mab 166-32 significantly reduces leukocyte activation and tissue injury in our baboon model. 相似文献
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Bilateral elastofibroma dorsi 总被引:1,自引:0,他引:1
Elastofibroma dorsi was diagnosed in a 48-year-old woman with bilateral subscapular tumor masses diagnosed asynchronously in an interval of 4 months in spite of presence of another lesion at first admittance. She underwent subsequent resections of the lesions. They were diagnosed as elastofibroma. Reevaluation of the initial computerized tomography of thorax indicated an omitted small lesion with a 2-cm diameter and 25.2-day doubling time. Although the real neoplastic nature of elastofibroma is unknown, bilateral presence of the masses with different sizes and relatively short doubling times of the lesions must be kept in mind. 相似文献
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Yerebakan O Uğuz A Keser I Lüleci G Ciftçioğlu MA Başaran E Alpsoy E 《Pediatric dermatology》2002,19(4):345-348
Netherton syndrome is a rare genodermatosis comprised of anichthyosiform dermatitis, hair shaft defects, and atopic features. Other problems associated with Netherton syndrome are delayed growth and development, immune abnormalities, recurrent infections, and intermittent aminoaciduria. We describe an 18-month-old girl with Netherton syndrome who had idiopathic congenital hemihypertrophy on her right side with contralateral benign nephromegaly in addition to the characteristic clinical signs of the syndrome. To our knowledge, this is the first case of Netherton syndrome associated with idiopathic congenital hemihypertrophy to be reported. 相似文献
56.
Tezcan FA Findley WM Crane BR Ross SA Lyubovitsky JG Gray HB Winkler JR 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(13):8626-8630
Replacement of iron with cobalt(III) selectively introduces a deep trap in the folding-energy landscape of the heme protein cytochrome c. Remarkably, neither the protein structure nor the folding thermodynamics is perturbed by this metal-ion substitution, as shown by data from spectroscopic and x-ray diffraction experiments. Through kinetics measurements, we have found parallel folding pathways involving several different misligated Co(III) species, and, as these folding intermediates persist for several hours under certain conditions, we have been able to elucidate fully their spectroscopic properties. The results, along with an analysis of the fluorescence energy-transfer kinetics during refolding, show that rapidly equilibrating populations of compact and extended polypeptide conformations are present until all molecules have reached the native structure. These measurements provide direct evidence that collapsed denatured structures are not substantially more stable than extended conformations of cytochrome c. 相似文献
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Miliary tuberculosis is caused by the hematogenous spread of Mycobacterium tuberculosis and consists of 1.5% of all tuberculosis cases. It is seen mostly in infants because of the immature immune system, and central nervous system CNS involvement is not rare. Tuberculomas are rarely seen in the localized form of CNS tuberculosis, and only 4% are localized in the brain stem. We report a 4.5-month-old infant who deteriorated during follow-up with the diagnosis of cytomegalovirus pneumonia, and afterwards received the diagnosis of miliary tuberculosis. Although the baby had no neurologic abnormality and cerebrospinal fluid findings were normal, cranial MRI revealed contrast enhanced nodular lesions in pons, cerebellum, and right parietal region. The case is presented to intensify the importance of CNS investigation even if the patient with miliary tuberculosis has no neurologic finding. 相似文献