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81.
Sclerosing breast lesions may sometimes mimic the appearance of infiltrating carcinoma due to the entrapment of ductular structures in a fibrotic core. The immunohistochemical detection of the outer myoepithelial cell layer that is indicative of a non-infiltrating lesion is a valuable clue for the diagnosis of such ambiguous cases. The myoepithelial cell markers smooth muscle actin (SMA) and p63 are most commonly used since their specificity and sensitivity are well established. However, recent studies have indicated that some morphologically distinct myoepithelial cells fail to stain for SMA and that p63 positivity can be rarely expressed by a subset of malignant epithelial cells. Moreover, SMA can also be positive in stromal myofibroblastic cells and normal vessels that can be found close to the entrapped ductules and might be erroneously interpreted as myoepithelial cells. In this study, we used a double-immunolabeling technique combining both SMA and p63 antibodies (myoepithelial cell cocktail), in order to investigate whether this technique is advantageous over either marker used alone, in diagnosing sclerosing breast lesions. Our results indicate that p63 alone is not a useful myoepithelial cell marker if applied in large sclerosing breast lesions, however, in smaller lesions it is still of high value. On the contrary, SMA proved significantly useful in the evaluation of myoepithelial cells in larger but not in smaller complex sclerosing lesions. The myoepithelial cell cocktail has a staining sensitivity identical to that of SMA. Nevertheless, in a certain number of cases the cocktail might be useful in differentiating myoepithelial cells from stromal myofibroblasts or vascular smooth muscle cells due to the false impression of a higher staining intensity of the cocktail resulting from the expression of both nuclear and cytoplasmic/membranous antibodies that occupy a wider area of the cell under control.  相似文献   
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83.
Homans  AC; Forman  EN; Barker  BE 《Blood》1985,66(6):1321-1325
The identification of small numbers of leukemic cells in the cerebrospinal fluid (CSF) presents a diagnostic problem in the treatment of children with acute lymphoblastic leukemia (ALL). We adapted a latex sphere rosetting technique to allow us to identify simultaneously cell surface markers and cell morphology in 199 CSF samples from 34 patients and 14 control subjects. In patients without leukemic meningitis, the majority of CSF lymphocytes (69%) were found to be mature T cells positive for OKT11. A much smaller number of cells (8%) were found to be B cells positive for la. In these children, only 3% of CSF lymphoid cells expressed the common acute lymphoblastic leukemia antigen (CALLA). Similar results were found in the control subjects. By contrast, 28 CSF samples from nine children with varying numbers of CSF lymphoblasts had much greater proportions of CALLA- and la-positive CSF cells (24% to 96%). Leukemic meningitis was present in one of these patients and later developed in four others. However, three patients with small numbers of lymphoblasts present but with low proportions of CALLA-positive CSF cells (less than 5%) subsequently had normal CSF examinations. We found the use of this rosetting technique valuable in providing information complementary to that obtained from cell morphology alone about the possible malignant nature of small numbers of lymphoblast-like CSF cells seen on cytocentrifuge preparations in children with ALL.  相似文献   
84.
Dessypris  EN; Redline  S; Harris  JW; Krantz  SB 《Blood》1985,65(4):789-794
The pathogenesis of diphenylhydantoin-induced pure red cell aplasia was investigated in the case of a 32-year-old man who developed pure red cell aplasia while he was under treatment with diphenylhydantoin. The patient's serum IgG purified from serum drawn at the time of diagnosis suppressed normal allogeneic marrow colony-forming (CFU-E) and burst- forming (BFU-E) and autologous blood BFU-E growth in vitro only in the presence of diphenylhydantoin. This IgG-diphenylhydantoin complex had no effect on CFU-GM growth in vitro. Normal IgG or patient's IgG purified from serum drawn after the remission of red cell aplasia had no effect on erythroid colony formation in vitro in the presence of diphenylhydantoin. The IgG-diphenylhydantoin complex exerted no direct cytotoxic effect on normal marrow erythroblasts, CFU-E, and BFU-E, nor did it interfere with the action of erythropoietin on marrow erythroblasts. These studies suggest that diphenylhydantoin-induced red cell aplasia is immunologically mediated through an IgG inhibitor, which requires the presence of the drug to suppress erythroid colony formation in vitro. This inhibitor seems to exert its effect on erythroid progenitors at or beyond the stage of differentiation of CFU- E, but not on erythroblasts.  相似文献   
85.
86.
Although bleomycin-induced cellular injury in the lung parenchyma is followed by the development of patchy fibrosis, the authors hypothesized that remodeling of the interalveolar septum (IAS) following bleomycin is a diffuse process not limited to the formation of discrete fibrotic areas. To determine the spectrum of changes in the IAS induced by bleomycin treatment, lungs were harvested from mice at 1, 2, 3, and 4 weeks following intratracheal administration of 0.04, 0.06, or 0.08 units of bleomycin. Light microscopy with quantitative morphometric techniques and electron microscopy were used to evaluate the IAS alterations. At 4 weeks after treatment, there was evidence of diffuse IAS remodeling. By morphological analysis, two types of structural remodeling of the IAS were observed. One type showed thickening with extracellular matrix deposition and hyperplasia of lining epithelial cells. The other type showed localized thinning of the interstitium with capillary loss and reduction in number and in size of epithelial cells. The authors have defined these variants as septal thickening and septal atrophy, respectively. The findings indicate that studies investigating the pathogenesis of lung fibrosis should focus on septal remodeling as well as analysis of fibrotic foci and measurement of collagen content.  相似文献   
87.
A protective effect of calcium and/or dairy products on colorectal cancer has been reported in epidemiological studies but the findings are considered inconsistent. In particular, it is unclear whether they act at a particular step of the adenoma-carcinoma sequence. To investigate the effect of dairy product consumption and dietary calcium, vitamin D and phosphorus intake on the adenoma-carcinoma sequence in the French E3N-EPIC prospective study. The population for the study of risk factors for adenomas was composed of 516 adenoma cases, including 175 high-risk adenomas, and of 4,804 polyp-free subjects confirmed by colonoscopy. The population for the colorectal cancer study was composed of 172 cases and 67,312 cancer-free subjects. Diet was assessed using a self-administered questionnaire completed at baseline. There was a trend of decreasing risk of both adenoma (ptrend=0.04) and cancer (ptrend=0.08) with increasing calcium intake, with RRs for adenoma and cancer of 0.80 (IC 95%=0.62-1.03) and 0.72 (95% CI=0.47-1.10), respectively, in the fourth quartile compared to the first. A protective effect of dairy products on adenoma (RRQ4 vs. Q1=0.80, 95% CI=0.62-1.05, ptrend=0.04) was observed and of milk consumption on colorectal cancer (RRQ4vs. Q1=0.54, 95% CI=0.33-0.89, ptrend=0.09), although the latter did not reach significance. Phosphorus intake also decreased the risk of adenoma (RRQ4 vs. Q1=0.70, 95% CI=0.54-0.90, ptrend=0.005). No vitamin D effect was identified. Our data support the hypothesis that calcium, dairy products and phosphorus exert a protective effect at certain steps of the adenoma-carcinoma sequence.  相似文献   
88.
Angiogenesis is implicated in the progression of myelodysplastic syndromes (MDS). Bone marrow microvascular density (MVD), serum angiogenin (ANG) and interleukin 6 (IL-6) were measured in 67 patients with untreated MDS. MVD, ANG and IL-6 were significantly higher in the patient group as a whole when compared to controls (P < 0.01). MVD and ANG were significantly higher in subtypes with a high-risk for leukemic transformation (RAEB, RAEB-t and CMML) than in low-risk subtypes (RA and RARS) (P < 0.01). In the MDS group, a positive correlation was found between ANG and IL-6 (P < 0.001) and also between MVD and IL-6 (P < 0.05). Using multivariate analysis, only IL-6 displayed independent prognostic value and was inversely related to MDS survival.  相似文献   
89.
Purpose: This is a phase II study where a novel chemotherapy combination was tested in pre-treated breast cancer patients: docetaxel and irinotecan have already been established as agents for breast and colorectal cancer, respectively. Methods: Forty-eight (median age 54 years, range 26–77 year) patients, all evaluable, were enrolled. All patients had been pre-treated with anthracycline-combined chemotherapy, 30 of whom were also treated with paclitaxel and 2 with docetaxel. World Health Organization (WHO) performance status was 0–2. The dominant metastasis was in the liver (54.17%), in the lungs (27.08%), in soft tissues (12.50%) and in the skeleton (6.25%). Treatment involved irinotecan infusion 200 mg/m2 for 90 min and docetaxel infusion 80 mg/m2 for 90 min, repeated once every 3 weeks. Results: Twenty-five (52.08%, 95% confidence interval [CI] 37.95–66.21) patients showed responses: 3 complete (6.25%, 95% CI 0–13.05) and 22 (45.83%, 95% CI 31.74–59.92) partial; the most responsive metastases were observed at the liver site (53.85%). Grade 3 and 4 neutropenia was observed in 18 patients (37.50%); 14 (29.17%) patients developed anaemia and three (6.25%), thrombocytopenia. Concerning non-haematologic toxicity, alopecia and fatigue were common; grade 3 diarrhea was observed in only one (2.08%) patient. Conclusion: The irinotecan-docetaxel combination produces quite a high response rate in pre-treated advanced breast cancer patients.  相似文献   
90.
Recent studies have documented that angiogenesis plays a significant role in haematological malignancies, including mylodysplastic syndromes (MDS). Basic fibroblast growth factor (b-FGF), Hepatocyte growth factor (HGF) and Tumor necrosis factor-alpha (TNF-alpha) are multifunctional cytokines that potently stimulate angiogenesis. The aim of the present study was to evaluate the microvascular density (MVD) and the serum levels of these angiogenic factors in patients with myelodysplastic syndromes (MDS). In 61 patients with MDS, MVD was measured in bone marrow biopsies and b-FGF, HGF and TNF-alpha were determined in the serum of the same patients by enzyme-linked immunosorbent assay (ELISA). Serum levels of b-FGF, HGF and TNF-alpha as well as MVD in the bone marrow were increased in MDS patients compared to healthy controls (p<0.0001). Levels of b-FGF, HGF and TNF-alpha were also significantly higher in high-risk for leukemic transformation MDS than in low-risk (p<0.0001). Significant differences were also found regarding MVD in high and low risk patients (p<0.001). Both b-FGF and HGF levels were significant predictors of survival (p<0.0005, log-rank test). The present study showed that serum levels of b-FGF, HGF and TNF-alpha are significantly increased and dependent on the severity of MDS suggesting that the determination of these parameters may offer considerable information regarding disease progression and prognosis.  相似文献   
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