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41.
徐湘盛  封黎明 《蛇志》1991,3(3):43-44
本文通过116例二尖瓣决窄分离术中监护和输液,从中体会到术中监护是心脏手术成功必不可少的条件。只有做好术中监护,才能及时了解病情发展,正确指导复苏和输液,提高手术的安全系数。  相似文献   
42.
An account is given of the use of Enteromorpha to monitor zinc, cadmium, mercury and lead pollution in six estuaries and the British North Sea coast. The ranges for each element were: Zn, 19–437 µg g–1; µg g–1 Cd, 0.07–4.8 µg g–1; Hg, 0.02–0.23 µg g–1. It is suggested that tissue analysis of Enteromorpha is one of the most useful biological techniques available in estuaries for pin-pointing aqueous (as opposed to sediment) metal contamination, and also for providing data suitable for world-wide comparisons. Provisional values are given for concentrations corresponding to moderate and high pollution.Deceased  相似文献   
43.
正Monitoring.We,ecologists,hear the word nearly every day.From the most unexpected corners this word springs out,much used and abused.One one hand,it is often used by my peers to justify their work,their project or even their existence as scientists.They claim to do useful work,because they monitor some phenomenon or another.This,goes the ar-  相似文献   
44.
药用植物是中药资源的重要组成部分,设计调查方法是资源调查的前提,合理的调查方法需充分结合调查对象的特点及调查预期目标。本文通过概述我国野生与栽培药用植物的特点及开发利用中的问题,分析传统药用植物调查方法的适用性及高光谱遥感与“5S”集成技术在药用植物资源调查中的应用价值。实现药用植物资源从掌握资源总量向监控资源整体的跨越式转变对我国中药事业现代化及可持续发展具有重要意义,建立资源监控机制要求调查方法的高效率与高准确性,并可长期运作,建立卫星遥感动态监测平台与中药现代化产业统计报表制度作为我国药用植物资源整体监控机制具有较大应用前景。  相似文献   
45.
At PSI (Paul Scherrer Institute), Switzerland, a superconducting cyclotron called “COMET” delivers proton beam of 250 MeV pulsed at 72.85 MHz for proton radiation therapy. Measuring proton beam currents (0.1–10nA) is of crucial importance for the treatment safety and is usually performed with invasive monitors such as ionisation chambers (ICs) which degrade the beam quality. A new non-invasive beam current monitor working on the principle of electromagnetic resonance is built to replace ICs in order to preserve the beam quality delivered. The fundamental resonance frequency of the resonator is tuned to 145.7 MHz, which is the second harmonic of the pulse rate, so it provides signals proportional to beam current. The cavity resonator installed in the beamline of the COMET is designed to measure beam currents for the energy range 238–70 MeV. Good agreement is reached between expected and measured resonator response over the energy range of interest. The resonator can deliver beam current information down to 0.15 nA for a measurement integration time of 1 s. The cavity resonator might be applied serving as a safety monitor to trigger interlocks within the existing domain of proton radiation therapy. Low beam currents limit the abilities to detect sufficiently, however, with the potential implementation of FLASH proton therapy, the application of cavity resonator as an online beam-monitoring device is feasible.  相似文献   
46.
An Insect Activity Monitor was created to measure the behavioural responses of fleas (Siphonaptera). The apparatus allows for a range of visual, chemo- and mechanoreceptor cues to be presented. The jumping response is detected by counting amplified pulses produced as the fleas land on a stretched membrane held over a microphone. Horizontal movements are detected using a system of infra-red beams and phototransistors which, when broken, are counted as a measure of activity. The apparatus was tested using Ceratophyllus hirundinis (Curtis), Ceratophyllus farreni (Rothschild) and Ceratophyllus rusticus (Wagner), co-inhabiting species from the nests of the house martin (Delichon u.urbica L.). No unaided emigration or immigration has been demonstrated in these species (Clark, 1988) and much of their time is spent confined to the darkness of the nest. In addition to species contrasts, females were more active than males and fleas were more active at 25 degrees C than at 18 degrees C. The more active bird flea Ceratophyllus garei (Rothschild) from the nest of pheasant (Phasianus colchicus L), was tested for responses to light of varying intensity. Activity was stimulated by white light, but not proportional to light intensity.  相似文献   
47.
The exposure of the general population to benzene   总被引:6,自引:0,他引:6  
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48.
研制出一种简单实用、安全可靠并具有广阔市场前景的袖珍式胎心音仪。该仪器利用超声多普勒原理,用超声探头从母体腹部提取胎儿心音信号,经过信号解调及低频放大、音频功率放大等处理,然后由耳机及扬声器输出胎心音。  相似文献   
49.
目的探索建立利用微卫星遗传标记对中国恒河猴免疫遗传学同质性分群的方法。方法根据已报道的中国恒河猴和印度恒河猴微卫星标记和与MHC基因高度连锁的微卫星遗传标记,对52只恒河猴进行了微卫星检测和遗传同质性分群。结果依据判断标准,可以将检测的恒河猴分为印度恒河猴,中国恒河猴和无法判定来源的恒河猴3个地理类别,并根据MHC附近的微卫星遗传标记将其分为若干MHC基因相同的同质性群体。结论此方法的建立将有利于恒河猴参与的实验分组,也为恒河猴繁殖管理提供了参考。  相似文献   
50.
活细胞量是与细胞生长、代谢、生产力相关的重要生理参数。在线活细胞测定仪能够利用电容的原理检测发酵液中的活细胞量。本文详细介绍了国产在线活细胞测定仪的检测原理,并说明了其在毕赤酵母发酵过程中的应用情况。结果表明,我们设计的在线活细胞测定仪能够直接、实时、在线获得发酵过程中可靠的活细胞量,且有效避免采样操作的干扰。这一技术符合过程分析技术(PAT)的要求,并可以与其他参数相结合进行分析,作为发酵过程开发、控制和优化的有利工具。  相似文献   
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