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Cerebral venous angiomas: MR imaging   总被引:3,自引:0,他引:3  
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Hydroxyurea (HU) is an oral drug that ameliorates the clinical course of sickle cell anemia by &#175 increasing the levels of fetal hemoglobin and decreasing the adhesion of red cells to endothelium. Although HU has minimal short-term toxicity, few data are available about the long-term safety and the potential risk for carcinogenesis or leukemogenesis. An 8-year-old child with sickle cell / &#103 0- thalassemia who received HU treatment for painful crises is described. Six months after the initiation of the HU treatment he developed Hodgkin's disease, lymphocyte predominance subtype. Chemotherapy induced a complete remission. After discontinuation of chemotherapy the painful crises recurred and bone marrow transplantation was decided at the age of 12 years. Two years after the bone marrow transplantation, the child is in complete remission without painful crises. Although the authors suggest that the development of Hodgkin's disease is a coexisting event, questions arise about the safety of HU treatment in childhood.  相似文献   
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Non-Hodgkin's lymphomas (NHL) were often erroneously diagnosed as other malignancies and treated accordingly. In this study cisplatin combined with vincristine, cyclophosphamide, and Adriamycin was used incidentally as a front-line treatment in seven children with NHL, because the initial histologic diagnosis was that of a sarcoma. After reevaluation three patients had Ki-1 anaplastic large cell lymphoma of T-cell origin, two abdominal B-cell diffuse high-grade NHL, one mediastinal diffuse large B-cell lymphoma, and one B-cell lymphoma in the stomach. They received at least two courses of cisplatin combined regimen and continued with other protocols for NHL. All patients showed an extremely good response from the first course of therapy and the masses vanished completely. They were followed up for a mean time of 29.5 months and are all in complete remission. The data indicate that cisplatin is active against NHL and might be a promising alternative front-line therapy.  相似文献   
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Mechanical ventilation deteriorates previously injured lung, but little is known about its effect on healthy human lung. This work was designed to assess the effect of prolonged mechanical ventilation on bronchoalveolar lavage (BAL) fluid composition of patients without acute lung injury. Twenty-two ventilated patients (tidal volume 8-10 mL x kg(-1), positive end-expiratory pressure 3-5 cmH2O) without lung injury, who did not develop any complication from the respiratory system during the 2-week study period, were studied. They were subjected to three consecutive BALs, the first during 36 h from intubation, the second at the end of the first week of mechanical ventilation and the third at the end of the second week of mechanical ventilation. Total BAL protein increased during mechanical ventilation (148 +/- 62, 381 +/- 288, 353 +/- 215 microg x mL(-1) BAL for the first, second and third BAL, respectively). In contrast, BAL phospholipids decreased (2.7 +/- 1.1, 1.4 +/- 0.6, 1.2 +/- 0.7 microg x mL(-1) BAL, respectively). Large surfactant aggregates were reduced and inflammatory markers, such as platelet activating factor (PAF), PAF-acetylhydrolase and neutrophils, significantly increased after 1 week, but partially remitted after 2 weeks of mechanical ventilation. In summary, this study demonstrates that prolonged mechanical ventilation even of patients without acute lung injury is associated with the presence of inflammatory markers and surfactant alterations.  相似文献   
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The adverse effect of disease and chronic corticosteroid therapy on bone mineral density (BMD) in patients with systemic lupus erythematosus (SLE) has been reported in several studies of Caucasian populations. As the factors controlling bone homeostasis may be different in Asian populations, we measured BMD in 52 pre-menopausal Chinese women (mean age 34.1 +/- 8.0 yr) with SLE (mean disease duration 6.4 +/- 4.5 yr) treated with prednisone (mean daily dose 11.4 +/- 10.8 mg/day). Lumbar spine, hip (total and subregions) and total body BMDs were measured in the SLE patients using dual-energy X-ray absorptiometry (DEXA), and compared with those from healthy controls matched for age, sex and body mass index. Compared to controls, SLE patients were found to have lower BMD (g/cm2) at several sites: the lumbar spine (0.98 vs 0.90, P = 0.001), Ward's triangle (0.72 vs 0.67, P = 0.03), total body (1.04 vs 1.01, P = 0.04) and total hip (0.87 vs 0.82, P = 0.05). There was no correlation between BMD at any region and duration of disease, activity of disease or prednisone therapy (mean daily dose, cumulative dose or treatment duration). When BMDs were compared between controls and SLE patients, subgrouped according to those not on calcium and those arbitrarily receiving calcium supplements (1 g/day), significantly lower BMDs were found in those not on calcium compared to both controls and SLE patients on calcium. BMDs in SLE patients on calcium were not different from those in controls. The low prevalence of osteoporosis in our SLE patients (4-6%) suggests significant loss of BMD in Chinese SLE patients on corticosteroid therapy is less than that reported in Caucasians (12-18%).   相似文献   
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Background As a complement to sentinel node dissection (SLND), we evaluated ultrasound-guided fine-needle aspiration (USFNA) of normal and abnormal axillary nodes in breast cancer patients. We hypothesized that USFNA would be accurate for primary breast tumors larger than 2 cm. Methods We retrospectively reviewed 68 patients who underwent 69 preoperative USFNAs from 2003 to 2005. The results of 65 preoperative USFNA were compared with the results of SLND or axillary node dissection (ALND) for concordance. Four USFNAs were excluded from analysis because of a complete response to neoadjuvant therapy. We evaluated whether primary tumor features (histology, size, grade, vascular invasion, estrogen/progesterone receptor status and Her-2-neu status) predicted concordance of USFNA results and the final lymph node pathology. Results Of 65 axillae analyzed, 39 (60%) were positive, four (6%) were non-diagnostic, and 22 (34%) were negative by USFNA. USFNA had 89% sensitivity, 100% specificity, and 100% positive predictive value (PPV) in patients with palpable or ultrasonographically suspicious nodes. USFNA sensitivity dropped significantly for nonpalpable, ultrasonographically normal nodes (54%), while specificity and PPV remained 100%. None of the primary tumor features predicted concordance of USFNA and SLND/ALND. Conclusions USFNA of axillary nodes has a high specificity and PPV in clinically or radiologically suspicious nodes. Sensitivity of USFNA is low for nodes of normal appearance, but positive USFNA may allow definitive management of the axilla without a SLND. Thus, USFNA of normal appearing nodes might be beneficial in cases where decisions regarding neoadjuvant chemotherapy would be affected by the results.  相似文献   
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