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31.
The purpose of this study was to evaluate the ability of MRI to identify a primary site of malignancy in the breast of patients who present clinically with ipsilateral lymph nodes containing metastatic carcinoma but whose physical and mammographic examination are negative. MRI of the breast was performed on four patients using a variety of imaging parameters, all with and without gadolinium contrast. All patients had biopsy-proven adenocarcinoma of the ipsilateral axilla, with negative physical and mammographic examinations. Foci of enhancement assessed visually on precontrast and postcontrast scans (n = 1) and on substraction studies (n = 3) were considered suspicious under the clinical circumstances defined for this study. Lesions identified on MRI were re-identified on ultrasound examination and either preoperative localization for excisional biopsy or tissue sampling was performed. Surgery was performed and histopathologic correlation was obtained in all cases. Primary sites of breast carcinoma were identified in all four patients, with multiple sites of malignancy identified in three of four patients. Breast conservation therapy was made possible for three of four patients based on the results of the MRI study showing sites of malignancy and no features of cancer elsewhere in the breast. Follow-up data of 1, 2, and 5 years of these patients show no evidence of recurrent disease. MRI of the breast is a useful technique for identifying primary sites of malignancy in patients presenting with ipsilateral lymph nodes positive for metastatic adenocarcinoma when the physical and mammographic examinations are negative. 相似文献
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Delirium in liver transplantation candidates: discriminant analysis of multiple test variables 总被引:1,自引:0,他引:1
We report the results of electroencephalograms, Mini-Mental State exam, Trailmaking Tests A and B, and serum albumin levels in 108 consecutive liver transplantation candidates. We compared test results to a clinical DSM-III diagnosis of delirium. Although each variable could differentiate between the two groups (delirium n = 18; nondelirium n = 90) at a statistically significant level, a discriminant analysis involving either all variables or only three particular variables (Trailmaking B, EEG code, and albumin) resulted in the highest specificity (97.8%) and sensitivity (83.3%), with a correct classification of 95.4% of subjects. The analysis also generates an equation that can be applied to clinical situations to enhance the accurate recognition of delirium. In addition, to explain abnormal Trailmaking B scores and/or EEGs in subjects who did not otherwise meet DSM-III criteria for delirium, we suggest the presence of a "subclinical delirium." 相似文献
36.
Directed establishment of rat brain cell lines with the phenotypic characteristics of type 1 astrocytes. 下载免费PDF全文
E H Radany M Brenner F Besnard V Bigornia J M Bishop C F Deschepper 《Proceedings of the National Academy of Sciences of the United States of America》1992,89(14):6467-6471
Interest in obtaining cell lines for use in studies on the development and biochemistry of the central nervous system has motivated efforts to establish cells from primary brain cultures by the use of oncogene-transfer techniques. In previous reports, cell lines derived from astrocytes in this way have had immature or abnormal phenotypes. We have explored the possibility of specifically "targeting" expression of exogenous oncogenes to differentiated astrocytes by using the promoter of the gene encoding glial fibrillary acidic protein, which is expressed almost exclusively in such cells. We report here that cell lines displaying the phenotypic characteristics of type 1 astrocytes can be established reproducibly in this manner. Given the heterogeneity of primary cultures, the availability of clonal cell lines displaying characteristics of type 1 astrocytes should greatly facilitate our understanding of the biology of these cells. 相似文献
37.
Thorsten Sch?fer 《Infection》1992,20(6):312-312
Information
1992 science award of the Paul-Ehrlich-Gesellschaft für Chemotherapie e.V. 相似文献38.
Comparison of DNA adducts and sister chromatid exchange in lung cancer cases and controls 总被引:3,自引:0,他引:3
F Perera J Mayer A Jaretzki S Hearne D Brenner T L Young H K Fischman M Grimes S Grantham M X Tang 《Cancer research》1989,49(16):4446-4451
In a molecular epidemiological study of lung cancer cases (n = 81) and noncancer controls (n = 67), polycyclic aromatic hydrocarbon (PAH)-DNA adducts were evaluated in peripheral blood leukocytes from all subjects and in a smaller number of lung tissue specimens collected prior to or at surgery. Sister chromatid exchanges (SCE) in lymphocytes were also studied in a subset of cases and controls. Questionnaire, medical record, or tumor registry data provided a family history of cancer, as well as information on cigarette smoking, dietary and occupational exposure to PAHs, and other factors related to SCEs. In both cases and controls PAH-DNA adducts in leukocytes measured by an enzyme-linked immunosorbent assay were not significantly related to age, sex, ethnicity, amount of cigarette smoking, passive smoking, dietary charcoal, or caffeine consumption. Nor did family history of cancer or histological type of cancer significantly affect adduct levels. However, when subjects were stratified by smoking status (current, former, and nonsmoker), lung cancer cases who were current smokers had significantly higher levels of covalent adducts than current smoker controls. A seasonal variation was observed in PAH-DNA binding, with a peak in adduct levels during July-October. This peak corresponds to that seen in a prior study of aryl hydrocarbon hydroxylase inducibility by other investigators. The finding of significant levels of PAH-DNA adducts in former smokers and non-smokers supports an earlier observation that this marker is not smoking specific but reflects a pervasive and variable "background" exposure to PAH. These results are consistent with a genetically determined enhancement of PAH-DNA adduct formation in leukocytes of lung cancer cases which is evident in current smokers. The results in lung tissue are limited by the small number of samples. Adduct levels were not significantly increased in lung tissue of smokers compared with nonsmokers. An inverse linear correlation was seen between adduct values in lung tissue and age of the donors. SCEs were significantly related to pack years of smoking. However, there was no difference in the frequency of SCE between cases and controls; nor were SCE and DNA adducts significantly correlated in this small sample. 相似文献
39.
Hewlett D Warner C Brenner LK 《The Journal of allergy and clinical immunology》2003,112(6):1246; author reply 1246-1246; author reply 1247
40.
Taillandier A Zurutuza L Muller F Simon-Bouy B Serre JL Bird L Brenner R Boute O Cousin J Gaillard D Heidemann PH Steinmann B Wallot M Mornet E 《Human mutation》1999,13(2):171-172
Hypophosphatasia is a rare inherited disorder characterized by defective bone mineralization and deficiency of serum and tissue liver/ bone/kidney tissue alkaline phosphatase (L/B/K ALP) activity. We report the characterization of tissue-nonspecific alkaline phosphatase (TNSALP) gene mutations in a series of 9 families affected by severe hypophosphatasia. Fourteen distinct mutations were found, 3 of which were previously reported in the North American or Japanese populations. Seven of the 11 new mutations were missense mutations (M45L, R119H, G145V, C184Y and H154Y, D289V, E459K), the four others were 2 single nucleotide deletions (544delG and 1172delC), a mutation affecting donor splice site (862 + 5A) and a nonsense mutation (R411X). 相似文献