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991.
992.
Chromosome counts were performed on 1,100 cells from 17 malignant breast carcinomas and on 168 cells of four normal tissue samples after amethopterin treatment and G-banding. Karyotypes were established from 216 cells of 11 tumor-derived cultures and from 47 cells of four nonmalignant tissue-derived cultures. Karyotypes of cells from nonmalignant samples showed a normal diploid chromosomal constitution with no consistent loss or gain of a specific chromosome. Structural chromosomal abnormalities were not observed. Tumor-derived cultures could be distinguished from normal cultures on the basis of a significantly increased incidence of numerical changes and structural chromosomal aberrations. In nine of 11 tumor-derived cultures, numerically normal cells were shown to be pseudodiploid, with frequencies ranging to 43% (mean, 13.2%) of the diploid cells. In agreement with previous reports, cytogenetic analyses showed predominantly diploid cells. Clonal numerical changes of chromosomes 17, 18, 20, and 21 could be detected in three tumor samples. Clonal structural abnormalities could be observed in two of 11 analyzed tumours. A t(6;12)(p21;p13) and an enlarged chromosome 7 (7q+) were found in a patient with invasive ductal carcinoma. An inversion of chromosome 7 [inv(7)(q11.2q32)] was observed in one case, also diagnosed as invasive ductal carcinoma. The significance of these findings in relation to clinical data is discussed.  相似文献   
993.
B?rjeson-Forssman-Lehmann syndrome: further delineation in five cases   总被引:1,自引:0,他引:1  
We have studied five males with B?rjeson-Forssman-Lehmann syndrome (BFLS) from two unrelated families. They had a characteristic facial appearance with prominent supraorbital ridges, deep-set eyes, ptosis, and large ears, as well as obesity, severe mental retardation, hypotonia, and hypogonadism. Ophthalmologic, EEG, and skeletal abnormalities were also present. The findings in several presumed or possible heterozygous women were evaluated and suggested a wide range of phenotypic effects varying between apparent normality to mild or moderately evident BFLS manifestations. The observed pattern of occurrence of the BFLS in our two families provides strong support for X-linked inheritance. In clinically normal female relatives at risk for being carriers of BFLS, we have been unsuccessful in identifying a reliable screening test. The condition in our and previously reported patients was contrasted with other malformation syndromes and our findings support the conclusion that BFLS is a distinct and clinically identifiable disorder.  相似文献   
994.
995.
996.
Cytogenetic analysis of a uterine lipoleiomyoma.   总被引:2,自引:0,他引:2  
We cytogenetically analyzed a uterine lipoleiomyoma. A primary chromosomal abnormality, t(12;14), was found in all 62 cells studied. A secondary change involving chromosomes 1 and 5 was detected in 15 of 62 cells. These findings suggest that lipoleiomyomas share the same chromosomal abnormalities found in common leiomyomas. We speculate that the secondary chromosomal change involving chromosomal 5 may be responsible for the lipomatous change.  相似文献   
997.
998.
Summary A case of malignant endocrine tumour of the jejunum, associated with severe duodenal ulcer is described. The tumour and a local metastasis were examined by immunohistochemistry and found to contain abundant somatostatin-immunoreactive cells together with less numerous cells displaying gastrin immunoreactivity. This is to our knowledge the first case of intestinal somatostatinoma. The presence of gastrin cells in the tumour may explain the ulcer diathesis.  相似文献   
999.
The sera of ten patients with unexplained hypoglycaemia were examined for antibodies to pancreatic islets. Antibodies to pancreatic A, B and D cells (ICAb) were detected in one patient with an associated gastrointestinal tumour.  相似文献   
1000.
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