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61.
Pre-clerking of all patients undergoing elective general surgical operations was introduced at our hospital in an attempt to reduce an unacceptably high operation cancellation rate. A prospective audit has been performed on the effect of this policy on the cancellation rate. Before the introduction of pre-clerking there was a marked seasonal variation in the number of patients who failed to attend for surgery, which could be explained by absence on holiday. This seasonal variation disappeared after the start of pre-clerking clinics, but there has been no reduction in the number of cancellations for medical reasons.  相似文献   
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Magnetorheological materials have been used in many applications in recent years. To develop new materials, polyurethane and silicone polymer gels were investigated. Rheology is qualitatively controlled for each system by controlling the concentration of reactants and diluents. The resulting polymers have solid, gel, or liquid states, depending on the crosslinking and dilution. The gels were characterized through kinetic analysis. Differential scanning calorimetry (DSC) was used with analysis methods to find the kinetic properties for diluted and undiluted polyurethane systems. Heat of reaction, order of reaction, preexponential constant, and activation energy were obtained from the experimental DSC data. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2733–2742, 2002  相似文献   
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LA Mastaj  DJ Tartakow  AJ Borislow  MS Fogel 《Canadian Metallurgical Quarterly》1994,15(1):74, 76, 78-80, passim; quiz 86
Infections present a significant hazard in the orthodontic office because they can be transmitted by blood or saliva through direct or indirect contact, droplets, aerosols, or contaminated instruments and equipment. Because the incidence of certain microbial cross-infections in the dental environment has not been well documented, orthodontic personnel may not take the problem of cross-infection as seriously as they should, and they may transmit or contract more infections than they realize. The use of effective infection-control procedures in the orthodontic office and laboratory will prevent cross-contamination that may extend to the orthodontist, office staff, assistants, and patients. The goal of this article is to present infection control in a simple, yet comprehensive, manner, and to encourage all orthodontic practitioners to implement essential infection-control procedures in their practices.  相似文献   
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Calmodulin and de-phosphorylated B-50/growth-associated protein-43 (GAP-43) have been shown to bind in vitro in a molecular complex, but evidence for an in situ association in the nervous system does not exist. Previously, we have reported that, in the model of the regenerating rat sciatic nerve, the B-50/GAP-43 immunoreactivity is increased and concentrated at the axolemma of unmyelinated axons located proximal to the site of injury and axon outgrowth. To explore a putative function of B-50/GAP-43, namely, the capacity of binding calmodulin to the plasma membrane, we examined the ultrastructural distribution of calmodulin in the proximal unmyelinated axon shafts of this model, using double immunolabelling and detection by fluorescent or gold probes conjugated to second antibodies. Immunofluorescence showed that seven days post-sciatic nerve crush the calmodulin immunoreactivity, similar to B-50/GAP-43 immunoreactivity, was intense in unmyelinated axon shafts located proximal to the site of injury of the regenerating nerve. Ultrastructurally, calmodulin was located at the axolemma of these regenerating unmyelinated axon shafts and inside the axoplasm, where it was associated with vesicles and microtubules. The plasma membrane labelling (approximately 69%) was significantly higher than the axoplasmic labelling. Over 60% of the plasma membrane-associated calmodulin co-localized with B-50/GAP-43 in a non-random distribution. Since normally calmodulin is largely present in the cytoplasm, these data suggest that calmodulin has been concentrated at the plasma membrane of unmyelinated axons, most probably by B-50/GAP-43. If the concentrating effect is due to B-50/GAP-43, then there is a possibility that these proteins may be present as a molecular complex in situ. The physiological significance could be that this association regulates the local availability of both B-50/GAP-43 and calmodulin for other interactions.  相似文献   
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A procedure is described by which the length of a tendon at the onset of loading is determined objectively. The procedure includes the fitting of third-order polynomial functions on the load-elongation data. The onset of loading is detected by an increasing fit of the polynomial by selective data reduction of the initial part of the load-elongation curve. The procedure results in an objective and reproducible definition of the zero strain level of a tendon.  相似文献   
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Thoracoscopy provides a minimally invasive technique for the diagnosis and management of many posterior mediastinal masses. Benign neurogenic tumors, esophageal tumors, and bronchogenic cysts all can be approached using video-assisted thoracic surgical (VATS) techniques. Malignant lesions are still best approached via open thoracotomy. VATS techniques allow for less pain and dysfunction and can result in shortened hospital stays.  相似文献   
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