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排序方式: 共有916条查询结果,搜索用时 10 毫秒
61.
BT Holt NL Parks GA Engh JM Lawrence 《Canadian Metallurgical Quarterly》1997,20(12):1121-4; discussion 1124-5
One hundred thirty-six primary total knee arthroplasty patients were randomized for the use of closed-suction, nonreinfusable wound drains. Blood loss was identical in the drained and undrained groups. Forty percent of undrained wounds compared with 0% of drained wounds required dressing reinforcement. Sixty-nine percent of undrained wounds compared with 39% of drained wounds developed ecchymosis, measuring 92 cm2 in the undrained group and 28 cm2 in the drained group. This study concludes that a simple wound drain effectively minimizes the undesirable accumulation of blood in the surrounding soft tissues and the postoperative wound dressing after total knee arthroplasty. 相似文献
62.
63.
Lau Sing; Lew William J. F.; Hau Kit-Tai; Cheung Ping Chung; Berndt Thomas J. 《Canadian Metallurgical Quarterly》1990,26(4):674
In clarifying the relation between parent–child relationship and parental control, previous research has shown that parental warmth was associated positively with order-keeping parental organization and negatively with dominating parental control. The present study, with separate analyses for fathers and mothers, further examined the relations among adult perceptions of parental dominating control, warmth, indulgence, and family harmony. The subjects were 925 educated Chinese in mainland China, who were asked to recall the child-rearing pattern of their parents. As in previous research, it was found that greater perceived parental dominating control was related to less perceived parental warmth. Results also showed that greater parental warmth and less parental control were related to greater perceived family harmony. These relations were found in analyses for both fathers and mothers. Similarities in the relations among perceived parental behaviors between sons and daughters, and differences in the perceived paternal and maternal treatment of children, are also discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
64.
JL Abkowitz KE Brown RW Wood NL Kovach SW Green NS Young 《Canadian Metallurgical Quarterly》1997,176(1):269-273
Parvovirus B19 (B19) DNA was detected by dot blot hybridization in sera from 5 (17%) of 30 human immunodeficiency virus (HIV)-infected patients with hematocrits (HCT) of < or =24 and 4 (31%) of 13 HRV-infected patients with HCT of < or =20, suggesting that B19 is a reasonably common cause of severe anemia in HIV infection. The anemia promptly remitted after immunoglobulin therapy in 3 of 4 treated patients. The presence of IgM to B19, the clinical circumstance in which anemia developed, and the marrow morphology were poor predictors of chronic B19 infection. DNA hybridization studies of sera from 191 HIV-infected and 117 HIV-seronegative homosexual males attending a clinic in the Seattle area revealed that 1 (0.5%) and 2 (2%) samples, respectively, from the 2 groups contained B19. However, when assayed by polymerase chain reaction (PCR), 5% of the serum samples from HIV-infected persons and 9% from uninfected persons contained B19, although each had an HCT of > or =40. The data argue that anemia results from chronic high-titer B19 infection. Although a negative PCR assay excludes this diagnosis, DNA hybridization may be the more specific serum test. 相似文献
65.
RD Bloebaum NL Mihalopoulus JW Jensen LD Dorr 《Canadian Metallurgical Quarterly》1997,79(7):1013-1022
Microradiography, backscattered electron microscopy, and histological analysis were used to conduct a quantitative postmortem study of seven consecutively retrieved anatomical porous replacement acetabular components that had been inserted during total hip arthroplasties. Screws had been used for the initial fixation of six components. The microradiographic analysis of all seven components showed that an average (and standard deviation) of 84 +/- 9 per cent (range, 72 to 93 per cent) of the porous coating was in direct apposition to the periprosthetic bone. The backscattered electron images demonstrated that an average of 12 +/- 6 per cent (range, 4 to 21 per cent) of the space available in the porous coating was occupied by ingrown bone. The amount of bone ingrowth was not significantly different among the three zones delineated by DeLee and Charnley. Uniformity of bone growth into the porous coating suggests that the preferential loading that occurs in the superior region did not differentially affect the bone ingrowth. The present study showed that consistent bone growth into anatomical porous replacement acetabular components can be achieved. 相似文献
66.
JR Mayo M Remy-Jardin NL Müller J Remy DF Worsley C Hossein-Foucher JS Kwong MJ Brown 《Canadian Metallurgical Quarterly》1997,205(2):447-452
PURPOSE: To compare prospectively the accuracy of spiral computed tomography (CT) with that of ventilation-perfusion scintigraphy for diagnosing pulmonary embolism. MATERIALS AND METHODS: Within 48 hours of presentation, 142 patients suspected of having pulmonary embolism underwent spiral CT, scintigraphy, and (when indicated) pulmonary angiography. Pulmonary angiography was attempted if interpretations of spiral CT scans and of scintigrams were discordant or indeterminate and intermediate-probability, respectively. RESULTS: In the 139 patients who completed the study, interpretations of spiral CT scans and of scintigrams were concordant in 103 patients (29 with embolism, 74 without). In 20 patients, intermediate-probability scintigrams were interpreted (six with embolism at angiography, 14 without); diagnosis with spiral CT was correct in 16. Interpretations of spiral CT scans and those of scintigrams were discordant in 12 cases; diagnosis with spiral CT was correct in 11 cases and that with scintigraphy was correct in one. Spiral CT and scintigraphic scans of four patients with embolism did not show embolism. Sensitivities, specificities, and kappa values with spiral CT and scintigraphy were 87%, 95%, and 0.85 and 65%, 94%, and 0.61, respectively. CONCLUSION: In cases of pulmonary embolism, sensitivity of spiral CT is greater than that of scintigraphy. Interobserver agreement is better with spiral CT. 相似文献
67.
A stereoselective reversed-phase liquid chromatographic method for the determination of compounds LY300502 and LY300503 (enantiomers of LY191704) in rat and dog plasma was developed. The assay involved extraction of the compounds using a strong cation-exchange solid-phase extraction column, from which the compounds are eluted with 1% of 1 M HCI in methanol. The enantiomers were separated on a Daicel Chiralcel OD-R column. The mobile phase consisted of water-acetonitrile-methanol (50:40:10, v/v) at a flow-rate of 0.3 ml/min. UV detection was achieved at 220 nm. The disposition of the enantiomers of LY191704 in rats and dogs was found to be stereoselective and species specific. 相似文献
68.
69.
Cris Cecka Adrian J. Lew E. Darve 《International journal for numerical methods in engineering》2011,85(5):640-669
Recently, graphics processing units (GPUs) have had great success in accelerating many numerical computations. We present their application to computations on unstructured meshes such as those in finite element methods. Multiple approaches in assembling and solving sparse linear systems with NVIDIA GPUs and the Compute Unified Device Architecture (CUDA) are created and analyzed. Multiple strategies for efficient use of global, shared, and local memory, methods to achieve memory coalescing, and optimal choice of parameters are introduced. We find that with appropriate preprocessing and arrangement of support data, the GPU coprocessor using single‐precision arithmetic achieves speedups of 30 or more in comparison to a well optimized double‐precision single core implementation. We also find that the optimal assembly strategy depends on the order of polynomials used in the finite element discretization. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
70.
0引言
总部位于美国纽约的宋腾添玛沙帝工程顾问有限公司(Thornton Tomasetti lnc.,简称TT),是一个专长大型复杂结构设计的公司,其凭借专业实力,参与了世界前20个超高层建筑中近一半项目的结构设计,包括已建成的中国台湾台北市的世界金融中心(即台北101)、马来西亚吉隆坡的双子石油大厦、上海的恒隆广场和正在建设中的上海中心、芝加哥螺旋塔、平安国际金融中心等。 相似文献