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【目的】 在“中国科技期刊卓越行动计划”实施三周年之际,有必要对我国科技期刊2035年迈入“世界第一方阵”目标的具体任务进行重新审视和预判,以进一步明确发展方向,动态调整推进思路。【方法】 采用国内外科技期刊、科技论文、科技期刊评价成果的系统性发展数据对科技期刊“世界第一方阵” 国家(或地区)在高水平科技期刊数量与质量层面的入围标准进行界定,在深入总结现有基础和优势的同时,对我国科技期刊综合实力与“世界第一方阵”国家(或地区)的现实差距进行逐一梳理和剖析,并对实现目标的可行性和推进思路进行研判和设计。【结果】 必须继续加强高水平英文科技期刊创办和培育力度、持续加大优秀中文科技期刊的建设强度、快速推进国内外科技期刊论文等质同效评价制度的建设与引导,并积极探索建立科学家和科研机构办好一流科技期刊的责任制度和贡献激励机制、创新发展编辑人才队伍培养与激励管理思路、深入实践灵活多样的期刊出版市场资本运作模式、稳步推进期刊出版市场机制和管理制度改革,为我国科技期刊事业的高质量发展提速增效。【结论】 虽然当前阶段目标任务艰巨,但迈入“世界第一方阵”未来可期。 相似文献
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《Clinical neurophysiology》2021,132(10):2357-2364
ObjectivesTo investigate the subcortical somatosensory evoked potentials (SEPs) to electrical stimulation of either muscle or cutaneous afferents.MethodsSEPs were recorded in 6 patients suffering from Parkinson’s disease (PD) who underwent electrode implantation in the pedunculopontine (PPTg) nucleus area. We compared SEPs recorded from the scalp and from the intracranial electrode contacts to electrical stimuli applied to: 1) median nerve at the wrist, 2) abductor pollicis brevis motor point, and 3) distal phalanx of the thumb. Also the high-frequency oscillations (HFOs) were analysed.ResultsAfter median nerve and pure cutaneous (distant phalanx of the thumb) stimulation, a P1-N1 complex was recorded by the intracranial lead, while the scalp electrodes recorded the short-latency far-field responses (P14 and N18). On the contrary, motor point stimulation did not evoke any low-frequency component in the PPTg traces, nor the N18 potential on the scalp. HFOs were recorded to stimulation of all modalities by the PPTg electrode contacts.ConclusionsStimulus processing within the cuneate nucleus depends on modality, since only the cutaneous input activates the complex intranuclear network possibly generating the scalp N18 potential.SignificanceOur results shed light on the subcortical processing of the somatosensory input of different modalities. 相似文献
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《Clinical neurophysiology》2021,132(9):2003-2011
ObjectiveA large N20 and P25 of the median nerve somatosensory evoked potential (SEP) predicts short survival in amyotrophic lateral sclerosis (ALS). We investigated whether high frequency oscillations (HFOs) over N20 are enlarged and associated with survival in ALS.MethodsA total of 145 patients with ALS and 57 healthy subjects were studied. We recorded the median nerve SEP and measured the onset-to-peak amplitude of N20 (N20o-p), and peak-to-peak amplitude between N20 and P25 (N20p-P25p). We obtained early and late HFO potentials by filtering SEP between 500 and 1 kHz, and measured the peak-to-peak amplitude. We followed up patients until endpoints (death or tracheostomy) and analyzed the relationship between SEP or HFO amplitudes and survival using a Cox analysis.ResultsPatients showed larger N20o-p, N20p-P25p, and early and late HFO amplitudes than the control values. N20p-P25p was associated with survival periods (p = 0.0004), while early and late HFO amplitudes showed no significant association with survival (p = 0.4307, and p = 0.6858, respectively).ConclusionsThe HFO amplitude in ALS is increased, but does not predict survival.SignificanceThe enlarged HFOs in ALS might be a compensatory phenomenon to the hyperexcitability of the sensory cortex pyramidal neurons. 相似文献
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Guoliang Zhang & Tao Xiong 《Communications In Computational Physics》2022,32(1):126-155
We propose a high order finite difference linear scheme combined with a
high order bound preserving maximum-principle-preserving (MPP) flux limiter to
solve the incompressible flow system. For such problem with highly oscillatory structure but not strong shocks, our approach seems to be less dissipative and much less
costly than a WENO type scheme, and has high resolution due to a Hermite reconstruction. Spurious numerical oscillations can be controlled by the weak MPP flux
limiter. Numerical tests are performed for the Vlasov-Poisson system, the 2D guiding-center model and the incompressible Euler system. The comparison between the linear
and WENO type schemes, with and without the MPP flux limiter, will demonstrate the
good performance of our proposed approach. 相似文献
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Jakub Pazdrowski Aleksandra Daczak‐Pazdrowska Adriana Polaska Joanna Ka
mierska Wojciech Barczak Mateusz Szewczyk Pawe Golusiski Zygmunt Adamski Ryszard aba Wojciech Golusiski 《Skin research and technology》2019,25(6):857-861
Radiodermatitis is one of the commonest side effects of radiotherapy. They are usually assessed by semi‐quantitative clinical scores, which are not validated and may be subject to inter‐observer variability. A few previous studies suggested that high‐frequency ultrasonography (HF‐USG) is useful in the assessment of the acute phase of radiation dermatitis in breast cancer patients. (a) To monitor skin changes by HF‐USG during the course of radiotherapy due to head and neck cancers, and (b) to determine whether there is any connection between skin sonograms and the skin scoring criteria. This prospective, observational study includes patients diagnosed with head and neck cancers, treated with radiotherapy or concomitant chemoradiation. The final analysis includes six patients. In every patient, the HF‐USG as well as dermatological assessment (target lesion score—TLS and CACE v. 4.0) were performed 4×: before, in the middle, day after, and 3 months after radiotherapy. There were significant differences between non‐irradiated skin thickness and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P < .0001), as well as between irradiated, unchanged skin thickness (TLS grade 0) and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P = .0002). There was no significant difference between non‐irradiated and irradiated, unchanged skin thickness (TLS grade 0; P = .9318). In four patients, we demonstrated subepidermal low echogenic band (SLEB). HF‐USG can be useful tool to noninvasive and objective assessment of skin changes during radiotherapy. 相似文献
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目的探究组织气氛在护士吞咽障碍知识水平与护理行为之间的中介效应。方法2019年6-7月,便利抽样法选取15个省市33所医院及医疗机构神经科、康复科具有吞咽障碍护理经验的231名护士为研究对象采用脑卒中吞咽障碍知识水平问卷、脑卒中吞咽障碍护理行为问卷及团队创新气氛量表对其进行调查。结果护士吞咽障碍知识水平总分为(56.69±13.50)分、护理行为得分为(140.65土32.02)分、组织气氛得分为(157.63±26.56)分。组织气氛与吞咽障碍知识水平(r=0.49,P<0.01)、护理行为(r=0.50,P<0.01)均呈正相关。组织气氛在知识水平和护理行为之间起中介作用,中介效应占总效应的83.18%。结论组织气氛在护士吞咽障碍知识水平与护理行为之间起中介作用,临床管理者可在提升护士吞咽障碍知识水平的基础上,通过提高组织气氛水平推进其护理行为。 相似文献
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