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Forging of silaoxycarbocyclics by interrupted Catellani reaction
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作者 Yu-Chen Fang Jia-He Chen +5 位作者 Mi-Zhuan Li Hui-Min Li Mei Bai Yong-Zheng Chen Zi-Wei Gao Wen-Yong Han 《Chinese Chemical Letters》 2025年第7期328-333,共6页
Catalytic syntheses of silaoxycarbocyclics from an interrupted Catellani reaction of 3-iodochromones with bridged olefins and octamethyl-1,4-dioxacyclohexasilane is described.This protocol involves the oxidative addit... Catalytic syntheses of silaoxycarbocyclics from an interrupted Catellani reaction of 3-iodochromones with bridged olefins and octamethyl-1,4-dioxacyclohexasilane is described.This protocol involves the oxidative addition of chromonyl-norbornyl-palladacycle generated through successive oxidative addition of Pd(0)to 3-iodochromones,migratory insertion of NBE and intramolecular ortho-C(sp^(2))-H activation to the tetrasilane,thus motivating a(4+6)annulation and ring expansion.The synthetic practicality of current strategy is further proved by the late-stage modification of pharmaceuticals and natural products,gram-scale experiments,as well as the transformations of functional groups of silaoxycarbocyclics. 展开更多
关键词 Ring expansion Chromonyl-norbornyl-palladacycle interrupted Catellani reaction Silaoxycarbocyclics
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Comparison between interrupted closure technique and traditional closure technique in endoscopic full-thickness resection for treating gastric subepithelial lesions
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作者 Meng Zhang Jiao Liu +9 位作者 Yun-Peng Dong Qian Zhao Mei-Ling Lin Teng-Jiao Gao Jia-Li Feng Yi-Fei Wang Yu-Fan Guo Zhen Wang Wen Jia Zhuo Yang 《World Journal of Gastrointestinal Surgery》 2025年第6期342-352,共11页
BACKGROUND Gastric subepithelial lesions(SELs)are elevated lesions originating from the muscularis mucosa,submucosa,or muscularis propria,and may also include extraluminal lesions.For small SELs(less than 5 cm),comple... BACKGROUND Gastric subepithelial lesions(SELs)are elevated lesions originating from the muscularis mucosa,submucosa,or muscularis propria,and may also include extraluminal lesions.For small SELs(less than 5 cm),complete endoscopic excision is the preferred treatment.Endoscopic full-thickness resection(EFTR)has proven to be an effective approach.AIM To evaluate the efficacy of the interrupted closure technique compared to the traditional closure technique in EFTR for gastric SELs.METHODS This single-center,prospective,randomized controlled trial was conducted at a tertiary hospital from September 2023 to September 2024.A total of 90 patients who underwent EFTR for gastric SELs were randomly allocated to either the interrupted closure group(n=44)or the traditional closure group(n=46).RESULTS All patients had complete resection and wound closure without any severe postoperative complications.The incidence of intraoperative gas-related complications was significantly lower in the interrupted closure group than in the traditional closure group(2.27%vs 26.09%,P=0.001),demonstrating interrupted closure technique can reduce the incidence of gas-related issues.Statistical analysis revealed that the incidence of postoperative infection was significantly lower in the experimental group than in the control group(15.91%vs 41.30%,P=0.008).Additionally,the median duration of antibiotic use was lower in the experimental group(3.5 days vs 5 days,P=0.013).Abdominal pain levels on postoperative days 1 and 4 were also lower in the experimental group compared to the control group(P<0.001).CONCLUSION The interrupted closure technique in EFTR for treating gastric SELs is safe and effective,reducing the incidence of intraoperative gas complications and postoperative infections. 展开更多
关键词 Endoscopic full-thickness resection interrupted closure Gastric subepithelial lesion Gas complication Postoperative infection
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A method to address the challenges of charging conditions on incremental capacity analysis:An ICA-compensation technique incorporating current interrupt methods
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作者 Jinghua Sun Josef Kainz 《Journal of Energy Chemistry》 2025年第9期65-80,I0004,共17页
The incremental capacity analysis(ICA)technique is notably limited by its sensitivity to variations in charging conditions,which constrains its practical applicability in real-world scenarios.This paper introduces an ... The incremental capacity analysis(ICA)technique is notably limited by its sensitivity to variations in charging conditions,which constrains its practical applicability in real-world scenarios.This paper introduces an ICA-compensation technique to address this limitation and propose a generalized framework for assessing the state of health(SOH)of batteries based on ICA that is applicable under differing charging conditions.This novel approach calculates the voltage profile under quasi-static conditions by subtracting the voltage increase attributable to the additional polarization effects at high currents from the measured voltage profile.This approach's efficacy is contingent upon precisely acquiring the equivalent impedance.To obtain the equivalent impedance throughout the batteries'lifespan while minimizing testing costs,this study employs a current interrupt technique in conjunction with a long short-term memory(LSTM)network to develop a predictive model for equivalent impedance.Following the derivation of ICA curves using voltage profiles under quasi-static conditions,the research explores two scenarios for SOH estimation:one utilizing only incremental capacity(IC)features and the other incorporating both IC features and IC sampling.A genetic algorithm-optimized backpropagation neural network(GABPNN)is employed for the SOH estimation.The proposed generalized framework is validated using independent training and test datasets.Variable test conditions are applied for the test set to rigorously evaluate the methodology under challenging conditions.These evaluation results demonstrate that the proposed framework achieves an estimation accuracy of 1.04%for RMSE and 0.90%for MAPE across a spectrum of charging rates ranging from 0.1 C to 1 C and starting SOCs between 0%and 70%,which constitutes a major advancement compared to established ICA methods.It also significantly enhances the applicability of conventional ICA techniques in varying charging conditions and negates the necessity for separate testing protocols for each charging scenario. 展开更多
关键词 Lithium-ion batteries Incremental capacity analysis Charging conditions State of health Current interrupt method
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Research Progress on Nursing Interruptions in the Operating Room
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作者 Yajing Ling Mingming Wang +3 位作者 Renmin Zhang Shuting Tang Yan Chen Peng Wang 《Journal of Clinical and Nursing Research》 2025年第9期295-303,共9页
In recent years,research on nursing interruptions has been conducted at various levels in emergency departments,intensive care units,hemodialysis centers,operating rooms,and sterilization and supply centers.Nursing in... In recent years,research on nursing interruptions has been conducted at various levels in emergency departments,intensive care units,hemodialysis centers,operating rooms,and sterilization and supply centers.Nursing interruptions are closely related to adverse nursing events,and interruptions in operating room nursing can significantly impact the success of a patient’s surgery.However,there is a lack of in-depth theoretical research on safety risk assessment and response decision-making by operating room nurses when faced with nursing interruptions.This article reviews the concept,current status,and impact of nursing interruptions in the operating room,analyzes the cognitive level,coping strategies,and negative emotions of operating room nurses,and elaborates on management strategies to provide references for research and management of nursing interruptions in the operating room. 展开更多
关键词 Operating room nursing Nursing interruptions Safety management
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Nonperiodic interrupted sampling repeater jamming suppression for inverse synthetic aperture radar
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作者 WU Qihua ZHAO Feng +3 位作者 ZHAO Tiehua LIU Xiaobin XU Zhiming XIAO Shunping 《Journal of Systems Engineering and Electronics》 2025年第4期940-950,共11页
Nonperiodic interrupted sampling repeater jamming(ISRJ)against inverse synthetic aperture radar(ISAR)can obtain two-dimensional blanket jamming performance by joint fast and slow time domain interrupted modulation,whi... Nonperiodic interrupted sampling repeater jamming(ISRJ)against inverse synthetic aperture radar(ISAR)can obtain two-dimensional blanket jamming performance by joint fast and slow time domain interrupted modulation,which is obviously dif-ferent from the conventional multi-false-target deception jam-ming.In this paper,a suppression method against this kind of novel jamming is proposed based on inter-pulse energy function and compressed sensing theory.By utilizing the discontinuous property of the jamming in slow time domain,the unjammed pulse is separated using the intra-pulse energy function diffe-rence.Based on this,the two-dimensional orthogonal matching pursuit(2D-OMP)algorithm is proposed.Further,it is proposed to reconstruct the ISAR image with the obtained unjammed pulse sequence.The validity of the proposed method is demon-strated via the Yake-42 plane data simulations. 展开更多
关键词 jamming suppression compressed sensing(CS) interrupted sampling repeater jamming(ISRJ) energy function inverse synthetic aperture radar(ISAR).
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Evaluating the impact of refined drug control on orthopedic medication use in the DRGs system:An interrupted time series analysis
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作者 Tiantian Xu Yingqiu Tu +3 位作者 Shengtao Zhang Jun Xiao Bin Zhang Fuchong Lai 《Journal of Chinese Pharmaceutical Sciences》 2025年第8期775-783,共9页
In the context of the Diagnosis Related Groups(DRGs)system,the orthopedic hospital implemented refined drug control to provide a pharmacological reference for promoting rational clinical drug use.A statistical analysi... In the context of the Diagnosis Related Groups(DRGs)system,the orthopedic hospital implemented refined drug control to provide a pharmacological reference for promoting rational clinical drug use.A statistical analysis was conducted on the hospital’s data from January to December 2021(prior to the implementation of control),focusing on the types of unreasonable prescriptions.A multi-dimensional analysis was also conducted to identify the underlying causes of inappropriate medication practices.Following this,refined drug control measures were introduced,and data from January to December 2022(post-control)were compared,examining factors such as the average drug cost,drug expenses for the IC29 diagnosis group,and the drug cost ratio.An interrupted time-series analysis was employed to evaluate the effects of these interventions.The results showed that after the implementation of refined drug control in the orthopedic department,significant reductions were observed in the average cost per patient,average drug cost per patient,drug cost ratio,cost consumption index,average length of hospital stay,and allocation ratio(P<0.05).In particular,the first month of control(January 2022)saw a marked decrease in average drug costs per patient by 1272.90 yuan(P<0.01),a reduction in the drug cost ratio by 0.98%,and a decline in drug costs for the IC29 diagnosis group by 616.79 yuan(P>0.05).Moreover,the rate of unreasonable inappropriate prescribing dropped dramatically from 40.48%in 2021 to 3.57%by December 2022.The refined control of drug use within the orthopedic hospital significantly improved the rationality of clinical prescribing practices,reduced the occurrence of adverse drug reactions,and enhanced patient adherence to prescribed treatments.These findings demonstrated considerable clinical value in promoting efficient and safe drug use. 展开更多
关键词 Refined control of drugs Average drug cost interrupted time series
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Effect of interrupted aging on mechanical properties and corrosion resistance of 7A75 aluminum alloy 被引量:4
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作者 Xian-wen YANG Ling-ying YE +1 位作者 Yong ZHANG Quan-shi CHENG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第8期2415-2430,共16页
The effects of interrupted aging on mechanical properties and corrosion resistance of 7A75 aluminum alloy extruded bar were investigated through various analyses,including electrical conductivity,mechanical properties... The effects of interrupted aging on mechanical properties and corrosion resistance of 7A75 aluminum alloy extruded bar were investigated through various analyses,including electrical conductivity,mechanical properties,local corrosion properties,and slow strain rate tensile stress corrosion tests.Microstructure characterization techniques such as metallographic microscopy,scanning electron microscopy(SEM),and transmission electron microscopy(TEM)were also employed.The results indicate that the tensile strength of the alloy produced by T6I6 aging is similar to that produced by T6I4 aging,and it even exceeds 700 MPa.Furthermore,the yield strength increases by 52.7 MPa,reaching 654.8 MPa after T6I6 aging treatment.The maximum depths of intergranular corrosion(IGC)and exfoliation corrosion(EXCO)decrease from 116.3 and 468.5μm to 89.5 and 324.3μm,respectively.The stress corrosion factor also decreases from 2.1%to 1.6%.These findings suggest that the alloy treated with T6I6 aging exhibits both high strength and excellent stress corrosion cracking resistance.Similarly,when the alloy is treated with T6I4,T6I6 and T6I7 aging,the sizes of grain boundary precipitates(GBPs)are found to be 5.2,18.4,and 32.8 nm,respectively.The sizes of matrix precipitates are 4.8,5.7 and 15.7 nm,respectively.The atomic fractions of Zn in GBPs are 9.92 at.%,8.23 at.%and 6.87 at.%,respectively,while the atomic fractions of Mg are 12.66 at.%,8.43 at.%and 7.00 at.%,respectively.Additionally,the atomic fractions of Cu are 1.83 at.%,2.47 at.%and 3.41 at.%,respectively. 展开更多
关键词 7A75 aluminum alloy interrupted aging aging precipitation behavior mechanical properties intergranular corrosion exfoliation corrosion stress corrosion cracking
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Hybrid Procedure for Interruption of Aortic Arch Associated with Bicuspid Aortic Valve Stenosis in an Infant
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作者 Jiajun Xu Zhuo Shi +1 位作者 Shanshan Shi Xiangming Fan 《Congenital Heart Disease》 SCIE 2024年第5期535-540,共6页
Interrupted Aortic Arch(IAA)combined with aortic stenosis(AS)is a rare and complex congenital cardiac anomaly that presents significant challenges in clinical management.In this letter,we aim to share our experience i... Interrupted Aortic Arch(IAA)combined with aortic stenosis(AS)is a rare and complex congenital cardiac anomaly that presents significant challenges in clinical management.In this letter,we aim to share our experience in performing hybrid procedures on an infant diagnosed with IAA combined with bicuspid AS.This child exhibited significant recovery during follow-up. 展开更多
关键词 NEONATE interruption of aortic arch aortic stenosis hybrid procedurecript
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Pulsatile gonadotropin-releasing hormone therapy induces spermatogenesis in pituitary stalk interruption syndrome:A case report and review of the literature
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作者 Jin-Long Xie Hai-Ying Zhu +5 位作者 Yang Dong Ping-Ping Sun Dan-Dan Qi Su-Xian Luan Yan Zhang Hua-Gang Ma 《World Journal of Clinical Cases》 SCIE 2024年第20期4348-4356,共9页
BACKGROUND Pituitary stalk interruption syndrome(PSIS)is a rare anatomical defect of the pituitary gland falling under the spectrum of holoprosencephaly phenotypes.It is characterized by a deficiency in anterior pitui... BACKGROUND Pituitary stalk interruption syndrome(PSIS)is a rare anatomical defect of the pituitary gland falling under the spectrum of holoprosencephaly phenotypes.It is characterized by a deficiency in anterior pituitary hormones,such as growth hormone,gonadotropins,and thyroid hormones.Due to the syndrome's rarity and nonspecific manifestations,there is a lack of standardized treatment strategies.Consequently,early diagnosis through imaging and on-time intervention are crucial for improving patients’outcomes.CASE SUMMARY A 30-year-old man presented with absent secondary sexual characteristics and azoospermia.Laboratory evaluation revealed a deficiency in gonadotropins,while thyroid function was mostly within normal ranges.Magnetic resonance imaging of the pituitary gland showed pituitary stalk agenesis,hypoplasia of the anterior pituitary,and ectopic posterior pituitary,leading to the diagnosis of PSIS.Initially,the patient underwent 6 mo of gonadotropin therapy without significant changes in hormone levels and secondary sexual characteristics.Pulsatile gonadotropin-releasing hormone therapy was then administered,resulting in the detection of sperm in the semen analysis within 3 mo.After 6 mo,routine semen tests showed normal semen quality.The couple faced challenges in conceiving due to abstinence and underwent three cycles of artificial insemination,which was unsuccessful.They also attempted in vitro fertilization,but unfortunately,the woman experienced a miscarriage 10 wk after the embryo transfer.CONCLUSION Early detection,accurate diagnosis,and timely treatment are crucial in improving the quality of life and fertility of PSIS patients. 展开更多
关键词 Pituitary stalk interruption syndrome Hypogonadotropic hypogonadism SPERMATOGENESIS Pulsatile gonadotropinreleasing hormone therapy Case report
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Pituitary stalk interruption syndrome complicated with liver cirrhosis:A case report
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作者 Min Chang Shi-Yu Wang +5 位作者 Zi-Yu Zhang Hong-Xiao Hao Xin-Gang Li Jing-Jing Li Yao Xie Ming-Hui Li 《World Journal of Hepatology》 2024年第11期1348-1355,共8页
BACKGROUND Pituitary stalk interruption syndrome(PSIS)is a rare disorder,often characterized by delayed growth and development,short stature,and hypogonadism as the main clinical manifestations.It is not clear whether... BACKGROUND Pituitary stalk interruption syndrome(PSIS)is a rare disorder,often characterized by delayed growth and development,short stature,and hypogonadism as the main clinical manifestations.It is not clear whether PSIS can lead to liver cirrhosis.CASE SUMMARY This paper reported a case of liver cirrhosis of unknown origin.The patient was admitted to Beijing Ditan Hospital Affiliated to Capital Medical University in November 2023.The diagnosis of PSIS complicated with liver cirrhosis was established after a series of blood tests and pituitary magnetic resonance imaging examination.CONCLUSION We also reviewed the literature from both domestic and international sources to deepen the clinical understanding of PSIS in conjunction with liver cirrhosis among medical practitioners. 展开更多
关键词 Pituitary stalk interruption syndrome Growth hormone Magnetic resonance imaging Liver cirrhosis
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Influence of Interrupted Childhood Biographies on Health Development: Evaluation of the Scientific Literature on the Example of Being Taken into Care*
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作者 Manuela Loderer Ursula Gresser 《Journal of Biosciences and Medicines》 2024年第7期108-119,共12页
Background: An interrupted family history, as is the case after taking someone into care, can complicate collecting family anamnesis data. In addition, the interrupted family history itself could be considered part of... Background: An interrupted family history, as is the case after taking someone into care, can complicate collecting family anamnesis data. In addition, the interrupted family history itself could be considered part of a person’s risk profile. Aim and methods: Literature analysis was conducted to examine whether there are scientific studies on health development after placement in out-of-home-care in order to recognise any existing medical characteristics that may be relevant for internal medical care. Results: There are few scientific publications on the health development of people after being placed in out-of-home-care. Direct reactions to the stress of being taken into custody include nausea and fever. However, effects that go beyond the acute situation and last into adulthood have also been described, such as AD(H)D, asthma, diabetes, cancer, hypertension and cardiovascular diseases (myocardial infarction, stroke), epilepsy and increased overall mortality in adulthood. Studies show that not only previous experience but also the stress of being taken into care is triggers for this. Conclusion: Information about a previous institutionalisation can hence be important for internal medical practice. The available scientific literature shows heterogeneous study methodology and no group of people with experience of out-of-home-placement has yet been scientifically accompanied for a long time period. Further studies on this could help to better weigh up the consequences of omitting and conducting an intervention for child/youth protection as well as to improve the medical care for this group of people. 展开更多
关键词 Taking into Care Out-of-Home-Care interrupted Family History Physical Outcomes Internal Medicine
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基于双断点中断时间序列分析的甘肃省PCI手术冠心病患者住院费用变化趋势研究 被引量:1
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作者 韩雪梅 康盼 +9 位作者 崔秀芸 陶生鑫 司苗苗 易济琨 马亦晨 马子媛 李婧宜 王星星 苗瑞 张嘉文 《中国循证医学杂志》 北大核心 2025年第3期265-272,共8页
目的分析集采政策实施前、药品集采政策实施后和耗材集采政策实施后患者住院费用的变化,探索集采政策实施成效。方法本研究为回顾性研究,数据来源于甘肃省卫生健康委员会卫生信息统计中心的病案首页数据,共纳入甘肃省2018年1月1日至2022... 目的分析集采政策实施前、药品集采政策实施后和耗材集采政策实施后患者住院费用的变化,探索集采政策实施成效。方法本研究为回顾性研究,数据来源于甘肃省卫生健康委员会卫生信息统计中心的病案首页数据,共纳入甘肃省2018年1月1日至2022年12月31日期间PCI手术冠心病住院患者32938例。采用双断点中断时间序列模型分析集采政策实施不同阶段患者住院费用变化趋势。结果在集采政策实施的三个阶段次均住院总费用分别为46149.49元、46629.12元、28771.76元。药品集中带量采购政策实施时,次均住院总费用、药品费、耗材费、医疗服务费分别即刻下降4.64%、5.62%、18.12%、8.85%、25.28%。药品集中带量采购政策实施后,次均自付费用、治疗费、其他费用仍保持上升趋势,平均每月上升2.23%、1.51%、1.21%。耗材集采政策实施后,次均医疗服务费即刻上升23.75%,次均住院总费用、自付费用、耗材费、治疗费、康复费均呈下降趋势。结论药品集采政策和耗材集采政策的实施有效控制了PCI手术冠心病患者住院费用,患者个人经济负担减轻,但耗材费和次均医疗服务性费用变化幅度较小,未来还需要进一步优化耗材集采政策,完善医疗服务价格补偿机制,提升医疗服务价值。 展开更多
关键词 中断时间序列分析 集中带量采购 住院费用 冠心病 PCI手术
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基于间断时间序列法分析集采政策对注射用非甾体抗炎药使用的影响
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作者 汪江涛 蒋慧莲 +4 位作者 叶鸣 方佳 赵磊 朱和平 丁伯平 《中国新药与临床杂志》 北大核心 2025年第6期467-472,共6页
目的分析药品集中带量采购(以下简称“集采”)政策对医疗机构注射用非甾体抗炎药(NSAIDs)使用的影响。方法采用间断时间序列模型分析安徽省芜湖市中医医院2019年3月至2024年6月注射用NSAIDs月度采购量和采购金额的变化情况。结果集采政... 目的分析药品集中带量采购(以下简称“集采”)政策对医疗机构注射用非甾体抗炎药(NSAIDs)使用的影响。方法采用间断时间序列模型分析安徽省芜湖市中医医院2019年3月至2024年6月注射用NSAIDs月度采购量和采购金额的变化情况。结果集采政策实施后,中标和非中标NSAIDs均有不同程度的降价,且中标药品降价幅度较大。政策执行当月,氟比洛芬、帕瑞昔布和酮咯酸氨丁三醇的月采购金额均显著下降(β_(2)<0,P<0.05或P<0.01)。执行集采政策后,帕瑞昔布的月采购量呈上升趋势(β_(1)+β_(3)>0,P<0.01),氟比洛芬、帕瑞昔布和酮咯酸氨丁三醇的月采购金额均呈下降趋势(β_(1)+β_(3)<0)。结论集采后NSAIDs中标品种价格普遍降低,本院的用药结构发生变化,患者的用药负担减轻。采取多元化的采购方式,合理分配中标和非中标药品的采购份额,可以更好地满足临床和患者的差异化用药需求。 展开更多
关键词 药品集中带量采购 间断时间序列 非甾体抗炎药 氟比洛芬 帕瑞昔布 酮咯酸氨丁三醇
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基于中断时间序列回归评价抗菌药物治疗前病原学送检率干预措施的效果
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作者 王莹 金美娟 +3 位作者 丁蔚 赵瑶 宋晓超 韩如慧 《中华医院感染学杂志》 北大核心 2025年第21期3320-3325,共6页
目的评估实施提高抗菌药物治疗前病原学送检率系列干预措施后送检情况的变化,以优化抗菌药物应用管理。方法研究对象为苏州大学附属第一医院2021年7月-2024年6月医嘱目的为治疗使用抗菌药物的97146例住院患者,以2023年1月为干预节点,202... 目的评估实施提高抗菌药物治疗前病原学送检率系列干预措施后送检情况的变化,以优化抗菌药物应用管理。方法研究对象为苏州大学附属第一医院2021年7月-2024年6月医嘱目的为治疗使用抗菌药物的97146例住院患者,以2023年1月为干预节点,2021年7月-2022年12月设为干预前组,2023年1月-2024年6月设为干预后组,使用中断时间序列分析干预前后抗菌药物病原学送检率的变化趋势,利用卡方检验评估多重耐药菌检出率与医院感染率的变化。结果实施干预后,抗菌药物治疗前病原学送检率、联合使用重点药物前病原学送检率和医院感染诊断相关病原学送检率较干预前呈上升趋势(均P<0.05)。中断时间序列分析结果表明长期效益上看干预措施能提高限制级、特殊级及总体抗菌药物的治疗前病原学送检率,净效益分别为0.85%、0.67%和0.68%(均P<0.05),但联合使用重点药物病原学送检率无统计学差异。干预后多重耐药菌医院感染率由0.46%降低至0.27%(P<0.001);多重耐药菌检出率为25.73%,与干预前27.47%比较,无统计学差异。结论科学合理的干预能有效提升抗菌药物治疗前的病原学送检率,但是联合使用重点药物的病原学送检以及多重耐药菌检出未明显改善,需要进一步制定针对性干预措施,促进院感高质量发展。 展开更多
关键词 病原学送检 抗菌药物 干预措施 中断时间序列 医院感染
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抗移频间歇采样转发干扰波形与非匹配滤波器设计方法
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作者 周凯 李超 +3 位作者 李坤 崔新风 姚辉伟 陈冬冬 《系统工程与电子技术》 北大核心 2025年第7期2194-2204,共11页
移频间歇采样转发干扰(shift-frequency interrupted sampling repeater jamming,SFISRJ)兼具两种干扰的优点,严重威胁雷达探测。对此,提出一种基于波形与非匹配滤波器设计的抗SFISRJ方法。兼顾干扰抑制和脉冲压缩性能,建立无约束多目... 移频间歇采样转发干扰(shift-frequency interrupted sampling repeater jamming,SFISRJ)兼具两种干扰的优点,严重威胁雷达探测。对此,提出一种基于波形与非匹配滤波器设计的抗SFISRJ方法。兼顾干扰抑制和脉冲压缩性能,建立无约束多目标联合优化模型,推导目标函数梯度,并提出基于限制内存BFGS(limited-memory Broyden-Fletcher-Goldfarb and Shannon,L-BFGS)的联合设计算法。仿真验证了所提算法的可行性,尤其当真实目标和假目标在时域和时频域不可分离时,所提算法相较于传统方法能够取得最优抗干扰性能。 展开更多
关键词 移频间歇采样转发干扰 波形设计 非匹配滤波器 梯度下降
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基于虚拟编组的城轨线路单向运营中断场景下的列车运行调整研究
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作者 周玮腾 高婕 +3 位作者 韩波 鲁放 韩宝明 胡江枫 《都市快轨交通》 北大核心 2025年第5期72-82,共11页
针对城市轨道交通线路单向运营发生中断时,线网运输能力降低、大面积乘客滞留导致运营安全风险增加的问题,构建基于虚拟编组技术的列车运行调整模型,通过优化模型刻画基于虚拟编组的列车运行调整过程,并结合双层模拟退火-遗传算法进行... 针对城市轨道交通线路单向运营发生中断时,线网运输能力降低、大面积乘客滞留导致运营安全风险增加的问题,构建基于虚拟编组技术的列车运行调整模型,通过优化模型刻画基于虚拟编组的列车运行调整过程,并结合双层模拟退火-遗传算法进行求解。最后,以某城市地铁线路单向中断为例,对本文提出的策略进行验证。研究结果表明:与传统反向行车列车运行调整技术相比,基于虚拟编组技术的列车反向运行调整策略可使乘客总等待时间减少16.4%,乘客在站等待时间减少14.1%,滞留乘客人数明显减少,列车运行调整的灵活性与效率显著提升。研究结果可为运营中断场景下的列车运行调整提供参考。 展开更多
关键词 城市轨道交通 列车运行调整 虚拟编组 单向中断 反向行车
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西安市某污水处理厂不停产提标改造工程设计
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作者 张日霞 王社平 +2 位作者 黄宁俊 尹博涵 王继斌 《中国给水排水》 北大核心 2025年第22期65-71,共7页
西安市某污水处理厂处理规模10×10^(4) m^(3)/d,现状采用氧化沟+纤维转盘滤池为主体的处理工艺,提标改造工程需在不停产的情况下将出水由《城镇污水处理厂污染物排放标准》(GB18918—2002)一级A标准提升至地表水准Ⅳ类标准。通过... 西安市某污水处理厂处理规模10×10^(4) m^(3)/d,现状采用氧化沟+纤维转盘滤池为主体的处理工艺,提标改造工程需在不停产的情况下将出水由《城镇污水处理厂污染物排放标准》(GB18918—2002)一级A标准提升至地表水准Ⅳ类标准。通过综合分析污水处理厂现状构筑物及实测进、出水水质,充分复核生物反应池处理能力,确定对一、二期氧化沟重新配水,新建厌氧池从而增加一期氧化沟总水力停留时间,同时在二沉池后设置高效沉淀池及反硝化深床滤池的工艺方案。工程总投资1.38亿元,于2022年12月通水试车,目前各项出水水质指标稳定达标,可供同类污水处理厂提标改造工程参考。 展开更多
关键词 污水处理厂 不停产 提标改造 地表水准Ⅳ类标准
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农村污水间歇断流下滴滤池效能维持及微生物胞外应激机制
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作者 李亚娇 蒋小雨 +5 位作者 池玉蕾 张彬鸿 任武昂 丁晓倩 鞠恺 金鹏康 《中国环境科学》 北大核心 2025年第5期2434-2442,共9页
间歇断流下微生物的适应恢复能力是滴滤池稳定运行的关键,该过程与微生物以EPS形式储存的活性物质紧密联系.基于此,对比分析滴滤池稳定运行周期内生物膜结构、EPS组分及其官能团的变化特征,探讨了EPS的应激机制同微生物活性维持与恢复... 间歇断流下微生物的适应恢复能力是滴滤池稳定运行的关键,该过程与微生物以EPS形式储存的活性物质紧密联系.基于此,对比分析滴滤池稳定运行周期内生物膜结构、EPS组分及其官能团的变化特征,探讨了EPS的应激机制同微生物活性维持与恢复的关联.结果表明,间歇断流下滴滤池的COD、NH_(4)^(+)-N去除率分别达95.56%±1.10%、87.06%±2.08%;受EPS影响,生物膜呈松散孔隙/紧密堆积的形貌结构;微生物在断流期转化SB-EPS内吸附的碳源与LB-EPS内储存的多糖为营养物质,并依靠EPS内疏水基团与架桥作用维护稳定结构,形成了EPS适应饥饿交替的应激机制,进而维持了滴滤池的稳定运行. 展开更多
关键词 生物滴滤池 间歇断流 生物膜结构 胞外聚合物 应激机制
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主屏蔽罩电位分布对真空灭弧室内部绝缘性能影响
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作者 程显 李冠军 +2 位作者 葛国伟 杜帅 张万隆 《上海交通大学学报》 北大核心 2025年第10期1546-1557,共12页
真空断路器作为一种环保型开关设备,具有广泛的应用前景,但其在单断口和多断口结构中均存在真空灭弧室主屏蔽罩电位分布不均问题,且在罐式结构中该问题更为显著.为研究主屏蔽罩电位分布对真空灭弧室内部绝缘性能的影响,本文建立了真空... 真空断路器作为一种环保型开关设备,具有广泛的应用前景,但其在单断口和多断口结构中均存在真空灭弧室主屏蔽罩电位分布不均问题,且在罐式结构中该问题更为显著.为研究主屏蔽罩电位分布对真空灭弧室内部绝缘性能的影响,本文建立了真空灭弧室主屏蔽罩分压模型,并利用COMSOL软件进行仿真计算.通过在真空灭弧室外侧构造电容以调节主屏蔽罩电位占断口电位的比例,得到主屏蔽罩电位变化对内部电场分布的影响规律.在此基础上,以10kV真空灭弧室为对象,开展不同主屏蔽罩分压比例下的工频耐压与雷电冲击耐压实验.结果表明:真空灭弧室内部电场强度随主屏蔽罩电位的升高呈先下降后上升的趋势,当主屏蔽罩分压为50%时,真空灭弧室内部最大场强达到最小值.实验与仿真结果基本一致:在触头开距为6mm的条件下,主屏蔽罩电位为断口间电位50%时工频击穿电压提高5.4%,雷电冲击电压提高6.7%.本研究为提升真空灭弧室内部绝缘性能以及推动更高电压等级真空断路器的应用提供了参考. 展开更多
关键词 真空灭弧室 主屏蔽罩电位 电场仿真 绝缘性能
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环保型罐式多断口真空断路器气体绝缘与沿面闪络特性
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作者 程显 郭龙雨 +2 位作者 杜帅 葛国伟 鲁文龙 《高电压技术》 北大核心 2025年第6期2620-2630,共11页
随着国家“双碳”政策的提出,采用自然气体绝缘与真空灭弧室开断的环保型罐式真空断路器是高压、超高压领域替代SF6断路器的有效手段,其绝缘气体选型方案与真空灭弧室陶瓷沿面闪络特性尚不清晰。首先进行了自然环保型绝缘气体干燥空气与... 随着国家“双碳”政策的提出,采用自然气体绝缘与真空灭弧室开断的环保型罐式真空断路器是高压、超高压领域替代SF6断路器的有效手段,其绝缘气体选型方案与真空灭弧室陶瓷沿面闪络特性尚不清晰。首先进行了自然环保型绝缘气体干燥空气与CO_(2)雷电冲击绝缘击穿试验,提出了环保型气体绝缘方案。其次,进行了环保型气体绝缘条件下真空灭弧室陶瓷外壳沿面闪络特性研究,并分析了中封环处气体-陶瓷-金属三结合点对沿面闪络特性的影响。结果表明:0.9 MPa干燥空气与0.9 MPa CO_(2)可满足罐式多断口真空断路器绝缘配置要求;真空灭弧室沿面闪络电压随着气压增加而增大并呈现略微饱和趋势,0.9 MPa干燥空气真空灭弧室沿面闪络电压达到202.98 kV,中封环的引入使沿面闪络电压下降8.47%;金属微粒长度5 mm、距离高压端5 mm时陶瓷外壳沿面闪络电压幅值降低相对最大为49.67 kV;中封环的引入使此处表面电荷密度由6.62μC/m^(2)增至21.54μC/m^(2),导致其沿面闪络电压下降。以上结果可为超高压领域发展环保型罐式真空断路器提供理论依据与试验支撑。 展开更多
关键词 环保型绝缘气体 罐式断路器 雷电冲击电压 真空灭弧室 沿面闪络
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