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排序方式: 共有1961条查询结果,搜索用时 15 毫秒
991.
JM Ferro AN Pinto I Falc?o G Rodrigues J Ferreira F Falc?o E Azevedo P Canh?o TP Melo MJ Rosas V Oliveira AV Salgado 《Canadian Metallurgical Quarterly》1998,29(6):1106-1109
BACKGROUND AND PURPOSE: The first medical contact of an acute stroke victim is often a nonneurologist. Validation of stroke diagnosis made by these medical doctors is poorly known. The present study seeks to validate the stroke diagnoses made by general practitioners (GPs) and hospital emergency service physicians (ESPs). METHODS: Validation through direct interview and examination by a neurologist was performed for diagnoses of stroke made by GPs in patients under their care and doctors working at the emergency departments of 3 hospitals. RESULTS: Validation of the GP diagnosis was confirmed in 44 cases (85%); 3 patients (6%) had transient ischemic attacks and 5 (9%) suffered from noncerebrovascular disorders. Validation of the ESP diagnosis was confirmed in 169 patients (91%); 16 (9%) had a noncerebrovascular diagnosis. Overall, the most frequent conditions misdiagnosed as stroke were neurological in nature (cerebral tumor, 3; subdural hematoma, 1; seizure, 1; benign paroxysmal postural vertigo, 1; peripheral facial palsy, 2; psychiatric condition, 6; and other medical disorders, 7). CONCLUSIONS: In the majority of cases, nonneurologists (either GPs or ESPs) can make a correct diagnosis of acute stroke. Treatment of acute stroke with drugs that do not cause serious side effects can be started before evaluation by a neurologist and CT scan. 相似文献
992.
993.
Jonatas S. Romano Flávio A. Rodrigues Lauro T. Bernardi José A. Rodrigues Nádia Segre 《Journal of Materials Science》2006,41(6):1775-1779
This work describes the utilization of rice hull as raw-material for the preparation of two calcium silicates namely, β-Ca1.91Ba0.04SiO4 and β-Ca1.96Ba0.04SiO4. The synthesis was completed at 800°C. Hydration rate and compressive strength of mortars prepared with the two calcium silicates
were studied and compared to mortars prepared with commercial Portland cement. Hydration rates for both silicates, studied
by thermogravimetric and FTIR analysis are very similar; after 60 days the hydration rates are around 42–43% and reaches 75%
after 270 days. Compressive strength experiments were performed using test specimen prepared with commercial Portland cement
as reference, and blends of Portland cement and the two calcium silicates, at replacement levels of 10 and 20%. Results have
shown that after a 90 days curing period, the compressive strength of the reference and the blends containing 10% of each
of the calcium silicates show the same behavior. Using a replacement level of 20% there is a small decrease in compressive
strength. This behavior is attributed to the lower hydration rate of these calcium silicates. 相似文献
994.
This paper presents a performance analysis of optical burst switching (OBS) networks with ring and chordal ring topologies. The performance analysis considers signaling protocols with one-way reservation schemes, being focused on the following protocols: just-in-time (JIT), Jumpstart, JIT+, just-enough-time (JET) and Horizon. It is shown that for a network with 20 nodes, the nodal degree gain due to the increase of nodal degree from two (ring) to three (chordal ring) is about three orders of magnitude in the first hop of both topologies, and is between two and three orders of magnitude in the last hop of each topology. It is also shown that the largest chord length gain, in a 20-node OBS network with a chordal ring topology, is slightly less than two orders of magnitude. 相似文献
995.
Because of their complexity, war injuries inflicted by a blast mechanism often require tailoring of treatment to attain a more individualized solution. We report two cases of bilateral, severely mangled lower limbs with open tibial fractures and crush injuries to the feet. In each case, one limb had to be amputated below the knee, but the other limb was saved by immediate stabilization in a tubular external fixation frame crossing the knee; the frame was later replaced by a hybrid ring fixation frame with a freely moving knee. Such incidences are rare, and the particular management detailed here has not previously been reported in the literature. 相似文献
996.
Rafael Resende Maldonado Elizama Aguiar‐Oliveira Eduardo Luiz Pozza Fátima Aparecida Almeida Costa Francisco Maugeri Filho Maria Isabel Rodrigues 《Journal of the American Oil Chemists' Society》2014,91(12):1999-2009
The production of an extracellular lipase using corn steep liquor (CSL) as the nitrogen source in the cultivation of Geotrichum candidum NRRLY‐552 was evaluated. The optimized conditions in shake flasks were CSL, 8.0 % w/v, soybean oil, 0.6 % w/v, pH 7.0, 30 °C, 250 rpm, and 48 h, resulting in a maximum lipase productivity of 0.438 U mL?1 h?1(U = the amount of enzyme required to liberate 1 μmol of fatty acid per minute). Scale‐up was evaluated with airlift and stirred tank reactors; the best conditions, respectively, were 1 vvm(volume of gas per volume of medium per minute) of aeration which resulted in 0.535 U mL?1 h?1 (32 h) and 1 vvm and 300 rpm resulting in 0.563 U mL?1 h?1 (16 h). To facilitate downstream processes, lipase production was also evaluated using CSL previously clarified with activated charcoal resulting in 0.275 U mL?1 h?1 (24 h) using 12 % (w/v) of clarified CSL in shake flasks. The obtained results showed that CSL leads to similar productivity compared to peptone using the same microorganism under similar conditions. In addition the cost of fermentation medium using CSL is much lower because it is a very inexpensive by‐product from corn processing. 相似文献
997.
998.
999.
The morphology of the pineal gland of the yellow‐toothed cavy (Galea Spixii Wagler, 1831) and red‐rumped agouti (Dasyprocta leporina linnaeus, 1758)
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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
1000.
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