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排序方式: 共有307条查询结果,搜索用时 344 毫秒
31.
K Aabo M Adams P Adnitt DS Alberts A Athanazziou V Barley DR Bell U Bianchi G Bolis MF Brady HS Brodovsky H Bruckner M Buyse R Canetta V Chylak CJ Cohen N Colombo PF Conte D Crowther JH Edmonson C Gennatas E Gilbey M Gore D Guthrie BY Yeap 《Canadian Metallurgical Quarterly》1998,78(11):1479-1487
The purpose of this systematic study was to provide an up to date and reliable quantitative summary of the relative benefits of various types of chemotherapy (non-platinum vs platinum, single-agent vs combination and carboplatin vs cisplatin) in the treatment of advanced ovarian cancer. Also, to investigate whether well-defined patient subgroups benefit more or less from cisplatin- or carboplatin-based therapy. Meta-analyses were based on updated individual patient data from all available randomized controlled trials (published and unpublished), including 37 trials, 5667 patients and 4664 deaths. The results suggest that platinum-based chemotherapy is better than non-platinum therapy, show a trend in favour of platinum combinations over single-agent platinum, and suggest that cisplatin and carboplatin are equally effective. There is no good evidence that cisplatin is more or less effective than carboplatin in any particular subgroup of patients. 相似文献
32.
Enderes Thomas Khoo Swee Chern Somerville Clare A. Samaras Kostas 《Mobile Networks and Applications》2002,7(2):153-161
This paper examines the quality of transmission of voice over cellular, packet-switched networks. The medium access mechanism in the uplink is simulated under various statistical multiplexing scenarios in order to assess the effect of front-end clipping on voice quality. Moreover, the simulation is implemented in a real-time demonstration platform utilized to acquire subjective indicators of voice quality by performing Mean Opinion Score (MOS) tests. Results from the MOS tests are reported, and an analysis of the obtained speech samples is presented. Finally, the results are summarized and potential further directions for the simulation tool and the speech models are discussed. 相似文献
33.
The moisture effect on the indentation force deflection (IFD) of flexible polyurethane foam was examined through the curing of the foam with different moisture contents. The employed foam was cured at 30, 40, 50, 60, 70, and 80% relative humidity, and the corresponding curing temperature was constant at 23°C. The experiments showed that the measured IFD and support factor of the flexible polyurethane foam decreased, and the hysteresis increased with the curing moisture. A statistical conversion formula was generated experimentally to correct the measured IFD of the flexible polyurethane foam to eliminate the deviation caused by the moisture effect. The measured IFD was inversely exponentially proportional to the curing moisture. The accuracy of the correction formula was verified by the conditioning of the foam again with different moisture contents. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1679–1682, 2007 相似文献
34.
A New In Situ Microscopy Approach to Study the Degradation and Failure Mechanisms of Time‐Dependent Dielectric Breakdown: Set‐Up and Opportunities 下载免费PDF全文
Zhongquan Liao Martin Gall Kong Boon Yeap Christoph Sander Oliver Aubel Uwe Mühle Jürgen Gluch Sven Niese Yvonne Standke Rüdiger Rosenkranz Markus Löffler Norman Vogel Armand Beyer Hans‐Jürgen Engelmann Peter Guttmann Gerd Schneider Ehrenfried Zschech 《Advanced Engineering Materials》2014,16(5):486-493
35.
36.
Duan Liu Nam Quoc Ngo Swee Chuan Tjin Xinyong Dong 《Photonics Technology Letters, IEEE》2007,19(15):1148-1150
A strain and temperature-sensing scheme based on a dual-wavelength fiber laser is demonstrated experimentally. By measuring the change in the wavelength separation of the two lasing wavelengths and the shift of any of two lasing wavelengths, the measured strain and temperature are very linear and have a strain sensitivity of 0.15 pm/muepsiv over a range of 0-2400 muepsiv and a temperature sensitivity of 14.3 pm/degC over a range of 22degC-230degC, respectively. 相似文献
37.
A direct sampling method was developed to verify the cleanliness of stainless steel equipment used to produce peanut products. The protocol consisted of sampling the product-contact area with two Critical Swab® flat zapped-head foam swabs pre-moistened with 20 mM phosphate, pH 7.2 (PBS), mixing each swab in PBS for 1 h, and analyzing the extract for peanut residues. Quantitation of peanut residues was accomplished with a non-specific assay while SDS–PAGE was used to ensure the recovery of the allergen, Ara h 1. This sampling approach was able to recover 90–95% of the peanut proteins at sub-microgram levels and Ara h 1 at low nanogram levels directly from a stainless steel surface. 相似文献
38.
Swee Yeow Yap McCanny J.V. 《Circuits and Systems II: Express Briefs, IEEE Transactions on》2004,51(7):384-389
With the advent of new video standards such as MPEG-4 part-10 and H.264/H.26L, demands for advanced video coding, particularly in the area of variable block size video motion estimation (VBSME), are increasing. In this paper, we propose a new one-dimensional (1-D) very large-scale integration architecture for full-search VBSME (FSVBSME). The VBS sum of absolute differences (SAD) computation is performed by re-using the results of smaller sub-block computations. These are distributed and combined by incorporating a shuffling mechanism within each processing element. Whereas a conventional 1-D architecture can process only one motion vector (MV), this new architecture can process up to 41 MV sub-blocks (within a macroblock) in the same number of clock cycles. 相似文献
39.
SS Yeap M Beaumont A Bennett NA Keating DA White DJ Hosking 《Canadian Metallurgical Quarterly》1998,74(872):349-354
This study assessed whether relatives with low bone mineral density (BMD) could be identified in five large families using historical, biochemical, and genetic markers for osteoporosis. Fifty of 65 relatives had their bone density and bone turnover markers measured, together with an assessment of their risk factors for osteoporosis. Only 33% (5/15) of siblings, 50% (6/12) of children and 43% (10/23) of nephews and nieces had entirely normal BMD. There was no difference in life-style risk factors for osteoporosis, history of previous fractures or body mass index between normal subjects and those with osteopenia or osteoporosis. Osteopenic individuals had a significantly higher than normal osteocalcin value. Within families, there was no clear association between BMD and any of the genetic markers (vitamin D receptor gene polymorphisms, COL 1A1 and COL 1A2 polymorphisms of the collagen gene), either alone or in combination. The addition of genetic markers to the other risk factors for low BMD did not improve the prediction of BMD. In conclusion, we suggest that the presence of osteoporosis in a first degree relative should be one of the clinical indications for bone density measurement as the individuals at risk would not be picked up by other methods. 相似文献
40.
Swee Chuan Tjin Seng Lee Ng Kian Thiam Soo 《IEEE transactions on bio-medical engineering》1998,45(10):1272-1278
A new fiber-optic catheter for in vivo blood-flow measurements has been developed. The catheter is designed to measure blood flow in both the forward (toward the catheter tip) and reverse (away from the catheter tip) flow directions. It consists of two multimode optical fibers with core diameter of 50 μm and cladding diameter of 125 μm. One fiber transmits the laser beam into blood and the other receives the backscattered light from the erythrocytes within the probe volume. In the flow experiment, it was found that the flow within the boundary layer is indeed laminar and, hence, the relationship between the Doppler shift frequencies and the flow velocities is linear, thereby making the linear calibration possible for predicting the free stream flow velocity. Plots of the maximum shift frequency (frequency at which the Doppler spectrum disappeared into the noise spectrum) against the flow velocities are found to be more linear in both the forward and reverse flow directions than that of the dominant shift frequency (frequency with the highest amplitude). These results were reaffirmed by the numerical flow simulation along the catheter side wall 相似文献