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71.
72.
N. A. Lee N. C. Rachaputi G. C. Wright S. Krosch K. Norman J. Anderson 《Food and Agricultural Immunology》2005,16(2):149-163
Analytical validation of a competitive direct SUNQuik ELISA with a reference High Performance Liquid Chromatography (HPLC) method and other methods including a minicolumn method and the VICAM Aflatest® system for aflatoxin in peanuts was conducted. Both the ELISA and the VICAM Aflatest® system, using the same peanut extracts were analytically comparable with the HPLC method (R=0.998, p<0.000). The minicolumn method was also found to be acceptable as a low cost rapid semi-quantitative test. Despite the large variation in sampling, the correlation between the SUNQuik ELISA and HPLC using the different peanut sub-samples was considered acceptable over the range of 0–1200 µg kg?1 (R=0.938). No false negatives were found using the SUNQuik ELISA and false positives were either nil or negligible in all the studies conducted. The repeatability of the SUNQuik ELISA run on the same day was good with only±10% deviation. The reproducibility of the SUNQuik ELISA between days was also acceptable, but with a higher deviation. Applying the SUNQuik ELISA for aflatoxin surveys of peanuts in Indonesia proved that the method can deliver high quality, cost- and time-effective analysis with very little establishment capital and maintenance. 相似文献
73.
麻醉剂量羟甲芬太尼对大鼠脑内单胺递质及其代谢物含量的影响金昔陆1唐琴梅金文桥周德和李桂芬池志强(中国科学院上海药物研究所,上海200031)羟甲芬太尼(ohmefentanyl,OMF)是一种新的高选择性高亲和力μ阿片受体激动剂,在动物中能产生麻醉作... 相似文献
74.
呼吸电刺激训练对肺功能康复的作用 总被引:1,自引:1,他引:0
通过电流和声、光信号刺激,对20例慢性阻塞性肺疾患(COPD)患者进行呼吸电刺激训练(RET),结果在RET时呼吸频率和平均吸气流速明显下降,潮气量和吸气间期明显增加,跨膈压增大,氧耗量和能量代谢无明显变化;于RET15天后PaCO2明显下降,PaO2和运动能力明显增高,肺勇气功能明显改善。表明RET15天后PaCO2明显下降,PaO2和运动能力明显增高,肺通气功能明显改善。表明RET能使COPD 相似文献
75.
Electrophysiological examinations were done on 20 patients aged 40–71 years with recently diagnosed high grade non-Hodgkin's lymphomas. General chemotherapy and intrathecal chemotherapy in order to prevent central nervous system (CNS) involvement were begun. On the first day of chemotherapeutic cycle patients received intrathecally methotrexate (ITMTX) and prednisolone. Electrophysiological study was carried out twice in each subject: before ITMTX injection and a day after injection. The study procedure included: a conventional nerve conduction examination (peripheral conduction velocity and compound muscle action potential amplitude), the F wave latency and amplitude measurement and F ratio (F-M-1/2M) calculation for peroneal and tibial nerve bilaterally. Results of the first and the second examinations were statistically compared by t-Student's test. No significant differences between values of estimated parameters were found. The study revealed no recent alterations in proximal, paraspinal motor conduction and motor neuron excitability due to antidromical activation after single ITMTX administration. 相似文献
76.
高频程控增益前置放大器的设计及其在医学仪器中的应用 总被引:1,自引:0,他引:1
目的:设计一种高频程控增益前置放大器,以满足“便携式数字型医用超声声功率计”研究的需要。方法:根据医用超声源频率范围宽、输出功率相差悬殊的特点,权衡便携、低功耗与低失真度、价格等因素,针对不同应用条件,制作出分别由集成电路和分立元件构成的两种结构不同的高频程控增益前置放大器,经调试、优化后,应用到医用超声声功率计中。结果:两种电路分别应用于“便携式数字型医用超声声功率计”,经试用,效果良好。结论:实践证明,由集成电路组成的放大器具有体积小、功耗低、电路结构简单、易与微处理器接口等优点,但它对器件依赖性强,信号保真度差,价格昂贵;而分立元件组成的放大器虽然体积、功耗、与微处理器接口等方面逊于前者,但它元器件易得,信号保真度好,价格低廉。在体积、功耗等条件许可的情况下,该放大器不失为上乘选择。 相似文献
77.
介绍供医用超声功率计用的两种高频、宽增益的小信号放大器,并比较了它们彼此的优缺点。 相似文献
78.
Procedural memory stimulation in Alzheimer's disease: impact of a training programme 总被引:5,自引:0,他引:5
O. Zanetti G. Binetti E. Magni L. Rozzini A. Bianchetti M. Trabucchi 《Acta neurologica Scandinavica》1997,95(3):152-157
The study evaluates the efficacy of a procedural memory stimulation programme in mild and mild-moderate Alzheimer's disease (AD). Twenty basic and instrumental activities of daily living have been selected, and divided into two groups, comparable for difficulty. Ten normal elderly subjects (age 68.0±4.8 years; MMSE score: 28.7±0.9; education: 7.6±3.5 years) were asked to perform the two groups of daily activities and the time required to perform the tasks of each group was recorded and used as a reference. Ten mild and mild-moderate AD patients (age 77.2±5.3 years; MMSE score: 19.8±3.5; education: 7.3±4.7 years) without major behavioural disturbances constituted the experimental group. Patients were evaluated in all 20 daily activities and the time employed was recorded at baseline and after a 3-week training (1 h/d, 5 d/week) period. Five patients were trained during the 3 weeks on half of the 20 daily activities and the other five patients were trained on the remainder. This procedure was adopted in order to detect separately the improvement in "trained" and "not trained" activities, allowing to control better the effects of the intervention. The assessment of the functional impact of the training was directly measured, through the variation of time employed to perform tasks before and after training. After 3 weeks of training a significant improvement was observed for the trained activities, from 3.6 to 1.9 standard deviations below the performance of the normal elderly controls ( P <0.05). AD patients improved also in not-trained activities from 3.5 to 2.7 standard deviations below the controls'performance ( P <0.05). The rehabilitation of activities of daily living through developing procedural memory strategies may be effective in mild and mild-moderate AD patients. 相似文献
79.
We studied nine cases of retrobulbar neuritis with confirmed multiple sclerosis and six cases of optic atrophy from other causes. Pattern and focal electroretinograms (macular ERGs) were recorded with high (400 cd/m2) and low (40 cd/m2) intensity stimuli. Contrast sensitivity was also measured with a simple printed test.Luminance was not markedly important. High spatial frequency contrast sensitivity was significantly correlated with pattern ERG amplitude. Pattern and focal ERG amplitude ratio was usually reduced, but the effect was not correlated with contrast sensitivity or large enough to be useful clinically.In optic atrophy the pattern ERG (PERG) was clearly more severely reduced than the focal ERG (FERG). In retrobulbar neuritis both ERGs were equally and more severely reduced even though the visual losses were less. In unilateral cases the PERG increased then decreased after the initial attack, as previously described (Arden et al., 1982). The results suggest that retinal layers beyond the ganglion cells may be affected in retrobulbar neuritis, but proximally generated, pattern-specific ERG components are selectively lost in optic atrophy. 相似文献
80.
Charlotte A. Hazel 《Clinical & experimental optometry》1995,78(3):98-105
For years it has been recognised that many sports place demands on vision and particular visual skills. There is much evidence to show that the correction of visual dysfunction such as ametropia and binocular and accommodative anomalies results in improved sporting performance for those sports. More controversial and of special interest is the suggestion that it is possible to train visual abilities of subjects who do not present with traditionally recognised functional disorders of vision. It has been proposed that sporting performance can be improved as a result of this training. However, this review found the evidence to be inconclusive. In addition, there are studies that suggest athletes have better visual abilities than non-athletes and good athletes have better abilities than less skilled athletes. However, it has not been determined whether these superior abilities are innate to the athlete or have developed through practice. A review of the available literature was unable to prove (or disprove) either of these proposals. However, there appears to be enough evidence to warrant further investigation of these questions, in order that the area of sports vision and vision training can be more fully understood. This will enable clinicians to take full advantage of the potential of sports vision practice to assist athletes. (Clin Exp Optom 1995; 78: 3: 98–105) 相似文献