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31.
This study presents a novel approach to decant supernatant on a centrifugal platform. By manipulating the centrifugally induced pressure and the elastic deformation of the plastic lids in the decanting chamber, fixed amounts of the supernatant can be decanted into the detection chamber at lower rotational speeds. The experimental results showed that decanted volume is affected by the volume of deformation and the operating parameters. Factors that influence the decanting ratio are also discussed. This approach has the advantages of simple design and low manufacturing cost; further, it has no need of surface modification. It has been applied to on-disk separation of plasma from whole blood, and the results showed good stability and repeatability.  相似文献   
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驾驭混沌   总被引:2,自引:0,他引:2  
Ditto  WL 王世德 《科学中国》1993,(12):40-46,33
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33.
Actinomycosis is an uncommon disease, which is usually manifested as cervicofacial infection and related to poor oral hygiene or compromised immune function. Pulmonary actinomycosis is rare, but its diagnosis is changing due to its variable presentation and the similarity in appearance to other intrapulmonary diseases. Here we report an 80-year-old man with a solitary pulmonary nodule over the left upper lobe. Pulmonary neoplasm was highly suspected in this patient and thus resection of the mass was undertaken through video-assisted thoracic surgery (VATS). Histopathological examination demonstrated this patient had an Actinomyeces infection. While the application of VATS in patients with pulmonary actinomycosis has rarely been reported in literature, we conclude that VATS is valuable for the diagnosis and treatment of patients with undetermined pulmonary nodule(s).   相似文献   
34.
This study examined the effect of shoulder angle and gender on physiological and perceptual responses during incremental peak arm ergometry. Healthy adults (nine males, seven females) volunteered for the study and completed an incremental arm ergometry test on two separate occasions at two different shoulder angles (90 degrees and 45 degrees). Initial work rate was set at 16 W x min-1 and was increased progressively until exhaustion. Cardiorespiratory and perceptual responses were recorded at the end of each minute and compared using separate three-way (position x work rate x gender) repeated-measures analyses of variance. The systematic bias of peak responses was examined using separate two-way (position x gender) analyses of variance, while reproducibility of these parameters was explored using intraclass correlation coefficients, measurement bias/ratio, and 95% ratio limits of agreement. Despite a significantly greater peak heart rate for the 45 degrees position, cardiorespiratory and perceptual responses were similar at peak exercise for both positions. Peak values for all variables, although similar, demonstrated similar and large inter-test variability for men and women. Reduction of the shoulder joint angle to 45 degrees did not enhance peak work rate and peak oxygen consumption during seated upper body exercise. Due to the large inter-test variability, arm ergometry should be conducted using the same seated position.  相似文献   
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