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Yu Wang Lezheng Wu De-Zheng Wu Futian Jiang Taiqing Luo National Ophthalmological Laboratories Ministry of Public Heallth China Zhongshan Ophthalmic Center Sun Yat-sen University of Medical Sciences Guangzhou China Shaoyu Sheng Zengxi Li Yechen Liang Guangdong lnstitute of Analysis Xianlie Road Guangzhou China 《眼科学报》1992,8(3):131-137
Visual functions and nutrition metabolic characteristics werestudied in 8 subjects(16 eyes)with tobacco-toxic optic neuropathy(TTON).Their visual functions tested by psychophysical and electrophysiologicmethods showed that:1.central vision diminished in 16 eyes,2.dyschromatopsias were found in 14 tested eyes,3.bilateral symmetricalcentral or cecocentral scotomas were the visual field characteristics in allcases,4.PVEP were severe abnormal in 3 spatial frequencies in all cases and56.3% of 15‘ checkboard ... 相似文献
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D. Kyroussis G. H. Mills M. I. Polkey C. H. Hamnegard S. Wragg J. Road M. Green J. Moxham 《Thorax》1996,51(5):510-515
BACKGROUND: When the demand placed on the respiratory system is increased, the abdominal muscles become vigorously active to achieve expiration and facilitate subsequent inspiration. Abdominal muscle function could limit ventilatory capacity and a method to detect abdominal muscle fatigue would be of value. The maximum relaxation rate (MRR) of skeletal muscle has been used as an early index of the onset of the fatiguing process and precedes failure of force generation. The aim of this study was to measure MRR of abdominal muscles and to investigate whether it slows after maximum isocapnic ventilation (MIV). METHODS: Five normal subjects were studied. Each performed short sharp expiratory efforts against a 3 mm orifice before and immediately after a two minute MIV. Gastric pressure (PGA) was recorded and MRR (% pressure fall/10 ms) for each PGA trace was determined. RESULTS: Before MIV the mean (SD) maximum PGA MRR for the five subjects was 7.1 (0.8)% peak pressure fall/10 ms. Following MIV mean PGA MRR was decreased by 30% (range 25-35%), returning to control values within 5-10 minutes. CONCLUSIONS: The MRR of the abdominal muscles, measured from PGA, is numerically similar to that described for the diaphragm and other skeletal muscles. After two minutes of maximal isocapnic ventilation abdominal muscle MRR slows, indicating that these muscles are sufficiently heavily loaded to initiate the fatiguing process. 相似文献
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Chronic obstructive pulmonary disease (COPD) is a respiratory disease that results in airflow limitation and respiratory distress. The effects of COPD, however, are not exclusively limited to respiratory function and people with COPD face many non-respiratory manifestations that affect both function and mobility. Deficits in function and mobility have been associated with an increased risk for falling in older adults. The purpose of this study was to provide a theoretical framework to identify risks factors for falls in people with COPD. We have analyzed the literature to identify possible relationships between pathophysiological changes observed in COPD and common risk factors for falls. Well-established fall risk factors in people with COPD include lower limb muscle weakness and impaired activities of daily living. Other intrinsic risk factors such as gait and balance deficits, nutritional depletion, malnutrition, depression, cognitive impairments and medications are possible risk factors that need to be confirmed with more studies. There is no evidence that visual deficits are common in COPD. The role that precipitating factors such as syncope and postural hypotension may have on fall risk is unclear. Exacerbations and dyspnea do not have a precipitating effect on fall risk but they contribute to the progressive physical deterioration that may theoretically increase the risk for falls. While these results suggest that people with COPD might have an increased susceptibility to fall compared to their healthy peers, further research is needed to determine the prevalence of falls and specific risk factors for falls in people living with COPD. 相似文献
88.
Tong Zhang Ya-Zhong Zhang Jian-Sheng Tao College of Chinese Materia Medica Shanghai University of Traditional Chinese Medicine Cai-Lun Road Shanghai China 《Journal of Asian natural products research》2013,15(5):479-485
Bioassay-guided fractionation led to the isolation of eight compounds from Stemona sessilifolia. Of the eight isolates, three new bibenzyls, stilbostemins M–O (1–3), and a new tocopherol, 6-methoxy-3,4-dehydro-δ-tocopherol (4) were revealed together with four known compounds 3,5-dihydroxy-2′-methoxy bibenzyl (5), 3,5-dihydroxy bibenzyl (6), β-tocopherol (7), and γ-tocopherol (8). Compounds 5, 6, and 8 exhibited strong antibacterial activities against Staphylococcus aureus and S. epidermidis. 相似文献
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Sherman MF Road JD McKenzie DC Sheel AW 《Physiologie appliquee, nutrition et metabolisme》2011,36(6):821-830
The objective of this study was to measure the magnitude of the muscle metaboreflex in people with chronic obstructive pulmonary disease (COPD) compared with healthy controls and to assess the relationships between disease severity, exercise capacity, and the magnitude of the muscle metaboreflex. Nine people with mild-to-severe COPD and 11 age- and gender-matched healthy controls performed isometric handgrip exercise (IHG), followed by postexercise circulatory occlusion (PECO) while hemodynamic changes were measured. Continuous measures of heart rate, arterial pressure, leg blood flow, leg vascular resistance, and total peripheral resistance were obtained. Participants then performed a cycle test to exhaustion. Heart rate, blood pressure, and blood flow responses during IHG and PECO were similar between the COPD group and healthy controls (p > 0.05). There was no association between disease severity or exercise capacity and the magnitude of the muscle metaboreflex. We observed a preserved muscle metaboreflex in mild-to-severe COPD, suggesting the metaboreflex is not a contributing factor to the development of exercise intolerance in this population. 相似文献
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