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11.
Neuroimaging in Pineal Tumors   总被引:4,自引:0,他引:4  
F Reis  MD  AV Faria  MD  PhD  VA Zanardi  MD  PhD  JR Menezes  MD  F Cendes  MD  PhD  LS Queiroz  MD  PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread.  相似文献   
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The authors extracted 11 case files of patients undergoing radical prostatectomy following MRI studies from a series of 192 MRI examinations of the prostate with histological confirmation of the diagnosis. This series is part of a prospective study in which MRI was always interpreted prior to histological results. The diagnosis of prostatic cancer was confirmed in 9 cases on the basis of a hyposignal on T2-weighted scans. In 4 cases, extracapsular spread of the tumour was demonstrated by MRI and was confirmed at surgery. In the cases in which the cancer was visible on MRI, the diagnosis of local spread proved to be accurate. The debate concerning the role of MRI in prostatic disease is not definitively resolved, but this preliminary series indicates the potential and the limitations of this technique.  相似文献   
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Abdominal abnormalities in AIDS: detection at US in a large population   总被引:1,自引:0,他引:1  
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Twenty patients with advanced malignant disease submitted to autologous bone marrow transplantation with marrow either unpurged (10 patients) or purged in vitro with mafosfamide (10 patients) after ablative chemotherapy, received simultaneously autologous peripheral blood stem cells (PBSC) collected during one to three 3 h cytapheresis procedures. The kinetics of the hematological recovery of these patients were compared to those of a group of patients suffering from similar diseases and grafted in the same institution with either unpurged marrow only (14 patients) or purged in vitro with mafosfamide (six patients). The median times to reach 10(9)/l leukocytes, 0.5 x 10(9)/l polymorphs, and 50 x 10(9)/l platelets were reduced by 10, 10, and 13 days, respectively, in patients transfused with both autologous bone marrow and peripheral blood stem cells as compared to those receiving bone marrow only. A reduction in the numbers of days spent in hospital post-transplantation (p less than 0.01), of days of fever greater than 38 degrees C (p = NS), and of platelet (p = 0.07) and of red blood cell transfusions (p less than 0.01) were also observed in the group of patients grafted with bone marrow and PBSC.  相似文献   
16.
Granulomatous prostatitis is an uncommon disease that can prostatic carcinoma on both digital rectal examination and transrectal ultrasound. Four patients who underwent magnetic resonance imaging of the prostate had a histological diagnosis of graanulomatous prostatitis; three of them had recent urinary tract infections. The other patient had an associated midline prostatic cyst and a focus of malignancy. T1-and T2-weighted spin-echo images were obtained in all cases. Peripheral zone lesions of decreased signal intensity, suggestive of carcinoma,were found in all four patients on T2-weighted images. Granulomatous prostatitis should be considered in the differential diagnosis of low signal intensity areas with prostatic magnetic resonance imaging. Correspondence to; P.A. Gevenois  相似文献   
17.
Gastroesophageal reflux disease (GERD) is the most common disease of the upper gastrointestinal tract. With the introduction of proton pump inhibitors medical treatment of GERD has been significantly improved. However, the development of laparoscopic antireflux surgery resulted in an increasing interest of surgeons in this disease. An interactive meeting was organized in order to develop an agreement between gastoenterologists and surgeons regarding therapeutic decisions and this is the main topic of this paper.  相似文献   
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The latissimus dorsi musculocutaneous flap was used to provide chest wall coverage in 40 patients following mastectomy to treat recurrent cancer in irradiated breasts. Although the axillary region had received 50 to 55 grays, the neurovascular pedicle was never jeopardized, thus assuring vascularisation of the flap. In two cases, a small area of skin necrosis in the upper inner border of the flap was observed. Complete healing occurred within weeks. The authors advocate this fast and simple surgical procedure when the quality of the skin and/or the extent of resection prevents primary closure.  相似文献   
20.
2-Nitro-oxaphenalenes are synthetic chemicals which were synthesized in the authors' laboratory. They are the most efficient mutagenic compounds on mammalian cells in culture. They are chemically related to the nitro-naphthofuran family by the displacement of the heterocycle on the naphthalene ring. Since nitro-naphthofurans have a strong mutagenic activity in bacterial tests without metabolic activation and are active in-vivo carcinogens, the purpose of this study was to demonstrate the carcinogenic activity of two 2-nitro-oxaphenalenes. The two compounds were injected s.c. into Wistar rats initially 6-weeks-old. They were dissolved in dimethylsulfoxide (DMSO) at a concentration of 1 mg/ml. A s.c. injection of 0.5 ml containing 0.5 mg of carcinogen was given once a week in the neck of each animal tested. Five control animals were not injected and five animals received 0.5-ml injection of DMSO every week to serve as a control. The animals developed tumors only at the site of injection. The tumors were classified as high grade fibrosarcomas. This experiment demonstrates that: (i) 2-nitro-oxaphenalenes are very active in-vivo carcinogens in rats; (ii) there is a good correlation between the high mutagenic activity especially in mammalian tests and the strong carcinogenicity of the compounds; and (iii) the presence of a 6-methoxy group increases by two-fold the carcinogenic potential.  相似文献   
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