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121.
Comparative B‐mode and Doppler renal ultrasonography with histopathological findings in dogs positive for canine visceral leishmaniasis
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Pollyana Irene Baltazar Laecio Da Silva Moura Gerson Tavares Pessoa Renan Paraguassu De Sá Rodrigues Marina Pinto Sanches Anaemilia Das Neves Diniz Francisco Das Chagas Araújo Sousa Porfírio Candanedo Guerra Willams Costa Neves Robson Fortes Giglio Jacyara De Jesus Rosa Pereira Alves Francisco De Assis Leite Souza Juliana Fortes Vilarinho Braga Flávio Ribeiro Alves 《Microscopy research and technique》2016,79(7):637-645
Morphological parameters and renal flow were assessed and measured in six clinically healthy dogs with negative serological and parasitological examinations for canine visceral leishmaniasis (CVL) and six dogs with CVL‐positive serological and parasitological tests and asymptomatic condition of the disease. Kidney length and diameter were measured and compared with the aorta/kidney ratio. Alterations in flow were measured using the flow velocity (cm/s) and resistance index (RI). Renal function was assessed by serum biochemical examination (urea, creatine, total proteins, albumin, and globulin) and urinalysis. CVL‐positive animals presented heterogeneous kidney echotexture, reduced vascular flow, hypoperfusion, lesser visualization of the arcuate arteries, high RI values (1.06 ± 0.28 for the right kidney and 1.10 ± 0.30 for the left kidney), reduced diastolic flow, and high systolic peak. They also presented positive creatine/RI correlation and between the renal artery vascular flow and kidney diameter. Histopathological analysis of CVL‐positive animals was compatible and confirmed hemodynamic changes observed by Doppler ultrasound. The findings in the present study showed that Doppler ultrasonography is a valid method to assess and detect alterations in flow in renal pathological processes with kidney vascular damage, as in the case of leishmaniasis, and can help in the diagnosis of animals with this infection. Microsc. Res. Tech. 79:637–645, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
122.
Luis Esteva Orlando Javier Díaz-López Alberto Vásquez Jesus Alberto León 《Structure and Infrastructure Engineering》2016,12(7):848-860
Seismic reliability and expected performance functions of structural systems are sensitive to the process of damage accumulation associated with the random sequences of ground motion excitations that those systems may experience. Optimum life cycle-based engineering decisions must examine the influence of concepts related to both the target safety level of the initial system and the eventual repair and maintenance actions that may be undertaken during the life of the system. This study includes an overview of the general framework supporting these decisions as well as some available results about (a) the influence of damage accumulation of the seismic vulnerability functions of building structures, (b) approximate estimates of accumulated damage and (c) optimum damage threshold values for repair of structural frames or replacement of energy dissipating devices. Some comments are presented concerning desirable studies about life cycle optimisation of systems exposed to different types of excitations. 相似文献
123.
Jesus E. Molinar-Solis Felipe Gomez-Castaneda Jose A. Moreno-Cadenas Victor H. Ponce-Ponce 《The Journal of VLSI Signal Processing》2007,49(1):207-216
At present, the Cellular Neural Network (CNN) is a potential parallel structure able to perform image processing tasks in
real-time when is effectively implemented in CMOS technology. The CNN silicon integration success is due mainly to the local
connectivity of processing cells. In this work, an alternative design based on floating-gate MOS inverters is presented, which
uses unipolar signals for solving binary tasks. The approach brings a fast response in a reduced silicon area, as shown through
electrical simulations. A prototype cell in CMOS technology (AMI, 1.2 micron) was fabricated and tested for eight image processing
tasks.
相似文献
Victor H. Ponce-Ponce |
124.
Desorption electrospray ionization mass spectrometry (DESI MS) is rapidly becoming accepted as a powerful surface characterization tool for a wide variety of samples in the open air. Besides its well-established high-throughput capabilities, a unique feature of DESI is that chemical reactions between the charged spray microdroplets and surface molecules can be exploited to enhance ionization. Here, we present a rapid screening assay for artesunate antimalarials based on reactive DESI. Artesunate is a vital therapy for Plasmodium falciparum malaria, but artesunate tablets have been counterfeited on a very large scale in SE Asia, and more recently in Africa. For this reason, faster and more sensitive screening tests are urgently needed. The proposed DESI assay is based on the formation of stable noncovalent complexes between linear alkylamines dissolved in the DESI spray solution and artesunate molecules exposed on the tablet surface. We found that, depending on amine type and concentration, a sensitivity gain of up to 170x can be obtained, in comparison to reagent-less DESI. Hexylamine (Hex), dodecylamine (DDA), and octadecylamine (ODA) produced proton-bound noncovalent complexes with gas-phase stabilities, increasing in the order [M + Hex + H]+ < [M + DDA + H]+ < [M + ODA + H]+. Tandem MS experiments revealed that complex formation occurred by hydrogen bonding between the amine nitrogen and the ether-like moieties within the artesunate lactone ring. After the reactive DESI assay was fully characterized, it was applied to a set of recently collected suspicious artesunate tablets purchased in shops and pharmacies in SE Asia. Not only did we find that these samples were counterfeits, but we also detected the presence of several wrong active ingredients. Of particular concern was the positive detection of artesunate traces in the surface of one of the samples, which we quantified with standard chromatographic techniques. 相似文献
125.
Jesus Gonzalez-Trejo Jose Alvarez Ramirez Guillermo Fernandez 《Journal of Process Control》1999,9(3):221-231
The goal of this paper is to describe a linearizing feedback adaptive control structure which leads to a high quality regulation of the output error in the presence of uncertainties and external disturbances. The controller consists of three elements: a nominal input–output linearizing compensator, a state observer and an uncertainty estimator, which provides the adaptive part of the control structure. In this way, the feedback controller, based on the disturbance observer, compensates for external disturbances and plant uncertainties. The effectiveness of the controller is demonstrated on a distillation column via numerical simulations. © 相似文献
126.
Jesus Beltran‐Heredia Joaquin Torregrosa Joaquin R Dominguez Juan Garcia 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2000,75(7):561-568
The present work is a study of oxidative degradation of the organic matter present in the washing waters from the black‐table‐olive industry. This oxidation is performed by an ozonation process, by an aerobic biological degradation process, and by another ozonation of biologically pretreated washing waters. In the ozonation process, a second‐order kinetic reaction with respect to ozone and COD or aromaticity has been deduced. The kinetic rate constants were correlated as a function of temperature by Arrhenius‐type equations. In the aerobic biological treatment, a kinetic study was performed using the Contois model, giving a value of 4.8 10−2 h−1 for the kinetic bioreaction constant. Likewise, a cell yield coefficient of 0.30 g VSS g COD−1 and a kinetic constant for the endogenous metabolisme of 1.2 10−2 h−1 were deduced. Finally, in the ozonation of biologically pretreated wash‐waters, the deduced kinetic rate constants for COD and aromaticity were, respectively, 4.5 and 2.4 times higher that those corresponding to the ozonation of wash‐waters without biological pretreatment. © 2000 Society of Chemical Industry 相似文献
127.
F Javier Benitez Jesus Beltran‐Heredia Joaquin Torregrosa Juan L Acero 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1999,74(7):639-646
The degradation of the pollutant organic matter present in olive oil mill wastewaters (OMW) is carried out by a single ozonation, a single aerobic degradation, and the combination of two successives steps: an ozonation followed by an aerobic degradation, and an aerobic degradation followed by an ozonation. In both single processes, the removal of this contaminant load is followed by means of global parameters which are directly related to the concentration of organic compounds in those effluents: chemical oxygen demand and total aromatic and phenolic contents. In the ozonation, an approximate kinetic study is performed which leads to the evaluation of the apparent kinetic constants for the aromatic reduction, kA. In the aerobic degradation, the kinetic study is conducted by using the Grau model, which is applied to the experimental data, and leads to the determination of the kinetic parameters of this model, K2 and n. In the combined processes, a higher COD global reduction is obtained by the successive stages, and an improvement in the removal of the organic material during the second treatment of both processes due to the pretreatment conducted is also observed. This enhancement is shown by an increase of the kinetic parameters (K2 and n in the aerobic degradation of the pre‐ozonated wastewaters; the apparent constant kA in the ozonation of the wastewaters preliminary fermented aerobically), in relation to the values obtained for them in the single processes carried out at the same operating conditions. © 1999 Society of Chemical Industry 相似文献
128.
Maria D Guilln Nerea Cabo and Jesus Burillo 《Journal of the science of food and agriculture》1996,70(3):359-363
The compositions of the essential oils of Rosmarinus officinalis L, Salvia lavandulifolia V and Lavandula latifolia M, obtained by steam distillation from plants cultivated in the northeast of Spain, have been studied by gas chromatography and gas chromatography/mass spectrometry. The essential oil of rosemary appears to be more complex and richer in flavour notes than other previously studied Spanish rosemary oils, and has an intermediate ratio of α-pinene and of 1,8-cineole in relation to essential oils of rosemary of different geographical origins, but higher proportions of camphor, verbenone and linalool. The essential oil of sage has proportions of 1,8-cineole, camphor, endo-borneol, trans-caryophyllene and α-humulene closer to commercial Salvia officinalis L than to other Spanish sages of different geographical locations, and the difference from commercial Salvia officinalis L is due principally to the higher ratio of terpene hydrocarbons and the lower proportion of thujone in the Spanish sage studied here. The essential oil of the spike lavender has the same main components and similar proportions as other Spanish wild and commercial spike lavender essen-tial oils, but shows differences in the nature of the minor components (rhodinol fraction). 相似文献
129.
130.
Singh Y Dolphin GT Razkin J Dumy P 《Chembiochem : a European journal of chemical biology》2006,7(9):1298-1314
The creation of molecular systems that can mimic some of the properties of natural macromolecules is one of the major endeavors in contemporary protein chemistry. However, the construction of artificial proteins with predetermined structure and function is difficult on account of complex folding pathways. The use of topological peptide templates has been suggested to induce and stabilize defined secondary and tertiary structures. This is because the recent advances in the chemistry of coupling reagents, protecting groups, and solid-phase synthesis have made the chemical synthesis of peptides with conformationally controlled and complex structures feasible. Besides their use as structure-inducing devices, these peptide templates can also be utilized to construct novel structures with tailor-made functions. Herein, we present recent advances in the field of peptide-template-based approaches with particular emphasis on the demonstrated utility of this approach in molecular recognition, along with related applications. 相似文献