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71.
不同剂量瑞芬太尼复合靶控输注异丙酚对心脏瓣膜置换术病人气管插管时血液动力学反应的影响 总被引:1,自引:0,他引:1
目的 评价不同剂量瑞芬太尼复合靶控输注(TCI)异丙酚对心脏瓣膜置换术病人气管插管时血液动力学反应的影响.方法 拟行心脏瓣膜置换术的风湿性心脏病病人30例,随机分为3组(n=10):芬太尼组(Ⅰ组)、小剂量瑞芬太尼组(Ⅱ组)和大剂量瑞芬太尼组(Ⅲ组).麻醉诱导:Ⅰ组静脉注射芬太尼10 μg/kg,然后持续静脉输注芬太尼10 μg·kg-1·h-1;Ⅱ组和Ⅲ组静脉注射瑞芬太尼1μg/kg,然后分别持续静脉输注瑞芬太尼0.5、1.0 μg·kg-1·min-1.3组静脉注射芬太尼或瑞芬太尼后3min开始TCI异丙酚,初始血浆靶浓度为1.0 μg/ml,逐渐递增至2.0 μg/ml.静脉注射罗库溴铵0.6 mg/kg后气管插管.分别在麻醉诱导前(T0)、诱导期间血压最低值时(T1)、插管前即刻(T2)、插管后1 min(T3)、插管后2 min(T4)及插管后5 min(T5)时记录心率(HR)、平均动脉压(MAP)、中心静脉压(CVP)、肺毛细血管楔压(PCWP)、心脏指数(CI)、外周血管阻力指数(SVRI)及左室每搏功指数(LVSWI),并于上述时点测定混合静脉血氧饱和度(S(v)O2).记录诱导期间低血压及气管插管心血管反应的发生情况.结果 3组间麻醉诱导期间低血压及气管插管心血管反应的发生率差异无统计学意义(P>0.05).与T0比较,各组T1,2时HR和MAP均降低,Ⅱ组T3时HR和MAP升高,Ⅲ组T4时MAP降低,Ⅰ组和Ⅱ组T2-4时S(v)O2升高(P<0.05);3组间各时点CVP、PCWP、CI、LVSWI和S(v)O2差异无统计学意义(P>0.05).结论 复合TCI异丙酚(血浆靶浓度2.0 μg/ml)时,静脉注射瑞芬太尼1 μg/kg负荷剂量后,持续静脉输注0.5 μg·kg-1·min-1麻醉诱导时血压和HR下降适度,可较好地抑制心脏瓣膜置换术病人气管插管时血液动力学反应. 相似文献
72.
本文定义了一类“近乎双线性”系统。可用以近似一类奇异摄动双线性系统,而且可以描述某些实际工业对象。并发现其控制器的设计较方便。文中还给出了一种简单的反馈控制器的设计方法。又对一类多输入双线性系统,提出一种设计反馈控制器的改进方案,根据Lyapunov定理得到一非线性反馈控制律。以上设计方法分别对某合成氨反应器作了应用研究,仿真结果表明了方法的有效性。 相似文献
73.
目的 探讨类比思维结合创设乐学情境教学在眼科护理实习教学中的应用研究。方法 选取2020年10月至2022年1月在空军军医大学第一附属医院西京医院眼科实习的90名护生作为研究对象。按照不同的教学方法分为对照组和观察组,对照组45名护生采用常规教学,观察组45名护生采用类比思维结合创设乐学情境教学。评估两组护生的综合考核成绩、教学效果调查问卷及学生对带教教师的总满意度。采用SPSS 22.0进行t检验和卡方检验。结果 观察组护生的理论知识考核成绩[(85.39±1.57) vs. (84.41±1.34)]、护理技能考核成绩[(87.52±0.04) vs. (82.64±0.05)均高于对照组;观察组护生的眼科护理工作中的用药安全意识、专业兴趣与自主学习性提升、协作组织能力增强、独立思考和自主学习能力提升、达到多学科知识融会贯通的目的、信息量与知识面改善、临床思维沟通交流能力增强、理论知识灵活应用、动手操作能力提高、培养创新意识各个方面评分均优于对照组;带教教师对学生学习态度、语言表达、呼唤沟通能力、独立解决问题能力等方面的评价,观察组高于对照组(P <0.05)。结论 类比思维结合创设乐学情境教学能提高护生的平均考核成绩和护理技能考核成绩,能改善学生对带教教师的满意度。 相似文献
74.
目的 探讨提高神经内科临床医学实习生临床思维能力的方法。方法 选择2017年至2018年临床医学实习生为研究对象,2018年为试验组(98人),2017年为对照组(95人)。试验组实施临床思维能力培养,对照组采用传统常规的方法培养。实习结束前,采用自制的《临床医学实习生临床思维能力调查问卷》进行调查,评价教学效果。使用SPSS 14.0进行t检验和卡方检验。结果 试验组与对照组均存在临床思维的片面性、表像性、定势性、被动性、懒惰性、简化性、混乱性等问题,试验组存在的临床思维方面问题较对照组明显下降(P<0.001),其中试验组的临床思维的片面性、表像性、定势性、被动性、懒惰性方面与对照组比较差异有统计学意义(P<0.05)。除语言沟通与表达能力外,试验组的其他临床思维能力自评得分与对照组比较差异都有统计学意义(P<0.05)。试验组的出科考核成绩与对照组比较差异也有统计学意义(P<0.05)。结论 临床医学生在神经内科实习阶段实施临床思维训练,有利于培养学生的临床思维能力,提高人才培养质量。 相似文献
75.
76.
Cerebellar connections with the motor cortex and the arcuate premotor area: an analysis employing retrograde transneuronal transport of WGA-HRP 总被引:3,自引:0,他引:3
We have employed transneuronal transport to examine the anatomical relationships between the deep cerebellar nuclei and 2 cortical motor areas: the primary motor cortex and the arcuate premotor area (APA). In the same animals, we have also examined the patterns of labeling in the thalamus and the red nucleus to provide evidence for the potential routes of transneuronal transport to the cerebellum. When the appropriate technical procedures were employed, cortical injections of wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) resulted in transneuronal labeling within portions of the contralateral deep cerebellar nuclei. Injections into the primary motor cortex labeled neurons in the dentate and in the 2 subdivisions of the interpositus. Injections into the APA labeled neurons in the dentate and in only the posterior subdivision of the interpositus. In most instances, dentate neurons were more intensely labeled following the cortical injections than interpositus neurons. The transneuronal labeling observed in the dentate nucleus was topographically organized. The dentate region that was labeled following injections into the "arm area" of the APA was caudal and ventral to the dentate region that was labeled following injections into the "arm area" of the primary motor cortex. This observation provides evidence for two "arm areas" in the dentate: one anatomically related to the APA, and the other related to the primary motor cortex. More than one route of transport may be responsible for the labeling of cerebellar neurons. We propose that the labeling observed in the dentate nucleus reflects the pattern of connections in the cerebellothalamocortical pathways that link the dentate with the cerebral cortex. Thus, our observations support the concept proposed by Schell and Strick (J. Neurosci. 4:539-560, '84)--that the cortical targets of the dentate nucleus include both the primary motor cortex and the APA. 相似文献
77.
Jaana M Ward MM Paré G Wakefield DS 《International journal of medical informatics》2005,74(9):719-731
Despite the growing interest in adopting information technology (IT) in healthcare, the degree of technology sophistication varies among healthcare organizations. Changes in the health care sector and continuous pressure to improve the quality of care have driven the evolution of IT in hospitals. This paper provides an overview of clinical IT sophistication in a sample of U.S. hospitals, and compares clinical IT capacities in this sample with a sample of Canadian hospitals. The instrument used for the comparison measures three clinical dimensions of IT sophistication: functional sophistication, technological sophistication and integration level. Clinical areas that were considered include patient management, patient care activities and clinical support activities. The comparison between hospitals in Iowa and Canada shows differences in clinical IT sophistication between the two settings. Hospitals in Iowa appear to have more technologies but fewer computerized processes and integration of patient management activities. Technological sophistication however, was low in both samples. Our findings confirm the construct validity of the measurement instrument and show initial evidence of its generalizability. More initiatives using the instrument would lead to enhancement in IT assessment tools that can be used for evaluation of IT in relation to patient management and quality outcomes. 相似文献
78.
H. Heuer Jörg Sangals 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,119(2):224-236
In two experiments the involvement of relative and fixed coordinate systems in visuomotor transformations was examined. The
experimental task required the successive performance of two movements in each trial, which had to “correspond” to different
visual stimuli. One kind of visual display indicated target positions by way of different horizontal positions of a vertical
line on a monitor (position mode), while the other indicated movement amplitudes by way of different lengths of a horizontal
line (amplitude mode). Formal analysis of variances and covariances of successive individual movements led to the conclusion
that in the position mode visuomotor transformations were based on a mixture of relative and fixed coordinate systems, while
in the amplitude mode only a relative coordinate system was involved. Thus, visuomotor transformations can be characterized
as mixtures of different coordinate systems, and their respective weights in the mixtures are task-dependent.
Received: 18 March 1997 / Accepted: 25 September 1997 相似文献
79.
Bresciani JP Ernst MO Drewing K Bouyer G Maury V Kheddar A 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,162(2):172-180
We tested whether auditory sequences of beeps can modulate the tactile perception of sequences of taps (two to four taps per sequence) delivered to the index fingertip. In the first experiment, the auditory and tactile sequences were presented simultaneously. The number of beeps delivered in the auditory sequence were either the same as, less than, or more than the number of taps of the simultaneously presented tactile sequence. Though task-irrelevant (subjects were instructed to focus on the tactile stimuli), the auditory stimuli systematically modulated subjects tactile perception; in other words subjects responses depended significantly on the number of delivered beeps. Such modulation only occurred when the auditory and tactile stimuli were similar enough. In the second experiment, we tested whether the automatic auditory-tactile integration depends on simultaneity or whether a bias can be evoked when the auditory and tactile sequence are presented in temporal asynchrony. Audition significantly modulated tactile perception when the stimuli were presented simultaneously but this effect gradually disappeared when a temporal asynchrony was introduced between auditory and tactile stimuli. These results show that when provided with auditory and tactile sensory signals that are likely to be generated by the same stimulus, the central nervous system (CNS) tends to automatically integrate these signals. 相似文献
80.
Using motion analysis data for foot-floor contact detection 总被引:2,自引:0,他引:2
Karcnik T 《Medical & biological engineering & computing》2003,41(5):509-512
A simple, fast and straightforward method was developed for automatically deriving foot-floor contact information from tracking
motion analysis system markers attached to the shoes of the subjects. The method was based on an accurate calibration of the
motion analysis system prior to the experiments and a trivial offline threshold-based algorithm using dedicated foot-attached
marker positions and velocities as inputs. The main purpose of the method was to obtain the results almost instantaneously.
The accuracy was poorer when compared with the classic, man-assisted and time-consuming methods, but the average error was
less than 0.1s compared with the force plate or pressure insole/foot switch-based methods. The method eliminates the need
for foot switches when a motion analysis system is already being used. As encumbrance is reduced for the subjects, the method
is also applicable to pathological gait patterns. 相似文献