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达芬奇手术机器人系统在普通外科的应用 总被引:2,自引:1,他引:2
20世纪80年代腹腔镜的出现使微创技术的发展取得了长足的进步,在此基础上,手术机器人的研发和应用开启了微创外科新纪元。本文通过达芬奇手术机器人系统在普通外科各类手术中的具体运用,分析了手术机器人对比传统腔镜技术的技术优势,及当前临床应用的瓶颈,并对高新技术的发展进行了点滴思考。 相似文献
74.
Determination of a behavioral transfer function: White-noise analysis of session-to-session response-ratio dynamics on concurrent VI VI schedules 下载免费PDF全文
Six pigeons were exposed to concurrent variable-interval schedules in which the programmed reinforcer ratios changed from session to session according to a pseudorandom binary sequence. This procedure corresponded to the stochastic identification paradigm (“white-noise experiment”) of systems theory and enabled the relation between log response ratios in the current session and log reinforcer ratios in all previous sessions to be determined. Such dynamic relations are called linear transfer functions. Both nonparametric and parametric representations of these, in the form of “impulse-response functions,” were determined for each bird. The session-to-session response ratios resulting from the session-to-session pseudorandom binary variations in reinforcer ratios were well predicted by the impulse-response functions identified for each pigeon. The impulse-response functions were well fitted by a second-order dynamic model involving only two parameters: a time constant and a gain. The mean time constant was 0.67 sessions, implying that the effects of abrupt changes in log reinforcer ratios should be 96% complete within about five sessions. The mean gain was 0.53, which was surprisingly low inasmuch as it should equal the sensitivity to reinforcement ratio observed under steady-state conditions. The same six pigeons were subjected to a similar experiment 10 months following the first. Despite individual differences in impulse-response functions between birds within each experiment, the impulse-response functions determined from the two experiments were essentially the same. 相似文献
75.
语言伴随性手势是人类语言交流的一个普遍的特征, 它可以发挥信息交流的功能。依据产生目的以及适用范围的不同, 手势可以分成表象性手势和非表象性手势。多数研究者认为, 语言和手势动作是“近亲”, 具有“家族相似性”。来自语言发展、认知心理学和认知神经科学的证据均表明, 手势和语言共享同一个交流系统。当手势动作和发音单词意义相同时, 手势动作受到单词发音的干扰, 同时引发发音共振峰2 (F2)的放大。手势和言语之间遵循互相作用理论, 它们作用的基础是语义一致性, 镜像神经系统完成了两者语义一致性的传递。由于语言伴随性手势和语言之间的关系是语言和行为结合良好的特例, 因此, 对语言伴随性手势的研究将有助于对人类心智有一个更深层次的认识和理解。 相似文献
76.
In times of war, news media coverage of the plight of civilian casualties plays a critical role in shaping attitudes regarding war's human costs. We proposed that these attitudes may also be surreptitiously influenced by the commercial advertisements that often accompany this coverage. Specifically, we hypothesized that when newspaper articles pertaining to civilian victims of war are flanked by luxury ads, conservatives, relative to liberals, will subsequently exhibit less concern for these victims. This proposition was based on the notion that commercial ads, particularly those promoting luxury items, make salient the gap between the “haves” and the “have‐nots” and thereby, at least implicitly, threaten the legitimacy of the current socioeconomic system. Drawing upon system justification theory, we posited that this threat would lead individuals with stronger system‐justification tendencies (conservatives), relative to those more open to challenging the current system (liberals), to show greater tolerance for civilian war casualties in order to defend the system's integrity. Evidence consistent with this hypothesis was found in a quasi‐experimental study (n = 329). 相似文献
77.
本研究采用经典类比任务,考察了3~5岁幼儿在主题-规则冲突条件下类比推理发展的水平与特点.结果表明:(1)在无主题联想条件下,幼儿的单维类比推理在3~4岁迅速发展,4~5岁发展较为平缓,而双维类比推理在3~5岁仍处于较低水平.(2)在主题—规则冲突条件下,幼儿在单维类比推理中表现出一定的主题联想优势反应;幼儿在双维类比推理中表现出较强的主题联想优势反应,年龄特点为:3岁幼儿有较强的主题联想优势反应,4岁幼儿的主题联想优势反应明显下降,而5岁幼儿又表现出较强的主题联想优势反应. 相似文献
78.
Previous research has found a relationship between individual differences in children’s precision when nonverbally approximating quantities and their school mathematics performance. School mathematics performance emerges from both informal (e.g., counting) and formal (e.g., knowledge of mathematics facts) abilities. It remains unknown whether approximation precision relates to both of these types of mathematics abilities. In the current study, we assessed the precision of numerical approximation in 85 3- to 7-year-old children four times over a span of 2 years. In addition, at the final time point, we tested children’s informal and formal mathematics abilities using the Test of Early Mathematics Ability (TEMA-3). We found that children’s numerical approximation precision correlated with and predicted their informal, but not formal, mathematics abilities when controlling for age and IQ. These results add to our growing understanding of the relationship between an unlearned nonsymbolic system of quantity representation and the system of mathematics reasoning that children come to master through instruction. 相似文献
79.
Research has established relationships between the personality dimensions of neuroticism and BIS and broad negative emotional reactivity. However, few researchers have examined the relationships among neuroticism, BIS, and discrete negative emotional reactivities. The present study examined whether individuals scoring high on neuroticism and BIS were more reactive across four discrete negative mood inductions, relative to those scoring low on these traits. Participants (n = 166) completed personality questionnaires, measures of current mood, viewed a specific mood-inducing film clip (sadness, anger, fear or disgust) and then reported their moods a second time. Results revealed that neuroticism/BIS was associated with high reactivity to the fear and sadness inductions. Neuroticism/BIS did not predict anger or disgust reactivity, but neuroticism/BIS and extraversion/BAS interacted in predicting anger. Although further research is needed to extend generalizability, it appears that neuroticism and BIS predict negative emotional reactivity broadly, but not ubiquitously. 相似文献
80.
Embodied cognition model states that the “simulation process” is necessary to the recognition of emotional significance of face. The present research explored the contribution of frontal motor brain components (i.e. mainly premotor area) to embodied cognition by using rTMS stimulation, to produce a temporary disruption of this specific cortical site. Secondly, short and long stimulus duration conditions were included to verify the contribution of the “simulation process” in response to overt and covert emotional stimulus comprehension. Nineteen subjects were asked to detect emotion/no emotion (anger, fear, happiness, neutral) in these two experimental conditions, by using a backward masking procedure. Five-second rTMS (1 Hz) was delivered before the stimulus onset. False alarms (Fa) and RTs increased and Hits decreased when frontal premotor brain activity was disrupted, specifically in response to anger and fear, for both long and shortduration condition. Thus, the present results highlight the main role of the frontal motor system for emotion facial expression processing. 相似文献