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Although grading of ovarian tumors is widely performed, the criteria for each grade are not well defined; as a result, pathologists tend to establish their own criteria without, however, assessing the actual predictive value of the criteria. In order to investigate this relationship, four gynecologic pathologists independently reviewed and carefully graded as benign, borderline or malignant (grade I, II or III) 40 "common" epithelial tumors of the ovary, without reference to clinical, prognostic or other findings. Intermediate grades were allowed. Subsequently, a subjective grading form was completed for each case; the form contained questions regarding the histologic and cytologic features. The sets of features with the biggest correlation with the tumor grades differed among the pathologists. This may indicate that the observers use different features in their grading processes. Moreover, the pathologist with the highest number (five) of significant microscopic features in the multivariate model had the lowest coefficient of correlation between his tumor grade and his feature set. The correlation coefficients for the other pathologists were quite similar, although the features used (no more than two or three) varied. The participants in the study felt that the methodologic approach had an educational value for them. Further investigations are required to evaluate whether the differences in the underlying decision making process also result in frank disagreement in ovarian tumor grading.  相似文献   
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Oxidative phosphorylation in intact Azotobacter vinelandii   总被引:3,自引:0,他引:3  
Baak JM  Postma PW 《FEBS letters》1971,19(3):189-192
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HER-2/neu oncoprotein overexpression was compared in fresh frozen and paraffin-embedded formalin-fixed invasive breast cancer material from the same patients. The HER-2/neu protein was detected by an immunohistochemical staining method, and the average amount of protein staining per cell was measured using the CAS-200 image analysis system and expressed relative to the amount of HER-2/neu protein of calibration cells of the SKBR3 cell line which are known to have amplification of the HER-2/neu gene and overexpression of the HER-2/neu protein. There was a significant correlation between degree of HER-2/neu protein overexpression and DNA-hyperdiploidy (P less than 0.01, chi 2 test). No significant correlation could be demonstrated between degree of HER-2/neu overexpression and tumor size, lymph node status, number of positive nodes or morphometric features. There was in general a good concordance (r = 0.83) in HER-2/neu expression values between fresh and paraffin-embedded material. Pairwise comparison of the two series (Wilcoxon signed ranks test) revealed no significant differences, indicating that there were no systematic differences between HER-2/neu assessments in fresh and paraffin material. When analysing the HER-2/neu expression values according to thresholds used earlier for overexpression, comparable results for fresh and paraffin material were obtained for most cases. In the fresh and paraffin material a different staining pattern was observed (more membrane staining in the fresh material in contrast to a more diffuse staining pattern in the paraffin material). It was concluded that both fresh-frozen and paraffin-embedded, formalin-fixed material is suitable for assessment of HER-2/neu protein overexpression by image analysis and provides comparable HER-2/neu expression values in most cases.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Transferrin, a glycoprotein involved in iron transport in body fluids, was isolated from amniotic fluid of a hydramniospatient by sequential anion-exchange chromatography and gel filtration. The N-glycans of human amniotic fluid transferrin (hAFT) were enzymatically liberated by PNGase-F digestion, isolated by gel filtration and fractionated by (high-pH) anion-exchange chromatography. After alkaline borohydride treatment of native hAFT, the released O-glycans were isolated by gel filtration and fractionated by anion-exchange chroma-tography. Structure elucidation of 14 N- and 2 O-glycans was performed by 500 or 600 MHz1H-NMR spectroscopy. Besides conventional N-glycans established earlier for human serum transferrin (hST), new (alpha1-3)-fucosylated N- glycans were found, representing sialyl Le(x) elements. Furthermore, as compared to hST, a higher degree of (alpha1-6)-fucosylation and an increase in branching from di- to triantennary compounds has been detected. The presence of O-glycans is demonstrated for the first time in transferrin.   相似文献   
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OBJECTIVE: To determine the influence of section thickness, nuclear diameter (MND) and area percentage of nuclei (a measure of nuclear crowding) on histologic DNA ploidy assessed by image cytometry (ICM) of primary melanocytic skin neoplasms (MSNs). STUDY DESIGN: Initially a feasibility study was performed to determine if comparable DNA ploidy histograms could be obtained from cell disaggregates and tissue sections. Following this, DNA ICM was performed on Feulgen-stained tissue sections (4, 6, 8 and 10 microns thick) from 30 primary MSNs (20 benign, 10 malignant) with nuclear diameters from 5.6 to 8.6 microns. Area percentage of nuclei was assessed in all cases at all section thicknesses. RESULTS: The feasibility study produced comparable results for cytocentrifuge and tissue section preparations. For sectioned MSNs, DNA ploidy histograms from 4-micron sections had a higher coefficient of variation of the 2c peak than those from 6-, 8- and 10-micron sections. Ten-micrometer sections had marked overlapping of nuclei, and only small numbers of cells could be measured, giving inadequate results. MND and area percentage of nuclei did not have an important influence on the results. CONCLUSION: Adequate DNA ploidy profiles can be obtained by DNA ICM on 6- and 8-micron-thick histologic sections of MSNs, provided that a strict measurement protocol is followed.  相似文献   
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