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进口集装箱堆存决策的两阶段强化学习方法
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作者 宋丽英 邓琨琦 +2 位作者 宁武 宋海涛 李四维 《交通运输系统工程与信息》 北大核心 2026年第1期283-294,共12页
进口集装箱堆存问题因卸船顺序与提箱顺序的矛盾以及堆场资源约束而呈现高度复杂性。针对这一挑战,本文面向自动化垂直布局堆场,提出一种基于深度强化学习的两阶段堆存决策方法。该方法将堆存过程建模为马尔可夫决策过程,在框架上引入... 进口集装箱堆存问题因卸船顺序与提箱顺序的矛盾以及堆场资源约束而呈现高度复杂性。针对这一挑战,本文面向自动化垂直布局堆场,提出一种基于深度强化学习的两阶段堆存决策方法。该方法将堆存过程建模为马尔可夫决策过程,在框架上引入“堆区决策-堆位决策”的分阶段结构,有效降低状态与动作空间的维度,并结合差异化奖励函数,将均衡堆区利用率、翻箱次数和提箱移动距离作为优化目标。算法设计上,第1阶段采用深度Q网络(DQN)实现堆区选择,第2阶段引入对偶深度Q网络(Dueling DQN)提升复杂状态下的堆位选择效率。实验结果表明,该方法能够在全堆场范围内形成均衡的堆存策略:在不同堆场密度和集装箱批量场景下均表现出稳定适应性,平均翻箱率控制在15%~27%,平均移动贝位数最大值为3.84贝·箱^(-1),分别较实际数据降低约61.5%与38.7%。与单阶段DQN、两阶段近端策略优化(PPO)和启发式算法相比,本文方法在收敛效率、决策效果和鲁棒性方面均具有明显优势。本文不仅验证了分阶段建模与差异化奖励机制在复杂堆存问题中的有效性,还为大规模自动化堆场的调度与资源优化提供了具有推广性的解决方案。 展开更多
关键词 物流工程 堆存决策 强化学习 进口集装箱 两阶段方法
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基于改进YOLO的矿卡驾驶员疲劳检测算法 被引量:2
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作者 杜威 宁武 +1 位作者 孟丽囡 陈雨潼 《现代电子技术》 北大核心 2025年第7期126-131,共6页
针对现有疲劳驾驶检测报警不及时、检测精度不高以及需要人为监管的问题,提出一种改进YOLOv5s的疲劳驾驶目标检测算法。该算法使用轻量的EfficientNet骨干网络作为YOLOv5s的主干网络来进行特征提取,使模型参数大幅减少,降低模型的训练时... 针对现有疲劳驾驶检测报警不及时、检测精度不高以及需要人为监管的问题,提出一种改进YOLOv5s的疲劳驾驶目标检测算法。该算法使用轻量的EfficientNet骨干网络作为YOLOv5s的主干网络来进行特征提取,使模型参数大幅减少,降低模型的训练时间;同时选用SIoU作为模型的损失函数,优化模型损失计算方法,提升模型的检测精度。结果表明,优化后的YOLOv5s目标检测算法与原YOLOv5s相比,模型尺寸减少了2%,平均准确率提升了0.9%,能够有效提升矿用生产车疲劳驾驶目标的检测效果。 展开更多
关键词 矿用生产车 疲劳检测 YOLOv5s EfficientNet 损失函数 特征提取 迁移学习 模型优化
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Agmatine Prevents Adaptation of the Hippocampal Glutamate System in Chronic Morphine-Treated Rats 被引量:5
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作者 Xiao-Fei Wang Tai-Yun Zhao +2 位作者 Rui-Bin Su ning wu Jin Li 《Neuroscience Bulletin》 SCIE CAS CSCD 2016年第6期523-530,共8页
Abstract Chronic exposure to opioids induces adaptation of glutamate neurotransmission, which plays a crucial role in addiction. Our previous studies revealed that agmatine attenuates opioid addiction and prevents the... Abstract Chronic exposure to opioids induces adaptation of glutamate neurotransmission, which plays a crucial role in addiction. Our previous studies revealed that agmatine attenuates opioid addiction and prevents the adaptation of glutamate neurotransmission in the nucleus accumbens of chronic morphine-treated rats. The hippocampus is important for drug addiction; however, whether adaptation of glutamate neurotransmission is modulated by agmatine in the hippocampus remains unknown. Here, we found that continuous pretreatment of rats with ascending doses of morphine for 5 days resulted in an increase in the hip- pocampal extracellular glutamate level induced by nalox- one (2 mg/kg, i.p.) precipitation. Agmatine (20 mg/kg, s.c.) administered concurrently with morphine for 5 days attenuated the elevation of extracellular glutamate levels induced by naloxone precipitation. Furthermore, in the hippocampal synaptosome model, agmatine decreased the release and increased the uptake of glutamate in synapto- somes from chronic morphine-treated rats, which might contribute to the reduced elevation of glutamate levels induced by agrnatine. We also found that expression of the hippocampal NR2B subunit, rather than the NR1 subunit, of N-methyl-D-aspartate receptors (NMDARs) was down-regulated after chronic morphine treatment, and agmatine inhibited this reduction. Taken together, agmatine pre- vented the adaptation of the hippocampal glutamate system caused by chronic exposure to morphine, including mod- ulating extracellular glutamate concentration and NMDAR expression, which might be one of the mechanisms underlying the attenuation of opioid addiction by agmatine. 展开更多
关键词 AGMATINE Opioid addiction HippocampusExtracellular glutamate NMDA receptors
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中国肺癌低剂量螺旋CT筛查指南(2018年版) 被引量:236
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作者 周清华 范亚光 +14 位作者 王颖 乔友林 王贵齐 黄云超 王新允 吴宁 张国桢 郑向鹏 步宏 李印 韦森 陈良安 胡成平 石远凯 孙燕 《中国肺癌杂志》 CAS CSCD 北大核心 2018年第2期67-75,共9页
背景与目的肺癌是导致中国癌症死亡的首要原因。已有的研究证明低剂量螺旋CT在肺癌高危人群进行肺癌筛查能降低20%的肺癌死亡。本研究的目的是建立适合中国国情的肺癌筛查指南。方法由国家卫计委任命的中国肺癌早诊早治专家组专家及部... 背景与目的肺癌是导致中国癌症死亡的首要原因。已有的研究证明低剂量螺旋CT在肺癌高危人群进行肺癌筛查能降低20%的肺癌死亡。本研究的目的是建立适合中国国情的肺癌筛查指南。方法由国家卫计委任命的中国肺癌早诊早治专家组专家及部分非专家组专家,包括:4名胸外科专家、4名胸部影像学专家、2名肿瘤学专家、2名肺内科专家、2名病理学专家和2名流行病学专家,共同参与了本指南的制定工作。专家们在系统评价了美国NLST和中国农村肺癌LDCT筛查结果及经验,并达成共识的基础上,共同推荐了本肺癌筛查指南。结果本指南推荐的肺癌高危人群为:年龄50岁-74岁;吸烟20包/年,或者戒烟5年。参与肺癌LDCT筛查前,需要获得筛查者的知情同意。肺癌筛查需与健康教育结合,向患者宣传吸烟对健康的危害。因此,健康教育应该整合到肺癌筛查全过程,以便帮助患者戒烟。结论 LDCT筛查能降低肺癌死亡率,本指南推荐中国肺癌高危人群进行LDCT筛查。但是,未来需要进行更多的研究,包括LDCT联合生物标志物用于肺癌筛查的研究,以优化肺癌LDCT筛查方法及技术。 展开更多
关键词 肺肿瘤 指南 筛查 LDCT 高危人群
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超重和肥胖患者建立气腹新穿刺点的探讨 被引量:4
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作者 孟凡强 刘孝明 +8 位作者 刘海滨 宁武 张国超 李超丰 牛晋卫 唐弢 裴东坡 王文跃 杨志英 《中国医刊》 CAS 2019年第11期1206-1207,共2页
目的探讨超重和肥胖患者经左腹直肌外缘与肋弓交点(Meng’s点)穿刺建立气腹的安全性和可行性。方法回顾性分析2015年4月至2019年3月在北京中日友好医院普外科采用Meng’s点穿刺建立气腹的40例超重和肥胖患者的临床资料,通过CT影像测定... 目的探讨超重和肥胖患者经左腹直肌外缘与肋弓交点(Meng’s点)穿刺建立气腹的安全性和可行性。方法回顾性分析2015年4月至2019年3月在北京中日友好医院普外科采用Meng’s点穿刺建立气腹的40例超重和肥胖患者的临床资料,通过CT影像测定所有患者Meng’s点、Palmer’s点(左锁骨中线肋缘下3cm)和脐周(脐环上缘)的腹壁厚度,记录从开始腹腔给CO2到气腹压达到12mmHg的时间和进气量,观察术中腹壁及腹腔内脏器副损伤情况,记录穿刺成功情况。结果全组Meng’s点、Palmer’s点和脐周的腹壁垂直厚度分别为(3.73±1.26)cm、(3.97±1.36)cm和(4.19±1.73)cm,三者比较差异无显著性(F=0.97,P=0.38)。经Meng’s点建立气腹时气腹针成功穿刺时间为(11.08±1.35)s,从开始腹腔给气到气腹压达到12mmHg的时间为(65.00±8.70)s,进气量为(4.08±0.39)L。全组无明确术中副损伤,建立气腹均一次气腹针穿刺成功。结论对超重和肥胖患者经Meng’s点建立气腹方便快捷、安全可行。 展开更多
关键词 超重 肥胖 腹腔镜 气腹 穿刺点
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Injectable agents for the induction of Peyronie’s disease in model rats:a comparative study
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作者 Guang-Jun Du Si-Yan Xing +5 位作者 ning wu Tong Wang Yue-Hui Jiang Tao Song Bai-Bing Yang Yu-Tian Dai 《Asian Journal of Andrology》 2025年第1期96-100,共5页
Peyronie’s disease(PD)is a disorder characterized by fibrous plaque formation in the penile tissue that leads to curvature and complications in advanced stages.In this study,we aimed to compare four injectable induct... Peyronie’s disease(PD)is a disorder characterized by fibrous plaque formation in the penile tissue that leads to curvature and complications in advanced stages.In this study,we aimed to compare four injectable induction agents for the establishment of a robust rat model of PD:transforming growth factor-β1(TGF-β1),fibrin,sodium tetradecyl sulfate(STS)combined with TGF-β1,and polidocanol(POL)combined with TGF-β1.The results showed that injection of TGF-β1 or fibrin into the tunica albuginea induced pathological endpoints without causing penile curvature.The STS+TGF-β1 combination resulted in both histological and morphological alterations,but with a high incidence of localized necrosis that led to animal death.The POL+TGF-β1 combination produced pathological changes and curvature comparable to STS+TGF-β1 and led to fewer complications.In conclusion,fibrin,STS+TGF-β1,and POL+TGF-β1 all induced PD with a certain degree of penile curvature and histological fibrosis in rats.The POL+TGF-β1 combination offered comparatively greater safety and clinical relevance and may have the greatest potential for PD research using model rats. 展开更多
关键词 FIBRIN Peyronie’s disease POLIDOCANOL rat model sodium tetradecyl sulfate TGF-β1
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Stereotactic radiotherapy for brain metastases of non-small cell lung cancer:A comprehensive review
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作者 Aamir Khan Hong-Fu Zhao +2 位作者 Hao Meng ning wu Lin-Lin Liu 《World Journal of Radiology》 2025年第8期1-12,共12页
Lung cancer,particularly non-small cell lung cancer(NSCLC),remains a leading cause of cancer-related death globally,and a significant number of patients develop brain metastasis(BM)as the disease progresses.The presen... Lung cancer,particularly non-small cell lung cancer(NSCLC),remains a leading cause of cancer-related death globally,and a significant number of patients develop brain metastasis(BM)as the disease progresses.The presence of BM,which affects up to 60%of patients with NSCLC,is correlated with an unfavorable prognosis and markedly decreased quality of life.Standard treatment options for BMs,such as whole-brain radiation therapy and surgery,have displayed limited efficacy in controlling disease progression,and they can cause significant neurocognitive side effects.Stereotactic radiotherapy(SRT),including stereotactic radiosurgery,fractionated SRT,and stereotactic body radiotherapy,represents an advanced and precise approach for treating BM that minimizes damage to surrounding healthy tissues.This review highlights recent advances in the application of SRT for treating BM of NSCLC,focusing on its underlying biological principles and mechanisms of action as well as the quality standards necessary for effective SRT implementation.The ability of SRT to deliver substantial radiation doses in a precisely targeted manner has resulted in better local tumor management,fewer side effects,and increased patient survival rates.Future research is crucial to improve SRT procedures and successfully incorporate them into multimodal therapy plans for patients with NSCLC and BM. 展开更多
关键词 Lung carcinoma Non-small cell lung cancer Brain metastasis Stereotactic radiotherapy Blood–brain barrier Tumor microenvironment
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Mapping human footprint changes over Qingzang Plateau
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作者 Jia Zhou ning wu Tao Lu 《Geography and Sustainability》 2025年第3期98-108,共11页
Mapping human footprint(HF)is crucial for understanding the cumulative anthropogenic pressures on the envi-ronment.However,its effectiveness is often hampered by the absence of fine-scale,high-quality spatio-temporal ... Mapping human footprint(HF)is crucial for understanding the cumulative anthropogenic pressures on the envi-ronment.However,its effectiveness is often hampered by the absence of fine-scale,high-quality spatio-temporal datasets.Addressing this gap,we present the first annual HF maps for the Qingzang Plateau(QP)from 1990 to 2020,at a 100 m×100 m resolution,boasting an accuracy exceeding 80%.Our findings reveal that the QP’s human-induced modifications were relatively low,with a median HF of 3.39 in 2020,significantly lower than the global average of 7.56.The northeast and mid-south regions of the QP emerged as hotspots for anthropogenic impact.Notably,over two-thirds(68.2%)of the QP registered an HF score below 4,classifying them as largely intact.However,the QP’s average HF score has escalated more swiftly than the global mean(0.0348/yr vs.0.0186/yr),particularly in the last decade,indicating escalating human pressures.In terms of stability,montane grasslands and shrublands comprised 75.1%of moderately or highly altered biomes in 2020.In contrast,tropical and subtropical moist broadleaf forests witnessed the most substantial HF increases.Encouragingly,26.29%of the QP experienced HF reductions over the past thirty years,highlighting potential conservation opportunities. 展开更多
关键词 Human impact Spatio-temporal pattern Conservation planning Environmental sustainability Management effectiveness
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Response surface optimization of preparation parameters and evaluation of the antioxidant and antihypertensive activities of Spirulina protein hydrolysates
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作者 Qishan SUO Zhenzhen DENG +4 位作者 Yang YUE Jing WANG ning wu Lihua GENG Quanbin ZHANG 《Journal of Oceanology and Limnology》 2025年第1期196-209,共14页
Safety,high protein content,and the numerous health benefits make Spirulina an outstanding source of bioactive peptides.Peptides from Spirulina,which exhibit antioxidant,anti-inflammatory,and antihypertensive effects,... Safety,high protein content,and the numerous health benefits make Spirulina an outstanding source of bioactive peptides.Peptides from Spirulina,which exhibit antioxidant,anti-inflammatory,and antihypertensive effects,may assist in the management of cardiovascular diseases(CVDs).Here,we present the optimization of enzyme-digested hydrolysates derived from Spirulina sp.by using response surface methodology(RSM).We also evaluated the biological activity of Spirulina protein hydrolysates(SPHs)in contributing to the amelioration of hypertension and associated cardiovascular diseases.Our findings suggest that Spirulina protein extracts contain a complex proteinaceous composition with phycocyanin being the dominant protein,as evidenced by both SDS-PAGE and LC-MS/MS profiling.Alkaline protease,protease K,andα-chymotrypsin exhibited a substantial hydrolytic effect on Spirulina protein,taking into account their degree of hydrolysis(DH),peptide yield,and molecular weight distribution.Single-factor experiments identified pH,temperature,and enzyme/substrate ratio as the key factors influencing DH.Moreover,optimal hydrolysis conditions for the proteases were determined via RSM,leading to a considerable enhancement of the actual DH.Bioassays showed that SPHs have strong antioxidant activity against various free radicals,with a higher ability to scavenge hydroxyl radicals.Furthermore,SPHs inhibited macrophage nitric oxide secretion and significantly inhibited angiotensin I-converting enzyme in vitro at 400μg/mL.It is worth noting that SPHs prepared with protease K exhibited a potent anti-hypertensive effect in vivo.The findings indicate the potential usefulness of including dietary SPHs in preventing hypertension and associated CVDs.This research could be valuable in guiding the development of health-promoting foods within the Spirulina industry. 展开更多
关键词 antioxidant activity antihypertensive effect angiotensin converting enzyme inhibition response surface methodology SPIRULINA
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Graphene/F_(16)CuPc synaptic transistor for the emulation of multiplexed neurotransmission
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作者 Zhipeng Xu Yao Ni +3 位作者 Mingxin Sun Yiming Yuan ning wu Wentao Xu 《Journal of Semiconductors》 2025年第1期215-223,共9页
We demonstrate a bipolar graphene/F_(16)CuPc synaptic transistor(GFST)with matched p-type and n-type bipolar properties,which emulates multiplexed neurotransmission of the release of two excitatory neurotransmitters i... We demonstrate a bipolar graphene/F_(16)CuPc synaptic transistor(GFST)with matched p-type and n-type bipolar properties,which emulates multiplexed neurotransmission of the release of two excitatory neurotransmitters in graphene and F_(16)CuPc channels,separately.This process facilitates fast-switching plasticity by altering charge carriers in the separated channels.The complementary neural network for image recognition of Fashion-MNIST dataset was constructed using the matched relative amplitude and plasticity properties of the GFST dominated by holes or electrons to improve the weight regulation and recognition accuracy,achieving a pattern recognition accuracy of 83.23%.These results provide new insights to the construction of future neuromorphic systems. 展开更多
关键词 synaptic transistor dual excitatory channels fast-switching plasticity multiplexed neurotransmission
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Efficient thermal rectification in nitrogen-doped carbon nanotube heterostructures
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作者 Zhibo Xing Yingguang Liu +3 位作者 Haochen Liu Yahao Wang Cheng Zhang ning wu 《Chinese Physics B》 2025年第11期42-52,共11页
Carbon nanotubes(CNTs)are widely used in various fields owing to their unique properties.In this study,three different types of nitrogen-doped CNT heterojunctions were constructed:parallel-doped(PCNT),vertically doped... Carbon nanotubes(CNTs)are widely used in various fields owing to their unique properties.In this study,three different types of nitrogen-doped CNT heterojunctions were constructed:parallel-doped(PCNT),vertically doped(VCNT),and mesh-doped(MCNT).Non-equilibrium molecular dynamics(NEMD)simulations were conducted to investigate their heat flux and thermal rectification(TR)effects.The results show that heat flux preferentially flows from nitrogen-doped regions to undoped regions,exhibiting distinct thermal rectification behavior,with PCNT showing the most pronounced effect.Interestingly,the TR ratio of the zigzag PCNT is significantly higher than that of the armchair PCNT.Subsequently,we examined the effects of system length and diameter on the TR ratio of the PCNT and found that the TR ratio increases and then decreases with increasing model length.In addition,the effect of defect density on the heat flux of the PCNT is peculiar.The phonon density of states,phonon dispersion,participation ratio,and phonon spectral heat flux were analyzed to elucidate the thermal transport behavior of phonons in the nanotubes.This study provides insights into the development and design of nitrogen-doped CNT thermal rectifiers. 展开更多
关键词 carbon nanotube heterojunction nitrogen doping thermal rectification nonequilibrium molecular dynamics
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基于单片机的三相AC-DC变换系统 被引量:1
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作者 宁武 张勇 +1 位作者 孟丽囡 阎宏涛 《电子测试》 2022年第23期31-33,共3页
针对传统电源稳定性差、输出效率低,以TIM4C123G单片机为控制核心,结合双闭环PFC算法,制作了三相AC-DC变换系统。电压、电流检测模块将采集到的信息送入TIM4C123G单片机。TIM4C123G单片机控制三相六开关整流桥的通断,将28V三相电压由交... 针对传统电源稳定性差、输出效率低,以TIM4C123G单片机为控制核心,结合双闭环PFC算法,制作了三相AC-DC变换系统。电压、电流检测模块将采集到的信息送入TIM4C123G单片机。TIM4C123G单片机控制三相六开关整流桥的通断,将28V三相电压由交流转为直流,通过DC-DC升降压模块调整直流输出电压为36V。经测试,系统稳定性更强,输出效率更高,运行效果良好。 展开更多
关键词 TIM4C123G单片机 检测模块 双闭环 三相六开关整流桥
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细菌纤维素支架的复合改性及生物性能 被引量:4
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作者 王静 徐俊青 +1 位作者 吴宁 毛丽贺 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2018年第4期94-98,共5页
采用原花青素交联和仿生矿化技术,以生物相容性良好的细菌纤维素(BC)为原材料制备了BC/多肽(pol)和BC/多肽/羟基磷灰石(HAp)复合材料,并利用场发射扫描电镜、X射线衍射仪和红外光谱仪对制备材料进行分析表征,采用成骨细胞评估了几种支... 采用原花青素交联和仿生矿化技术,以生物相容性良好的细菌纤维素(BC)为原材料制备了BC/多肽(pol)和BC/多肽/羟基磷灰石(HAp)复合材料,并利用场发射扫描电镜、X射线衍射仪和红外光谱仪对制备材料进行分析表征,采用成骨细胞评估了几种支架材料的生物相容性。结果表明,交联和仿生矿化成功地将pol和HAp引入到BC的表面和内部,细胞实验表明,3种支架材料均具有一定的生物相容性,且复合改性提高了支架材料的生物活性,制备的材料具有优异的性能,是具有应用前景的组织工程支架材料。 展开更多
关键词 细菌纤维素 多肽 复合 羟基磷灰石 生物相容性
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甲状腺癌手术后不留置引流管的安全性和可行性分析 被引量:2
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作者 陈占旗 宁武 +2 位作者 唐弢 邓周录 花瞻 《现代肿瘤医学》 CAS 北大核心 2021年第19期3376-3379,共4页
目的:探讨甲状腺癌根治术后不留置引流管的安全性和可行性。方法:选择从2013年09月到2019年07月在我院行甲状腺癌根治术后未留置引流管的75例患者。根据手术时间分为三个阶段:第一阶段,包括15例行单侧腺叶切除术的患者;第二阶段,包括14... 目的:探讨甲状腺癌根治术后不留置引流管的安全性和可行性。方法:选择从2013年09月到2019年07月在我院行甲状腺癌根治术后未留置引流管的75例患者。根据手术时间分为三个阶段:第一阶段,包括15例行单侧腺叶切除术的患者;第二阶段,包括14例患者,其中9例行单侧腺叶切除术,3例行单侧腺叶切除+颈中央组淋巴结清扫术,2例行全甲状腺切除+颈中央组淋巴结清扫术;第三阶段,包括46例患者,其中44例行单侧腺叶或全甲状腺切除+单侧或双侧颈中央组淋巴结清扫术,2例行单侧腺叶切除术。收集患者的一般资料,并进行随访。结果:75例患者中有分化型甲状腺癌74例(乳头状癌72例,滤泡状癌2例),髓样癌1例。第一、二和三阶段手术平均时间分别为(116.67±28.07)分钟、(129.29±36.31)分钟和(153.91±35.84)分钟,术中平均出血量分别为(34.33±47.09)mL、(29.29±24.09)mL和(28.70±15.03)mL,术后平均住院时间分别为(1.80±0.77)天、(2.29±1.64)天和(2.30±1.41)天。仅有第一阶段和第三阶段在手术平均时间方面存在显著性差异,其余各组间无明显统计学差异。术后血肿形成、喉返神经损伤和甲状旁腺损伤分别发生1例(1.3%)、2例(2.7%)和30例(40.0%)。均无因术后并发症需再次手术的情况。术后随访12~76个月,其中对侧甲状腺新发肿瘤1例,淋巴结转移癌2例,死亡1例,死因为脑血管意外。结论:分化型甲状腺癌的患者行单侧腺叶切除或全甲状腺切除术加颈中央组淋巴结清扫术后不放置引流管是安全和有效的。 展开更多
关键词 甲状腺癌 根治术 引流 并发症 出血
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基于虚拟仪器的程控放大电路测控装置设计 被引量:3
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作者 张勇 宁武 +1 位作者 孟丽囡 甄禹彤 《电子器件》 CAS 北大核心 2023年第4期921-926,共6页
针对传统仪器设备在实验教学中所存在的缺陷和问题,结合虚拟仪器的应用特点和优势,在NI ELVISⅡ实验平台基础之上设计了一套虚拟仪器测控装置。该装置的正弦信号由LabVIEW产生,通过NI ELVISⅡ实验平台输入程控放大电路,该电路两级放大,S... 针对传统仪器设备在实验教学中所存在的缺陷和问题,结合虚拟仪器的应用特点和优势,在NI ELVISⅡ实验平台基础之上设计了一套虚拟仪器测控装置。该装置的正弦信号由LabVIEW产生,通过NI ELVISⅡ实验平台输入程控放大电路,该电路两级放大,STM32单片机调节增益,实验平台的开关量切换负载电阻,在LabVIEW中实现数据采集功能,自动测量电压、显示波形,单片机的TFT LCD液晶屏显示数据参数。实验结果表明,该装置能够准确生成设定幅值和相位的波形、改变负载电阻值、自动测量波形输出电压、频率及相位,充分利用虚拟仪器测控装置的优势,极大节省了仪器费用,提高了实验效率。 展开更多
关键词 虚拟仪器 NI ELVISⅡ实验平台 STM32单片机 程控放大电路 开关量
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现代家居智能锁防系统设计与实现 被引量:3
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作者 张勇 宁武 孟丽囡 《现代电子技术》 2022年第20期49-53,共5页
针对现有的家居安防系统中,智能化整体水平较低,导致在数据检测、信号处理及远程控制等方面经常出现错误的问题,文中提出一种家居智能锁防系统。该系统通过组建基于ZigBee协议的物联网,无线连接家庭的传感器和智能锁,其检测信息通过Zig... 针对现有的家居安防系统中,智能化整体水平较低,导致在数据检测、信号处理及远程控制等方面经常出现错误的问题,文中提出一种家居智能锁防系统。该系统通过组建基于ZigBee协议的物联网,无线连接家庭的传感器和智能锁,其检测信息通过ZigBee无线通信模块发送给以STC12为核心的控制主机。若有报警,控制主机将报警信息通过WiFi无线传输模块上传到云端服务器,并在设备返回报警信息时,云端服务器通过数据库调取技术将报警信息发送给用户的手机APP界面,手机APP通过云端服务器的数据接口可远程进行传感器布/撤防、智能开/关锁和报警信息处理等操作。实验结果表明,所提出的家居智能锁防系统能够提高电路的稳定性,并及时准确地处理数据信息,可实现多用户的手机远程智能操作、实时监测和统一管理。 展开更多
关键词 智能锁 安全防护 远程控制 信息上传 无线传输 信息处理 实时监测
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基于单片机的变论域模糊PI车载供电系统设计 被引量:2
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作者 张勇 宁武 +2 位作者 孟丽囡 庞恒立 甄禹彤 《电子器件》 CAS 北大核心 2023年第3期739-745,共7页
针对现有车载供电系统效率低和常规PI控制策略超调量大、响应时间长、抗干扰性能差等问题,提出了基于单片机的变论域模糊PI供电系统。该系统可以输入低压直流电,经DC-DC升压电路、DC-AC电路变换,输出交流电压为小型用电器供电,并采用变... 针对现有车载供电系统效率低和常规PI控制策略超调量大、响应时间长、抗干扰性能差等问题,提出了基于单片机的变论域模糊PI供电系统。该系统可以输入低压直流电,经DC-DC升压电路、DC-AC电路变换,输出交流电压为小型用电器供电,并采用变论域模糊控制策略,根据误差大小对PI参数进行实时在线调整,从而满足最优的性能要求。实验结果表明,该系统效率高、响应速度快、电流波动小、电压稳定性高,具有较强的鲁棒性,证实所提出的方法可行。 展开更多
关键词 效率 变论域 模糊控制策略 误差 在线调整 稳定性
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干燥综合征合并冷凝集素病1例 被引量:2
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作者 王丽芳 石连杰 +2 位作者 宁武 高乃姝 王宽婷 《北京大学学报(医学版)》 CAS CSCD 北大核心 2023年第6期1130-1134,共5页
干燥综合征是以外分泌腺受累、出现高度淋巴细胞浸润为特征的自身免疫病,临床表现为口干、眼干,还可累及关节、皮肤及肝、肾、肺等内脏器官。冷凝集素病是低温时冷凝集素引起阻塞微循环、溶血性贫血的自身免疫病。当患者血液在抗凝采血... 干燥综合征是以外分泌腺受累、出现高度淋巴细胞浸润为特征的自身免疫病,临床表现为口干、眼干,还可累及关节、皮肤及肝、肾、肺等内脏器官。冷凝集素病是低温时冷凝集素引起阻塞微循环、溶血性贫血的自身免疫病。当患者血液在抗凝采血管中出现凝固时,需警惕合并冷凝集素病,如不及时治疗,可能会出现严重的溶血性贫血,甚至危及生命。现将北京大学首钢医院2022年收治的1例患者报告如下。 展开更多
关键词 干燥综合征 冷凝集 感染 糖皮质激素
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Chinese expert consensus statement on clinical diagnosis and treatment of malignant tumor bone metastasis and bone related diseases 被引量:19
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作者 Shiying Yu Zefei Jiang +4 位作者 Li Zhang Xiaohui Niu Lvhua Wang ning wu Jianhui Ma 《The Chinese-German Journal of Clinical Oncology》 CAS 2010年第1期1-12,共12页
Clinical diagnosis and treatment of malignant tumor bone metastasesOverview Bone is the most common place of metastases in ad-vanced malignant diseases. Constant improvement in the treatment of malignant tumors has r... Clinical diagnosis and treatment of malignant tumor bone metastasesOverview Bone is the most common place of metastases in ad-vanced malignant diseases. Constant improvement in the treatment of malignant tumors has resulted in prolonged survival time, and so as an increased incidence of osseous metastases and skeletal complications. 展开更多
关键词 恶性肿瘤 临床诊断 治疗 相关疾病 专家 中国 疾病发生 生存时间
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Increased Levels of p53 and PARP-1 in EL-4 Cells Probably Related with the Immune Adaptive Response Induced by Low Dose Ionizing Radiation in vitro 被引量:6
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作者 GUANG-HUI CHENG ning wu +4 位作者 DE-Fu JIANG HONG-GUANG ZHAO QIAN ZHANG JIAN-FENG WANG SHou-LIANG GONG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2010年第6期487-495,共9页
Objective This paper is to explore the DNA repair mechanism of immune adaptive response (AR) induced by low dose radiation (LDR), the changes of mRNA levels and protein expressions of p53, ATM, DNA-PK catalytic su... Objective This paper is to explore the DNA repair mechanism of immune adaptive response (AR) induced by low dose radiation (LDR), the changes of mRNA levels and protein expressions of p53, ATM, DNA-PK catalytic subunit (DNA-PKcs) and PARP-1 genes in the LDR-induced AR in EL-4 cells. Methods The apoptosis and cell cycle progression of EL-4 cells were detected by flow cytometry in 12 h after the cells received the pre-exposure of 0.075 Gy X-rays (inductive dose, D 1) and the succeeding high dose irradiation (challenge dose, D2; 1.0, 1.5, and 2.0 Gy X-rays, respectively) with or without wortmannin (inhibitor of ATM and DNA-PK) and 3-aminobenzamid (inhibitor of PARP-1). And the protein expressions and mRNA levels related to these genes were detected with flow cytometry and reverse transcription-polymerase chain reaction in 12 h after irradiation with D2. Results The mRNA and protein expressions of p53 and PARP-1 in EL-4 cells in the D1 + D2 groups were much lower than those in the D2 groups, and those of PARP-1 in the 3-AB + D2 and the 3-AB + D1 + D2 groups were much lower than those in the D2 and the D1 + D2 groups. The percentage of apoptotic EL-4 cells in the 3-AB + D1 + D2 groups was much higher than that in the D1 + D2 groups, that in the G0/G1 and the G2 + M phases was much higher, and that in the S phase were much lower. Although the ATM and DNA-PKcs mRNA and protein expressions in wortmannin + D1 + D2 groups were much lower than those in the D1 + D2 groups, there were no significant changes in the apoptosis and cell cycle progression between the wortmannin + D1 + D2 and the D1 + D2 groups. Conclusion PARP-1 and p53 might play important roles in AR induced by LDR. 展开更多
关键词 Low dose radiation (LDR) Adaptive response (AR) DNA repair
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