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BACKGROUND: Both fibroblast-mediated cytokine gene therapy and bone marrow transplantation (BMT) have proven to be efficient protocols for the recovery of bone marrow depression. In this report, the effects of fibroblast-mediated interleukin (IL)-6 gene therapy, in combination with BMT, on the recovery of irradiation-induced bone marrow depression were investigated. METHODS: NIH3T3 fibroblast cells engineered to secrete IL-6 (NIH3T3-IL-6) or NIH3T3 cells transduced with the neomycin gene (NIH3T3-Neo), in combination with 10(7), 10(6), or 10(5) syngeneic bone marrow cells, were implanted into irradiated mice. RESULTS: The platelets and white blood cells in the peripheral blood of the irradiated mice increased greatly 12 days after implantation of NIH3T3-IL-6 cells and BMT, the white blood cell counts were restored to a normal level 32 days after the combined therapy, and the platelet number was obviously higher than that in mice implanted with NIH3T3-Neo and BMT. Twenty and 25 days after the combined therapy, the mice showed accelerated recovery of colony-forming unit (CFU)-granulocyte/macrophages and CFU-megakaryocytes when compared with the mice implanted with NIH3T3-Neo cells and BMT. Ten days after lethal irradiation with gamma rays, the spleens formed more CFU-spleen in mice implanted with NIH3T3-IL-6 cells and BMT than in mice injected with phosphate-buffered saline or NIH3T3-Neo cells. Combined therapy with NIH3T3-IL-6 cell implantation and BMT delayed the survival period of the hematopoietic-depressed mice significantly when compared with therapy with NIH3T3-Neo cell implantation and BMT. CONCLUSIONS: These data demonstrated that the combined therapy of fibroblast-mediated IL-6 gene therapy and BMT could significantly promote the recovery of irradiation-induced hematopoietic depression.  相似文献   
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A drawback of structured prediction methods is that parameter estimation requires repeated inference, which is intractable for general structures. In this paper, we present an approximate training algorithm called piecewise training (PW) that divides the factors into tractable subgraphs, which we call pieces, that are trained independently. Piecewise training can be interpreted as approximating the exact likelihood using belief propagation, and different ways of making this interpretation yield different insights into the method. We also present an extension to piecewise training, called piecewise pseudolikelihood (PWPL), designed for when variables have large cardinality. On several real-world natural language processing tasks, piecewise training performs superior to Besag’s pseudolikelihood and sometimes comparably to exact maximum likelihood. In addition, PWPL performs similarly to PW and superior to standard pseudolikelihood, but is five to ten times more computationally efficient than batch maximum likelihood training.  相似文献   
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Speech Recognition is frequently cited as a potential remedy to distraction resulting from drivers' operation of in-vehicle devices. This position typically assumes that the introduction of speech recognition will result in reduced cognitive workload and improved driving performance. Past research neither fully supports nor fully discounts this assumption. However, it is difficult to compare many of these studies, due to differences in device operation tasks, the pacing of those tasks, speech recognition system performance, and system interface designs. In an effort to directly address the effect of voice recognition on driver distraction, the present authors developed a capability to manipulate the performance characteristics of a speech recognition system through a Wizard of Oz speech recognition system and installed this system in a simulated driving environment. The sensitivity of the simulated driving environment and speech recognition accuracy manipulation were evaluated in an initial study comparing driver cognitive workload and driving performance during self-paced simulated operation of a personal digital assistant (PDA) during no PDA use, manual control of the PDA, and speech control of the PDA. In the Speech PDA condition, speech recognition accuracy was varied between drivers. Analysis of drivers' emergency braking response times and rated cognitive workload revealed significantly lower cognitive demand and better performance in the No PDA condition when compared to the Manual PDA condition. The Speech PDA condition resulted in response times and rated cognitive workload levels that were between the No PDA and Manual PDA conditions, but not significantly different from either of these conditions. Further analysis of emergency braking performance revealed a non-significant trend towards better performance in conjunction with higher speech recognition accuracy levels. The potential for reducing driver distraction through the careful development and evaluation of speech recognition systems is discussed.  相似文献   
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It is shown that the discriminant of the discriminant of a multivariate polynomial has the same irreducible factors as the product of seven polynomials each of which is defined as the GCD of the generators of an elimination ideal. Under relatively mild conditions of genericity, three of these polynomials are irreducible and generate the corresponding elimination ideals, while the other four are equal to one. Moreover the irreducible factors of two of these polynomials have multiplicity at least two in the iterated discriminant and the irreducible factors of two others of the seven polynomials have multiplicity at least three.  相似文献   
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Libraries' most central and costly activity-cataloging material and maintaining the catalogs providing end-user access-had requirements that defied efficient automation until the mid-1960s, when the Library of Congress developed the MARC format for data records. The format became the foundation for automated systems for libraries that took data sharing to new levels and enabled exploitation of future computer developments to create today's online catalog environment. This article describes the complexity of the library application, how the MARC format was innovative, and why it was the foundation of automated systems development in libraries  相似文献   
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It is difficult to treat the intra-articular fracture of distal tibia or Pilion's fracture. From 1987 to 1995, 43 cases of Pilon's fracture were admitted and treated with different methods. After treatment, they had been followed up for 1 to 8 years. According to Riiedi's Classification, there were type I 12 cases, type II 21 cases and type III 10 cases. The methods used on these patients included manual reduction and plaster of paris immobilization, calcaneous tubercle traction and plaster of paris immobilization, open reduction and internal fixation with Kirschner wires, and open reduction and internal fixation with AO plate. The outcome was evaluated according to Ovadia's criteria, for type I fracture, 8 cases were treated with conservative method with a satisfactory rate of 79.17% and 4 cases were treated with operation with a satisfactory rate of 91.67%; for type II, conservative method for 12 cases and the satisfactory rate was 33.33%, and operation for 9 cases with a satisfactory rate of 70.37%; for type III, conservative method for 2 cases, with poor result, and operation for 8 cases with satisfactory rate of 79.17%. The indication for conservative treatment was type I fracture. It showed that for Pilon's fracture, the outcome of open reduction and internal fixation was superior to that of the conservative treatment, especially in those having internal fixation with AO plate.  相似文献   
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Two stress and illness models that included the joint mediating effects of health practices and hardiness were tested prospectively over a 2-mo period. 86 undergraduates completed 5 subscales indexing hardiness. Stress, health practices, and illness for the prior month were assessed at this time as well as 1 and 2 mo later. In the 1st model, illness was measured by the severity of physical symptoms. In the 2nd model, it was measured by the number of symptoms reported. In both models, path analyses revealed that stress acted directly to affect illness as well as indirectly by changing health practices. Hardiness also had a direct effect on illness as well as an indirect effect through health practices. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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