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排序方式: 共有1421条查询结果,搜索用时 15 毫秒
1.
静脉输液滴速自动显示仪的研制 总被引:3,自引:3,他引:0
本文介绍了该产品基于数字电路和基于单片机ATMEL89C2051两种方案软硬件设计。能够正确显示静脉输液滴数,方便患者和减轻陪护人员的负担,并且在无药液和血管堵塞两种情况下,自动报警。在输液过程中,发光二极管同步显示液滴滴速快慢的变化。 相似文献
2.
便携式多普勒血管探测仪在皮瓣移植中的应用 总被引:3,自引:0,他引:3
目的 :研究皮瓣移植前简单、可靠的血管探测的方法。方法 :在皮瓣移植前 ,以 HADECO ES-1 0 0 0 SPM多普勒血管探测仪对皮瓣血管蒂及皮动脉进行探测 ,与术中皮动脉探查结果进行比较 ,考察术前血管探测的准确性和意义。结果 :皮瓣血管蒂及皮动脉术前探测与术中探查结果完全一致。结论 :便携式血管多普勒仪是皮瓣移植前 ,简单、可靠的血管探测的仪器 ,根据探测结果进行皮瓣设计 ,有效地降低了手术失败的风险 相似文献
3.
大鼠脑内儿茶酚胺类递质及其代谢物的同时提取及反向高效液相测定法 总被引:3,自引:0,他引:3
目的建立一种操作简便、高效的测定脑组织中去甲肾上腺素(NA)、肾上腺素(AD)、多巴胺(DA)、3,4二羟基苯乙酸(DOPAC)及高香草酸(HVA)的方法,为有关药物作用机理的研究提供实验手段.方法以有机溶剂提取,高效液相色谱--电化学检测器(HPLC-EC)测定大鼠纹状体、皮质、下丘脑NA、AD、DA、DOPAC及HVA的含量.结果测得NA、AD、DA、DOPAC及HVA的绝对回收率依次分别为:80.3%±12.4%,86.5%±14.3%,90.3%±12.1%,89.5%±17.2%、87.6%±[13].2%.线性范围0.2~20ng,批内与批间变异系数分别小于8%及10%.结论该方法具有简便、迅速、回收率较高的特点,便于实验室应用. 相似文献
4.
A. I. Tew 《Medical & biological engineering & computing》1988,26(1):68-74
For some disabled people pointing provides a more convenient means of communication and control than the use of switches.
The quadriplegic who retains good control of head movement can be provided with a number of input alternatives, but no existing
system meets all the requirements of a general-purpose electronic pointing device. Consequently the Oxford Optical Pointer
has been developed. The principle by which it converts relative direction into analogue electrical signals is described and
its application as a head-mounted device for controlling an electric wheelchair is presented. 相似文献
5.
目的:确定多层螺旋CT肝门静脉系统检查的合理延迟时间及双通路注射对比剂法的可行性。方法:分为2个步骤研究:①随机选择无腹部及心血管疾患的患者53例,以3 ml/s速率注射造影剂20 ml,行同层动态扫描,计算腹主动脉、肝门静脉、下腔静脉、肝实质的对比剂时间密度曲线,及它们的相关性。②47例需门静脉检查的患者,行MDCT肝区移床式、动态扫描,在右肘部静脉及下肢静脉同时注入对比剂,对比剂总量1.5~2 ml/kg。扫描时使用对比剂自动示踪软件,设动脉血管阈值为120 HU启动扫描,动脉期扫描完成后延时20.1±5.54 s行门静脉扫描,分别评价肝门静脉、肝静脉、下腔静脉的显示率及程度。结果:①20 ml对比剂注射同层动态扫描肝门层面腹主动脉达峰时间为18.5±4.81 s,肝门静脉达峰时间是38.61±6.59 s,下腔静脉达峰时间是55.44±12.16 s,肝实质的达峰时间是56±5.7 s。②肝门静脉显示率达100%,肝门静脉主干等显示程度平均评分2.50~2.93;相关小分支静脉显示率为87%~98%,显示平均评分2.25~2.63。结论:MDCT右肘部静脉及下肢静脉同时注入对比剂,在动脉期扫描完成后,延时20.1±5.54 s行肝门静脉检查,肝门静脉系统成像效果良好。 相似文献
6.
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
7.
Changes in blood lactate and respiratory gas exchange measures in sports with discontinuous load profiles 总被引:2,自引:0,他引:2
Smekal G von Duvillard SP Pokan R Tschan H Baron R Hofmann P Wonisch M Bachl N 《European journal of applied physiology》2003,89(5):489-495
This study compares two different sport events (orienteering = OTC; tennis = TEC) with discontinuous load profiles and different
activity/recovery patterns by means of blood lactate (LA), heart rate (HR), and respiratory gas exchange measures (RGME) determined
via a portable respiratory system. During the TEC, 20 tennis-ranked male subjects [age: 26.0 (3.7) years; height: 181.0 (5.7) cm;
weight: 73.2 (6.8) kg; maximal oxygen consumption (V˙O2max): 57.3 (5.1) ml·kg−1·min−1] played ten matches of 50 min. During the OTC, 11 male members of the Austrian National Team [age: 23.5 (3.9) years; height:
183.6 (6.8) cm; weight: 72.4 (3.9) kg; V˙O2max: 67.9 (3.8) ml·kg−1·min−1] performed a simulated OTC (six sections; average length: 10.090 m). In both studies data from the maximal treadmill tests
(TT) were used as reference values for the comparison of energy expenditure of OTC and TEC. During TEC, the average V˙O2 was considerably lower [29.1 (5.6) ml·kg−1·min−1] or 51.1 (10.9)% of VO2max and 64.8.0 (13.3)% of V˙O2 determined at the individual anaerobic threshold (IAT) on the TT. The short high-intensity periods (activity/recovery = 1/6)
did not result in higher LA levels [average LA of games: 2.07 (0.9) mmol·l−1]. The highest average V˙O2 value for a whole game was 47.8 ml·kg−1·min−1 and may provide a reference for energy demands required to sustain high-intensity periods of tennis predominately via aerobic
mechanism of energy delivery. During OTC, we found an average V˙O2 of 56.4 (4.5) ml·kg−1·min−1 or 83.0 (3.8)% of V˙O2max and 94.6 (5.2)% of V˙O2 at IAT. In contrast to TEC, LA were relatively high [5.16 (1.5) mmol·l−1) although the average V˙O2 was significantly lower than V˙O2 at IAT. Our data suggest that portable RGEM provides valuable information concerning the energy expenditure in sports that
cannot be interpreted from LA or HR measures alone. Portable RGEM systems provide valuable assessment of under- or over-estimation
of requirements of sports and assist in the optimization and interpretation of training in athletes.
Electronic Publication 相似文献
8.
Donald A. Czech 《Physiology & behavior》1982,29(6):1179-1181
An casuy constructed and inexpensive drop-sensing drinkometer is described, which incorporates an integrated circuit photodetector. It provides a reliable and convenient means of automatically monitoring fluid intake in a number of experimental situations. The animal is undisturbed and isolated from the electrical system components. 相似文献
9.
Tsutomu Gomi Kichirou Koshida Tosiaki Miyati Jun Miyagawa Hiroshi Hirano 《Journal of digital imaging》2006,19(4):362-370
The purpose of this work was to compare direct and indirect detectors in terms of their system linearity, presampled modulation
transfer function (MTF), Wiener spectrum (WS), noise equivalent quanta (NEQ), and power spectrum. Measurements were made on
two flat-panel detectors, GE Revolution XR/d (indirect) and Shimadzu Safire (direct) radiographic techniques. The system linearity
of the systems was measured using a time-scale method. The MTF of the systems was measured using an edge method. The WS of
the systems was determined for a variable range of exposure levels by two-dimensional Fourier analysis. The NEQ was assessed
from the measured MTF, WS, and estimated ideal signal-to-noise ratios. Power spectrum analyzed the chest phantom within artificial
lesions. System linearity was excellent for the direct systems. For the direct system, the MTF was found to be significantly
higher than that for the indirect systems. For the direct system, the WS was relatively uniform across all frequencies. In
comparison, the indirect system exhibited a drop in the WS at high frequencies. At lower frequencies, the NEQ for the indirect
system was noticeably higher than for the direct system. Power spectrum for the direct system was relatively flat and similar
to that for white noise. The indirect system exhibited significant reduction at high spatial frequencies. In general, the
direct systems exhibit improved image quality over indirect systems at comparable exposure dose. 相似文献
10.
目的:目前,国内X(γ)刀的国家检定规程正在起草之中,本文的目的是为X(γ)刀剂量测量提供合理的设备与吸收剂量计算方法。材料与方法:利用德国PTW-UNIDOS剂量仅与有效体积为0.015cc的针尖电离室及自制的小体积半导体探测器相匹配,在160mm直径的有机玻璃球形模体内测量X(γ)刀的输出吸收剂量,并验证其治疗计划的实际输出剂量,得到较满意的结果。结论:为了保证剂量的准确度,X(γ)刀治疗计划系统的实际输出剂量应定期在现场测量与验证,所用探测器的直径应小于射野直径的1/2,小灵敏体积的半导体探测器适宜X(γ)刀小野(如:Ф4mm)的测量。 相似文献