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Jan Clemens Florian Rau R. Matthias Hennig K. Jannis Hildebrandt 《The European journal of neuroscience》2015,42(7):2390-2406
Sensory systems process stimuli that greatly vary in intensity and complexity. To maintain efficient information transmission, neural systems need to adjust their properties to these different sensory contexts, yielding adaptive or stimulus‐dependent codes. Here, we demonstrated adaptive spectrotemporal tuning in a small neural network, i.e. the peripheral auditory system of the cricket. We found that tuning of cricket auditory neurons was sharper for complex multi‐band than for simple single‐band stimuli. Information theoretical considerations revealed that this sharpening improved information transmission by separating the neural representations of individual stimulus components. A network model inspired by the structure of the cricket auditory system suggested two putative mechanisms underlying this adaptive tuning: a saturating peripheral nonlinearity could change the spectral tuning, whereas broad feed‐forward inhibition was able to reproduce the observed adaptive sharpening of temporal tuning. Our study revealed a surprisingly dynamic code usually found in more complex nervous systems and suggested that stimulus‐dependent codes could be implemented using common neural computations. 相似文献
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Arthi Sridhar B. M. Sunil Kumar Aarathi Rau A. T. K. Rau 《Indian journal of hematology & blood transfusion》2017,33(2):222-227
Dengue Fever (DF) may evolve into two life threatening forms—Dengue Hemorrhagic Fever (DHF) and Dengue Shock Syndrome (DSS). DHF is associated with increased vascular permeability and plasma leakage causing thrombocytopenia and loss of clotting factors into the third space and may result in bleeding initially due to thrombocytopenia and later due to disseminated intravascular coagulation (DIC), often as a terminal event. Prompt recognition and treatment of minor bleeds in DF children with incipient DIC with component therapy may be associated with improved survival while failure to do so is usually catastrophic. A sensitive marker for early DIC is the presence of D-dimer (DD) in the blood. To determine the correlation between the severity of thrombocytopenia and early DIC in children with DHF. The impact of additional factors like age and shock will also be evaluated. Case control prospective study of 60 DHF sero -positive children (1–15 years) with thrombocytopenia. After clinical evaluation they were divided into two equal groups based on the degree of thrombocytopenia (more than/less than 30,000/mm3). PT/APTT and DD levels were estimated in all children of both groups and statistical correlation was done. There was no significant difference in the DD levels between the two groups. However, children in either group, presenting with clinical features of shock and thrombocytopenia had significantly higher DD levels. Empirical component therapy in children with DHF based purely on their low platelet counts may not be justified. However, in DHF children with thrombocytopenia and features of shock, aggressive component therapy may prevent subsequent bleeding and may be justified. 相似文献
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Chi-Lun Rau Pei-Fang Jennifer Tsai Sheau-Farn Max Liang Jhih-Cian Tan Hong-Cheng Syu Yue-Ling Jheng Ting-Syuan Ciou Fu-Shan Jaw 《Health care management science》2013,16(4):352-365
This study uses a simulation model as a tool for strategic capacity planning for an outpatient physical therapy clinic in Taipei, Taiwan. The clinic provides a wide range of physical treatments, with 6 full-time therapists in each session. We constructed a discrete-event simulation model to study the dynamics of patient mixes with realistic treatment plans, and to estimate the practical capacity of the physical therapy room. The changes in time-related and space-related performance measurements were used to evaluate the impact of various strategies on the capacity of the clinic. The simulation results confirmed that the clinic is extremely patient-oriented, with a bottleneck occurring at the traction units for Intermittent Pelvic Traction (IPT), with usage at 58.9 %. Sensitivity analysis showed that attending to more patients would significantly increase the number of patients staying for overtime sessions. We found that pooling the therapists produced beneficial results. The average waiting time per patient could be reduced by 45 % when we pooled 2 therapists. We found that treating up to 12 new patients per session had no significantly negative impact on returning patients. Moreover, we found that the average waiting time for new patients decreased if they were given priority over returning patients when called by the therapists. 相似文献
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Until recently, axillary node clearance had long been the standard of care in patients with axillary node-positive disease. One stop nucleic acid sampling (OSNA) has been used to guide intraoperative decision-making regarding suitability for axillary node clearance (ANC). The aim of this study is to evaluate the use of OSNA following neoadjuvant chemotherapy (NACT) and whether it can predict lymph node burden in ANC. A single center, prospective cohort study was performed on 297 patients having OSNA between 2016 and 2019. Patients were sub-classified according to node positivity at diagnosis and those treated with NACT and outcomes included copy number and lymph node harvest. Axillary complete pathological response was observed in 24/36 patients (67%) following NACT. 14/16 patients (87%) having axillary node clearance had axillary node disease limited to 4 nodes. OSNA copy numbers were significantly higher in patients showing disease progression following NACT. Overall, 73% of patients with lymph node positivity at diagnosis could be successfully treated with a combination of NACT and lymph node excision of four nodes. De-escalating axillary surgical treatment to resection of four nodes following NACT may be effective in balancing oncological resection and limiting treatment morbidity. ONSA can correctly identify patients experiencing disease progression who would benefit from traditional three-level ANC. 相似文献
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ECG‐gated pulmonary artery CTA for evaluation of right ventricular function in patients with acute pulmonary embolism 下载免费PDF全文
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