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排序方式: 共有6407条查询结果,搜索用时 31 毫秒
61.
RM Mu?oz LA Pulpón M Yebra J Segovia M San Martín C Salas 《Canadian Metallurgical Quarterly》1998,17(11):801-806
The fibrinolytic capacity of patients with acute myocardial infarction (AMI) is known to be impaired. The primary regulatory element of the fibrinolytic system is plasminogen activator inhibitor (PAI). It has been previously observed that there are 2 peaks in the plasma PAI level of AMI patients at 4h and 16h after thrombolytic therapy with recombinant tissue plasminogen activator (rtPA). Lanoteplase/SUN9216 is a mutant tPA with a biological half-life longer than that of rtPA. Thrombolytic therapy with mutant tPA or rtPA was carried out consecutively in 21 patients with AMI (8 patients as the mutant tPA group, and 13 patients as the rtPA group). The recanalization time of the mutant tPA group was significantly faster than that of the rtPA group (16.1 +/- 3.9 min vs 39.6 +/- 4.8 min, p<0.01). The PAI activity at 4h after the initiation of thrombolysis was significantly lower in the mutant tPA group than in the rtPA group (8.74 +/- 5.46IU/L vs 26.74 +/- 3.35 IU/L, p<0.01). There was a one mild peak in serial plasma PAI activity levels 24h after the initiation of thrombolysis. The results suggest that thrombolytic therapy with mutant tPA reduced the impairment of fibrinolytic capacity. The mutant tPA gives faster recanalization and lower PAI activity after successful thrombolysis, compared with rtPA. 相似文献
62.
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64.
This study was designed to examine whether cyclosporine (CyA) acts on the endocrine system by modifying the pulsatile secretion pattern of prolactin and LH. Both pituitary-grafted and sham-operated rats were submitted to a subcutaneous vehicle or CyA (5 mg/kg) treatment daily for 10 days beginning on the day of surgery. Pituitary grafting and/or CyA administration changed the pulsatile pattern of prolactin observed in sham-operated animals. The mean values of serum prolactin were significantly increased by pituitary grafting and the treatment with CyA further increased them. The mean half-life of prolactin was significantly increased in pituitary-grafted rats and was not changed by CyA administration, although it was decreased in sham-operated rats. The frequency of prolactin pulses was significantly decreased in pituitary-grafted as compared to sham-operated controls and was not further modified by CyA administration. However, in sham-operated rats a significant decrease of this parameter was observed. Duration of the prolactin peaks was significantly increased by pituitary grafting, and was not modified by CyA administration in any of the groups studied. The absolute amplitude of the prolactin peaks was significantly increased in pituitary-grafted as compared to sham-operated animals, and the treatment with CyA further increased this parameter in both groups. Mean values of LH were significantly increased in pituitary-grafted as compared to control rats. CyA administration significantly increased LH levels in sham-operated rats and decreased them in pituitary-grafted animals. The mean half-life, the pulse frequency and the duration of LH peaks were not modified by either pituitary grafting or CyA administration.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
65.
The aim of this study is to answer the question of whether improvements in the health of the elderly in European countries could compensate for population ageing on the supply side of the labour market. We propose a state-of-health-specific (additive) decomposition of the old-age dependency ratio into an old-age healthy dependency ratio and an old-age unhealthy dependency ratio in order to participate in a discussion of the significance of changes in population health to compensate for the ageing of the labour force. Applying the proposed indicators to the Eurostat's population projection for the years 2010-2050, and assuming there will be equal improvements in life expectancy and healthy life expectancy at birth, we discuss various scenarios concerning future of the European labour force. While improvements in population health are anticipated during the years 2010-2050, the growth in the number of elderly people in Europe may be expected to lead to a rise in both healthy and unhealthy dependency ratios. The healthy dependency ratio is, however, projected to make up the greater part of the old-age dependency ratio. In the European countries in 2006, the value of the old-age dependency ratio was 25. But in the year 2050, with a positive migration balance over the years 2010-2050, there would be 18 elderly people in poor health plus 34 in good health per 100 people in the current working age range of 15-64. In the scenarios developed in this study, we demonstrate that improvements in health and progress in preventing disability will not, by themselves, compensate for the ageing of the workforce. However, coupled with a positive migration balance, at the level and with the age structure assumed in the Eurostat's population projections, these developments could ease the effect of population ageing on the supply side of the European labour market. 相似文献
66.
López-Robles J. R. Cobo M. J. Gutiérrez-Salcedo M. Martínez-Sánchez M. A. Gamboa-Rosales N. K. Herrera-Viedma E. 《Applied Intelligence》2021,51(9):6547-6568
Applied Intelligence - Applied Intelligence is one of the most important international scientific journals in the field of artificial intelligence. From 1991, Applied Intelligence has been oriented... 相似文献
67.
Palomares Iván Martínez-Cámara Eugenio Montes Rosana García-Moral Pablo Chiachio Manuel Chiachio Juan Alonso Sergio Melero Francisco J. Molina Daniel Fernández Bárbara Moral Cristina Marchena Rosario de Vargas Javier Pérez Herrera Francisco 《Applied Intelligence》2021,51(9):6497-6527
Applied Intelligence - The17 Sustainable Development Goals (SDGs) established by the United Nations Agenda 2030 constitute a global blueprint agenda and instrument for peace and prosperity... 相似文献
68.
The HaLoop approach to large-scale iterative data analysis 总被引:1,自引:0,他引:1
Yingyi Bu Bill Howe Magdalena Balazinska Michael D. Ernst 《The VLDB Journal The International Journal on Very Large Data Bases》2012,21(2):169-190
The growing demand for large-scale data mining and data analysis applications has led both industry and academia to design
new types of highly scalable data-intensive computing platforms. MapReduce has enjoyed particular success. However, MapReduce
lacks built-in support for iterative programs, which arise naturally in many applications including data mining, web ranking,
graph analysis, and model fitting. This paper (This is an extended version of the VLDB 2010 paper “HaLoop: Efficient Iterative
Data Processing on Large Clusters” PVLDB 3(1):285–296, 2010.) presents HaLoop, a modified version of the Hadoop MapReduce framework, that is designed to serve these applications. HaLoop
allows iterative applications to be assembled from existing Hadoop programs without modification, and significantly improves
their efficiency by providing inter-iteration caching mechanisms and a loop-aware scheduler to exploit these caches. HaLoop
retains the fault-tolerance properties of MapReduce through automatic cache recovery and task re-execution. We evaluated HaLoop
on a variety of real applications and real datasets. Compared with Hadoop, on average, HaLoop improved runtimes by a factor
of 1.85 and shuffled only 4 % as much data between mappers and reducers in the applications that we tested. 相似文献
69.
José M. Cecilia José M. García Ginés D. Guerrero Miguel A. Martínez-del-Amor Mario J. Pérez-Jiménez Manuel Ujaldón 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(2):231-246
Membrane Computing is a discipline aiming to abstract formal computing models, called membrane systems or P systems, from the structure and functioning of the living cells as well as from the cooperation of cells in tissues, organs, and
other higher order structures. This framework provides polynomial time solutions to NP-complete problems by trading space
for time, and whose efficient simulation poses challenges in three different aspects: an intrinsic massively parallelism of
P systems, an exponential computational workspace, and a non-intensive floating point nature. In this paper, we analyze the
simulation of a family of recognizer P systems with active membranes that solves the Satisfiability problem in linear time
on different instances of Graphics Processing Units (GPUs). For an efficient handling of the exponential workspace created
by the P systems computation, we enable different data policies to increase memory bandwidth and exploit data locality through
tiling and dynamic queues. Parallelism inherent to the target P system is also managed to demonstrate that GPUs offer a valid
alternative for high-performance computing at a considerably lower cost. Furthermore, scalability is demonstrated on the way
to the largest problem size we were able to run, and considering the new hardware generation from Nvidia, Fermi, for a total
speed-up exceeding four orders of magnitude when running our simulations on the Tesla S2050 server. 相似文献
70.
J. M. Martínez 《Computing》1987,39(4):307-325
We introduce a new method for solving Nonlinear Least Squares problems when the Jacobian matrix of the system is large and sparse. The main features of the new method are the following:
- The Gauss-Newton equation is “partially” solved at each iteration using a preconditioned Conjugate Gradient algorithm.
- The new point is obtained using a two-dimensional trust region scheme, similar to the one introduced by Bulteau and Vial.