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Neurological disorders, such as seizures, are not infrequently associated with anti-leukemic therapy. It has been hypothesized that a disrupted peptidergic transmission between neurons could be the cellular basis of the neurological dysfunction. Since endogenous opioids have been recently found to alter neuronal function and possess anticonvulsant properties, the cerebrospinal fluid (CSF) immunoreactive beta-endorphin levels in children with Acute Lymphoblastic Leukemia (ALL) during chemotherapy and cranial irradiation have been studied. Twenty-seven children, 2 at low, 20 at medium and 5 with high risk ALL, undergoing prophylactic treatment for meningeal leukemia, entered the study. Sequential lumbar punctures with introduction of MTX combined with oral prednisone therapy were performed; each lumbar puncture sample was collected and assayed for immunoreactive beta-endorphin. All the patients studied showed a biphasic profile of the peptide with the minimum levels reached during the induction (days 14-28) and the maximum levels detected at the end of the intensification chemotherapy (days 49-55). In the 3 groups the beta-endorphin decrease corresponded to the period of prednisone therapy; the increase was concomitant with the suspension of oral glucocorticoids. 3 patients showed tonic-clonic seizures which coincided with the lowest cerebrospinal fluid beta-endorphin levels and, in the follow-up, 13 out of 27 patients displayed EEG abnormalities. From these findings a relationship between cerebrospinal fluid beta-endorphin concentrations and neuronal excitability in patients with ALL can be suggested. It is also evidenced that oral glucocorticoid therapy has profound inhibitory effects on central beta-endorphin levels.  相似文献   
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1-溴-2-甲氧基萘与0-对在苯磺酰乳酸乙酯(1)在无水氯化铝催化下化Friedel-Crafts反应,还原脱溴直接合成dl-1a萘普生(3),以上反应均在“一锅”内完成,收率达95。  相似文献   
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适当使用时,LABAs利大于弊,可继续用于治疗哮喘。FDA建议仅用于哮喘控制药物如吸入性皮质激素不能有效缓解病情的患者。  相似文献   
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Different reconstruction techniques of the anterior and middle skull base as consequence of a defect after surgical treatment of neoplastic pathologies are described in the literature. The aim of the present study is to present our experience regarding the use of microvascular free flaps for reconstruction of the anterior or middle skull base after large defects caused by removal of malignant neoplasms. From 2000 to 2004, in the Department of Maxillo-Facial Surgery of the University of Rome "La Sapienza" and "Tor Vergata," 13 surgical procedures for reconstruction of anterior and middle skull base defects by free flaps were performed in 11 patients. Data on patient demographics, histopathology, location and size of defect, type of reconstruction, and postoperative complications were obtained from medical record charts. A safe soft tissue closure of the intracranial space was achieved in all patients. Defect repair was accomplished by revascularized transfer of rectus abdominis flaps in seven cases, latissimus dorsi muscle flaps in two patients, radial forearm flap in one case, and fibula flap in one case. There were two total flap losses; the secondary defect repair was accomplished in both cases by revascularized transfer of latissimus dorsi muscle flap. No donor site complications were observed in all the flaps. The mean operation time was 85 hours; patients were hospitalized for a mean period of 14 days. The method of choice for the reconstruction of anterior or middle skull base defect should be based upon careful evaluation of the single case and, particularly, the localization and entity of the residual defect. For defects that require large amounts of soft tissue, the latissimus dorsi free flap and the rectus abdominis free flap are the best appropriate choices for reconstructive procedures for anterior and middle skull base tumors.  相似文献   
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