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The CD5 antigen is a T-cell associated marker that is also usually expressed by two B-cell neoplasms, chronic lymphocytic leukemia/small lymphocytic lymphoma and mantle cell lymphoma. We observed CD5 antigen expression in a subset of cases of intravascular large B-cell lymphoma (IVLBL), and we report here five cases. The patients, two men and three women, ranged in age from 59 to 81 years. Biopsy specimens were obtained from kidney, lung, bone marrow, abdominal wall, and neck, the latter involving a lymphangioma. All of the cases had histologic features typical of IVLBL, with large and atypical lymphoid cells located predominantly within blood vessels. Immunohistochemical studies performed using routinely fixed, paraffin-embedded tissue sections showed that the neoplastic cells were B cells, positive for the CD20 antigen and negative for the CD3 or CD43 antigens. All cases were also positive for the CD5 antigen. One case had an immunoglobulin heavy chain gene rearrangement shown by using a polymerase chain reaction method. The finding of CD5 antigen expression in a subset of IVLBL cases adds to other evidence in the literature suggesting that IVLBL is a heterogeneous entity. We considered the possibility that these cases were related to or represented unusual histologic forms of transformation from either chronic lymphocytic leukemia/small lymphocytic lymphoma or mantle cell lymphoma. All of the cases, however, were negative for the CD23 antigen and cyclin D1 (bcl-1) protein, which is evidence against this interpretation. The biologic significance of CD5 antigen expression in cases of IVLBL is uncertain. These neoplasms might arise from a separate lineage of CD5-positive B cells or from a specific, early stage of B-cell differentiation. Alternatively, some investigators have suggested that CD5 antigen expression by B cells is a marker of activation.  相似文献   
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The purpose of this study was to determine the sensory properties and acceptability of lab developed prototypes of conventional, diabetic (with no sugar), and diabetic/reduced calorie milk chocolates (no sugar and 25% calorie reduction) with high-intensity sweeteners, sucralose and stevioside, and partial fat replacement with whey protein concentrate (WPC). PLS was performed in order to relate sensory properties and consumer acceptability and to determine drivers of liking and disliking. There was no difference between conventional, diabetic and diabetic/reduced calorie milk chocolates for brightness, cocoa aroma, cocoa butter aroma, and cocoa flavor (p > 0.05). Acceptability was higher for sucrose substitution by sucralose than by stevioside and partial fat replacement reduced acceptability of flavor even more (p ? 0.05). Crucial attributes which determine consumer acceptability in samples are sweet aroma, melting rate, and sweetness, whereas bitterness, bitter aftertaste, adherence, and sandiness were drivers of disliking.  相似文献   
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Changes in the management of trauma over the past few years are significantly affecting postgraduate surgical education, with the lack of operative trauma experience being a major concern in some programs. This problem is accentuated in residency programs that obtain their trauma caseload primarily from blunt injury. Our experience over the past 6 years confirms that the growing trend toward nonoperative management of blunt liver and spleen injuries in adults is likely to exacerbate this problem. Blunt trauma admissions to our Level I trauma center increased from 2888 from 1991 through 1993 (group A) to 3587 from 1994 through 1996 (group B). Liver and/or splenic injuries occurred with equal frequency in both groups. Whereas diagnostic peritoneal lavage was used in 26 per cent of group A, its use dropped to 2 per cent in group B as abdominal computerized tomography was used more frequently to evaluate these patients. Nonoperative management increased from 10 per cent of group A to 54 per cent of group B. As a result, therapeutic laparotomies dropped from 85 in group A (58% of patients with liver/splenic injuries) to 74 (35%) in group B and nontherapeutic laparotomies from 48 (33%) to 23 (11%). While the evolution in the management of blunt liver and splenic injuries has resulted in the avoidance of nontherapeutic laparotomies, the operative caseload available to surgical housestaff has been adversely affected. Although the Residency Review Committee has stressed the importance of the critical care management of these patients, the criteria used to evaluate the number of trauma cases in postgraduate surgical education may need to be revised.  相似文献   
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PURPOSE: To compare immediate and long term results balloon mitral valvuloplasty (BMV) using double balloon or bifoil balloon. METHODS: One hundred and thirteen consecutive cases of BMV used aleatory double balloon (group DB--55 cases) or bifoil balloon (group BF--16 cases). Patients were similar regarding to age, sex, valvopaty etiology, functional class and echocardiographic score. Seventy one (63%) patients achieved 12 months follow-up. RESULTS: In group DB there were 2 (4%) insuccess, 2 (4%) cardiac tamponade and 2 (4%) deaths, 91% patients had immediate criteria of success. Mitral valve area (MVA) increased from 0.8 to 1.69cm2 and mitral gradient (G) by echodopplercardiographic (ECHO) decreased from 17.9 to 4.8mmHg. Three (5%) patients developed severe mitral regurgitation (MR) and needed surgical intervention. At follow-up 2 (4%) developed mitral restenosis. MVA estimated by ECHO study after one year follow-up was inferior to 1.15cm2 in 15 (32%) cases, between 1.5 and 2.0cm2 in 17 (37%) and superior to 2.0cm2 in 14 (31%). In group BF there were 2 (12.5%) insuccess, 4 (25%) developed severe MR occurring 1 death immediate post-operative mitral valve replacement. Among 14 (87%) success cases, MVA increased from 0.8 to 1.89cm2 and G decreased from 18 to 6.4mmHg. Lately 2 (12.5%) needed surgical intervention because significative MR. At 12th month follow-up the ECHO study showed that in one (10%) case MVA was < 1.5cm2, and in 3 (27%) cases was between 1.5 and 2.0cm2. CONCLUSION: There were similar good results in both groups, however group DB had more restenosis, cardiac tamponade and vascular complications and group BF had more severe MR.  相似文献   
56.
A new process design method for controlling microstructure development during hot metal deformation processes is presented. This approach is based on modern control theory and involves state- space models for describing the material behavior and the mechanics of the process. The challenge of effectively controlling the values and distribution of important microstructural features can now be systematically formulated and solved in terms of an optimal control problem. This method has been applied to the optimization of grain size and certain process parameters such as die geometry profile and ram velocity during extrusion of plain carbon steel. Various case studies have been investigated, and experimental results show good agreement with those predicted in the design stage.  相似文献   
57.
In this work we study the propagation of exciton-polaritons (bulk and surface modes) in a binary superlattice ABAB…, truncated at z=0, where z is defined as the growth axis. Here A is the spatially dispersive medium, which alternates with a common dielectric medium B (sapphire-Al2O3). The excitonic medium (A) is modelled by a semiconductor from the nitride's family (III-V semiconductor) that has, as a main characteristic, a wide-direct gap. The exciton-polariton spectrum is determined, in both s and p-polarization, by using standard electromagnetic boundary conditions, together with an additional boundary condition (ABC) for the Wannier-Mott excitons, employing a transfer-matrix formalism to simplify the algebra. The dispersion relation shows a bottleneck profile for the superlattice modes, whose behavior is similar to those found in the bulk crystal. Furthermore, interesting properties are revealed from the ABC as well as from different ratios of the thickness of the two superlattices alternating materials.  相似文献   
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Unripe coconut fibers were used as fillers in a biodegradable polymer matrix of starch/ethylene vinyl alcohol (EVOH)/glycerol. The effects of fiber content on the mechanical, thermal, and structural properties were evaluated. The addition of coconut fiber into starch/EVOH/glycerol blends reduced the ductile behavior of the matrix by making the composites more brittle. At low fiber content, blends were more flexible, with higher tensile strength than at higher fiber levels. The temperature at the maximum degradation rate slightly shifted to lower values as fiber content increased. Comparing blends with and without fibers, there was no drastic change in melt temperature of the matrix with increase of fiber content, indicating that fibers did not lead to significant changes in crystalline structure. The micrographs of the tensile fractured specimens showed a large number of holes resulting from fiber pull‐out from the matrix, indicating poor adhesion between fiber and matrix. Although starch alone degraded readily, starch/EVOH/glycerol blends exhibited much slower degradation in compost. Composites produced 24.4–28.8% less CO2 compared with starch in a closed‐circuit respirometer. Addition of increasing amount of fiber in starch/EVOH/glycerol composite had no impact on its biodegradation. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
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