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91.
L Domínguez Gadea L Díez C Lancha P Zurita M Mitjavila 《Canadian Metallurgical Quarterly》1993,192(9):428-430
It is described the case of a patient with Ovarian Cystadenoma in whom a 3.5 cm nodular lesion was accidentally detected in her left suprarenal gland. She had no signs of hypercortisolism or any other suprarenal pathology and was symptomless. Determinations in the urine of 24 hours of Cortisol, Adrenaline and Noradrenaline, 17-ketosteroids and Tetrahydroaldosterone were normal. Daily rhythm and plasmatic determinations of ACTH, cortisol and 11-deoxycortisol were normal. The Dexamethasone suppression test was also normal. In the suprarenal gammagraphy it appeared an intense captation by left suprarenal without visualization of right gland. A left suprarenalectomy was performed and the anatomopathological analysis showed a clear cell corticoadrenal adenoma. Therefore the only data of the function of suprarenal adenoma was the one coming from gammagraphy. We thought that the adenoma was responsible of practically all the corticoadrenal function without reaching pathological levels, meeting the criteria of "pre-Cushing" syndrome or subclinical Cushing, due to the fact that the contralateral gland was not seen in the gammagraphy. Therefore in the characterization of certain tumors which appear clinically and biochemically as non functional, the suprarenal gammagraphy could be a technique of great usefulness for the diagnosis. 相似文献
92.
93.
The study analyzes variables that influence the water management model based on a simultaneous relationship between competing demands in the Marina Baja of Alicante, using a methodology that directly links together urban and irrigation demands, making them relevant to each other from a socioeconomic point of view. The paper identifies the relevant variables of this model and the agent behaviour in a closed and joint system. It also aims to demonstrate that by considering water demands for different yet simultaneous uses and regarding clean and reclaimed waters as integrated resources, the system could remain in equilibrium without external water supplies. 相似文献
94.
José María Moreno-Jiménez Juan Aguarón Jesús Cardeñosa María Teresa Escobar José Luis Salazar Adrián Toncovich Alberto Turón 《Computers in human behavior》2012
Two key aspects of the Knowledge Society are the interconnection between the actors involved in the decision making processes and the importance of the human factor, particularly the citizen’s continuous learning and education. This paper presents a new module devoted to knowledge extraction and diffusion that has been incorporated into a previously developed decision making tool concerning the Internet and related with the multicriteria selection of a discrete number of alternatives (PRIOR-Web). Quantitative and qualitative procedures using data and text mining methods have been employed in the extraction of knowledge. Graphical visualisation tools have been incorporated in the diffusion stage of the methodological approach suggested when dealing with decision making in the Knowledge Society. The resulting collaborative platform is being used as the methodological support for the cognitive democracy known as e-cognocracy. 相似文献
95.
Juan L. Mata-Machuca Rafael Martínez-Guerra 《Computers & Mathematics with Applications》2012,63(6):1072-1078
In this paper we deal with the observer-based asymptotic synchronization problem for a class of chaotic oscillators. Some results based on a differential algebraic approach are used in order to determine the algebraic observability of unknown variables. The strategy consists of proposing a slave system (observer) which tends to follow asymptotically the master system. The methodology is tested in the real-time asymptotic synchronization of the Colpitts oscillator by means of a proportional reduced order observer (PROO) of free-model type. 相似文献
96.
97.
We have found experimentally that rf SQUID's working in a nonhysteretic mode with small critical currents give exactly at resonance and at very low rf bias a triangular pattern with a period equal to half of one elementary quantum of magnetic flux. We discuss a possible explanation of this peculiar result. 相似文献
98.
G. Morell A. González-Berríos B. R. Weiner S. Gupta 《Journal of Materials Science: Materials in Electronics》2006,17(6):443-451
The synthesis and properties of sulfur-doped nanocrystalline diamond films were investigated. The films were deposited by
hot-filament chemical vapor deposition on Mo substrates using methane, hydrogen, and hydrogen disulfide. The nanocrystalline
nature of the material arises from the induction of continuous secondary nucleation in the chemical vapor deposition environment.
Complementary characterization tools were employed in order to obtain a comprehensive and coherent understanding of the correlations
between the structural and electronic properties. In particular, sulfur-doped nanocrystalline diamond films show n-type Hall
conductivity, enhanced field emission properties, and insensitivity to ion radiation. It was found that n-type doping of the
tetragonally-bonded carbon matrix together with a nano network of trigonally-bonded carbon are crucial elements for enhanced
field emission from nanocrystalline diamond. These conclusions and the corresponding supporting evidence are discussed. 相似文献
99.
Mauricio Areiza-Hurtado Carlos Vega-Posada J. Darío Aristizábal-Ochoa 《Canadian Metallurgical Quarterly》2005,131(7):752-762
The second-order stiffness matrix and corresponding loading vector of a prismatic beam–column subjected to a constant axial load and supported on a uniformly distributed elastic foundation (Winkler type) along its span with its ends connected to elastic supports are derived in a classical manner. The stiffness coefficients are expressed in terms of the ballast coefficient of the elastic foundation, applied axial load, support conditions, bending, and shear deformations. These individual parameters may be dropped when the appropriate effect is not considered; therefore, the proposed model captures all the different models of beams and beam–columns including those based on the theories of Bernoulli–Euler, Timoshenko, Rayleigh, and bending and shear.The expressions developed for the load vector are also general for any type or combinations of transverse loads including concentrated and partially nonuniform distributed loads. In addition, the transfer equations necessary to determine the transverse deflections, rotations, shear, and bending moments along the member are also developed and presented. 相似文献
100.
This study examined the mediating role of service climate in the prediction of employee performance and customer loyalty. Contact employees (N=342) from 114 service units (58 hotel front desks and 56 restaurants) provided information about organizational resources, engagement, and service climate. Furthermore, customers (N=1,140) from these units provided information on employee performance and customer loyalty. Structural equation modeling analyses were consistent with a full mediation model in which organizational resources and work engagement predict service climate, which in turn predicts employee performance and then customer loyalty. Further analyses revealed a potential reciprocal effect between service climate and customer loyalty. Implications of the study are discussed, together with limitations and suggestions for future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献