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91.
The authors present the third installment of the guidelines and recommendations from the Safety Committee of the Society for Magnetic Resonance Imaging (now the Society of Magnetic Resonance) concerning various issues related to the safety and management of patients undergoing magnetic resonance (MR) procedures. This document was developed to provide standardized and consistent information for use by health practitioners involved in screening patients or other individuals for MR procedures.  相似文献   
92.
    
A knowledge-based alarm system for intensive care monitoring was designed, built, tested on-line, and evaluated. The system is a functional prototype of a highly specific patient monitor providing alarms on hypovolemia, hyperdynamic state, left ventricular failure and hypoventilation. These intelligent alarm functions aim to maintain the quality of patient monitoring even if nurses' attention is temporarily reduced or focused elsewhere. The alarm system has an electronic access to data available in a multichannel patient monitor and the patient data management system of the intensive care unit. Median filtering, trend estimation, and rule-based reasoning are applied when processing the measured variables and estimating the patient's state.  相似文献   
93.
微型无线收发器在中央监护系统中的应用   总被引:3,自引:0,他引:3  
中央监护系统能够实现对病人的生理或生化参数连续、长时间、自动、实时监测,并经分析、处理后实现多类别自动报警、自动记录及对诊断结果进行综合判断等。传统的多参数生理监护系统主要是通过各种专用电缆来实现网络化,在增加产品成本的同时也加大了施工的难度。本文在分析了无线收发芯片XE1201的工作原理基础上,重点介绍了应用其开发无线收发模块的原理和方法,并利用此模块构建了无线中央监护系统,继而对整个系统的性能进行了测试。该系统已在实验室中实现,并对心电(ECG)、无创血压、血氧饱和度(SPO2)等多生理参数进行实时监护,将信息提供给医院内的网络,以供访问使用。  相似文献   
94.
1999~2001年全国治疗药物监测室间质评结果   总被引:1,自引:0,他引:1  
郭健  陆红  谢洁红 《中国医药导刊》2002,4(3):229-230,228
目的:通过开展室间质量评价活动提高临床实验室的检验结果质量。方法:每年向参加治疗药物监测(TDM)室间质量评价活动的单位发放质控品10个批号,测定项目包括茶碱、地高辛、苯妥英、苯巴比妥、卡马西平和环孢菌素A,实验室用常规方法测定并回报测定结果,经计算机软件对全部结果进行统计分析。结果:2001年参加TDM室间质评的实验室数为48家,测定结果的平均及格率分别为茶碱94.2%、地高辛82.6%、苯妥英83.8%、苯巴比妥88.4%、卡马西平94.2和环孢菌素A92.4%。1999~2001年全国TDM室间质评的年平均及格率分别为78.7%、84.7%和89.3%。不同测定方法的精密度分别为茶碱4.4%~14.2%、地高辛11.5%~21.9%、苯妥英8.5%~29.5%、苯巴比妥8.2%~13.9%、卡马西平10.8%~12.6%和环孢菌素A15.5%~16.6%。结论:多数参加TDM室间质评实验室的测定结果有较好的一致性,及格率逐年上升,但参加TDM室间质评的实验室数占开展TDM的实验室总数的比例较低,在不同的测定方法间还存在较大的差异。  相似文献   
95.
Occupational exposure to carcinogenic agents on the decks on six Norwegian crude oil tankers was examined in five harbors. The purpose of the study was to evaluate the need for improving the working environment on deck on these tankers. Technical arrangments and the work itself on the deck were observed during loading or unloading. Occupational monitoring was performed by active sampling of benzene, polyaromatic hydrocarbons, and some aldehydes. The crew answered a questionnaire concerning their work, use of protective equipment, and occurrence of acute symptoms. The levels of air-borne carcinogenic agents were low, probably due to closed loading systems on all tankers. However, the seamen reported discomfort during the work that may be related to other chemical agents in the cargo. The seamen were frequently painting with lead chromate paint without using personal protective equipment. This type of chemical exposure should be evaluated.  相似文献   
96.
Since cyclosporin A (CsA), a widely used immunosuppressive drug, strongly suppresses interleukin-2 (IL-2) secretion, it is frequently difficult to estimate T lymphocyte activation in early acute rejection. We found that, when evaluated based on HLA-DQ antigen expression, monocyte activation in the peripheral blood of renal transplantation patients was a very sharp parameter in diagosing acute rejection. All of 16 episodes of early acute rejection, which were relatively easily suppressed by steroid pulse therapy, showed a sharp increase in the proportion of HLA-DQ antigen-positive monocytes (DQ+ mono) and a quick return of DQ+ mono to previous values, along with a fall in serum creatinine levels. Since, however, HLA-DR antigen-positive T lymphocytes (DR +T) were markedly increased over a long period in episodes of therapy-resistant and chronic rejection, their prolonged high value was regarded as a parameter indicative of poor prognosis.  相似文献   
97.
The mapping of 5-HT2 receptors in the brain using functional imaging techniques has been limited by a relative lack of selective radioligands. Iodine-123 labelled 4-amino-N-[1-[3-(4-fluorophenoxy)propyl]-4-methyl-4-piperidinyl]-5-iodo-2-methoxybenzamide (123I-5-I-R91150 or123I-R93274) is a new ligand for single-photon emission tomography (SPET), with high affinity and selectivity for 5-HT2A receptors. This study reports on preliminary123I-5-I-R91150 SPET, wholebody and blood distribution findings in five healthy human volunteers. Maximal brain uptake was approximately 2% of total body counts at 180 min post injection (p.i.). Dynamic SPET sequences were acquired with the brain-dedicated, single-slice multi-detector system SEM-810 over 200 min p.i. Early peak uptake (at 5 min p.i.) was seen in the cerebellum, a region free from 5HT2A receptors. In contrast, radioligand binding in the frontal cortex increased steadily over time, up to a peak at approximately 100–120 min p.i. Frontal cortex-cerebellum activity ratios reached values of 1.4, and remained stable from approximately 100 min p.i. onwards. Multi-slice SPET sequences showed a pattern of regional variation of binding compatible with the autoradiographic data on the distribution of 5-HT2A receptors in (cerebral cortex>striatum>cerebellum). These findings suggest that123I-5-I-R91150 may be used for the imaging of 5-HT2A receptors in the living human brain with SPET.  相似文献   
98.
测定115例足月妊娠者(正常妊娠62例,高危妊娠53例)脐动脉血流速波(UmAS/D),同时作产前胎心电子监护(NST),其中37例于分娩时抽取脐动脉血作血气分析。对上述三种方法预测新生儿结局的效果进行比较。结果表明:UmAS/D、脐动脉血的pH值较NST对新生儿结局不良有较好的预测性,异常UrnAS/D与新生儿酸中毒有密切关系。  相似文献   
99.
The torque-angular deformation in right axial rotation until failure of the ligamentous occipito-atlanto-axial complex subjected to variable loading rate (dynamic) axial torque was characterized using a biaxial MTS system. A special fixture and gear box that permitted right axial rotation of the specimen until failure without imposing any additional constraints were used to obtain the data. The specimens were divided into three groups and tested until failure at three different dynamic loading rates: 50, 100, and 400 degrees/s. A previous study by the authors provided data for quasi-static (4 degrees/s) loading conditions. The torque versus rotation curves can be divided into two straight regions and two transition zones. The plots clearly indicated that at loading rates higher than 4 degrees/s, the specimens became stiffer in the region of steadily increasing resistance prior to failure. The increase in stiffness was maximum at 100 degrees/s. The stiffness decreased somewhat at 400 degrees/s in comparison with 100 degrees/s, but this decrease was not significant. The resulting torque-right axial rotation curves were also examined to estimate the magnitude of maximum resistance (torque) and the corresponding angular rotation value. The average maximum resistance torque increased from 13.6 Nm at 4 degrees/s to 27.8 Nm at 100 degrees/s. The corresponding right angular rotation data (65-78 degrees), however, did not show any significant variation with loading rate. Posttest dissection of the specimens indicated that the type of injury observed was related to the rate of axial loading imposed on a specimen during testing.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
100.
江门市乡镇集中式供水卫生现状分析   总被引:1,自引:0,他引:1  
为加强乡镇集中式供水卫生管理,进一步普及与提高农村的改水工作,我们按统一的调查方案,于1994 ̄1995年在全国范围内开展乡镇自来水厂调查登记和水质监测工作。据统计全市建成投产乡镇水厂68座,普及率77.3%,受益人口149.09万,占农村总人口62.5%,调查结果显示,水源总污染率为8.82%,在监测项目中主查细菌学指标合格率不高,丰、枯水期水源水平均合格率分别为40.0%和88.9%,而出厂水  相似文献   
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