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Structural anomalies of mitotic chromosomes from two tumorigenic cell lines of the German cockroach (Blattella germanica) is described. Aberrations, such as unpairable marker chromosomes, double minutes, di- and tricentrics, ring chromosomes, tri- and quadriradials, and chromosome and chromatid gaps and breaks, were observed in varying proportions. This study reports that the double minute chromosomes (DMs) are associated with insect tumor cells, similar to the findings in both murine and human tumor cells.  相似文献   
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Malignancy in patients with constitutional chromosome abnormality is of interest not only because it permits insights into the relationship between chromosome abnormality and cancer, but also because it provides opportunities to address such questions as the clonality and evolution of tumors. We report Ph1-positive chronic myelogenous leukemia (CML) in a 50-year-old mosaic (45,X/46,XX) Turner syndrome patient whose leukemia was restricted to the monosomic cell line. Our extensive cytogenetic studies of this patient demonstrated that non-leukemic normal cells persisted in the marrow and were able to proliferate during a period of temporary suppression of the leukemic clone following aggressive treatment.  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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Bronchodilator efficacy of metaproterenol sulfate aerosol therapy delivered either by canister or jet nebulizer was compared in 25 patients, 13 with severe asthma and 12 with COPD. Treatment was carried out in double-blind crossover fashion on 2 days and consisted of either metaproterenol sulfate solution 15 mg in 2.3 ml administered from a jet nebulizer or three puffs of metered-dose metaproterenol sulfate (total 1.95 mg) inhaled sequentially. FVC and FEV1 were monitored before and after therapy for 2 hr. In 13 asthmatic patients, FEV1 increased from a baseline mean of 0.83 L to 1.57 L at 2 hr after jet nebulizer therapy and increased from 0.84 L to 1.52 L after canister therapy. In 12 patients with COPD, FEV1 increased from 0.58 L to 0.78 L after jet nebulizer therapy and from 0.57 L to 0.76 L after canister therapy. FVC also increased similarly after each form of therapy. The two types of aerosol therapy were equally effective and were without side effects. Canister therapy has the advantage over jet nebulizer therapy by being convenient and cheaper.  相似文献   
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To more nearly accurately quantitate the dose of pharmacologic agents delivered to human and animal airways via aerosols, we have developed a monodisperse aerosol containing either methacholine or histamine that permits a light scattering device (tyndallometry) to measure accurately the quantity of inspired and expired particles. These aerosols (described in previous studies) are simultaneously tagged with a radioactive label (technetium 99m) to permit the use of external gamma camera imaging. Present work focuses on the development of assay techniques to measure the quantity of methacholine delivered in these aerosols. The lack of specific radioimmune or radioenzyme assays coupled with the cross-reaction of organic contaminants with conventional chemical reagents for measuring methacholine required the development of separative techniques to isolate the methacholine from the organic aerosol contaminants. With aqueous extraction and column separation we have been able to completely isolate the methacholine from these contaminants. This allows the application of standard spectrophotometric assays for methacholine to quantitate the methacholine in the resulting solution. These separative techniques will permit the use of these aerosols in quantitative studies of airway reactivity.  相似文献   
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本文应用HRP和荧光素标记法对大白鼠外侧隔核的传入性神经纤维联系进行了研究。实验结果表明,外侧隔核的传入神经纤维来源于端脑海马的CA_(1-4)区、杏仁皮质核、内嗅区皮质、斜角带核、视前内侧核、视前外侧核;丘脑的室周核和带旁核;底丘脑的Forel's H_2区和未定带;下丘脑的前核、外侧核、后核以及乳头体上核;中脑的腹侧被盖区。  相似文献   
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Growth of diploid cells from breast cancers   总被引:1,自引:0,他引:1  
Cell cultures were derived from normal and cancerous breast tissues and from metastases by methods that selected for relatively adherent epithelial aggregates. Karyotypic analyses of first or second passage cultures yielded predominantly normal diploid cells. Nonclonal aberrations were more common in tumor-derived than in normal cultures. Three of the cultures that originated from metastases were characterized by abnormal clones. These results support observations based on DNA content, which indicate that a considerable fraction of breast cancers are composed predominantly of diploid cells. They differ greatly from chromosomal findings in long-term cultures of tumor effusions and thus emphasize the karyotypic diversity that can be found in tumors from a single tissue of origin--the breast.  相似文献   
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