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991.
We present a case in which the growth of an intraosseous cyst arising from the proximal tibiofibular joint appeared to have been increased by polyethylene wear particles from a medial unicompartmental knee replacement. Histological examination of the cyst wall showed a histiocytic response associated with numerous polyethylene wear particles. This case demonstrates that there is a direct communication between the joint cavity and the cyst. Such communication is probably through openings in the articular cartilage large enough to allow the passage of these particles. 相似文献
992.
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994.
Vanbo Pak 《Measurement Techniques》1962,5(6):475-481
Conclusions The results arrived at in the present work served as a basis for making an automatic equipment for dynamic calibration of platinum-platinorhodium thermocouples [5]. Experimental investigation of this equipment confirmed the correctness of the above analysis of systematic errors due to transient processes.The conclusions arrived at in the present work can be applied for measuring small temperature differences in electrical conducting media by means of two thermocouples without electrical insulation between the operating junction of one of them and the measured medium. 相似文献
995.
MoO3-modified porous glasses are prepared via impregnation with aqueous ammonium molybdate, followed by thermal decomposition of the salt. With increasing MoO3 content, the edge of the charge-transfer band shifts to longer wavelengths. The photochromic properties of the modified glass are well defined at an MoO3 content of about 14 mol/g. 相似文献
996.
Surface normal overlap: a computer-aided detection algorithm with application to colonic polyps and lung nodules in helical CT 总被引:1,自引:0,他引:1
Paik DS Beaulieu CF Rubin GD Acar B Jeffrey RB Yee J Dey J Napel S 《IEEE transactions on medical imaging》2004,23(6):661-675
We developed a novel computer-aided detection (CAD) algorithm called the surface normal overlap method that we applied to colonic polyp detection and lung nodule detection in helical computed tomography (CT) images. We demonstrate some of the theoretical aspects of this algorithm using a statistical shape model. The algorithm was then optimized on simulated CT data and evaluated using a per-lesion cross-validation on 8 CT colonography datasets and on 8 chest CT datasets. It is able to achieve 100% sensitivity for colonic polyps 10 mm and larger at 7.0 false positives (FPs)/dataset and 90% sensitivity for solid lung nodules 6 mm and larger at 5.6 FP/dataset. 相似文献
997.
Generic number systems and haplotype analysis 总被引:1,自引:0,他引:1
Three simple and elegant algorithms involving binary and mixed-radix numbers are presented as C subroutines and applied to gene-counting procedure. The first, a multikey radix-sorting subroutine, is used to tally individuals with similar genetic marker information. The second, a subroutine for N-ary number addition, is used to enumerate all possible phases of a heterozygote. The third, a mixed-radix number subroutine, is used to generate all haplotypes and indexing single array of haplotype frequencies. Examples exposing these algorithms are also given. The sorting algorithm entails broad application while the N-ary and mixed-radix number algorithms are very efficient for generic looping. Implementation of gene-counting using these algorithms avoids use of multilocus genotype identifier and improves its portability to other analysis. 相似文献
998.
SD Pack E Pak A Tanigami DH Ledbetter MN Fukuda 《Canadian Metallurgical Quarterly》1998,83(1-2):76-77
It is a sad fact that even with liberal doses of curiosity, an interesting issue and enough time and money, many good research ideas fail to reach the stage of a completed project. Not all of us have the time to devote to the research methods courses and workshops that have sprung up around the country in the past few years. The Research Committee of the RACGP plans to help. This is the first article in a series that will provide the new GP researcher with guidelines on asking the right question, choosing the best method, and getting results published. The series aims to make research in general practice more accessible by demystifying the jargon, clarifying the statistics and explaining the rules of publication. 相似文献
999.
RG Kurumbail AM Stevens JK Gierse JJ McDonald RA Stegeman JY Pak D Gildehaus JM Miyashiro TD Penning K Seibert PC Isakson WC Stallings 《Canadian Metallurgical Quarterly》1996,384(6610):644-648
Prostaglandins and glucocorticoids are potent mediators of inflammation. Non-steroidal anti-inflammatory drugs (NSAIDs) exert their effects by inhibition of prostaglandin production. The pharmacological target of NSAIDs is cyclooxygenase (COX, also known as PGH synthase), which catalyses the first committed step in arachidonic-acid metabolism. Two isoforms of the membrane protein COX are known: COX-1, which is constitutively expressed in most tissues, is responsible for the physiological production of prostaglandins; and COX-2, which is induced by cytokines, mitogens and endotoxins in inflammatory cells, is responsible for the elevated production of prostaglandins during inflammation. The structure of ovine COX-1 complexed with several NSAIDs has been determined. Here we report the structures of unliganded murine COX-2 and complexes with flurbiprofen, indomethacin and SC-558, a selective COX-2 inhibitor, determined at 3.0 to 2.5 A resolution. These structures explain the structural basis for the selective inhibition of COX-2, and demonstrate some of the conformational changes associated with time-dependent inhibition. 相似文献
1000.