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排序方式: 共有777条查询结果,搜索用时 234 毫秒
691.
P Caligiuri ML Giger MJ Favus H Jia K Doi LB Dixon 《Canadian Metallurgical Quarterly》1993,186(2):471-474
Measurement of bone mass is important in determining the risk for fracture and in following the course of patients undergoing therapy for osteoporosis. Bone mineral densitometry (BMD) is a good predictor of fracture risk, but there is considerable overlap in BMD measurements between individuals with fracture risk and those without. In this study, computerized texture analysis of the trabecular pattern on conventional spine radiographs was used to evaluate bone structure as a determinant of fracture risk. Standard lumbar spine radiographs of 43 individuals were analyzed and compared with BMD measurements obtained with dual-photon absorptiometry. This method was more effective than BMD in differentiation of patients with fractures elsewhere in the spine from those with no fracture. These preliminary results suggest that this method of bone structure analysis, combined with BMD, may lead to a more sensitive and specific predictor of osteoporosis and risk of fracture. 相似文献
692.
Magnetic resonance imaging of the knee was performed in 28 patients (ages 15-72 years), using a 1.5-T unit. Volume gradient echo (3D GRASS) acquisition with and without presaturation off-resonance RF pulse was used to evaluate magnetization transfer (MT) effects, determined by placing regions of interest on muscle, fat, hyaline, and fibrocartilage; the percent change in signal intensity was calculated and compared using a paired two-sample t test. An in vitro study of the normal meniscus from a cadaver containing a scalpel cut extending to an articular surface was performed to observe the relative improvement in contrast in the presence of a small meniscal defect. MR imaging of the specimen was performed using an Omega CSI 2.0-T system (General Electric Medical Systems, Fremont, CA). Analysis of clinical images resulted in signal loss, compared to that of the identically timed and tuned non-MT images of 47 +/- 5, 8 +/- 5, 49 +/- 5, and 57 +/- 7% for muscle, fat, articular cartilage and fibrocartilage, respectively. Application of MT improved the depiction of the artificially introduced meniscal defect. Meniscal fibrocartilage demonstrates significant MT effect after application of off-resonance RF presaturation, which may improve visualization of meniscal defects. 相似文献
693.
Print exposure as a predictor of word reading and reading comprehension in disabled and nondisabled readers. 总被引:1,自引:0,他引:1
McBride-Chang Catherine; Manis Franklin R.; Seidenberg Mark S.; Custodio Rebecca G.; Doi Lisa M. 《Canadian Metallurgical Quarterly》1993,85(2):230
The relation of print exposure, measured by a revised version of A. E. Cunningham and K. E. Stanovich's (1990) Title Recognition Test (TRT), to word reading and reading comprehension was examined in disabled and nondisabled readers, Grades 5–9. In disabled readers, the TRT was a significant predictor of word reading when phonological skill was accounted for but not when orthographic ability was added to the regression equation, suggesting that the TRT overlaps considerably with orthographic skill. The TRT significantly predicted nondisabled readers' word reading after both phonological and orthographic skills were accounted for. The TRT contributed significantly to reading comprehension once variance was partialed from higher order reading processes for disabled readers only. The TRT's power to predict comprehension may be ascribed to the effects of print exposure on automaticity of word recognition, knowledge, or familiarization with text structure. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
694.
695.
K Kuriyama R Tateishi T Kumatani K Kodama O Doi N Hosomi Y Sawai E Inoue T Kadota Y Narumi 《Canadian Metallurgical Quarterly》1994,191(2):365-369
Cystic endometrial hyperplasia resembling that of normal early pregnancy was induced by the insertion of a silk suture into diestrous bitches. Intraluminal trauma (wire scratching) induced a similar but moderate change. Intraluminal olive oil and saline had little or no effect. Maternal decidual response in rodentia produced by mechanical means in progesterone-stimulated uteri in the absence little or no effect. Maternal decidual response in rodentia produced by mechanical means in progesterone-stimulated uteri in the absence of fertilized ova is termed Loeb's deciduoma. A similar response was created in progesterone-stimulated canine uteri by various physical means when compared to the pregnant contralateral horn. 相似文献
696.
697.
We describe a simple bench top method for fabricating boron-doped diamond (BDD) microband electrodes and copper-modified BDD microband electrodes. The method described here is inexpensive, robust, renewable, simple, and the BDD microband electrodes and the copper-modified BDD microband electrodes are very easy to fabricate. An advantage of the method is not only its simplicity but also the renewability. That is, even if the surface of the electrode is deactivated after an electrochemical reaction, it can be renewed by simply cutting off the end. As one of the example of application, we report on the selective detection of glucose in solution containing interference species such as Ascorbic acid (AA) and Uric acid (UA) by preparing Cu-modified BDD microband electrodes. Even in solutions containing 2 or 3 times the amount of interfering species compared to the glucose concentration, the Cu-modified BDD microband electrodes showed good selectivity and high durability. 相似文献
698.
699.
Thermally stimulated current studies of commercially available soda-lime and pyrex glasses were made within the temperature range 170–700 K. Three different polarization peaks were found and compared with the peaks for alkali-rich glasses. The data were interpreted in terms of the heterogeneous distribution of alkali ions and structural rearrangement of the silicon network near the electrodes. 相似文献
700.