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41.
Although somatic mutations of p53 are the most common genetic changes observed to date, the frequency of germline p53 mutations is found to be very low in sporadic malignant tumors. It has been postulated that de novo germline p53 mutations may occur in a substantial population of patients in pediatric age group, who die of their disease and do not propagate the mutation. To determine the frequency and type of p53 germline mutations in pediatric patients, we screened 65 children who were consecutively admitted with primary malignant solid tumors.  相似文献   
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Summary Cytocidal activity of a drug is dependent on both drug dosage and duration of exposure. In contrast to the conventional 6-h infusion and in an attempt to improve its efficacy, the high-dose methotrexate therapeutic regimen was given over a 24-h period with 10% of the dose administered in the first hour. Citrovorum factor was initiated at hour 24 and continued for 72 h. Treatment was administered every 2–3 weeks. 57 infusions were performed in twelve patients aged 7–20 years (six with osteogenic sarcoma and six with acute lymphoblastic leukemia). Determinations of serum methotrexate levels revealed that the levels were dependent on the dose. Levels assayed at 24 h revealed the following results: 4.4±1.4x10-5 molar with 4.5 g/m2, 2.04±0.34x10-4 molar with 7.5 g/m2 and 4.59±0.80x10-4 molar with 12.5 g/m2. Major toxicity was myelosuppression in 12 of 57 patients. There were no responses. The study demonstrates that 24-h infusions of high-dose methotrexate can be tolerated every 2–3 weeks in patients without bone marrow involvement and levels of at least 10-4 molar can be maintained during the infusion.Supported in part by a research grant (CA06516) from the National Cancer Institute and by a grant (RR-05526) from the Division of Research Facilities and Resources, National Institute of HealthCharles A. Janeway Scholar and American Cancer Society Fellow  相似文献   
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A prospective observational study of 101 women having breast surgery under general anaesthesia was performed to assess the extent of postoperative nausea and vomiting in this group of women. The overall rate of postoperative nausea and vomiting was high, 56% and 41%, respectively, and was significantly associated with length of surgical procedure and morphine use. Techniques to reduce morphine requirement should be evaluated to try and reduce this cause of morbidity.  相似文献   
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PURPOSE: The idiotype (Id) of the immunoglobulin on a given B-cell malignancy is a clonal marker that can serve as a tumor-specific antigen. We developed a novel vaccine formulation by incorporating Id protein with liposomal lymphokine that was more potent than a prototype, carrier-conjugated Id protein vaccine in preclinical studies. In the present study, we evaluated the safety and immunogenicity of this vaccine in follicular lymphoma patients. EXPERIMENTAL DESIGN: Ten patients with advanced-stage follicular lymphoma were treated with five doses of this second generation vaccine after chemotherapy-induced clinical remission. All patients were evaluated for cellular and humoral immune responses. RESULTS: Autologous tumor and Id-specific type I cytokine responses were induced by vaccination in 10 and 9 patients, respectively. Antitumor immune responses were mediated by both CD4+ and CD8+ T cells, were human lymphocyte antigen class I and II associated, and persisted 18 months beyond the completion of vaccination. Specific anti-Id antibody responses were detected in four patients. After a median follow-up of 50 months, 6 of the 10 patients remain in continuous first complete remission. CONCLUSIONS: This first clinical report of a liposomal cancer vaccine demonstrates that liposomal delivery is safe, induces sustained tumor-specific CD4+ and CD8+ T-cell responses in lymphoma patients, and may serve as a model for vaccine development against other human cancers and infectious pathogens.  相似文献   
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Langerhans' cell histiocytosis (LCH) of the liver is uncommon. When seen, it is part of multifocal disease and can present as biliary obstruction. We present a case of sclerosing biliary disease with a solitary LCH lesion and no evidence of systemic disease. We postulate that the LCH is a secondary phenomenon, arising against a background of a complex, familial liver disease. This case also raises the possibility that some instances of idiopathic sclerosing cholangitis may follow cryptic LCH of the bile ducts.  相似文献   
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Given the increasing advocacy for the use of inhaled corticosteroids as a treatment of choice for persistent asthma, growing numbers of children are being exposed to the possible growth-suppressing effects of glucocorticoids. Recent evidence strongly suggests that, when consistently administered at moderate doses, inhaled corticosteroids (IC) are capable of slowing growth in children. Whether such growth suppression would persist and ultimately affect final adult height remains unknown. Therapeutic goals which aim for uninterrupted inflammatory disease control rather than periodic symptom control may increase the occurrence of growth failure in children treated with IC. In this article, current information about the mechanisms of growth suppression by glucocorticoids and the effects of IC on growth is reviewed, and recommendations for designing studies to investigate the effects of drugs on growth are presented.  相似文献   
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