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81.
Intracerebral infection of mice aged 2-3 days with hepatitis C virus (HCV) from chronically infected suckling mouse brain cultures and porcine embryo cells resulted in the death of animals after 12-14 days. Repeated passages of HCV in animals decreased the incubation period to just 3-4 days. Blood serum of surviving mice collected during the 4th week postinfection contained antiHCV antibodies detected by enzyme immunoassay and hemagglutination inhibition test. The results are proof of creation of a new in vivo model of experimental HCV infection. 相似文献
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We analyzed 79 consecutive patients with aneurysms and found a patient who lacked type III collagen. Collagen was extracted from the skin, and the lack of type III collagen was determined by means of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Only 1 of the 79 patients was found to lack type III collagen. This patient was a 55-year-old man who had sustained an abdominal aortic aneurysm and aortic dissection. He did not show any of the typical clinical symptoms of Ehlers-Danlos syndrome type IV, such as hyperextensible skin and joints. He had none of the usual risk factors nor any clear family history of the syndrome. Furthermore, his collagen fibrils demonstrated a homogeneous appearance. This case may represent a new form of type III collagen deficiency. 相似文献
84.
DM Adams JS Sholl EI Haney TL Russell RK Silver 《Canadian Metallurgical Quarterly》1998,178(4):843-847
A recent review of the relevant literature indicates that different approaches to the exploration of nurses' clinical reasoning are being adopted in North America, Australia and the United Kingdom. These differing approaches, which tend to cluster chronologically and which include decision analysis, information processing and skills acquisition theory and their limitations will be outlined; it will be argued that it is through their conflation that nurses' collective understanding of nurses' clinical reasoning is deepened. The author is attempting to develop an international network of nurse scholars interested in clinical reasoning with the aim of achieving this. The purposes of this network will be to facilitate international collaboration to expedite both the growth of knowledge related to nurses' clinical reasoning and the development of programs of international comparative research related to it. The setting up of this network and progress to date is described. 相似文献
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The purpose of this study was to assess the possibility of measuring directional microphone hearing aids (DMHAs) using standard hearing aid test instruments in a sound field environment. The use of DMHAs is increasing and research has shown that under certain difficult listening situations, superior results are obtained by hearing impaired individuals with directional versus omnidirectional microphone arrangements. However, valid electroacoustic evaluation of the DMHAs cannot be accomplished using the conventional hearing aid test box. The ideal environment for such evaluations is an anechoic chamber, a facility not found in most audiological clinics. Results show that if the proper precautions are observed, the electroacoustic characteristics of DMHAs can be measured in a sound field environment using conventional hearing aid test instrumentation. Validation of this procedure was carried out by comparing sound field results with those obtained in an anechoic chamber. 相似文献
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O. I. Popova 《Powder Metallurgy and Metal Ceramics》1974,13(5):399-401
Conclusions A study was made of the chemical stability of four powdered vanadium germanides (V3Ge, V5Ge3, V11Ge8, and VGe2) in acid and alkali solutions and their mixtures with solutions of oxidizing and complex forming agents, and also in atmospheric oxygen at 500–750°C. It is shown that vanadium germanides are unstable compounds, which are readily decomposed by hydrochloric, sulfuric, and nitric acids, hydrogen peroxide, and other reagents and also readily oxidized by the oxygen in the air at temperatures above 550°C.Translated from Poroshkovaya Metallurgiya, No. 5 (137), pp. 67–69, May, 1974. 相似文献
90.