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排序方式: 共有2564条查询结果,搜索用时 15 毫秒
91.
T Rand M Breitenseher J Haller W Graninger H Imhof S Trattnig 《Canadian Metallurgical Quarterly》1996,36(8):617-623
Rheumatoid arthritis is a chronic, multisystemic disease. The characteristic feature is persistent inflammatory synovitis. The knee joint is commonly involved with synovial hypertrophy, chronic effusion, and frequently ligamentous laxity. Pain and swelling behind the knee may be caused by extension of inflamed synovium into the popliteal space (Baker's cyst). Plain radiographs of the knee joint remain the basic radiological procedure, although early in the disease they might not provide significant changes. Sonography sufficiently reveals synovial fluid and Baker cysts, but cannot be recommended for evaluation of synovial proliferations or pannus formation. Computer tomography has only limited indications and may be used for the evaluation of subtle erosive lesions or the quantitation of osteoporotic changes. Magnetic resonance imaging has shown excellent visualization of cartilage, fluid, synovium and soft tissues and is the method of choice for the demonstration of early affection and the evaluation of pannus activity and therapy control. With administration of contrast agents (gadolinium), dynamic studies may demonstrate inflammatory activity. Modern MR sequences, such as T1 SE "fat sat" or magnetization transfer, further improve the discrimination of cartilage, pannus and synovial fluid. 相似文献
92.
Analysis of the S-phase fractions (SPF) measured by in vitro thymidine labeling, morphological appearances, and estrogen receptor (ER) assays of primary invasive breast carcinomas demonstrated several interrelationships. Lobular, mucinous, tubular, and adenocystic carcinomas consistently had low SPF and were usually positive for ER. The same was true for the carcinomas of no special histologic type [the not otherwise specified (NOS) group of E. R. Fisher including "infiltrating ductal" and undifferentiated carcinomas] with minimal anaplasia. Medullary, atypical medullary, and morphologically unclassifiable carcinomas with marked nuclear anaplasia nearly always had high SPF and were usually negative for ER. High SPF was associated with advanced stages of carcinoma initially or with early recurrence following mastectomy. 相似文献
93.
Investigation of soybean oil as a diesel fuel extender: Endurance tests 总被引:14,自引:0,他引:14
C. Adams J. F. Peters M. C. Rand B. J. Schroer M. C. Ziemke 《Journal of the American Oil Chemists' Society》1983,60(8):1574-1579
Engine performance and crankcase lubricant viscosity were followed with 1∶2 and 1∶1 fuel mixtures of degummed soybean oil
in No. 2 diesel fuel in tests with a John Deere 6-cylinder, 404 cubic in. displacement, direct-injection, turbocharged engine
for a total of 600 running hours. A crankcase oil contamination problem resulting in an unacceptable thickening and a potential
for gelling did exist with a 50/50 blend or a greater concentration of soybean oil, but it did not occur with the 1∶2 blend.
The data accumulated during the initial 600 hr running time indicates that a fuel blend of one-third degummed soybean oil
and two-thirds No. 2 diesel (1∶2 blend) may be a suitable fuel for agricultural equipment during periods of diesel fuel shortages
or allocations. Additional data are being accumulated and will be analyzed in the future. 相似文献
94.
Intravenous glucose tolerance test in middle-aged men with and without latent coronary heart disease
During a cardiovascular survey, aimed at detecting cases of latent coronary heart disease (CHD), glucose elimination was studied after i.v. loading in 1970 presumably healthy men aged 40-59 years. The aim was to throw light on the importance of deranged glucose tolerance for the development of CHD. Of the 1970 individuals, 1798 were defined as "normals", 33 had chronic, non-anginal chest pain, 34 had slight albeit typical angina pectoris. The remaining 105 had various symptoms/signs strongly suggestive of CHD, and underwent diagnostic coronary angiography (69 angiopositive, 36 angionegative). Plasma insulin was determined in relation to the test in 249 of the subjects. The following conclusions were reached: 1) Mean k-values were similar in all subgroups (p less than 0.10). 2) Low and borderline k-values were significantly more frequent in angiographed individuals compared with the group of normals (p less than 0.025). However, an almost identical frequency was seen in angiopositive and angionegative cases. 3) K-values did not change with age between 40 and 59 years. 4) K-values were unrelated to the severity of angiographic findings in individuals with proven CHD. 5) Significantly lower k-values were found in individuals with a positive diabetic heredity, and 6) in individuals with a high insulin response. 7) The i.v. glucose loading did not influence an exercise ECG recorded in relation to a near-maximal bicycle exercise test. 相似文献
95.
Myocardial biopsies from two patients who had developed "stone heart" (myocardial rigor mortis; ischemic contracture of the left ventricle) were studied by electron microscopy. The ultrastructure of tissue in stone heart, though ischemic in nature, differed from that of classic myocardial infarction in some respects. Apart from depletion of glycogen and distension of the sarcoplasmic reticulum and T-tubules, myofibrillar degeneration was much more widespread. Mitochondrial degeneration with active lysosomal autodigestion, disruption of the microcirculation, and lymphedema were prominent changes also observed. In the light of known clinical and experimental observations, our findings suggest that stone heart is an accelerated form of ischemic injury occurring in vulnerable (hypertrophied) hearts and is probably related to ischemia-triggered release of endogenous catecholamines. 相似文献
96.
Back Cover: Mapping the Interactions of Selective Biochemical Probes of Antibody Conformation by Hydrogen–Deuterium Exchange Mass Spectrometry (ChemBioChem 11/2017)
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97.
James L. Rand John K. Henderson Debora A. Grant 《Polymer Engineering and Science》1996,36(8):1058-1064
To predict the response of polyethylene thin films subjected to stress for a long time, it is necessary to understand the influence of stress on either the relaxation modulus or creep compliance. Extensive testing has been conducted on 20-micron-thick samples of a particular linear low-density polyethylene film at temperatures from 23°C to −50°C. When reduced to creep compliance and compared with results from dynamic mechanical analysis (DMA), the influence of nonlinearities in the response function is apparent. However, the use of a two-step loading procedure has produced sufficient data to discriminate between the effect of stress on amplitude and time on the creep compliance. It has been found that a master curve of compliance generated by DMA equipment may be used in conjunction with certain nonlinear functions to accurately predict the response of the polyethylene. Perhaps of more importance is the observation that the principles of simple time-temperature superposition, commonly used with linear viscoelastic characterization, are insufficient for use with polyethylene films at most stress levels of interest. 相似文献
98.
J. E. Cotter A. M. Barnett D. H. Ford R. B. Hall A. E. Ingram J. A. Rand T. R. Ruffins K. P. Shreve C. J. Thomas 《Progress in Photovoltaics: Research and Applications》1995,3(5):351-358
Thin-film polycrystalline silicon has the potential to achieve the cost reduction and performance improvement necessary for large-scale electricity markets. Reduced cost is achieved by capitalizing on the benefits of thin films grown on low-cost, large-area substrates. Improved efficiency is realized, in spite of reduced material quality, by incorporating enhanced optical absorption and back-surface passivation. The cornerstone of AstroPower's thin-film solar cell technology is the Silicon-Film™ process: a method for the manufacture of solar cell-quality, polycrystalline films of silicon on a variety of low-cost, supporting substrates. Three thin-film solar cell designs, based on this technology, are currently under development. This paper presents the key design features of these three products and briefly reviews the current status of the development of the key technologies that comprise the advanced thin-film solar cell products. 相似文献
99.
100.
Peder Rand 《今日电子》2009,(3)
消费电子射频(RF4CE)联盟是针对消费类电子产品遥控器的一种协议标准.松下、飞利浦、三星电子和索尼公司组成的企业联盟正在推动这一标准化进程.它们的目标是,通过运用于遥控器的双向RE通信实现高可靠性和众多新颖功能,从而向消费者提供更多价值. 相似文献