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1.
2.
This study utilizes a psychophysical approach to examine the effects on
carrying capacity for bi-manual carrying tasks involving different handle positions and
carrying ranges. A total of 16 female subjects participated in the experiment in groups of
two people, and each group of subjects performed the tasks in a random order with 12
different combinations of carrying task. The independent variables are handle position
(upper, middle, lower) and carrying range (F–F: floor height carried to floor height, F–W:
floor height carried to waist height, W–W: waist height carried to waist height, W–F:
waist height carried to floor height), the dependent variable is the maximum acceptable
carried weight (MAWC), heart rate (HR), and the rating of perceived exertion (RPE). The
results show that the handle position has a significant effect on MAWC and overall RPE but
no significant effect on HR. Carrying range has a significant effect on the MAWC and HR,
but no significant effect on overall HR. The handle position and carrying range have a
significant interaction on the MAWC and HR. The RPE for different body parts shows
significant differences, and the hands feel the most tired. Overall, this study confirms
that the lower handle position with the W–W carrying range is the best combination for a
two-person carrying task. 相似文献
3.
Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence. 相似文献
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目的研究正常人眼球运动动态磁共振成像(MRI)4条直肌Pulley(滑车)的功能性位置。方法采用西门子公司Sonata1.5T超导型MRI扫描仪,应用眼球运动动态MRI技术,获取20名正常人(20个眼眶)眼球原在位及上转、下转、内转、外转20度时垂直于眶轴的眼眶冠状位MRI图像。以眼球中心为原点建立三维坐标系,应用ScionImage医学图像测量软件分别测量各层面眼球垂直转动时水平直肌、眼球水平转动时垂直直肌的横截面质心。根据各层面直肌横截面质心的坐标值建立直线回归方程,分别求得眼球垂直转动时内、外直肌径路及眼球水平转动时上、下直肌径路直线回归曲线斜率变化最大的一点,即为该直肌Pulley的功能性位置。对4条直肌Pulley相对于眼球中心的坐标值(X、Y)进行统计。结果内直肌Pulley位于眼球中心后4mm,内14.7mm,下0.3mm;外直肌Pulley位于眼球中心后8mm,外9.8mm,下0.3mm;上直肌Pulley位于眼球中心后6mm,内1.6mm,上11.5mm;下直肌Pulley位于眼球中心后6mm,内4.4mm,下12.7mm。结论应用眼球运动动态MRI技术,分析眼球转动时直肌径路的变化,可证实4条直肌Pulley的存在并确定其功能位置。 相似文献
8.
We compared the Acrysoft monofocal intraocular lens (IOL) in the mini monovision formula (n = 20) with the Array multifocal intraocular lens (n = 20) for glasses independence after cataract surgery. The Acrysoft monofocal IOL group showed similar and even slightly
better results than the Array multifocal IOL group. The monofocal Acrysoft IOL using the mini monovision (blended vision)
formula is a good alternative for providing post-cataract surgery glasses independence.
Drs. Chen, Clinical Assistant Professor of Ophthalmology and Neal H. Atebara are at University of Hawaii School of Medicine,
Honolulu, Hawaii, USA.
Dr. Te Tsaw Chen, Past Professor & Director, was at Department of Ophthalmology, Taipei Medical University, Taipei, ROC.
The authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer
or provider of services discussed in this article. The authors also do not discuss the use of off-label products, which includes
unlabeled, unapproved, or investigative products or devices.
The authors compared the Acrysoft monofocal intraocular lens in the mini monovision formula to the Array multifocal intraocular
lens for glasses independence after cataract surgery. 相似文献
9.
Jen Te Hsu Chi Ming Chu Shih Tai Chang Hui Wen Cheng Nye Jan Cheng Wan-Ching Ho Chang Min Chung 《Circulation journal》2006,70(12):1611-1616
BACKGROUND: This study investigated the utility of the alveolar - arterial oxygen pressure difference (AaDO (2)) in predicting the short-term prognosis of acute pulmonary embolism (PE). METHODS AND RESULTS: This study retrospectively enrolled 114 consecutive patients with acute PE, diagnosed by either spiral computed tomography or high probability ventilation - perfusion lung scans. During the first 24 h of admission, all patients had initial artery blood gas collected under room air. Patient exclusion criteria were chronic lung disease, septic emboli, and moderate and low probability lung scans. Patients were assigned to 2 groups based on either 30-day death or a 30-day composite event. Receiver operating characteristic analyses was used to determine the AaDO(2) cut-off value for predicting primary and composite endpoints. Statistical analysis demonstrated significant differences in AaDO(2) between the 30-day composite endpoint group and the 30-day composite event-free survival group (p=0.012). The AaDO(2) had a strong trend between the 30-day death group and the survival group (p=0.062). The best cut-off value for AaDO(2) was 53 mmHg and using this, the positive predictive value for 30-day death was 25% and the negative predictive value was 92%. For the 30-day composite endpoint, the positive predictive value for AaDO(2) was 35%, and the negative predictive value was 84%. In this study, thrombocytopenia was also an indicator of poor prognosis for patients with acute PE. CONCLUSION: The AaDO(2) measurement is a highly useful and simple measurement for predicting short-term prognosis in patients with acute PE. It has high negative predictive value and moderate positive predictive value for 30-day death and 30-day composite event. Aggressive thrombolytic treatment strategies should be considered for patients with an initial poor prognostic parameter (ie, AaDO(2) >or=53 mmHg). 相似文献
10.
Noninvasive metabolic magnetic resonance (MR) imaging reflecting glucose metabolism in the aldose-reductase-sorbitol (ARS) pathway was performed in the rabbit head; after administration of the fluorinated glucose analogue 3-fluoro-3-deoxy-D-glucose (3FD-glucose), fluorine-19 images were generated. Images of 3FD-glucose showed significant 3FD-glucose uptake by adipose tissue, indicating its buffering effects in case of excess loads of glucose. Images of 3-fluoro-3-deoxy-D-sorbitol (3FD-sorbitol) demonstrated the spatial distribution of aldose reductase activities and significant sorbitol accumulation in the lens. Images of 3-fluoro-3-deoxy-D-fructose (3FD-fructose) showed preferential uptake of fructose by muscle tissue. The extremely low toxicity of 3FD-glucose indicates promise for its clinical application in metabolic imaging. 相似文献