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991.
992.
The morphology of the pineal gland of the yellow‐toothed cavy (Galea Spixii Wagler, 1831) and red‐rumped agouti (Dasyprocta leporina linnaeus, 1758) 下载免费PDF全文
Felipe Venceslau Câmara Igor Renno Guimarães Lopes Gleidson Benevides de Oliveira Ferdinando Vinicius Fernandes Bezerra Radan Elvis Matias de Oliveira Carlos Magno Oliveira Júnior Alexandre Rodrigues Silva Moacir Franco de Oliveira 《Microscopy research and technique》2015,78(8):660-666
The pineal gland is an endocrine gland found in all mammals. This article describes the morphology of this important gland in two species of Caviideae, namely the yellow‐toothed cavy and the red‐rumped agouti. Ten adult animals of the two species used in current analysis were retrieved from the Center for the Multiplication of Wild Animals (CEMAS/UFERSA) and euthanized. The glands were removed and photographed in situ and ex situ. They were fixed in a paraformaldehyde solution 4% or glutaraldehyde 2.5% solution and submitted to routine histological techniques respectively for light and scanning electron microscopy. Macroscopically, the pineal gland with its elongated structure may be found between the cerebral hemispheres facing the rostral colliculi. Microscopically, pinealocytes and some glia cells were predominant. Contrastingly, to the cavy's pineal gland, a capsule covered the organ in the agouti, with the emission of incomplete septa to the interior, which divided it into two lobules. Light and scanning electron microscopes failed to show calcareous concretions in the pineal gland. Based on the topography of the cavy's and agouti's pineal gland, it may be classified as supra‐callosum and ABC type. Microsc. Res. Tech. 78:660–666, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
993.
Sudhanshu Tyagi Sudeep Tanwar Sumit Kumar Gupta Neeraj Kumar Joel J.P.C.Rodrigues 《中兴通讯技术(英文版)》2014,(3):22-29
Over the past few decades, there has been a revolution in ICT, and this has led to the evolution of wireless sensor networks(WSN), in particular, wireless body area networks. Such networks comprise a specialized collection of sensor nodes(SNs) that may be deployed randomly in a body area network to collect data from the human body. In a health monitoring system, it may be essential to maintain constant environmental conditions within a specific area in the hospital. In this paper, we propose a temperature-monitoring system and describe a case study of a health-monitoring system for patents critically ill with the same disease and in the same environment. We propose Enhanced LEACH Selective Cluster(E-LEACH-SC) routing protocol for monitoring the temperature of an area in a hospital. We modified existing Selective Cluster LEACH protocol by using a fixed-distance-based threshold to divide the coverage region in two subregions. Direct data transmission and selective cluster-based data transmission approaches were used to provide short-range and long-distance coverage for the collection of data from the body of ill patients. Extensive simulations were run by varying the ratio of node densities of the two subregions in the health-monitoring system. Last Node Alive(LNA), which is a measure of network lifespan, was the parameter for evaluating the performance of the proposed scheme. The simulation results show that the proposed scheme significantly increases network lifespan compared with traditional LEACH and LEACH-SC protocols, which by themselves improve the overall performance of the health-monitoring system. 相似文献
994.
Francisca Rodrigues Maria João Maia José das Neves Bruno Sarmento Maria Helena Amaral Maria Beatriz P.P. Oliveira 《Drug development and industrial pharmacy》2015,41(9):1518-1525
Objective: The aim of this study was to develop and characterize suppositories for vaginal delivery of Lactobacillus acidophilus.Methods: Formulations were performed in order to select suitable excipients based on suppository formation feasibility and cytotoxicity. Solid body and hollow-type suppositories were prepared by melting and molding using poly(ethylene glycol) (PEG) 400 and 4000 or Witepsol (WIT) H12 as excipients. L. acidophilus was incorporated in the molten mass before molding solid body suppositories or added as suspension into the cavity of hollow-type suppositories and sealed molten excipients. Cytotoxicity of the selected excipients was evaluated by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium and lactate dehydrogenase assays against VK2/E6E7, HEC-1-A and HeLa cells. Suppositories were characterized regarding organoleptic characteristics, mass uniformity, disintegration, breaking strength and L. acidophilus in vitro release.Results: PEG 400, PEG 4000 and WIT H12 showed the absence of toxicity when tested using three different vaginal cell lines. Obtained vaginal suppositories presented uniform and mild texture, a content of about 1?×?108 colony-forming units, completely disintegrated in simulated vaginal environment in less than 60?min and provided sustained in vitro release of L. acidophilus. Release studies further demonstrated that incorporation of freeze-dried bacteria did not result in significant loss of viable bacteria, thus supporting that vaginal suppositories may possess good properties to promote the replacement of the vaginal flora in situations of urinary tract infection.Conclusion: Hollow-type suppositories showed to be promising delivery vehicles for vaginal delivery of probiotics. 相似文献
995.
A. S. Fragoso M. B. Silva C. P. de Melo J. L. A. Aguiar C. G. Rodrigues P. L. de Medeiros J. F. Branco Junior C. A. S. Andrade M. D. L. Oliveira 《Journal of materials science. Materials in medicine》2014,25(1):229-237
It is of current interest the identification of appropriate matrices for growing mesenchymal stem cells (MSC). These cells are able not only to regenerate themselves but also to differentiate into other type of functional cells, and so they have been extensively used in tissue engineering. In this work, we have evaluated the use of electric impedance spectroscopy (EIS) to follow the adhesion of MSC from Wharton’s jelly of the human umbilical cord (hWJMSC) on sugarcane biopolymers (SCB). Impedance spectra of the systems were obtained in the frequency range of 102–105 Hz. An EIS investigation showed that when deposited on a metallic electrode SCB films prevent the passage of electrons between the solution and the metallic interface. The impedance spectra of hWJMSCs adhered on SCB revealed that there is a significant increase in the magnitude of the impedance when compared to that of pure SCB. The corresponding resistance (real part of the impedance) was even higher for the SCB–hWJMSC system than for SCB without cells on their surface, in an indication of an increased blockage to the electron transfers. The resistance charge transfer is extracted by curve-fitting the impedance spectra to an equivalent circuit model. Also, a shift of the phase angle to higher frequencies was obtained for SCB–hWJMSC system as a result from hWJMSC adhesion. Our study demonstrates that EIS is an appropriate method to evaluate the adhesion of MSC. SCB can be considered as a promising biomaterial for tissue engineering. 相似文献
996.
In this paper, we study dynamical systems of product type and some particular inducing scheme motivated by neural dynamics (called avalanche transformation). We derive the distribution of avalanche sizes and give sufficient conditions such that the avalanche transformation is ergodic. Moreover, we deduce a multivariate central limit theorem as a corollary.
In memoriam: Wenbo V. Li (1963–2013) 相似文献
997.
M. Fernanda S. Rodrigues J. M. Cardoso Teixeira J. Claudino P. Cardoso A. J. Batel Anjos 《Civil Engineering and Environmental Systems》2013,30(1):26-39
An evaluation methodology to estimate the envelope's degradation level (DL) of social housing buildings was developed. The DL of each of the principal faults was determined as well as the building envelope's evaluation index (EI). Degradation assessment results were obtained through visual survey and were aggregated by a method developed in the research. With the aim of discovering the visual phenomena's underlying mechanism, models have been constructed to analyse the behaviour of each dependent variable (faults), according to the independent ones: building age, covering type, last repair action and proximity to sea, trees, main roads, industrial zones and collective buildings. After obtaining the building's EI, models were developed to estimate the influence of the predictor variables in this index. The aim of this paper is to present the models for obtaining the envelope EI of a set of social residence buildings in Aveiro District, Portugal. This was achieved in the scope of a research project on prioritising refurbishment interventions in the Portuguese social housing stock [Rodrigues, M.F.S., 2008. Social Housing Conservation State. Evaluation index and methodology. PhD Thesis, Universidade de Aveiro, Aveiro (in Portuguese)]. 相似文献
998.
Jacques Wainer Claudia G. Novoa Barsottini Danilo Lacerda Leandro Rodrigues Magalhães de Marco 《Information and Software Technology》2009,51(6):1081-1085
This paper repeats part of the analysis performed in the 1995 paper “Experimental evaluation in Computer Science: a quantitative study” by Tichy and collaborators, for 147 papers randomly selected from the ACM, published in the year 2005. The papers published in 2005 are classified in the following way: 4% theory, 17% empirical, 4.7% hypothesis testing, 3.4% other, and 70% design and modeling (using the 1995 paper categories). Within the design and modeling class, 33% of the papers have no evaluation. The numbers of the 2005 sample are very similar to the original figures for the 1995 sample, which shows that Computer Science research has not increased significantly its empirical or experimental component. 相似文献
999.
Alexandre Baratella Lugli Max Mauro Dias Santos Lucia Regina Horta Rodrigues Franco 《ISA transactions》2009,48(2):228-236
This paper presents a computer tool to support in the project and development of an industrial Ethernet network, verifying the physical layer (cables-resistance and capacitance, scan time, network power supply-POE’s concept ”Power Over Ethernet” and wireless), and occupation rate (amount of information transmitted to the network versus the controller network scan time). These functions are accomplished without a single physical element installed in the network, using only simulation. The computer tool has a software that presents a detailed vision of the network to the user, besides showing some possible problems in the network, and having an extremely friendly environment. 相似文献
1000.
Antonio Flavio Midio Renata Rodrigues Campos Myrna Sabino 《Food Additives & Contaminants》2001,18(5):445-448
Samples of cooked components of regular meals served at fast food outlets of the city of Sa~oPaulo, Brazil were analysed for aflatoxins B1, B2, G1 and G2. The 322 samples were composed of prepared traditional Brazilian and ethnic foods in which aflatoxins might be present. Thin-layer chromatography was used for separation of the compounds and their determination was achieved by both long wave UV light and fluorodensitometry. Aflatoxins were detected in 30 samples (9.31% of the total) in a range of 2.80 to 1323 ng/g for B1 + B2 + G1 + G2 with 90th percentiles of 158 (B1 + G1) and 258 (B1 + B2 + G1 + G2). Aflatoxin B1 was detected in all contaminated samples. The contamination levels and frequency of aflatoxins B1 and G1 in positive samples above 20 ng/g in this study are high, indicating that there is a certain degree of exposure of the population to the carcinogenic aflatoxin. 相似文献