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91.
Responsiveness of self-reported and objective measures of disease severity in carpal tunnel syndrome
JN Katz RH Gelberman EA Wright RA Lew MH Liang 《Canadian Metallurgical Quarterly》1994,32(11):1127-1133
Responsiveness, the ability to detect meaningful clinical change, is a critical attribute of instruments used to evaluate outcomes of treatments. The authors hypothesized that self-administered symptom severity and functional status questionnaires are more responsive to clinical improvement after carpal tunnel release than traditional physical examination measures of strength and sensibility. Data were obtained from a randomized clinical trial of endoscopic versus open carpal tunnel release conducted in four university medical centers. Patients were evaluated before surgery and 3 months after surgery. Seventy-four patients indicating that they were more than 80% satisfied with the results of surgery were assumed to have clinically meaningful improvement and were the focus of the analysis. Evaluations included questionnaires assessing symptom severity, functional status, and activities of daily living as well as measurement of grip, pinch, and abductor pollicus brevis strength, and 2-point discrimination and Semmes-Weinstein pressure sensibility. Responsiveness was calculated with the standardized response mean (mean change/standard deviation of change) as well as the effect size (mean change/standard deviation of baseline values). The symptom severity scale was four times as responsive, and the functional status and activities of daily living scales were twice as responsive, as the measures of strength and sensibility. Self-administered symptom severity and functional status scales are much more responsive to clinical improvement than measures of neuromuscular impairment and should severe as primary outcomes in clinical studies of therapy for carpal tunnel syndrome. 相似文献
92.
93.
Lossless compression techniques are essential in archival and communication of medical images. Here, a new segmentation-based lossless image coding (SLIC) method is proposed, which is based on a simple but efficient region growing procedure. The embedded region growing procedure produces an adaptive scanning pattern for the image with the help of a very-few-bits-needed discontinuity index map. Along with this scanning pattern, an error image data part with a very small dynamic range is generated. Both the error image data and the discontinuity index map data parts are then encoded by the Joint Bi-level Image Experts Group (JBIG) method. The SLIC method resulted in, on the average, lossless compression to about 1.6 b/pixel from 8 b, and to about 2.9 b/pixel from 10 b with a database of ten high-resolution digitized chest and breast images. In comparison with direct coding by JBIG, Joint Photographic Experts Group (JPEG), hierarchical interpolation (HINT), and two-dimensional Burg prediction plus Huffman error coding methods, the SLIC method performed better by 4% to 28% on the database used 相似文献
94.
ElectronmicroscopicobservationsandDNAchainfragmentationstudiesonapoptosisinbonetumorcelsinducedby153SmEDTMPZhuShouPeng,Xia... 相似文献
95.
L Ma S Broomfield C Lavery SL Lin W Xiao S Bacchetti 《Canadian Metallurgical Quarterly》1998,17(10):1321-1326
Inactivation of 5-HT1A and [3H]5-HT binding sites by N-Ethoxycarbonyl-2-ethoxy-1, 2-dihydroquinoline (EEDQ) was studied in regions of rat brain. After exposure to EEDQ (4 mg/kg body wt.) for 7 days, it is observed that the density of 5-HT1 receptor sites was decreased by nearly 20% in both cortex and hippocampus. The decrease, however, in 5-HT1A sites was more significant (70%) in both the regions. The affinity of [3H]5-HT to 5-HT1 sites was decreased significantly in both cortex and hippocampus after exposure to EEDQ, without affecting the Kd of 5-HT1A sites. Displacement studies suggested that EEDQ has high affinity to 5-HT1 sites with a Ki of 42.9+/-2.4 nM. After exposure neither basal nor 5-HT stimulated adenylyl cyclase activity was changed in cortex. The results of this study suggest that EEDQ decreases the density of 5-HT1 and 5-HT1A receptor sites but does not cause functional downregulation of these sites in rat brain. 相似文献
96.
97.
容错磁盘阵列的性能模型 总被引:1,自引:1,他引:0
本文以排队论为工具,建立了容错磁盘阵列的M/G/1排队模型,并在此基础上分析了RAID的平均响应时间,稳定数据传输率等重要性能指标;比较了同步和异步RAID的性能差异,最后提出了以吞吐率作为衡量RAID性能的综合指标,并给出了确定最大吞吐率的定量。 相似文献
98.
99.
S Liang Y Ohtsuki J Iwata M Furihata E Ido H Sonobe 《Canadian Metallurgical Quarterly》1996,50(5):279-283
Epithelioid hemangioendothelioma is a relatively rare lesion. Although its histogenesis has been well described, its immunohistochemical characteristics remain controversial. A case of epithelioid hemangioendothelioma of the soft tissue of the right leg in a 67-year-old Chinese woman is reported. Histologic findings of intracytoplasmic lumina in the tumor cells and positive immunostaining for vimentin, factor VIII-related antigen. CD34 and Ulex europaeus agglutinin 1 (UEA-1) were obtained, demonstrating differentiation of the tumor cells to endothelial cells, although staining for antibodies to cytokeratins AE1/AE3 and CAM5.2 was weak. CD34 as well as Factor VIII-related antigen is a useful marker of endothelial differentiation in this tumor. A review of the literature is also presented. 相似文献
100.
Yufei Tao Xiaokui Xiao Jian Pei 《Knowledge and Data Engineering, IEEE Transactions on》2007,19(8):1072-1088
Skyline and top-k queries are two popular operations for preference retrieval. In practice, applications that require these operations usually provide numerous candidate attributes, whereas, depending on their interests, users may issue queries regarding different subsets of the dimensions. The existing algorithms are inadequate for subspace skyline/top-k search because they have at least one of the following defects: 1) they require scanning the entire database at least once, 2) they are optimized for one subspace but incur significant overhead for other subspaces, or 3) they demand expensive maintenance cost or space consumption. In this paper, we propose a technique SUBSKY, which settles both types of queries by using purely relational technologies. The core of SUBSKY is a transformation that converts multidimensional data to one-dimensional (1D) values. These values are indexed by a simple B-tree, which allows us to answer subspace queries by accessing a fraction of the database. SUBSKY entails low maintenance overhead, which equals the cost of updating a traditional B-tree. Extensive experiments with real data confirm that our technique outperforms alternative solutions significantly in both efficiency and scalability. 相似文献