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41.
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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43.
Severe but atypical osteoarthritic deformities were found in each of 12 femoral heads removed during total hip arthroplasty for Mseleni disease. Although degenerative and regenerative changes were present throughout the cartilage, there was a paucity of eburnation. Histomorphometric analysis of bone at the line of excision indicated that mild osteomalacia was present in four of the 12 specimens. The percentage of the endosteum occupied by osteoid was 9.7 +/- 7.96 (SD) in the patients with Mseleni disease, compared with 5.6 +/- 4.33 in seven African black and 4.1 +/- 2.13 in 13 American white control subjects. The mean thickness of the osteoid seams was not increased. The findings suggest that osteomalacia is not a major pathogenetic factor in Mseleni disease. 相似文献
44.
Antibodies to pneumococcal polysaccharides in pneumonia and response to pneumococcal vaccination in young children in Papua New Guinea. 总被引:1,自引:0,他引:1 下载免费PDF全文
Antibodies against pneumococcal polysaccharides were measured by ELISA in Papua New Guinean children with pneumonia aged 0-14 months, in age-matched healthy Papua New Guinean controls and in healthy expatriate children living in Papua New Guinea. At 0-5 months of age, the IgG antibody titres against six of the eight polysaccharides measured were significantly lower in pneumonia patients than in both control groups. Antibody titres in 6-14-month-old Papua New Guinean controls were significantly lower than in control Papua New Guineans aged 0-5 months for five of the eight polysaccharides tested. In the 6-14-months age group the antibody titre was significantly lower in pneumonia patients than in controls for only one polysaccharide. For seven of the eight serotypes tested, antibody levels in expatriate controls did not decline with age. Antibody responses of Papua New Guinean children aged 6-18 months to a 23-valent pneumococcal vaccine were serotype dependent. Fold increases in response to the vaccine were greatest for the IgA isotype. IgG antibody responses were greater than three fold to four of the eight serotypes tested. 相似文献
45.
中国圆蝇亚科妙蝇属四新种(双翅目:蝇科) 总被引:1,自引:0,他引:1
冯炎 《寄生虫与医学昆虫学报》2005,12(4):216-221
在整理采自中国西部成蝇标本中,发现蝇科圆蝇亚科Mydaeinae妙蝇属Myospila Rondani,1856的4新种:春妙蝇Myospilavernatasp.nov.,黑前股妙蝇Myospila ateripraefemurasp.nov.,似净妙蝇Myospil alautoidessp.nov.,峨眉妙蝇Myospilaemeishanensissp.nov。前3种模式标本存中国科学院上海生命科学研究院植物生理生态研究所;后1种模式标本存军事医学科学院微生物流行病研究所医学昆虫标本馆。 相似文献
46.
R.S.K. Chaganti Roller B. Bailey Suresh C. Jhanwar Zalmen A. Arlin Bayard D. Clarkson 《Cancer Genetics and Cytogenetics》1982,5(3):215-221
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
47.
The familial prevalence in second-degree relatives of patients with anxiety neurosis (panic disorder) 总被引:1,自引:0,他引:1
A family history study of second-degree relatives of 19 patients with anxiety neurosis (panic disorder) and 19 controls showed a morbidity risk of 9.5% among the former compared with 1.4% among the latter. These risks were approximately half those found among first-degree relatives. Female relatives were at higher risk for anxiety neurosis. The risk for other psychiatric illnesses did not differ between the relatives of anxiety neurosis and controls. 相似文献
48.
49.
Monoclonal antibody identification of mononuclear cells in endomyocardial biopsy specimens from a patient with rheumatic carditis 总被引:3,自引:0,他引:3
A 17-year-old woman with rheumatic carditis underwent endomyocardial biopsy both prior to and following treatment with prednisone and aspirin. Frozen sections from the endomyocardial biopsy specimens were studied with monoclonal antibodies by an indirect immunofluorescence technique to define the composition of the inflammatory infiltrate in the myocardium and to determine whether the composition of the infiltrate is distinctive and diagnostically useful. The specimen from the initial biopsy contained a heterogeneous infiltrate composed of T lymphocytes, macrophages, B lymphocytes, and mast cells. T lymphocytes predominated, and the ratio of T-helper to T-cytotoxic/suppressor cells was 2.0. Following treatment the overall cellularity of the infiltrate was diminished, but the infiltrate remained heterogeneous; T cells predominated, and the T-helper to T-cytotoxic/suppressor ratio was reversed, to 0.59. The composition of the inflammatory infiltrate in this case of rheumatic carditis distinguishes it immunologically from other "idiopathic," presumably virus-associated, forms of myocarditis. 相似文献