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An investigation was made into the directional sensitivity of cells in the macaque anterior superior temporal polysensory region (STPa) to the motion of objects. The cells studied were sensitive to the presence of motion but showed little or no selectivity for the form of the stimulus. Directional tuning was not continuously distributed about all possible directions. The majority of cells were most responsive to motion in a direction within 15° of one of the three cartesian axes (up/down, left/right, towards/away). Tuning to direction varied in sharpness. For most (34/37) cells the angular change in direction required to reduce response to half maximal was between 45 and 70° (for 3/37 cells it was > 90°). The estimates of the directionality (median I d = 0.97) of STPa cells was similar to that reported for posterior motion processing areas (the middle temporal area, MT, and the medial superior temporal area, MST). The tuning for direction (sharpness, distribution and discrimination) of the motion-sensitive STPa cells were found to be similar to the tuning for perspective view of STPa cells selective for static form of the head and body. On average the STPa responses showed a 100- to 300-ms transient burst of activity followed by a tonic discharge maintained at approximately 20% of the peak firing rate for the duration of stimulation. The responses of motion-sensitive STPa cells occurred at an earlier latency (mean 91 ms) than responses of cells selective for static form (mean 119 ms), but the time course of responses of the two classes of cell were similar in many other respects. The early response latency and directional selectivity indicate that motion sensitivity in STPa cells derives from the dorsal visual pathway via MT/MST. The similarity of tuning for direction and perspective view within STPa may facilitate the integration of motion and form processing within this high-level brain area.  相似文献   
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罗猛  杨萍 《黑龙江医药》2003,16(3):212-213
通过实验的方法来研究结晶过程中各种参数对氨苄西林晶型的影响来考察混合时对氨苄西林溶液结晶过程的影响,选择最佳的结晶工艺条件,更好地指导生产实践过程。经过实验考察,获得最佳的结晶工艺,使产品的各项质量指标提高,认为是氨苄西林的最佳结晶工艺。  相似文献   
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调查了90具童尸用状腺的基本形态,可分四型。其中以甲状腺由两侧叶及峡部组成者为最多,占50.22%。测量了甲状腺各部的长、宽、厚。分年龄组进行了数据的统计学处理,并计算出儿童与成人甲状腺各部相应值的百分比。结果显示:小儿甲状腺侧叶的长度和宽度在幼儿期(1—3岁)就已发育近成人的一半。随着年龄的增长,甲状腺各部的均值逐渐增加。除各部的宽度以及锥体叶的长度外,各相邻两组间同项均数的比较,经双侧T检验发现差异具有高度显著性(P<0.01)。  相似文献   
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网络时代的高速发展和建构主义学习理论的兴起引发了以Webquest样式为主的网络教学改革。Webquest样式的网络教学实践离不开网络教学目标的精心分析,网站学习内容的合理设计以及网菇教学模块的科学编排。Webquest样式的采用是对网络环境下探究式学习的有益尝试;有利于提高医学生的综合素质;有利于师生关系的重塑。  相似文献   
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本文介绍健康调查简表(SF-36)的发展及引进中国后在临床的应用概况,重点介绍其在妇科以慢性盆腔疼痛为主要症状相关疾病,如盆腔炎、子宫内膜异位症等的应用概况。临床如能将SF-36与特定疾病量表结合,将为妇科慢性盆腔疼痛评估提供一个重要而有意义的工具。  相似文献   
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IntroductionThe Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) is frequently used in clinical practice to evaluate cognitive function. It is quick to administer (20-30 minutes) and is not influenced by a learning effect. The RBANS includes 4 parallel versions and has a high discriminative ability.Our study provides normative data from the RBANS-E (Spanish-language version of RBANS form A) for a Spanish population aged 20 to 89 years.MethodsThe study included 609 subjects aged 20 to 89 years. Participants were evaluated at baseline with a short interview, a cognitive screening test (Mini–Mental State Examination), and a functional scale (Rapid Disability Rating Scale). The RBANS-E was then administered to all 609 participants.ResultsOur results show the influence of education on all subtest scores. Sex was observed to have no impact on any subtest.ConclusionOur study provides highly useful normative data for the cognitive evaluation of young and adult populations.  相似文献   
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《Vaccine》2020,38(33):5109-5113
A National Immunization Technical Advisory Group (NITAG) is a multi-disciplinary body of national experts that provides evidence-based recommendations to policy-makers, assisting them in making sound immunization policy and programme decisions. The World Health Organization (WHO) Regional Office for Europe is working to strengthen the capacity of newly-established NITAGs and has targeted efforts on low- and middle-income countries. The Regional Office, in collaboration with WHO Headquarters and USA Centers for Disease Control and Prevention (CDC), developed a new training strategy and held training workshops to improve NITAGs’ functioning and ability to make evidence-based recommendations. Feedback from countries that participated in trainings indicated that the updated training materials and interactive approach with follow-up technical support enabled them to align their NITAG charters and processes with WHO recommendations. To ensure continued progress, global and regional partners such as WHO and CDC should continue providing technical support to recently established NITAGs.  相似文献   
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《Vaccine》2018,36(26):3861-3867
In order to gather a global picture of vaccine hesitancy and whether/how it is changing, an analysis was undertaken to review three years of data available as of June 2017 from the WHO/UNICEF Joint Report Form (JRF) to determine the reported rate of vaccine hesitancy across the globe, the cited reasons for hesitancy, if these varied by country income level and/or by WHO region and whether these reasons were based upon an assessment. The reported reasons were classified using the Strategic Advisory Group of Experts (SAGE) on Immunization matrix of hesitancy determinants (www.who.int/immunization/sage/meetings/2014/october/SAGE_working_group_revised_report_vaccine_hesitancy.pdf). Hesitancy was common, reported by >90% of countries. The list of cited reasons was long and covered 22 of 23 WHO determinants matrix categories. Even the most frequently cited category, risk- benefit (scientific evidence e.g. vaccine safety concerns), accounted for less than one quarter of all reasons cited. The reasons varied by country income level, by WHO region and over time and within a country. Thus based upon this JRF data, across the globe countries appear to understand the SAGE vaccine hesitancy definition and use it to report reasons for hesitancy. However, the rigour of the cited reasons could be improved as only just over 1/3 of countries reported that their reasons were assessment based, the rest were opinion based. With respect to any assessment in the previous five years, upper middle income countries were the least likely to have done an assessment. These analyses provided some of the evidence for the 2017 Assessment Report of the Global Vaccine Action Plan recommendation that each country develop a strategy to increase acceptance and demand for vaccination, which should include ongoing community engagement and trust-building, active hesitancy prevention, regular national assessment of vaccine concerns, and crisis response planning (www.who.int/immunization/sage/meetings/2017/october/1_GVAP_Assessment_report_web_version.pdf).  相似文献   
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