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目的 分析2011—2020年安徽省钉螺分布时空特征,为全省钉螺精准防控提供参考。方法 收集2011—2020年安徽省实有钉螺面积、新发钉螺面积和感染性钉螺面积等钉螺分布指标并进行描述性分析,对实有和新发钉螺面积进行空间自相关、热点分析、标准差椭圆分析及时空扫描等分析,探索安徽省钉螺聚集与扩散高风险区。结果 2011—2020年,安徽省实有钉螺面积逐渐降低。2020年全省实有钉螺面积26 238.85 hm2,主要分布在湖沼型血吸虫病流行区。各年份间新发钉螺面积波动较大,2016年最高(1 287.65 hm2);2020年在池州市贵池区新发现1.96 hm2感染性钉螺面积。空间自相关和热点分析显示,2011—2020年安徽省实有钉螺面积分布具有空间聚集性(Z = 3.00 ~ 3.43,P均 < 0.01),热点主要集中在湖沼型流行区并沿长江南岸分布;冷点主要集中在皖南山区。2011—2020年安徽省新发钉螺面积分布在整体上不存在空间聚集性(Z = -2.20 ~ 1.71,P均> 0.05),局部呈散点分布。标准差椭圆分析显示,2011—2020年安徽省实有钉螺面积分布相对稳定,与长江流向一致;新发钉螺面积分布重心逐渐从长江安徽段下游向上游移动。时空扫描分析显示,2011—2020年安徽省实有钉螺面积两个高值聚集区以从长江安徽段下游到中游的顺序出现;新发钉螺面积两个高值聚集区聚集时间和范围类似,均分布在山区。结论 2011—2020年安徽省钉螺分布呈空间聚集性,存在向长江南岸、上游聚集的趋势,但山区钉螺扩散问题亦不容忽视,需加强对山区和长江沿岸新发钉螺孳生地的监测力度。  相似文献   
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Identifying transmission of hot spots with temporal trends is important for reducing infectious disease propagation. Cluster analysis is a particularly useful tool to explore underlying stochastic processes between observations by grouping items into categories by their similarity. In a study of epidemic propagation, clustering geographic regions that have similar time series could help researchers track diffusion routes from a common source of an infectious disease. In this article, we propose a two-stage scan statistic to classify regions into various geographic clusters by their temporal heterogeneity. The proposed scan statistic is more flexible than traditional methods in that contiguous and nonproximate regions with similar temporal patterns can be identified simultaneously. A simulation study and data analysis for a dengue fever infection are also presented for illustration.  相似文献   
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Temporal artery biopsy is recommended for diagnosis of suspected giant cell arteritis, a systemic vasculitis of older adults. There is currently no formal consensus for histological interpretation of the biopsies. Typical histological findings include a transmural lymphocytic infiltrate with a population of macrophages resulting in destruction of the internal elastic lamina. However, it is a patchy process and multiple tissue levels must be examined. It is important to be aware of various subtle features that may lead to a diagnosis of arteritis, and immunohistochemistry can be helpful in some cases. Some biopsies show unusual features that could raise a differential diagnosis of alternative vasculitides. When there is no evidence of arteritis in a specimen, there are often non-specific features seen in the context of age-related changes. All of these histological patterns require close clinicopathological correlation to ensure correct interpretation.  相似文献   
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Perceiving faces and understanding emotions are key components of human social cognition. Prior research with adults and infants suggests that these social cognitive functions are supported by superior temporal cortex (STC) and medial prefrontal cortex (MPFC). We used functional near-infrared spectroscopy (fNIRS) to characterize functional responses in these cortical regions to faces in early childhood. Three-year-old children (n = 88, M(SD) = 3.15(.16) years) passively viewed faces that varied in emotional content and valence (happy, angry, fearful, neutral) and, for fearful and angry faces, intensity (100%, 40%), while undergoing fNIRS. Bilateral STC and MPFC showed greater oxygenated hemoglobin concentration values to all faces relative to objects. MPFC additionally responded preferentially to happy faces relative to neutral faces. We did not detect preferential responses to angry or fearful faces, or overall differences in response magnitude by emotional valence (100% happy vs. fearful and angry) or intensity (100% vs. 40% fearful and angry). In exploratory analyses, preferential responses to faces in MPFC were not robustly correlated with performance on tasks of early social cognition. These results link and extend adult and infant research on functional responses to faces in STC and MPFC and contribute to the characterization of the neural correlates of early social cognition.  相似文献   
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Prediction of periodic event timing is an important function for everyday activities, while the exact neural mechanism remains unclear. Previous studies in nonhuman primates have demonstrated that neurons in the cerebellar dentate nucleus and those in the caudate nucleus exhibit periodic firing modulation when the animals attempt to detect a single omission of isochronous repetitive audiovisual stimuli. To understand how these subcortical signals are sent and processed through the thalamocortical pathways, we examined single-neuron activities in the central thalamus of two macaque monkeys (one female and one male). We found that three types of neurons responded to each stimulus in the sequence in the absence of movements. Reactive-type neurons showed sensory adaptation and gradually waned the transient response to each stimulus. Predictive-type neurons steadily increased the magnitude of the suppressive response, similar to neurons previously reported in the cerebellum. Switch-type neurons initially showed a transient response, but after several cycles, the direction of firing modulation reversed and the activity decreased for each repetitive stimulus. The time course of Switch-type activity was well explained by the weighted sum of activities of the other types of neurons. Furthermore, for only Switch-type neurons the activity just before stimulus omission significantly correlated with behavioral latency, indicating that this type of neuron may carry a more advanced signal in the system detecting stimulus omission. These results suggest that the central thalamus may transmit integrated signals to the cerebral cortex for temporal information processing, which are necessary to accurately predict rhythmic event timing.SIGNIFICANCE STATEMENT Several cortical and subcortical regions are involved in temporal information processing, and the thalamus will play a role in functionally linking them. The present study aimed to clarify how the paralaminar part of the thalamus transmits and modifies signals for temporal prediction of rhythmic events. Three types of thalamic neurons exhibited periodic activity when monkeys attempted to detect a single omission of isochronous repetitive stimuli. The activity of one type of neuron correlated with the behavioral latency and appeared to be generated by integrating the signals carried by the other types of neurons. Our results revealed the neuronal signals in the thalamus for temporal prediction of sensory events, providing a clue to elucidate information processing in the thalamocortical pathways.  相似文献   
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《Clinical neurophysiology》2021,132(3):737-743
ObjectiveTo determine whether the ictal scalp EEG findings suggest purely hippocampal epileptogenicity in patients with mesial temporal lobe epilepsy (mTLE) associated with hippocampal sclerosis (HS).MethodsTwenty-three patients with mTLE with pathologically confirmed HS were divided into 12 with epileptogenicity only in the hippocampus (HS only group) and 11 with epileptogenicity in both the hippocampus and temporal neocortex or other locations (HS plus group), based on the combination of surgical procedures, postoperative outcome, and pathological findings. Sixteen underwent selective amygdalohippocampectomy (SelAH) and 7 received anterior temporal lobectomy. Ictal scalp EEG findings of 79 focal impaired awareness seizures were compared between the HS only and HS plus groups. We focused on the 1–4 Hz rhythmic delta activity at ictal onset followed by 5–9 Hz rhythmic theta/alpha activity 10–30 s after the onset in the temporal region.ResultsThe initial delta and delayed theta/alpha (ID-DT) pattern was observed in 8 of 12 patients in the HS only group, but in none of 11 patients in the HS plus group (p < 0.01).ConclusionsID-DT pattern on ictal EEG suggests purely hippocampal epileptogenicity in mTLE with HS.SignificancePatients with the ID-DT pattern are likely to become seizure-free after SelAH.  相似文献   
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目的 分析2015–2017年长江江苏段流域钉螺时空分布现状,为江苏省消除血吸虫病、制定精准防治策略和措施提供依据。方法 2015–2017年在长江江苏段流域南京、镇江市和扬州市江滩中选取75块进行抽样调查,对3年各项螺情指标进行统计分析,采用空间自相关分析、核密度分析和“热点分析”工具探索钉螺时空分布及变化趋势。结果 2015–2017年长江江苏段流域钉螺平均密度存在空间自相关。扬州市活螺数、活螺密度整体下降,但2016年稍有上升。核密度及热点分析均发现长江江苏段流域活螺分布热点区域为扬州市和镇江市交界江滩附近区域。结论 江苏省长江流域钉螺分布存在空间自相关且存在“热点区域”,江滩钉螺监测工作仍然不可忽视。  相似文献   
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