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991.
AR Antonov II Buzueva IM Korostyshevskaia VF Maksimov AL Markel' NA Makhanova EE Filiushina MD Shmerlin GS Iakobson 《Canadian Metallurgical Quarterly》1998,(9):36-40
The morphological and functional consequences of epinephrine-induced myocardial infarction were studied in normo- (Wistar) and hypertensive (ISIAH) rats. After experimental myocardial infarction there was an irreversible transition to the "worn-out" stage or "plastic damage" to the myocardium. Thus, myocardial hibernation in ISIAH rats anticipates and determines the development of myocardial stunning, i.e., irreversible myocardial damage, whereas in the normotensive animals, the protective effect of hibernation is fully shown. The ontogenetic features of myocardial response of ISIAH rats to hypoxia promote transformation of adaptive hibernation and stunning to maladaptive pathological changes causing hypoxic alterations. 相似文献
992.
993.
Pellagra, a disease rarely seen in developed countries today, was common during the first half of this century in the United States. The disease was initially believed to be infectious, and severe "pellagraphobia" left many victims and their families ostracized. This paper calls attention to Joseph Goldberger, an American physician whose remarkable research helped correct the erroneous belief in an infectious cause for pellagra and led to the elimination of pellagra epidemics in the United States. 相似文献
994.
NE Byars EB Fraser-Smith RA Pecyk M Welch G Nakano RL Burke AR Hayward AC Allison 《Canadian Metallurgical Quarterly》1994,12(3):200-209
PURPOSE: This study was designed to develop improved criteria for the diagnosis of infective endocarditis and to compare these criteria with currently accepted criteria in a large series of cases. PATIENTS AND METHODS: A total of 405 consecutive cases of suspected infective endocarditis in 353 patients evaluated in a tertiary care hospital from 1985 to 1992 were analyzed using new diagnostic criteria for endocarditis. We defined two "major criteria" (typical blood culture and positive echocardiogram) and six "minor criteria" (predisposition, fever, vascular phenomena, immunologic phenomena, suggestive echocardiogram, and suggestive microbiologic findings). We also defined three diagnostic categories: (1) "definite" by pathologic or clinical criteria, (2) "possible," and (3) "rejected." Each suspected case of endocarditis was classified using both old and new criteria. Sixty-nine pathologically proven cases were reclassified after exclusion of the surgical or autopsy findings, enabling comparison of clinical diagnostic criteria in proven cases. RESULTS: Fifty-five (80%) of the 69 pathologically confirmed cases were classified as clinically definite endocarditis. The older criteria classified only 35 (51%) of the 69 pathologically confirmed cases into the analogous probable category (p < 0.0001). Twelve (17%) pathologically confirmed cases were rejected by older clinical criteria, but none were rejected by the new criteria. Seventy-one (21%) of the remaining 336 cases that were not proven pathologically were probable by older criteria, whereas the new criteria almost doubled the number of definite cases, to 135 (40%, p < 0.01). Of the 150 cases rejected by older criteria, 11 were definite, 87 were possible, and 52 were rejected by the new criteria. CONCLUSION: Application of the proposed new criteria increases the number of definite diagnoses. This should be useful for more accurate diagnosis and classification of patients with suspected endocarditis and provide better entry criteria for epidemiologic studies and clinical trials. 相似文献
995.
Periodically, reviews of our knowledge of radar–wetland relationships and detection parameters have been provided by various authors. Since the publication of these works, additional research has been completed. Five major remote sensing journals spanning the years 1965–2007 formed the basis of this review. The vast majority of significant material found its way into these mainstream journals in one aspect or another. A short history of Synthetic Aperture Radar (SAR)–wetlands discovery based on earlier reviews is followed by an update on radar‐related wetland research. Although some trends emerged with regard to which wavelengths or polarizations to use, there was variation in optimum season/time of year and selection of multitemporal imagery. What is evident throughout the recent literature is that multidimensional radar data sets are attaining an accepted role in operational situations needing information on wetland presence, extent and conditions. 相似文献
996.
Henderson S Feiner S 《IEEE transactions on visualization and computer graphics》2011,17(10):1355-1368
We explore the development of an experimental augmented reality application that provides benefits to professional mechanics performing maintenance and repair tasks in a field setting. We developed a prototype that supports military mechanics conducting routine maintenance tasks inside an armored vehicle turret, and evaluated it with a user study. Our prototype uses a tracked headworn display to augment a mechanic's natural view with text, labels, arrows, and animated sequences designed to facilitate task comprehension, localization, and execution. A within-subject controlled user study examined professional military mechanics using our system to complete 18 common tasks under field conditions. These tasks included installing and removing fasteners and indicator lights, and connecting cables, all within the cramped interior of an armored personnel carrier turret. An augmented reality condition was tested against two baseline conditions: the same headworn display providing untracked text and graphics and a fixed flat panel display representing an improved version of the laptop-based documentation currently employed in practice. The augmented reality condition allowed mechanics to locate tasks more quickly than when using either baseline, and in some instances, resulted in less overall head movement. A qualitative survey showed that mechanics found the augmented reality condition intuitive and satisfying for the tested sequence of tasks. 相似文献
997.
The thermal expansion of sodium -and '-alumina in thea andc directions has been determined by high temperature X-ray diffractometry using polycrystalline samples. The measured values show that internal stresses as a result of anisotropy in the thermal expansion of the two phases should have little adverse effect on the application of beta-alumina in electrochemical devices. 相似文献
998.
Kyle Luthy Edward Grant Nikhil Deshpande Thomas C. Henderson 《Robotics and Autonomous Systems》2012,60(2):266-277
For a mobile robotic agent to bridge the gaps between disconnected networks, it is beneficial for the robot to first determine the network coverage boundary. Several techniques have been introduced to determine the boundary nodes of a network, but the correctness of these techniques is often ill-defined. We present a technique for obtaining boundary node ground truth from region adjacency analysis of a model-based image created from a network graph. The resulting ground truth baseline is then used for quantitative comparison of several boundary detection methods including a local application of the image region adjacency analysis and the computation of the local convex hull with the addition of a perturbation value to overcome small boundary concavities in the node location point set. Given our proposed metrics of the techniques evaluated, the perturbed convex hull technique demonstrates a high success rate for boundary node identification, particularly when the convex hull is formed using two-hop neighborhoods. This technique was successfully implemented on a physical 25-node network, and the performance of this network implementation is evaluated. 相似文献
999.
Nigg Joel T.; Stavro Gillian; Ettenhofer Mark; Hambrick David Z.; Miller Torri; Henderson John M. 《Canadian Metallurgical Quarterly》2005,114(4):706
Dual-process models of attention-deficit/hyperactivity disorder (ADHD) suggest that both executive functioning and regulatory functions (e.g., processing speed) are involved and that executive function weaknesses may be associated specifically with symptoms of inattention-disorganization but not hyperactivity-impulsivity. Adults aged 18-37 (105 with ADHD, 90 controls) completed a neuropsychological battery. The ADHD group had weaker performance than did the control group (p = .01) on both executive and speed measures. Symptoms of inattention-disorganization were uniquely related to executive functioning with hyperactivity-impulsivity controlled. Inattention was associated with slower response speed, and hyperactivity-impulsivity with faster output speed. Results were not accounted for by IQ, age, gender, education level, or comorbid disorders. Findings are discussed in terms of developmental and dual-process models of ADHD leading into adulthood. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
Homayun K. Navaz Brenda S. Henderson Ramin Faramarzi Ahmad Pourmovahed Frederic Taugwalder 《International Journal of Refrigeration》2005,28(2):961
Experimental and computational methods are used to address those parameters that have significant effects on the amount of entrained (warm) air in an open refrigerated display case. These parameters are identified, quantified, and the rate of entrainment is expressed as a function of these parameters. It is found that the turbulence intensity, the shape of the mean velocity profile at the discharge air grill, and the Reynolds number are mainly responsible for the amount of entrained air in a display case. It is also concluded that lower Reynolds numbers will reduce the amount of the entrained air in the display case, however, the trade off will be higher temperature of the food products on shelves. Digital particle image velocimetry (DPIV) was used to map the entire mean velocity flowfield and the turbulence intensity. The laser doppler velocimetry technique was also used to verify the mean velocity and turbulence intensity measurements made by DPIV. The results indicated an excellent agreement between both methods. Parametric studies for the rate of entrainment of the outside air into the display case were performed using a computational fluid dynamics tool. The results indicate that lowering the Reynolds number of the air curtain reduces the entrainment rate. However, sufficiently high momentum should still exist to enforce the integrity of the air curtain structure. 相似文献