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OBJECTIVE: To determine whether nuclear morphometry can confirm or add useful information to classic clinicopathological prognosticators to identify the subpopulation of breast carcinoma patients with node-negative (N-) disease, at high risk of disease relapse. STUDY DESIGN: On the basis of results obtained by clinicopathologic evaluation of a group of patients with N- breast cancer, on a test group of 56 cases (32 patients disease free and 24 with relapse), we performed a morphometric analytical study of nuclei using the Shape Analytical Morphometry (SAM) software system; 20 nuclei for each case and 17 morphometric parameters for each nucleus were analyzed. RESULTS: The SAM system allowed us to quantify shape differences in nuclei in terms of contour irregularities and asymmetries along with evaluation of nuclear dimensions. Dimensional and analytic parameters were subjected to univariate (Student's t test) and multivariate (Hotelling's test) analysis. Multivariate discriminant analysis showed that an exact forecast of disease relapse could be made in 77% of patients with N- breast cancer by using a set of six both analytic and dimensional parameters. CONCLUSION: These results confirm that nuclear pleomorphism is the result of both contour irregularities and shape asymmetries and that even though they should be considered preliminary results, they stress the importance of quantitative shape evaluation.  相似文献   
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This retrospective study compares the tympanoplasty success rate when using a xenograft (Zenoderm) or an autograft (temporalis fascia). Fifty-three ears were operated on over a three-year period. All the tympanoplasty operations were performed by the same surgeon. There were 43 ears in the temporalis fascia autograft group and 10 ears in the Zenoderm xenograft group. Both groups were similar with respect to patient age, type of tympanoplasty, area of tympanic membrane perforation and condition of the contralateral ear. The tympanoplasty success rate in the temporalis fascia autograft group was 95 per cent. The tympanoplasty success rate in the Zenoderm xenograft group was only 40 per cent. All Zenoderm tympanoplasty failures were regrafted with temporalis fascia autograft. There was a 100 per cent success rate with this salvage surgery. In conclusion, we suggest that Zenoderm is not a suitable graft material for tympanoplasty.  相似文献   
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PURPOSE: To define the frequency of development of pupillary membranes after ECCE with PC-IOL implantation, and to remove the pupillary membranes using the Nd:YAG laser. METHODS: From 400 patients who had undergone ECCE and were free from local or systemic illness affecting the blood-ocular barrier, 20 eyes developed pupillary membranes Nd:YAG laser was used to remove these pupillary membranes. RESULTS: The frequency of pupillary membranes was found to be 5% (9.8% in pex eyes and 3.3% to the non-pex eyes). Visual acuity improved in 17 eyes by 2 to 5 Snellen lines. No serious complications were observed, endothelium inclusive. CONCLUSION: Pseudoexfoliation might play a significant role in the development of postoperative pupillary membranes which could be successfully treated with the use of Nd:YAG laser. The safety of the procedure has to be evaluated in relation to the corneal endothelium damage in long-term.  相似文献   
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BACKGROUND: Endoscopic diagnosis of short segments of Barrett's epithelium (SSBE)' is difficult and its meaning in terms of the presence of specialised columnar epithelium (SCE) has not been prospectively evaluated. AIMS: To evaluate the prevalence of SCE in patients with an endoscopic diagnosis of SSBE and in individuals with normal appearing oesophagogastric junctions, and to compare the clinical characteristics of these two groups. PATIENTS: Thirty one patients with an endoscopic diagnosis of short Barrett's oesophagus, less than 3 cm in length (group A), and 44 consecutive patients with normal appearing oesophagogastric junctions (group B). METHODS: Multiple biopsies were performed in suspicious epithelium and at the oesophagogastric junction in groups A and B, respectively. RESULTS: Age and sex distribution were similar in both groups. Reflux symptoms were more frequent in group A (p < 0.001), as were endoscopic and histological signs of oesophagitis (p < 0.001 and p = 0.001, respectively). SCE was found in 61.3% of group A patients compared with 25% in group B (p < 0.002), with men predominating in group A while women were more frequent in group B (p = 0.02). The differences in reflux symptoms and endoscopic/histological oesophagitis remained significant. CONCLUSIONS: These results show that endoscopic diagnosis of SSBE is associated with a high prevalence of SCE, significantly higher than that found in normal appearing oesophagogastric junctions. Differences between patients with SCE in the two groups suggest they may represent two different entities.  相似文献   
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Binding of apoB-containing lipoproteins from unfractionated human blood sera to the immobilized bovine receptor of low density lipoproteins (LDL receptor) was studied. Peroxidase-labeled anti-human apoB antibodies were used to evaluate the lipoprotein binding. The equilibrium dissociation constant (Kd) of the interaction between apoB-containing lipoproteins from unfractionated human sera from healthy donors and the immobilized LDL receptor varied from 1 to 20 microg apoB/ml. To describe the binding of lipoproteins to the LDL receptor, a parameter of relative binding affinity (RBA) was used. RBA is inversely related to value of Kd and equal to unity for the standard serum. The RBA values for the binding of apoB-containing lipoproteins from unfractionated sera to the immobilized LDL receptor were found to correlate with the RBA values for the binding of isolated VLDL (r = 0.76, p < 0.001) and fail to correlate with the RBA values for the binding of isolated LDL. The RBA values for the binding of apoB-containing lipoproteins from unfractionated sera correlated with the RBA values for the binding of apoE-containing lipoproteins from unfractionated sera (r = 0.92, p < 0.001) and with values of triglyceride concentration in the sera (r = 0.93, p < 0.001). The RBA values for the binding of apoB-containing lipoproteins from sera of patients with FDB whose LDL were unable to bind to the LDL receptor did not significantly differ from the RBA values for the normal sera. However, the removal of VLDL from the normal sera significantly decreased the RBA values for the binding of apoB-containing lipoproteins from unfractionated sera. The results indicate that the different binding of apoB-containing lipoproteins to the immobilized LDL receptor mainly depended on the different binding of VLDL and not of LDL.  相似文献   
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