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41.
E-cadherin and hereditary diffuse gastric cancer   总被引:2,自引:0,他引:2  
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The capacity of oral cholecystography (OCG), real-time ultrasound (RUS), and computed tomography (CT) to detect gallstones and to analyze their size, number, and composition was tested preoperatively in 37 patients undergoing elective cholecystectomy. Gallbladder response to a standard meal was also evaluated by OCG and RUS. Gallstones were analyzed chemically for calcium, cholesterol, and bilirubin content. The results show that RUS is the most valuable test for detecting gallstones and is similar to OCG in measuring their size and number, whereas CT underestimates the stone size. Gallbladder function in terms of contractability can be evaluated by RUS and OCG, but RUS provides useful information even if the gallbladder is not opacified at OCG. CT is more accurate than OCG in detecting the presence of calcium, and CT attenuation numbers are positively correlated with calcium content of the stone (r=0.87,p<0.01).  相似文献   
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The involvement of microRNAs (miRNAs) in chronic lymphocytic leukemia (CLL) pathogenesis suggests the possibility of anti-CLL therapeutic approaches based on miRNAs. Here, we used the Eμ-TCL1 transgenic mouse model, which reproduces leukemia with a similar course and distinct immunophenotype as human B-CLL, to test miR-181b as a therapeutic agent.In vitro enforced expression of miR-181b mimics induced significant apoptotic effects in human B-cell lines (RAJI, EHEB), as well as in mouse Eμ-TCL1 leukemic splenocytes. Molecular analyses revealed that miR-181b not only affected the expression of TCL1, Bcl2 and Mcl1 anti-apoptotic proteins, but also reduced the levels of Akt and phospho-Erk1/2. Notably, a siRNA anti-TCL1 could similarly down-modulate TCL1, but exhibited a reduced or absent activity in other relevant proteins, as well as a reduced effect on cell apoptosis and viability. In vivo studies demonstrated the capability of miR-181b to reduce leukemic cell expansion and to increase survival of treated mice.These data indicate that miR-181b exerts a broad range of actions, affecting proliferative, survival and apoptotic pathways, both in mice and human cells, and can potentially be used to reduce expansion of B-CLL leukemic cells.  相似文献   
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Total mercury and methylmercury concentrations were measured in sediments and marine organisms from the Taranto Gulf to understand their distribution and partitioning. Sediment concentrations ranged from 0.036 to 7.730 mg/kg (mean: 2.777 mg/kg d.w.) and from 1 to 40 μg/kg (mean: 11 μg/kg d.w.) for total mercury (THg) and methylmercury (Me-Hg), respectively. In mollusks THg ranged from n.d. to 1870 μg/kg d.w. while in fish from 324 to 1740 μg/kg d.w. Me-Hg concentrations in fish ranged from 190 to 1040 μg/kg d.w. and from n.d. to 1321 μg/kg d.w. in mollusks. THg exceeded the maximum level fixed by the European Commission (0.5 mg/kg w.w.) only in gastropod Hexaplex t. The calculated weekly intake was in many cases over the Provisional Tolerable Weekly Intake established by EFSA for all edible species. These results seem to indicate that dietary consumption of this seafood implicates an appreciable risk for human health.  相似文献   
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TCL1, the overexpression of which may result in T-cell leukemia, is normally expressed in early embryonic tissues, the ovary, and lymphoid lineage cells. Our analysis of mouse B-lineage cells indicates that Tcl1 expression is initiated in pro-B cells and persists in splenic marginal zone and follicular B cells. T-lineage Tcl1 expression begins in thymocyte progenitors, continues in CD4(+)CD8(+) thymocytes, and is extinguished in mature T cells. In Tcl1-deficient mice, we found B lymphopoiesis to be compromised at the pre-B cell stage and T-cell lymphopoiesis to be impaired at the CD4(+)CD8(+) thymocyte stage. A corresponding increase was observed in thymocyte susceptibility to anti-CD3epsilon-induced apoptosis. Reduced numbers of splenic follicular and germinal center B cells were accompanied by impaired production of immunoglobulin G1 (IgG1) and IgG2b antibodies in response to a T-dependent antigen. The marginal zone B cells and T-cell-independent antibody responses were also diminished in Tcl1(-/-) mice. This analysis indicates a significant role for Tcl1, a coactivator of Akt signaling, in normal T- and B-cell development and function.  相似文献   
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Purpose

The purpose of the present study was to analyze clinicopathologic features and long-term prognosis of gastric stump cancer (GSC) arising in the remnant stomach 5 years or later after partial gastrectomy for benign disease.

Methods

We reviewed the results of 176 patients resected with curative intent for GSC at 8 Italian centers belonging to the Italian Research Group for Gastric Cancer (GIRCG). The median (range) follow-up time for surviving patients was 71.2 (6–207) months.

Results

One hundred forty-six patients were men, the mean age at the time of diagnosis was 69.2 years, and the great majority (167 cases) underwent Billroth II reconstruction. R0 resection was achieved in 158 (90 %) patients, and in 94 (53 %) lymph node dissection was ≥D2. Postoperative mortality and complication rates were 6.2 and 43.2 %, respectively. T1 tumor was diagnosed in 45 (25 %) cases. Lymph node metastases were evident in 86 patients (49 %). Thirteen patients had involvement of the jejunal mesentery nodes (pJN+); five cases were T2–T3 and eight cases were T4. Overall 5-year survival rate was 53.1 %. Five-year survival rates were 68.1, 37.8, and 33.1 % for pT1, pT2-3, and pT4 tumors, respectively (P = 0.001). Five-year survival rate was 56.5 % for node-negative tumors (pN0), 32.3 % for tumors with nodal metastases without involvement of jejunal mesentery nodes (pN+), and 17.1 % for tumors with involvement of jejunal mesentery nodes (pJN+) (P = 0.002).

Conclusions

Our study suggests that an aggressive surgical approach can achieve a satisfactory outcome in GSC.  相似文献   
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