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European Radiology - The strongest adverse prognostic factor in myxoid/round cell liposarcomas (MRC-LPS) is the presence of a round cell component above 5% within the tumor bulk. Its identification...  相似文献   
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Pilomatrixoma are neoplasms of the hair cortical cells. They are most common during the first two decades of life and, usually, involve the head, neck, and upper extremities. These tumors may be encountered during aspiration biopsy of subcutaneous masses, and are, occasionally, confused with other neoplasms, particularly squamous cell carcinomas and epidermal inclusion cysts. The cytologic features of three such neoplasms are presented, and the characteristics that differentiate them from other benign and malignant lesions of the skin are discussed. The presence of two cell populations, the anucleated shadow cells and the basaloid cells, which lack nuclear features of malignancy, is fairly specific for pilomatrixoma. In addition, the specimens obtained from aspiration may be misinterpreted as originating from a hyperplastic lymph node in view of the intense chronic inflammatory and foreign body reaction seen in the background. Calcific deposits that lack lamellations, unlike psammoma bodies, help in establishing the definitive diagnosis of these benign neoplasms.  相似文献   
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Thank you for forwarding the letter of the distinguished colleagues,Andre Scheen and Luc Van Gaal, and the opportunity  相似文献   
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The present work tries to establish the antioxidant capacity of the peripheral nervous tissue of the rat, in terms of the enzymatic activities present in this tissue that either prevent the formation of activated species as the semiquinone radical (DT-diaphorase), protect against activated oxygen species (superoxide dismutase, glutathione peroxidase), conjugate natural toxic products or xenobiotics (glutathione S-transferases, especially the activity conjugating 4-hydroxy-nonenal), or complete the glutathione system metabolism (glutathione disulfide reductase, γ-glutamyl transpeptidase). All the activities studied are lower in this tissue than they are in liver, except for γ-glutamyl transpeptidase. The relevance of the results obtained and its possible relationship with different neuropathies is discussed. It is concluded that the peripheral nervous tissue is by far less protected than the liver against oxidative damage.  相似文献   
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On September 6, 2001, Professor Fernando Valderrabano (Hospital Gregorio Mara?on, Madrid) died at the age of 59 years. He was a leading figure in Spanish nephrology, a full professor of Medicine/Nephrology at the University Complutense of Madrid, and an outstanding scientist who published more than 300 articles in medical journals. He was a very intelligent and cultured person, and a man of great style who enjoyed a wide range of hobbies and interests in addition to his medical work. All his colleagues and friends mourn his passing.  相似文献   
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The use of directional coronary atherectomy (DCA) in current practice has been limited. The SilverHawk System is a newly developed plaque excision device that aims to overcome the drawbacks of prior DCA platforms. The device was evaluated in a porcine coronary model and in a series of patients. Procedural variables along with outcomes were reviewed. Quantitative angiography (QCA) was performed and excised tissue fragments were weighed and examined histologically. In porcine cases, pretreatment MLD increased from 0.51 +/- 0.26 to 2.36 +/- 0.59 mm postdebulking and 19.9 +/- 7.6 mg of tissue was retrieved. In human cases, pretreatment MLD increased from 0.8 +/- 0.4 to 2.2 +/- 0.5 mm postdebulking and 15.2 +/- 7.8 mg of tissue was retrieved without complications. These data show that the SilverHawk System may offer significant utility in treating a wide variety of complex coronary lesions.  相似文献   
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