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991.
992.
AR Kennedy 《Canadian Metallurgical Quarterly》1996,350(1):81-91
A method is described using counterflow centrifugation elutriation to isolate macrophages from murine liver and spleen. In this study three, size fractionated, macrophage populations were collected. Isolation resulted in a high yield of pure Kupffer cells (total of 10 x 10(6) /g liver) and enrichment of splenic macrophages to 20%. In addition to standard methods such as non-specific esterase staining, the isolated macrophages were also characterized by flow cytometry using specific monoclonal antibodies. In addition, a rapid flow cytometry method was introduced to determine the percentage of macrophages based on autofluorescence. A strong correlation was found between the percentages of macrophages found by non-specific esterase staining and autofluorescence. Functional tests revealed differences between the isolated macrophages in terms of tumor necrosis factor-alpha (TNF-alpha) production, oxygen metabolism and the production of nitric oxide. However, no significant differences in phagocytic activity was observed between the fractions. After two weeks of culture without the addition of antibiotics the cells still exhibited the above mentioned functions. 相似文献
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The experience of space missions shows that functional disorders in crewmembers on the type of space motion sickness (SMS) may develop on the initial stage of flight. Longer exposure in micro-g causes a wide range of debilitative changes in the vital body systems. Artificial gravity produced by spacecraft rotation might be a universal tool to counteract the impacts of prolonged microgravity on the human body. However, the significance of SMS does not become less high because of a new factor, i.e. the rotating environment. Research system Jupiter 2 is a stand-alone slow-rotating ground facility for simulating motion sickness equivalent to its space form. The merits of this facility are the possibilities to control the intensity of exposure, perform long-term investigations of two active subjects simultaneously, and study the stages of body adaptation to this agent, and assess physical and operator's performance. The facility carries large expectations to occupational selection. 相似文献
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P Naud M Busetti E Becker A Camozzato R Siegler J Cavagnoli E Machado G Bender Lima AR Timm 《Canadian Metallurgical Quarterly》1996,30(4):391-394
The vibration-induced finger flexion reflex (VFR) and the inhibitory effect of acupuncture on this reflex were studied in five cervical spinal cord injury patients (C-SCIs). VFR, which is a tonic finger flexion reflex induced by vibratory stimulation on the finger tip, was induced before and after acupuncture was carried out on the same hand. A stainless steel needle was inserted to the Hoku point. As in healthy subjects, VFR was performed and it was significantly inhibited by acupuncture in the C-SCIs; mean maximum VFR was 204.2 +/- S.E. 68.6 g before and 119.8 +/- S.E. 42.2 g after acupuncture. The present results suggest that at least part of the reflex center for VFR is located in the spinal cord and that part of VFR inhibition by acupuncture may be mediated via the spinal cord. 相似文献
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AR Neurath AK Debnath N Strick YY Li K Lin S Jiang 《Canadian Metallurgical Quarterly》1995,8(5):304-316
An evaluation of the effects of the ABLE (Analyzing Behavior State and Learning Environments) model was presented. Eight teachers received training on observing behavior state and relevant environmental variables; analyzing potential effects of nutrition and medications; identifying strategies for individual students; and participating in a process to generate classroom-based intervention strategies based on their observations. Results showed that teachers were able to reliably implement the model, which produced significant increases in occurrences of the preferred alert and active states and significant decreases in nonpreferred states, such as sleep, drowse, daze, and crying/agitated. Additional findings indicated that the teachers were satisfied with the training procedures and found the model to be relevant and appropriate for students with profound mental retardation. Case studies were briefly presented. 相似文献
1000.
OBJECTIVE. The flexor tendon pulley system is often ruptured when a flexed finger is forcibly extended. In the acute phase, soft-tissue swelling and pain often make clinical evaluation difficult. These pulleys are not constantly visualized on MR imaging. Rupture of the pulley system can be inferred by observing bow stringing of the underlying flexor tendons when MR imaging is obtained with the finger in flexion. Our objective is to describe the flexor tendon pulley system and present our MR technique. 相似文献