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21.
P Casolo D Mosca C Amorotti B Drei A Raspadori P Di Blasio E Ganz G De Luca G Colli R De Maria D Amuso 《Canadian Metallurgical Quarterly》1997,68(2):207-11; discussion 212
Primary and sole breast lymphoma is a very rare disease. With the review of our series of 616 cases operated on for breast cancer, only 3 cases (0.48%) of primary breast non-Hodgkin lymphoma (LNH) have been observed. The authors outline the problems concerning diagnosis and therapy of this rare disease: pathological and immunohistochemical aspects are discussed. They stress the importance of staging in order to plan a correct multidisciplinary approach. 相似文献
22.
Anna‐Marja Aura Sirpa Karppinen Hannele Virtanen Pirkko Forssell Satu‐Maarit Heinonen Tarja Nurmi Herman Adlercreutz Kaisa Poutanen 《Journal of the science of food and agriculture》2005,85(12):2085-2093
Plant lignans are converted to mammalian forms, enterodiol and enterolactone, in the colon. Enhanced plasma or urinary enterolactone levels have been associated with lowered risk of cardiovascular diseases and breast cancer. Processed rye bran and its fractions were compared to ascertain the fermentation rates of fermentable carbohydrates and the bioconversion of lignans. Rye bran was extruded and treated with a food‐grade xylanase. Part of the xylanase‐treated rye bran was separated into a soluble rye bran extract and an insoluble residue, and a part of the xylanase‐treated rye bran was freeze‐dried without separation. All the samples were digested by pepsin and pancreatin and subsequently fermented with a human faecal inoculum in vitro. The consumption of carbohydrates, the productions of short‐chain fatty acids (SCFA), enterodiol and enterolactone were followed as a function of time. The soluble rye bran extract showed the fastest fermentation rate and the highest extent of fermentation determined as the consumption of neutral sugar residues (arabinose, xylose and glucose), the production of SCFA and the formation of enterodiol and enterolactone. Xylanase treatment enhanced the fermentation rate of extruded rye bran. An even a higher fermentation rate was observed for rye bran extract containing soluble carbohydrates. The amount of enterolactone precursors in rye seemed to be too low for enterolactone formation using an amount of substrate suitable for carbohydrate fermentation. However, xylanase treatment enhanced the availability of plant lignans from rye bran, as enterodiol formation was increased by the use of xylanase. Copyright © 2005 Society of Chemical Industry 相似文献
23.
A performance study of two onboard stored, baseband switched, TDMA satellites interconnected through intersatellite links is presented. The uplinks are operated under the slotted ALOHA policy, while the downlinks and intersatellite links are operated using TDM policy. Each satellite has a finite buffer capacity for successful packets arriving, on the uplinks and on the intersatellite links. The authors introduce an approximate analytical model that determines the satellite cluster performance in terms of mean delay, throughput, and overflow probability. The system performance is obtained as a function of the system load, traffic distribution, number of uplinks, number of buffers, number of Earth zones, number of transponders at each satellite, and the intersatellite link capacity. The analytical results were within the confidence intervals of the simulation results obtained with 99% confidence level. Using this model, the system designer can obtain the minimal system configuration for a required system performance 相似文献
24.
GG Schwartz MF Oliver MD Ezekowitz P Ganz D Waters JP Kane M Texter ML Pressler D Black BR Chaitman AG Olsson 《Canadian Metallurgical Quarterly》1998,81(5):578-581
Pediococcus sp. is a nonpathogenic heat-resistant spoilage organism that has been used as a test organism in milk pasteurization studies. These characteristics make this bacterium an attractive test organism to study the mode of bacterial thermal inactivation in a food pilot plant. We report here the effect of growth medium on the thermal D value of this organism in skim milk, whole liquid egg, 10% glucose solution, pineapple juice, apple juice, tomato juice, and water at 60 degrees C. Thermal inactivation was done in a submerged coil; D values were calculated from the linear portion of the survival curves by linear regression analysis. The range of D values of stationary-phase cells grown at 28 degrees C in tryptone glucose yeast extract (TGY) or tryptic soy broth (TSB) was 0.14 to 12.05 min in all heating menstrua tested. The TSB-grown cells exhibited the highest thermal resistance with skim milk and 10% glucose solution as the heating menstrua. Survival curves of the TGY-grown cells indicated the presence of a cell population heterogeneous in thermal resistance. The TSB-grown cells exhibited a cell population uniform in thermal resistance and with a lag time for thermal inactivation. When compared to TGY-grown cells, Pediococcus sp. grown in TSB showed a significant (P < 0.05) increase in D values by up to eightfold in all heating menstrua. Results from this study suggested that thermal inactivation of Pediococcus sp. was dependent on the growth medium and on the heating menstruum with respect to both pH and composition. 相似文献
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One of the major challenges in the virtual topology design of a WDM star based system, is to incorporate in the optimization process both realistic objective functions and real system behavior. The authors present an efficient discrete optimization algorithm that meets these goals while incorporating the prevailing traffic conditions. They simulate the real system and then approximate the objective function by a short term simulation. The optimization process is based on an ordinal optimization approach, i.e., is insensitive to the approximation of the objective function obtained by short term simulation. Another crucial issue in virtual topology design is how to evaluate the quality of the solution obtained by the algorithm. They propose a new metric to evaluate the solution quality, the so called suboptimal quality, obtained by deriving the solution's relative position in the state space according to the performance order. The experiments presented in the paper attest to the quality (efficiency and robustness) of the optimization algorithm and its suitability to solve the wavelength assignment problem 相似文献
28.
The efficiency of the M. E. Müller acetabular roof reinforcement ring is documented on 141 patients with 150 operated hips since 1976 with a minimal clinically and radiologically follow-up of 6 years. The metal backing of the cup prevented cranial migration and protrusion almost completely. After 1982, when a bone bank with frozen femoral heads was established, the loss of bone stock was replaced with allograft, which can be fixed sufficiently with the reinforcement ring. In revision arthroplasty with bone stock of poor quality and quantity the acetabular roof reinforcement ring is a good method to reconstruct the acetabulum. 相似文献
29.
Reports on 3 experiments, with 251 undergraduates, that examine serial position effects for rapidly-presented naturalistic scenes. The experiments provide a basis for comparison with the U-shaped serial position curve and list-length effect that typically result from verbal learning experiments. In contrast to the U-shaped verbal serial position function, results show a flat function at the beginning serial positions and a recency effect that is small and limited to the last serial position. There is also a set-size effect. Results suggest that the processing leading to a memory representation for visual stimuli such as pictures and linguistic stimuli such as words is qualitatively dissimilar. The findings can be accounted for by a serial processing model whose main parameter is the probability that the subject will switch attention from one picture to the next. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
30.
There has been an evolution in the AO/Association for the Study of Internal Fixation plating technique during the past 3 decades that includes the use of longer plates and fewer plate screws, fewer lag screws outside the plate, fewer unicortical screws at the plate periphery, and greater use of the 95 degrees blade plate to achieve balanced fixation of proximal and distal shaft fractures. These changes reflect an evolving technique of plate osteosynthesis that emphasizes indirect reduction techniques, biologic internal fixation, and improved biomechanics. Outcome data suggest that there has been an improvement with time that is reflected by shorter time to union, a decrease in the frequency of implant failures, delayed unions, nonunions, malunions, number of reoperations, and in overall rate of failure. The best predictor of success was the length of plate by logistic regression analysis. With the evolution of plating techniques and a greater emphasis on biology of fracture healing, the incidence of complications and failures has decreased after femoral shaft plating. Plate osteosynthesis of the femoral shaft is particularly advantageous in many situations and can be quite successful (87% success rate in Group III). 相似文献