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排序方式: 共有263条查询结果,搜索用时 15 毫秒
71.
The development of risk assessment models for carpal tunnel syndrome: a case-referent study 总被引:1,自引:0,他引:1
The present study developed risk assessment models for carpal tunnel syndrome (CTS) which can provide information of the likelihood of developing CTS for an individual having certain personal characteristics and occupational risks. A case-referent study was conducted consisting of two case groups and one referent group: (1) 22 work-related CTS patients (W-CTS), (2) 25 non-work related CTS patients (NW-CTS), and (3) 50 healthy workers (HEALTHY) having had no CTS history. The classification of CTS patients into one of the case groups was determined according to the type of insurance covering their medical costs. Personal characteristics, psychosocial stresses at work, and physical work conditions were surveyed by using a questionnaire tailor-designed to CTS (reliability of each scale > or = 0.7). By contrasting the risk information of each case group to that of the referent group, three logistic regression models were developed: W-CTS/HEALTHY, NW-CTS/HEALTHY, and C-CTS/HEALTHY (C-CTS, the combined group of W-CTS and NW-CTS). ROC analysis indicated that the models have satisfactory discriminability (d' = 1.91 to 2.51) and high classification accuracy (overall accuracy = 83-89%). Both W-CTS/HEALTHY and C-CTS/HEALTHY include personal and physical factors, while NW-CTS/HEALTHY involves only personal factors. This suggests that the injury causation of NW-CTS patients should be attributable mainly to their 'high' personal susceptibility to the disorder rather than exposure to adverse work conditions, while that of W-CTS patients be attributable to improper work conditions and CTS-prone personal characteristics in combination. 相似文献
72.
Precipitation of basic drugs within oral prolonged release systems, at the higher pH values of the intestine, would affect drug release. Coevaporates of a model basic drug verapamil HCl, in single or mixed polymer systems, containing Eudragit L100 (L100) and ethyl cellulose or Eudragit RS100, were prepared from ethanolic solution. XRD and DSC indicated loss of crystallinity of the drug in the coevaporates. The presence of the enterosoluble polymer in the system was found to aid in faster dissolution of the drug at higher pH values. This was affected by the presence and type of retarding polymer present in the system. Compression of the coevaporates resulted in either very slow release of the drug or undesirable changes in the release profile. Pelletization of a coevaporate containing drug and L100 yielded systems, which released the drug uniformly when studied by the buffer change method in simulated gastric (SGF) and intestinal (SIF) fluids. The presence of L100 in intimate contact with the drug was found to be essential for the desirable drug release properties of the system. The drug release occurred predominantly by diffusion in SGF and by a combination of diffusion and polymer dissolution/erosion in SIF. Appropriate choice of release modifiers and formulation variables and development of suitable formulations can yield systems which compensate for the reduced solubility of the drug in the higher pH environments of the intestine. 相似文献
73.
74.
Amit Bandyopadhyay Vamsi Krishna Balla Mangal Roy Susmita Bose 《JOM Journal of the Minerals, Metals and Materials Society》2011,63(6):94-99
Load-bearing metal implants often fail prematurely due to inadequate biocompatibility, mechanical/tribological properties,
and poor osseointegration. It is well known that biomaterials’ surface plays a vital role in the response to these metal implants
in the biological environment. The biological effectiveness of artificial implants is determined mainly by their surface characteristics
such as surface morphology, microstructure, composition, mechanical properties, wettabilility, and surface free energy. Hence,
there is significant interest toward surface modification and effective design of load-bearing metal implants so as to improve
their surface properties and thereby elicit a specific, desired, and timely response from the surrounding cells and tissues.
In this article, we provide an insight into laser surface modification of Ti/Ti6Al4V alloy with or without functional gradation
in composition and their microstructural, in vitro wear and biological properties for various loadbearing orthopedic applications. 相似文献
75.
The objective of the present work is to establish a convolutional type (Gurtin in Arch. Rat. Mech. Anal. 16:34?C50, 1964) variational theorem and a reciprocity theorem for the linear theory of generalized thermoelastic diffusion for homogeneous and isotropic elastic solids. 相似文献
76.
Catalytic nanomotors with silica microbead heads and TiO(2) arms are systematically designed by dynamic shadowing growth. The swimming trajectories are fine tuned by altering the arm length and orientation exploiting geometry-dependent hydrodynamic interactions at low Reynolds number. The curvature, angular frequency, and radius of curvature of the trajectories change as a function of arm length. Simulations based on the method of regularized Stokeslets are also described and correctly capture the trends observed in the experiments. 相似文献
77.
Julius Oben Ebangha Enonchong Shil Kothari Walter Chambliss Robert Garrison Deanne Dolnick 《Nutrition journal》2009,8(1):38-9
Background
The objective of this clinical study was to assess the potential benefit of a dietary supplement, NP 06-1, on joint health in overweight and normal weight adults diagnosed with osteoarthritis. 相似文献78.
A review of single-phase improved power quality AC-DC converters 总被引:2,自引:0,他引:2
Singh B. Singh B.N. Chandra A. Al-Haddad K. Pandey A. Kothari D.P. 《Industrial Electronics, IEEE Transactions on》2003,50(5):962-981
Solid-state switch-mode rectification converters have reached a matured level for improving power quality in terms of power-factor correction (PFC), reduced total harmonic distortion at input AC mains and precisely regulated DC output in buck, boost, buck-boost and multilevel modes with unidirectional and bidirectional power flow. This paper deals with a comprehensive review of improved power quality converters (IPQCs) configurations, control approaches, design features, selection of components, other related considerations, and their suitability and selection for specific applications. It is targeted to provide a wide spectrum on the status of IPQC technology to researchers, designers and application engineers working on switched-mode AC-DC converters. A classified list of more than 450 research publications on the state of art of IPQC is also given for a quick reference. 相似文献
79.
80.
Mathematical morphology has proven invaluable for signal/image processing. Fuzzy theory is enjoying great success in control and signal processing. We show that stack filters, which are already related to morphology, require slight modification to implement basic fuzzy operators. The article therefore provides a fast errorless method for implementation of basic fuzzy operations 相似文献