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61.
BACKGROUND: An early immunologic study suggesting that a virus similar to the mouse mammary tumor virus (MMTV) was associated highly with breast carcinoma in Tunisian patients, compared with patients in the United States, led the authors to examine different breast carcinoma populations by using more current molecular techniques. METHODS: Thirty-nine paraffin blocks were selected for sequencing of the 250-base pair segment of the MMTV from patients with breast carcinoma who were seen and treated at the Institut Salah Azaiz in Tunisia. Fifteen of those blocks were examined under code by a second laboratory, which used a different methodology and was blinded to the results of the first laboratory, and 14 blocks were analyzed successfully. RESULTS: The comparison of Tunisian patients and patients from other countries clearly showed a significantly higher proportion of tumors with MMTV-like sequences in the Tunisian series of patients. There was complete reproducibility of data between the two laboratories. Using the results from the first laboratory and similar studies from the literature, detection of the MMTV-like env gene sequence showed an important geographic pattern with a significantly higher percentage of positive patients with breast carcinoma in Tunisia (74%) compared with patients with breast carcinoma in the United States (36%), Italy (38%), Australia (42%), Argentina (31%), and Vietnam (0.8%) CONCLUSIONS: The findings provided increased evidence for a human breast carcinoma virus with geographic differences in prevalence. The geographic differences were compatible with studies of MMTV in wild mice; thus, the data were plausible biologically.  相似文献   
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An 82-year-old woman presented with a right breast lump with erythematous reaction of the overlying skin and corresponding lymph nodes. Cytological examination of the breast lesion and lymph nodes suggested a lymphoid proliferation. Frozen section revealed carcinoma with lymphoid stroma. Simple mastectomy was performed because of the extent of the lesion. Histological diagnosis was non-Hodgkin type B large-cell lymphoma. Primary breast lymphomas behave similarly to lymphomas of similar histologic types occurring in other sites. The authors illustrate the diagnostic difficulties and the usefulness of complementary techniques in the diagnosis of an unusual breast mass.  相似文献   
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Expression of the urokinase plasminogen activator (uPA) increases during the progression of colorectal tumors from adenomas to carcinomas. The highest amounts of uPA are found at the invasion front of carcinomas, which also displays a strong expression of nuclear beta-catenin and is therefore a region expressing beta-catenin target genes at high levels. Here we show that beta-catenin contributes to the transactivation of uPA. Therefore, beta-catenin might have an impact on the capacity of colorectal tumors for invasion and metastasis, as well as dormancy, which are hallmarks of cancer.  相似文献   
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Fixed dosing is potentially more convenient than weight-based dosing for both patients and physicians. Therefore, this open-label, randomized (1:1), multicenter study was conducted to compare the effectiveness, safety, and quality-of-life benefits of fixed vs. weight-based dosing of epoetin alpha in anemic cancer patients undergoing chemotherapy. Five hundred forty-six anemic patients undergoing platinum-based chemotherapy for solid malignancies were enrolled. Patients received epoetin alpha, either a fixed dose of 10,000 IU or a weight-based dose of 150 IU/kg, administered subcutaneously 3 times weekly for up to 12 weeks. Endpoints were transfusion requirements over days 29-84, change in hemoglobin (Hb) level from baseline, and change in quality-of-life (QOL) scores from baseline as measured using the Cancer Linear Analog Scale (CLAS). Five hundred and thirty-two patients received at least 1 dose of epoetin alpha, and 510 of these (255 in each treatment group) were considered evaluable for efficacy. At day 84, rates for freedom from transfusion were similar between the fixed-dose and the weight-based dose group (84% vs. 87%, respectively, p=0.32), as calculated by the lifetable method. These rates were also similar between patients in the 45-63 kg weight group receiving the fixed 10,000 IU dose or 7,000-9,000 IU on a per-weight basis (83% vs. 87%, respectively), and those in the 70-100 kg weight group receiving the fixed 10,000 IU dose or 11,000-15,000 IU on a per-weight basis (85% vs. 83%, respectively). Mean Hb increases from baseline to last observation were 2.10 g/dl [95% confidence intervals (CI95) 1.85-2.35] in the 10,000 IU group (from 9.64-11.74 g/dl) and 2.06 g/dl (CI95 1.82-2.30) in the 150 IU/kg group (from 9.70-11.76 g/dl). QOL results were similar for both groups and cumulative data have been reported. For 275 patients (in both groups combined) with CLAS QOL scores both at baseline and 29-98 days thereafter, the QOL index (average of scores for the 3 QOL parameters: energy level, ability to do daily activities and overall QOL) increased by 10.4 mm (CI95 7.5-13.2), from 46.2 mm at baseline to 56.6 mm at the final observation. QOL improvements were directly associated with Hb increases (p<0.001, multiple linear regression analysis) within all chemotherapy response classes. Epoetin alpha was well tolerated in both groups. Fixed (10,000 IU) and weight-based (150 IU/kg) dosing regimens of epoetin alpha demonstrated similar efficacy in maintaining freedom from transfusion, increasing Hb levels, and improving QOL in anemic cancer patients undergoing platinum-based chemotherapy. QOL improvements were directly associated with Hb increases. These findings support the use of a fixed-dose regimen of epoetin alpha, which may offer greater convenience for physicians and patients than weight-based dosing with this agent.  相似文献   
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OBJECTIVES: A lower ratio in the classic activated protein C resistance (APC-R) test has been reported during pregnancy, which has been called 'acquired' APC-R. However, little is known about the cause of the lowered ratio, and whether or not there is a correlation with blood coagulation activation. The primary objective of our study was to determine changes in APC-R levels in each of the trimesters of normal pregnancy. The secondary objective was to confirm whether APC-R levels were lower in pregnancies complicated by pre-eclampsia than in a control group. Finally, this prospective study was performed to investigate the prevalence of APC-R among pregnant women and to elucidate its obstetric consequences. METHODS: We enrolled 35 healthy pregnant women and 47 pregnant women affected by pre-eclampsia in our study. The following laboratory tests were performed: prothrombin time, partial thromboplastin time, fibrinogen levels, antithrombin III, plasmatic fibronectin (as a marker of endothelial damage), haptoglobin (as a marker of intravascular haemolysis), a functional test for APC-R and analysis of factor V Leiden mutation by polymerase chain reaction. RESULTS: The activated protein C sensitivity ratio was lower in the pathological group than in the control group (p = 0.008 and p = 0.02, respectively). Plasmatic fibronectin was found to be higher in the pathological group than in the control group (p = 0.05). Finally, the overall prevalence of factor V Leiden mutation was 5.4%, i.e. 2/35 women (5.7%) in the control group and 3/47 women in the pathological group (6.38%). CONCLUSIONS: The APC ratio decreased after 20 weeks of gestation until week 42. This decrease was most pronounced in the third trimester, in which resistance was demonstrated in 34.2% of control group patients. In pre-eclampsia, we found a greater reduction of the APC ratio than in controls. We hypothesise that this is due to a decrease in the plasmatic levels of coagulation inhibitors and an increase in coagulatory factors.  相似文献   
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