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801.
In investigating the stress effects of chilling (2-3 degrees C) and hypothermia (2-3 degrees C drop in body core temperature mediated by exposure to hyperbaric helium-oxygen atmosphere) on mouse resistance to "influenza," it was noted that these stresses adversely affected the course of pulmonary infection produced by aerosols of the NWS strain of influenza virus. Comparatively, respiratory LD50 values for control animals were about 25 virus plaque-forming units (PFU) with median mortality occurring on day 13. The LD50 values for mice chilled at 2-3 degrees C were about 15 PFU with median mortality on day 7, and for mice exposed to hyperbaric helium, about 12 PFU with median mortality on day 6. Cold or hyperbaric stress impaired interferon production. Impairment was observed at 24 h but not at 12 h post-challenge and persisted for several days until mice became moribund.  相似文献   
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Diseases are increasingly being defined in terms of genetic alterations. A body of information termed "molecular pathogenesis" is evolving which provides a framework for integrating the rapidly accumulating genetic information with the related disease process. Molecular methods with their increased sensitivity and specificity are required to gather this information. A major challenge now lies in the transfer of this molecular technology from a research environment to the clinical testing arena. Technical issues, patented technology, special facilities, personnel, and regulatories issues imposed by CLIA'88, require those desiring to perform molecular tests to pay special attention to laboratory design, personnel training, and test menu development. Although establishing a successful molecular diagnostics laboratory is a complex and difficult task, the added value of these tests can have a tremendous impact in disease diagnosis and patient management.  相似文献   
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In sarcoidosis, pulmonary and general symptoms often do not correlate with radiographic stage and routinely performed lung function tests. Asymptomatic muscle involvement in sarcoidosis is common, but little is known about respiratory muscle involvement. The aim of this study was to investigate any relationships between persistent complaints and/or quality of life and respiratory muscle strength and endurance, respectively. Measurements of maximal inspiratory and expiratory mouth pressures (PI,max and PE,max), respiratory muscle endurance and routine lung function were made in 18 patients with sarcoidosis. To assess health status and quality of life, patients completed the Sickness Impact Profile (SIP). Respiratory muscle strength and endurance time were lower in the patient group than in a group of healthy controls (p=0.05). Compared to a general population, the patients with sarcoidosis were found to be limited in physical and psychosocial functioning. The respiratory muscle endurance time correlated with the SIP subscales "mobility" (r=-0.56; p<0.01), and "body care and movement" (r=-0.79; p<0.001). The total lung capacity (TLC), inspiratory vital capacity (IVC) and forced expiratory volume in one second (FEV1) were normal in all subjects. In conclusion, patients with sarcoidosis and normal lung function showed reduced respiratory muscle strength and endurance time. Correlations were found between these indices and both symptoms and certain Sickness Impact Profile domains. Therefore, we suggest inclusion of measurements of respiratory muscle strength in the assessment and follow-up of patients with sarcoidosis.  相似文献   
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Subacromial bursal specimens from 63 patients undergoing surgery for rotator cuff tearing (n = 43), the impingement syndrome (n = 14), and calcifying tendinitis n = 6) were studied to characterize the reactions that develop at the tendinopathy "lesional" sites. Intensity of the bursal reactions and production of type III collagen vary considerably, with the highest incidence of both seen in patients with rotator cuff tears. The intensity of bursal reactions correlated with the degree of formation of perivascular new collagen and type III collagen expression. In 22 of the 63 patients the bursal reaction distant to the tendon lesion was also studied. It was minimal and did not correlate to the lesional bursal findings. A strong correlation, however, existed between surgical appearance and histologic grading. The term "localized bursal reaction" as opposed to bursitis more correctly describes bursal involvement. Resection of bursal tissues should be limited to the lesional tissue that interferes with subacromial motion.  相似文献   
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To the list of eastern United States localities known for excellent amethyst scepter crystals must be added this little-known locality.  相似文献   
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