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Summary 4 -Deoxydoxorubicin was given to 15 patients with drug-resistant pediatric malignant solid tumors with the objectives of determining the maximum tolerated dosage and dose-limiting toxicity. Maximum tolerated dosage was 36 mg/m2 given IV once every 3 weeks. Dose limiting toxicity was myelosuppression, which was severe and prolonged. Therapeutic benefits were not observed for these patients.  相似文献   
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Recently, in-vitro maturation (IVM) of immature human oocytes recovered from non-stimulated follicles has been applied in the treatment of infertility. However, in previous reports, very few embryos cultured in conventional medium have reached the expanded blastocyst stage following in-vitro maturation and fertilization (IVM/IVF). The objective of this study was to investigate whether the developmental competence of human embryos following IVM/IVF could be enhanced by the use of a human ampullary cell co-culture system. Immature human oocytes were aspirated from small follicles at Caesarean section and then cultured in medium containing human menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes were randomly cultured either in conventional culture medium alone or in the co-culture system. Of 48 embryos cultured in conventional medium alone, all arrested at the 2-16- cell stage on day 3 after insemination. Of 46 embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at the 2-16-cell stage. Six embryos (13%) developed to the morula stage. Fourteen embryos (30.4%) developed to expanded blastocysts and two blastocysts were hatching on day 7 after insemination. We conclude that co-culture significantly enhances the development of blastocysts in embryos resulting from IVM/IVF.   相似文献   
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The utilization of fibrin sealants to augment hemostasis, seal tissues, and facilitate targeted delivery of drugs is increasing. In 1985, a hospital-based program was established to provide autologous and allogeneic cryoprecipitate that serves as a fibrin sealant when combined with bovine thrombin. To date, more than 4,000 patients have been treated with this product at our institution, with an efficacy rate greater than 90%. Collaboration among surgical services and the blood bank fostered multispecialty expertise with this product that led, in 1997, to the establishment of the University of Virginia Tissue Adhesive Center. The Tissue Adhesive Center is a multidisciplinary center whose physician director and nursing and administrative support staff facilitate basic research, laboratory investigation, and preclinical and clinical trials with collaborators throughout the university. The Tissue Adhesive Center also provides educational programs and clinical consultation, and tracks and participates in peer review of sealant use. The licensure of a commercially produced, virally inactivated, pooled-plasma fibrin sealant in May 1998 provided an alternative source of adhesive. Utilization of the commercial product surpassed use of the blood bank product in April 1999. At present, use of the commercial product is approximately 3 times that of the blood bank-produced sealant. This report reviews the clinical uses of fibrin sealant, its regulatory history, the production of fibrin sealants, the evolution of a blood bank fibrin sealant program, the development of the Tissue Adhesive Center, and the utilization of commercial and blood bank-produced sealant at our university hospital.  相似文献   
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Total nucleic acids prepared from a number of murine retroviruses have been shown to contain virus-specific DNA in addition to genomic RNA. This virus-specific DNA has been shown to be at least partially double stranded and to be present within the virus core particle. The DNA isolated from the virus is greatly enriched in virus-specific DNA relative to that from virus infected cells.  相似文献   
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The sister chromatid exchange (SCE) incidence and growth kinetics have been studied by means of an in vitro bromodeoxyuridine (BrdU) chromosome labeling method in the bone marrow cells of 17 acute myeloblastic leukemia (AML) patients with only diploid cells at diagnosis, remission, and relapse of the disease. At diagnosis, the cells tended to exhibit a low SCE frequency as compared to that during remission. An increased SCE frequency was observed after chemotherapy during remission or relapse. At diagnosis and relapse, when leukemic blast cells predominated in the marrow, they were characterized by the predominance of cells that had undergone only one cell cycle after BrdU exposure. In contrast, the marrow cells during remission tended to resemble the control pattern of growth kinetics, with a predominance of cells undergoing second and third cell cycles in the presence of BrdU. These results suggest that the growth rate of leukemic and nonleukemic cells is different, and that chemotherapy can cause an increased SCE frequency in the marrow cells of AML patients irrespective of the state of the disease.  相似文献   
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Following its benchmark discovery, nitric oxide (NO) is nowknown to play important functional roles in a variety of physiologicalsystems. Within the vasculature, NO induces vasodilation, inhibitsplatelet aggregation, prevents neutrophil/platelet adhesionto endothelial cells, inhibits smooth muscle cell proliferationand migration, regulates programmed cell death (apoptosis) andmaintains endothelial cell barrier function. NO generated byneurons acts as a neurotransmitter, whereas NO generated bymacrophages in response to invading microbes acts as an antimicrobialagent. Because neurons, blood vessels and cells of the immunesystem are integral parts of the reproductive organs, and inview of the important functional role that NO plays in thosesystems, it is likely that NO is an important regulator of thebiology and physiology of the reproductive system. Indeed, inthe past 10 years, NO has established itself as a polyvalentmolecule which plays a decisive role in regulating multiplefunctions within the female as well as the male reproductivesystem. This review provides an overview of the role of NO invarious reproductive organs under physiological and pathologicalconditions.  相似文献   
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