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排序方式: 共有642条查询结果,搜索用时 31 毫秒
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S Mattila L Heikkil? J Sipponen K Verkkala K Ky?sola T Mattila A J?rvinen R Luosto L Heikkinen P Ketonen J Salo A Nemlander I Mattila MS Nieminen 《Canadian Metallurgical Quarterly》1997,86(2):113-120
BACKGROUND: Clearance of large molecules from the interstitial space is an important function of lymphatics and is affected by local pathologic changes. OBJECTIVE: To determine if the clearance rate of interstitially injected albumin is correlated to tumour characteristics and outcome in women with invasive breast cancer. METHOD: In a consecutive series of women coming to biopsy for suspected breast cancer, technetium-tagged albumin was injected into the tissue adjacent to the palpable mass. The isotope disappearance rate was measured over two hours. Also assessed were the maximum vessel density (MVD-using Factor VIII polyclonal antisera), the proliferation rate (using Ki-67 antisera), node status, tumour size, histologic and nuclear grade, mitotic rate, and p53 and c-erbB-2 oncoproteins. All patients were followed until relapse and for a minimum of 10 years. RESULTS: In multivariate analysis, an association between relapse-free survival and isotope clearance rate was suggested (p = 0.024). The best outcome was seen in patients with the least isotope clearance. Node status, size, histologic and nuclear grade, and mitotic rate correlated with survival. MVD did not correlate with survival and was inversely related to the isotope clearance rate. Tumour proliferation rate, and the c-erbB-2 and p53 oncoproteins did not relate to outcome. CONCLUSION: The role of lymphatics in breast cancer is difficult to study. Measurement of interstitial clearance may be a useful technique and could be a prognostic factor. 相似文献
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Nitrofurantoin is a commonly used urinary tract antibiotic that has been found at high concentrations in human milk. In vivo studies in rats were carried out to determine the mechanism by which this drug crosses the mammary epithelium. Lactating rats were gavage-fed with nitrofurantoin, and their milk and plasma levels of the antibiotic were measured at intervals up to 8 hr. The average milk-to-plasma (M/P) ratio, calculated from the areas under the milk and plasma curves, respectively, was 23 compared with a ratio predicted to be about 0.3 on the basis of lipid partitioning and protein binding determinations. M/P ratios for two nitrofurantoin congeners were also calculated. The neutral compound furazolidone had a M/P ratio of about 1, as predicted, whereas the basic compound furaltadone had a M/P ratio of 3.49 compared with a predicted ratio of 1.4. These data suggest that nitrofurantoin and, to a lesser extent, furaltadone are actively transported across the mammary epithelium into milk. 相似文献
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Ari Paasio Adam Dawidziuk Kari Halonen Veikko Porra 《Analog Integrated Circuits and Signal Processing》1997,12(1):59-70
The paper presents a Cellular Neural Network implementation based on a high gain sigmoid operation. The required simplifications to the original theory are described that allow the use of high gain. With this design black and white images can be processed. The basic building blocks in a cell are described. A 16×16 cells network has been designed and processed with 1.2 micron CMOS technology. Measurement results which show the operation of the network are presented. 相似文献
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Susan J. Masten Kuan‐Chung Chen Jaime Graulau Subhash L. Kari Kyung‐Hyuk Lee 《工程教育杂志》2002,91(1):69-80
The use of computer‐based technology is becoming more prevalent in the classroom. As a part of an educational research project sponsored by the GE Foundation, strategies for augmenting a course, Introduction to Environmental Engineering (CE 280), were investigated including cross‐disciplinary experiences in teamwork, design, and the use of advanced teaching technologies such as the web. Interactive tools to assist student learning were developed and refined. Efforts have focused on developing an extensive website, web‐based quizzes and homework assignments, and tutorials. Base groups were used to provide both intellectual and emotional support to students. This paper summarizes the development of this course and the impact of rapid feedback on the progression of student understanding. 相似文献
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Ravaja Niklas; Kallinen Kari; Saari Timo; Keltikangas-Jarvinen Liisa 《Canadian Metallurgical Quarterly》2004,10(2):120
The authors examined the effects of suboptimally presented facial expressions on emotional and attentional responses and memory among 39 young adults viewing video (business news) messages from a small screen. Facial electromyography (EMG) and respiratory sinus arrhythmia were used as physiological measures of emotion and attention, respectively. Several congruency priming effects were found. In particular, happy facial primes prompted increased (a) pleasure ratings, (b) orbicularis oculi EMG activity, (c) perceived trustworthiness, and (d) recognition memory for video messages with a positive emotional tone. Emotional and other responses to video messages presented on a small screen can be modified with suboptimal affective primes, but even small differences in the emotional tone of the messages should be allowed for. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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An expenmental and theoretical study of heat and mass transfer analogy and a comparison of that to a binary liquid mixture evaporation is presented. Common organic solvents, ethanol and n-heptane, were used to form an alcohol - hydrocarbon mixture. Studies were carried out in a horizontal rectangular channel having air flow velocities of 0.2 - 0.9 m/s. Heat transfer coefficients were measured with a copper plate resistor and mass transfer coefficients with a square pool. The heat and mass transfer analogy is presented for a system having two evaporating compounds with a fixed value of air flow and verified by measuring and comparing mass transfer coefficients for distilled water with air flow velocities of 0.2 - 0.9 mls. An illustrative example of the use of the theory for industrial ventilation is presented. 相似文献