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JR东日本公司的新干线综合运输管理系统(COSMOS) 被引量:22
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作者 村山一雄 邹振民 +1 位作者 赵淑贞 谢肇桐 《中国铁路》 2000年第11期42-45,共4页
介绍了JR东日本旅客公司开发的新干线综合运输管理系统(COSMOS)的各种功能。该系统包括运输计划、运行管理、车站作业管理、维修作业管理、车辆管理、设备管理、信息集中管理和电力系统控制等子系统。
关键词 铁路综合运输管理系统 系统功能 运输计划
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The Citron homology domain of MAP4Ks improves outcomes of traumatic brain injury
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作者 Xiaoling Zhong Wenjiao Tai +4 位作者 Meng-Lu Liu Shuaipeng Ma Tianjin Shen Yuhua Zou Chun-Li Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第11期3233-3244,共12页
The mitogen-activated protein kinase kinase kinase kinases(MAP4Ks)signaling pathway plays a pivotal role in axonal regrowth and neuronal degeneration following insults.Whether targeting this pathway is beneficial to b... The mitogen-activated protein kinase kinase kinase kinases(MAP4Ks)signaling pathway plays a pivotal role in axonal regrowth and neuronal degeneration following insults.Whether targeting this pathway is beneficial to brain injury remains unclear.In this study,we showed that adeno-associated virus-delivery of the Citron homology domain of MAP4Ks effectively reduces traumatic brain injury-induced reactive gliosis,tauopathy,lesion size,and behavioral deficits.Pharmacological inhibition of MAP4Ks replicated the ameliorative effects observed with expression of the Citron homology domain.Mechanistically,the Citron homology domain acted as a dominant-negative mutant,impeding MAP4K-mediated phosphorylation of the dishevelled proteins and thereby controlling the Wnt/β-catenin pathway.These findings implicate a therapeutic potential of targeting MAP4Ks to alleviate the detrimental effects of traumatic brain injury. 展开更多
关键词 adeno-associated virus Citron homology Citron homology domain gene therapy mitogen-activated protein kinase kinase kinase kinases traumatic brain injury
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Determination of main influence mechanism of fulvic acid on arsenic removal by ferric chloride
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作者 Xiaoguang Meng Sihang Xu +6 位作者 Meng Ji Qiantao Shi Biswarup Guha Kelly Mascarenhas Lee Lippincott Wen Zhang Qingquan Ma 《Journal of Environmental Sciences》 2025年第7期22-29,共8页
In this study,synthetic wastewater containing 110μg/L arsenate(As(V)),0-20 mg/L fulvic acid(FA),and 0-12.3 mg/L phosphate was treated with 3 mg/L Fe3+.The mechanisms of FA and phosphate effects on As(V)removal by fer... In this study,synthetic wastewater containing 110μg/L arsenate(As(V)),0-20 mg/L fulvic acid(FA),and 0-12.3 mg/L phosphate was treated with 3 mg/L Fe3+.The mechanisms of FA and phosphate effects on As(V)removal by ferric chloride were determined using 0.22-10μm pore-size filtration,Zetasizer analysis,and in situ flow through cell ATR-FTIR.The results showed that up to 20mg/L FA had almost no effect on the solubility of ferric hydroxide precipitates and adsorption of As(V)by the precipitates.When FA concentration increased from 0 to 20 mg/L,the adsorption of FA led to higher negative zeta potential of the precipitates and the strong electrostatic repulsion between the precipitates decreased the particle size of ferric hydroxide flocs fromlarger than 10μmto smaller than 1μm.In the presence of 5-20 mg/L FA,46%-63%As(V)was adsorbed onto the flocs with particle size in the range of 0.45-1μm.On the other hand,phosphate did not affect the size of ferric hydroxide flocs and significantly increased the dissolved As(V)concentration because it competed with As(V)for adsorption sites on ferric hydroxide precipitates.The addition of 5mg/L cationic organic flocculant significantly reduced the effect of FA on As(V)removal,but did not reduce the effect of phosphate on As(V)removal.The findings of this study will help develop effective arsenic treatment techniques and predict the mobility of arsenic in the environment. 展开更多
关键词 ARSENIC Fulvic acid PHOSPHATE COAGULATION Adsorption Ferric chloride FILTRATION CENTRIFUGATION
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Disparities in liver transplantation for metabolic dysfunctionassociated steatohepatitis-associated hepatocellular carcinoma
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作者 David W Victor Sudha Kodali +13 位作者 Mazen Noureddin Elizabeth W Brombosz Analisa Lopez Tamneet Basra Edward A Graviss Duc T Nguyen Ashish Saharia Ashton A Connor Maen Abdelrahim Yee Lee Cheah Caroline J Simon Mark J Hobeika Constance M Mobley R Mark Ghobrial 《World Journal of Transplantation》 2025年第3期116-127,共12页
BACKGROUND Metabolic dysfunction-associated steatohepatitis(MASH)is increasingly common,as is hepatocellular carcinoma(HCC)in the background of MASH.Liver transplantation(LT)provides superior long-term survival for pa... BACKGROUND Metabolic dysfunction-associated steatohepatitis(MASH)is increasingly common,as is hepatocellular carcinoma(HCC)in the background of MASH.Liver transplantation(LT)provides superior long-term survival for patients with unresectable MASH-HCC,but not all patients have equal access to transplant.MASH-HCC disproportionately affects Hispanic patients,but minorities are less likely to undergo LT for HCC.Additionally,females also undergo LT at lower rates than males.AIM To investigate whether race/ethnicity and sex affect LT waitlist outcomes.METHODS Records of adults with MASH-HCC in the United States Organ Procurement and Transplantation Network database listed for LT between 1/2015 and 12/2021 were analyzed.RESULTS Most of the 3810 patients waitlisted for LT for MASH-HCC were non-Hispanic(NH)white(71.2%)or Hispanic(23.4%),with only 49(1.1%)NH Black candidates.Hispanics underwent LT at lower rates than NH whites(71.6%vs 78.4%,P<0.001),but race/ethnicity did not affect waitlist mortality(P=0.06).Patients with Hispanic[hazard ratio(HR)=0.85,95%CI:0.77-0.95,P=0.002]or Asian(HR=0.79,95%CI:0.63-0.98,P=0.04)race/ethnicity were less likely to undergo LT.Women were also less likely to receive LT(male:HR=1.16,95%CI:1.04-1.29,P=0.01).Patients in regions 1 and 9 were less likely to be transplanted as well(P=0.07).CONCLUSION Hispanic patients are less likely to undergo LT for MASH-HCC,concerning given their susceptibility to MASH and HCC.There were very few NH Black candidates.Disparities were also unequal across regions,which is particularly concerning in states where at-risk populations have rising cancer incidence.Additional research is needed to identify strategies for mitigating these differences in access to LT for MASH-HCC. 展开更多
关键词 Steatotic liver disease Liver neoplasms Ethnic and racial minorities Healthcare disparities Minority health
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Quality of life,dumping symptoms,and weight bias internalization after endoscopic bariatric revisional therapies
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作者 Amulya Agrawal Alvaro Cadillo Arbaiza +4 位作者 Ronald Blanco Montecino Jaime P Almandoz Sarah E Messiah Matthew Mathew Anna Tavakkoli 《World Journal of Gastrointestinal Endoscopy》 2025年第12期156-163,共8页
BACKGROUND Endoscopic bariatric therapies(EBT)have been developed as an adjunctive therapy to treat persistent obesity and recurrent weight gain and dumping symptoms after metabolic and bariatric surgery(MBS).While th... BACKGROUND Endoscopic bariatric therapies(EBT)have been developed as an adjunctive therapy to treat persistent obesity and recurrent weight gain and dumping symptoms after metabolic and bariatric surgery(MBS).While the efficacy of revisional EBTs has been documented,no studies to date have examined how these procedures impact quality of life(QOL)and internalized weight bias(IWB).AIM To understand how endoscopic revisional therapies impact QOL,IWB,and dumping syndrome.METHODS Analysis included 19 participants treated for post-MBS recurrent weight gain and/or dumping syndrome.The short-form 36 survey,weight bias internalization scale,and the Sigstad scoring system were used to measure QOL,IWB,and dumping syndrome pre-and≥4 weeks post-EBT.RESULTS At 6-months,total body weight loss was 8.6%±7.15%(n=16),at 12-months was 13.4%±7.46%(n=16).Short-form 36 scores for all 8 scales significantly increased from pre-to post-procedure with the greatest improvement in the scales related to emotional(mean improvement=59.6,P<0.05)and physical health(mean improvement=31.1,P<0.05).Both total Sigstad score(mean difference=4.947,P<0.05)and total weight bias internalization score(mean difference=0.761,P<0.05)significantly decreased from pre-to post-procedure.CONCLUSION Findings suggest that revisional EBT may improve post-MBS QOL across a broad spectrum of outcomes beyond optimizing body weight.As early EBT results indicate positive mental and physical health outcomes,further research is needed to evaluate the relationship between these improvements,body weight and interdisciplinary post-MBS care. 展开更多
关键词 Endobariatrics Dumping syndrome Bariatric surgery Weight bias Quality of life Transoral outlet reduction Sleeve gastrectomy
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Advantages of new generation colonoscopes on adenoma detection:A propensity-score matching study
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作者 Toshihiro Nishizawa Osamu Toyoshima +7 位作者 Shuntaro Yoshida Yoshiyuki Takahashi Hideki Nakagawa Hiroya Mizutani Yosuke Kataoka Takamitsu Kanazawa Hirotoshi Ebinuma Keisuke Hata 《World Journal of Gastrointestinal Endoscopy》 2025年第6期57-63,共7页
BACKGROUND Recently,Olympus Corporation released new scopes(XZ1200/EZ1500).However,there have been few reports on this topic,although improvement in adenoma detection rate(ADR)by texture and color enhancement imaging(... BACKGROUND Recently,Olympus Corporation released new scopes(XZ1200/EZ1500).However,there have been few reports on this topic,although improvement in adenoma detection rate(ADR)by texture and color enhancement imaging(TXI)or computer-aided detection system(CAD)has been reported.AIM To investigate the effects of the scope on the detection of adenomas and sessile serrated lesions(SSLs).METHODS The subjects were patients who underwent pancolonic chromoendoscopy using the EVIS X1 video system center between May 2023 and October 2024.The patients were divided into the new(CF-XZ1200/CF-EZ1500)and 290 series(CF-HQ290Z/PCF-H290Z)groups.Propensity score matching was performed for age,sex,examination purpose,endoscopist,preparation,TXI use,and CAD use.The effects of the scope were analyzed in terms of the ADR,SSL detection rate(SDR),and mean number of adenomas per colonoscopy(APC).RESULTS Of the 7014 patients enrolled,2138 pairs were extracted by propensity score matching(mean age 55.4 years,45.5%male).The new scopes group had a significantly higher ADR than the 290 series group[51.5%vs 45.5%,odds ratio(OR)=1.27,95%CI:1.13-1.43,P<0.001].Similarly,the new scopes group had significantly higher SDR(7.8%vs 5.7%,OR=1.41,95%CI:1.11-1.80,P=0.005)and APC(0.90 vs 0.76,OR=1.11,95%CI:1.05-1.17,P<0.001)than the 290 series group.CONCLUSION In conclusion,the new scope(CF-XZ1200/CF-EZ1500)enhanced the detection of adenomas and SSLs compared to the old ones(290 series). 展开更多
关键词 COLONOSCOPY New generation Adenoma detection rate Propensity-score matching EVIS X1
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Prognostic factors and efficacy of postoperative chemotherapy in patients with gastric cancer with positive peritoneal cytology after gastrectomy
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作者 Yoichi Sugiyama Kazuaki Tanabe +12 位作者 Senichiro Yanagawa Hirofumi Tazawa Kazuhiro Toyota Mikihiro Kano Toshihiro Misumi Masayuki Shishida Keisuke Okano Ryuichi Hotta Hiroshi Ota Yasuhiro Imaoka Toshikatsu Fukuda Shinya Takahashi Hideki Ohdan 《World Journal of Gastrointestinal Oncology》 2025年第9期132-147,共16页
BACKGROUND Peritoneal lavage cytology-positive(CY1)gastric cancer(stage IV)has a poor prognosis,though some cases fare better.Therefore,identifying prognostic factors and an optimal treatment strategy is crucial.AIM T... BACKGROUND Peritoneal lavage cytology-positive(CY1)gastric cancer(stage IV)has a poor prognosis,though some cases fare better.Therefore,identifying prognostic factors and an optimal treatment strategy is crucial.AIM To investigate prognostic factors in patients with gastric cancer who underwent gastrectomy with CY1,and to evaluate the optimal postoperative chemotherapy regimen.METHODS This multicenter retrospective cohort study analyzed prognostic factors and postoperative chemotherapy in patients with CY1 gastric cancer who underwent gastrectomy,excluding those with macroscopic peritoneal dissemination.Data from 13 institutions(2015-2019)were reviewed.RESULTS Overall,82 patients met the inclusion criteria.The median overall survival was 22.8 months,and diffuse-type histology and the absence of postoperative chemotherapy were identified as independent poor prognostic factors.The 5-year survival rate was 82.4%for those receiving fluoropyrimidine plus docetaxel/oxaliplatin vs 21.8%for those with S-1 monotherapy or a cisplatin-based regimen.Median overall survival was not reached in the fluoropyrimidine+docetaxel/oxaliplatin group but was 22.9 months in the S-1/cisplatin group.Chemotherapy regimen was an independent prognostic factor(hazard ratio=5.47,P=0.004).The fluoropyrimidine plus docetaxel/oxaliplatin group had an average relative dose intensity of 82.1%,with significantly more patients achieving a relative dose intensity≥80%than in the S-1 monotherapy or cisplatin-based group(P=0.001).CONCLUSION Diffuse-type histology and the absence of postoperative chemotherapy influence the prognosis of patients with CY1 gastric cancer.Combination therapy with oxaliplatin or docetaxel may enhance the treatment intensity and improve survival outcomes after gastrectomy. 展开更多
关键词 Gastric cancer Peritoneal lavage cytology-positive CHEMOTHERAPY Prognostic factor Treatment strategy Cancer statistics Survival
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检测基因及样本类型对人感染H7N9禽流感病毒实验室检测结果的影响 被引量:2
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作者 石伟先 潘阳 +6 位作者 赵佳琛 彭晓旻 崔淑娟 卢桂兰 张代涛 刘医萌 王全意 《中华疾病控制杂志》 CAS CSCD 北大核心 2015年第2期111-114,共4页
目的 检测北京市H7N9禽流感病毒感染病例及密切接触者样本中H7N9流感病毒相关基因,分析不同靶基因、不同类型样本对检测结果的影响。方法 收集2013年4月~7月北京市人感染H7N9禽流感病例及密切接触者咽拭子、痰、气管灌洗液、血清样本,... 目的 检测北京市H7N9禽流感病毒感染病例及密切接触者样本中H7N9流感病毒相关基因,分析不同靶基因、不同类型样本对检测结果的影响。方法 收集2013年4月~7月北京市人感染H7N9禽流感病例及密切接触者咽拭子、痰、气管灌洗液、血清样本,提取病毒RNA,检测甲型流感病毒基质蛋白(influenza A matrixprotein,Am)基因、血凝素-7(hemagglutinin7,H7)基因和神经氨酸酶-9(neuraminidase9,N9)基因,并对结果进行统计分析。结果 H7N9禽流感确诊病例样本中Am基因、H7基因和N9基因的检测阳性率分别为68.3%、66.0%和41.5%,N9基因阳性率低于前两者。在定量检测中,Am基因、H7基因和N9基因的定量限分别为10copies/ml、10copies/ml和100copies/ml。在各类型检测样本中,气管灌洗液样本的病毒核酸检出率较高,未在血清和结膜分泌物样本中检出病毒核酸。结论 在人感染H7N9禽流感检测中,应尽量使用气管灌洗液等下呼吸道样本,综合判定检测结果,为临床治疗提供参考依据。 展开更多
关键词 禽流感 基因 病毒 流行病学
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一氧化氮在亚细胞结构精确照射诱导旁效应中的作用 被引量:2
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作者 邵春林 FOLKARD Melvyn PRISE Kevin M 《辐射研究与辐射工艺学报》 CAS CSCD 北大核心 2007年第2期119-123,共5页
研究了肿瘤细胞的亚结构在荷能离子照射下所诱导的旁效应及其信号分子。以氦离子微束装置所产生的精确数量离子定位照射神经胶质瘤细胞T98G细胞核或细胞质,检测细胞染色体损伤和胞内一氧化氮(Nitric Oxide,NO)自由基的产额,探索NO清除... 研究了肿瘤细胞的亚结构在荷能离子照射下所诱导的旁效应及其信号分子。以氦离子微束装置所产生的精确数量离子定位照射神经胶质瘤细胞T98G细胞核或细胞质,检测细胞染色体损伤和胞内一氧化氮(Nitric Oxide,NO)自由基的产额,探索NO清除剂对它们的影响,并以(Diethylamine nitric oxide,DEANO)研究NO的细胞效应。结果表明,无论是细胞核照射还是细胞质照射,只要1个细胞受到1个离子的照射,就可通过损伤的级联放大形成辐射旁效应,引起周围数十个细胞的损伤。对比核、质照射的生物效应,细胞核照射比细胞质照射具有更加显著的直接作用,但这两种照射所诱导的旁效应程度却相当。而NO自由基清除剂c-PTIO(2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide)可抑制旁效应的产生。NO分子探针DAF-FM(4-amino-5-methylamino-2',7'-difluorofluorescein diacetate)原位检测表明,即使只有1%的细胞核或细胞质受到单离子照射,具有NO阴性表达的细胞百分数增加了30%,使NO引起的细胞荧光密度增加15%。DEANO实验表明,NO可引起细胞微核的产生。因此,NO是亚细胞结构照射引起旁效应的一个重要信号因子。 展开更多
关键词 微离子束 亚细胞照射 旁效应 信号因子 一氧化氮
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腋淋巴结阳性乳腺浸润性导管癌差异蛋白的质谱分析 被引量:1
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作者 傅金瑞 王高升 +4 位作者 王学超 张超 张晨磊 王广舜 刘金波 《实用检验医师杂志》 2018年第1期5-9,共5页
目的筛选可能用于判断乳腺浸润性导管癌发生腋淋巴结转移的血清蛋白标志物。方法收集2015年3月—2016年5月天津市宝坻区人民医院收治的乳腺浸润性导管癌患者血清样本24份,按照是否发生腋淋巴结转移分为两组,每组各12份。将每组的12份血... 目的筛选可能用于判断乳腺浸润性导管癌发生腋淋巴结转移的血清蛋白标志物。方法收集2015年3月—2016年5月天津市宝坻区人民医院收治的乳腺浸润性导管癌患者血清样本24份,按照是否发生腋淋巴结转移分为两组,每组各12份。将每组的12份血清等量混合,利用双向凝胶电泳(2D-PAGE)和基质辅助激光解析电离飞行时间质谱(MALDI-TOF-MS)技术鉴定差异蛋白质,对2D-PAGE图谱与MALDI-TOF-MS质谱进行分析。结果 2D-PAGE图谱分析筛选出差异蛋白点11个;经MALDI-TOF-MS质谱分析鉴定出高可信度的蛋白5种,表达上调的为T淋巴瘤侵袭转移诱导因子1(Tiam1)、组织蛋白酶K(Cat K)、血管内皮生长因子B(VEGF-B)、肌动蛋白相关蛋白复合物3(ARPC3),表达下调的为抑癌蛋白Necdin(覆盖率分别为Tiam1蛋白29%,Cat K蛋白12%,VEGF-B蛋白34%,ARPC3蛋白26%,Necdin蛋白18%)。结论乳腺浸润性导管癌发生腋淋巴结转移后其蛋白质表达谱也发生了变化,所鉴定出的差异蛋白有可能成为判断其是否发生腋淋巴结转移的血清蛋白标志物。 展开更多
关键词 乳腺浸润性导管癌 腋淋巴结转移 双向凝胶电泳 基质辅助激光解析电离飞行时间质谱 肽质量指纹谱
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全国产化单纤高功率光纤激光器的研究 被引量:4
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作者 杨敬文 张培培 +5 位作者 吕晓英 韩桂云 张雪莲 王晓龙 张鹏 黄榜才 《激光与红外》 CAS CSCD 北大核心 2018年第3期318-321,共4页
报道了采用国产双包层掺镱光纤搭建的高功率光纤激光器。此光纤激光器采用中国电子科技集团公司第四十六研究所最新研制的20/400双包层掺镱光纤,激光器采用谐振腔振荡方式输出,激光器中心波长为1080 nm,最高输出激光功率为758 W,输出光... 报道了采用国产双包层掺镱光纤搭建的高功率光纤激光器。此光纤激光器采用中国电子科技集团公司第四十六研究所最新研制的20/400双包层掺镱光纤,激光器采用谐振腔振荡方式输出,激光器中心波长为1080 nm,最高输出激光功率为758 W,输出光斑直径6~8 mm,接近准单模输出,光束β因子为1.3。电光转换效率36.7%,光-光转换效率71%,经过32 h的满功率激光输出,平均输出功率波动范围小于2%。 展开更多
关键词 国产双包层掺镱光纤 高功率光纤激光器 激光功率 转换效率
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羽毛球颠球练习对小学生视力的即时干预效果研究
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作者 徐锋鹏 陈妙珊 +3 位作者 Ziyi Yang 杨钢 栾军 蔡祥胜 《体育师友》 2023年第6期30-33,共4页
目的:为探讨羽毛球颠球练习对小学生视力的即时效果,找到一套方便实施的小学生预防近视的运动方法。方法:采用随机对照试验,将54名小学生随机分为羽毛球颠球练习组、羽毛球对打组和跳绳组,分别进行40分钟的练习,观察三组受试者运动前后... 目的:为探讨羽毛球颠球练习对小学生视力的即时效果,找到一套方便实施的小学生预防近视的运动方法。方法:采用随机对照试验,将54名小学生随机分为羽毛球颠球练习组、羽毛球对打组和跳绳组,分别进行40分钟的练习,观察三组受试者运动前后视力变化。结果:羽毛球颠球组和羽毛球对打组的视力前后比较,双眼视力改善均有非常显著性差异(P<0.01),跳绳组干预前后,双眼视力无显著性变化。再对颠球组进行皮尔逊相关性分析,年龄越小,颠球后的视力改善越明显(r=-0.389,P<0.05)。结论:颠球具有较好的即时改善视力效果,且年龄越小,改善效果越好。 展开更多
关键词 羽毛球颠球练习 小学生 视力
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正六棱型MoO_(3-x)微米柱光催化剂的制备及性能 被引量:2
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作者 唐飞 杜多勤 +1 位作者 谭芸妃 秦莉晓 《应用化学》 CAS CSCD 北大核心 2021年第1期92-98,共7页
首先采用低温水相合成法制备了正六棱型MoO_(3)微米柱,然后以抗坏血酸为还原剂一步还原法制备了一种表面氧空位可控的MoO_(3-x)光催化材料。MoO_(3-x)具有较窄的禁带宽度和较大的光吸收范围。以罗丹明B为模拟污染物的光催化降解实验表明... 首先采用低温水相合成法制备了正六棱型MoO_(3)微米柱,然后以抗坏血酸为还原剂一步还原法制备了一种表面氧空位可控的MoO_(3-x)光催化材料。MoO_(3-x)具有较窄的禁带宽度和较大的光吸收范围。以罗丹明B为模拟污染物的光催化降解实验表明,随着氧空位的增加,MoO_(3-x)的催化活性明显增加。对于Mo^(5+)摩尔分数为20.1%的MoO2.799样品,降解90%的初始质量浓度为10 mg/L的罗丹明溶液只需要60 min。本研究为高性能半导体光催化材料的制备提供了一种新思路。 展开更多
关键词 MoO_(3-x) 正六棱型MoO_(3)微米柱 氧空位 光催化
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基于状态空间模型的飞行器装配误差敏感度研究 被引量:2
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作者 孙崇飞 李欣 +3 位作者 朱一鸣 尚建忠 罗自荣 何立军 《农业机械学报》 EI CAS CSCD 北大核心 2020年第5期421-426,共6页
飞行器具有零部件多、结构复杂和装配精度要求高等特点,其装配有安全性装配、少可逆性装配等要求。根据飞行器相关的关键产品特性(Key product characteristic,KPC)和关键控制特性(Key control characteristic,KCC)参数,提出一种基于状... 飞行器具有零部件多、结构复杂和装配精度要求高等特点,其装配有安全性装配、少可逆性装配等要求。根据飞行器相关的关键产品特性(Key product characteristic,KPC)和关键控制特性(Key control characteristic,KCC)参数,提出一种基于状态空间模型的装配误差敏感度量化分析方法,将飞行器多舱段精密装配过程中的误差敏感度分为3级指标,并进行阐述和定义。通过联立飞行器状态空间模型和输出方程,得到输入向量和输入矩阵的关系,进而求出状态转换矩阵,得到不同级别误差敏感度的理论表达式。将随机产生服从正态分布的装配特征误差代入系统矩阵,运用蒙特卡洛(Monte Carlo)仿真对不同装配特征的敏感度指标进行计算,并对比分析理论计算和蒙特卡洛仿真求得的特征级敏感度指标值。研究表明,将动态系统灵敏度分析方法应用到多工位装配过程可行,所提出的基于状态空间模型的飞行器装配误差敏感度分析方法合理,对飞行器舱段精密装配过程的精度评估具有参考意义。 展开更多
关键词 飞行器 装配误差敏感度 状态空间模型 关键产品特性 关键控制特性
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Role of endoscopic ultrasound during hospitalization for acute pancreatitis 被引量:6
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作者 Vikram Kotwal Rupjyoti Talukdar +1 位作者 Michael Levy Santhi Swaroop Vege 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第39期4888-4891,共4页
Endoscopic ultrasound(EUS)is often used to detect the cause of acute pancreatitis(AP)after the acute attack has subsided.The limited data on its role during hospitalization for AP are reviewed here.The ability of EUS ... Endoscopic ultrasound(EUS)is often used to detect the cause of acute pancreatitis(AP)after the acute attack has subsided.The limited data on its role during hospitalization for AP are reviewed here.The ability of EUS to visualize the pancreas and bile duct,the sonographic appearance of the pancreas,correlation of such appearance to clinical outcomes and the impact on AP management are analyzed from studies.The most important indication for EUS appears to be for detection of suspected common bile duct and/or gall bladder stones and microlithiasis.Such an approach might avoid diagnostic endoscopic retrograde cholangio-pancreatography with its known complications.The use of EUS during hospitalization for AP still appears to be infrequent but may become more frequent in future. 展开更多
关键词 ACUTE PANCREATITIS ENDOSCOPIC ultrasound ACUTE biliary PANCREATITIS ENDOSCOPIC RETROGRADE cholangio-pancreatography IDIOPATHIC PANCREATITIS
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日本铁路客票预订和发售综合系统(MARS) 被引量:1
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作者 胁田康幸 邹振民 《中国铁路》 1999年第2期42-46,共5页
介绍了日本铁路客票预订和发售综合系统(MARS)的发展简史、现状,并作了展望。
关键词 日本 铁路 额票预订 客票发售 MARS 现代化
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Management and prevention of acute and chronic lateral ankle instability in athletic patient populations 被引量:22
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作者 Brendan J Mc Criskin Kenneth L Cameron +1 位作者 Justin D Orr Brian R Waterman 《World Journal of Orthopedics》 2015年第2期161-171,共11页
Acute and chronic lateral ankle instability are common in high-demand patient populations. If not managed appropriately, patients may experience recurrent instability, chronic pain, osteochondral lesions of the talus,... Acute and chronic lateral ankle instability are common in high-demand patient populations. If not managed appropriately, patients may experience recurrent instability, chronic pain, osteochondral lesions of the talus, premature osteoarthritis, and other significantlong-term disability. Certain populations, including young athletes, military personnel and those involved in frequent running, jumping, and cutting motions, are at increased risk. Proposed risk factors include prior ankle sprain, elevated body weight or body mass index, female gender, neuromuscular deficits, postural imbalance, foot/ankle malalignment, and exposure to at-risk athletic activity. Prompt, accurate diagnosis is crucial, and evidence-based, functional rehabilitation regimens have a proven track record in returning active patients to work and sport. When patients fail to improve with physical therapy and external bracing, multiple surgical techniques have been described with reliable results, including both anatomic and nonanatomic reconstructive methods. Anatomic repair of the lateral ligamentous complex remains the gold standard for recurrent ankle instability, and it effectively restores native ankle anatomy and joint kinematics while preserving physiologic ankle and subtalar motion. Further preventative measures may minimize the risk of ankle instability in athletic cohorts, including prophylactic bracing and combined neuromuscular and proprioceptive training programs. These interventions have demonstrated benefit in patients at heightened risk for lateral ankle sprain and allow active cohorts to return to full activity without adversely affecting athletic performance. 展开更多
关键词 ANKLE instability ATHLETE Treatment Epidemiology PREVENTION LATERAL SPRAIN
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Coronary spasm: It's common, but it's still unsolved 被引量:10
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作者 Hiroki Teragawa Chikage Oshita Tomohiro Ueda 《World Journal of Cardiology》 CAS 2018年第11期201-209,共9页
Coronary spasm is caused by a transient coronary nar -rowing due to the constriction of epicardial coronary artery, which leads to myocardial ischemia. More than 50 years have passed since the first recognition of cor... Coronary spasm is caused by a transient coronary nar -rowing due to the constriction of epicardial coronary artery, which leads to myocardial ischemia. More than 50 years have passed since the first recognition of coronary spasm, and many findings on coronary spasm have been reported. Coronary spasm has been considered as having pivotal roles in the cause of not only rest angina but also exertional angina, acute coronary syndrome, and heart failure. In addition, several new findings of the mechanism of coronary spasm have emerged recently. The diagnosis based mainly on coronary angiography and spasm provo-cation test and the mainstream treatment with a focus on a calcium-channel blocker have been established. At a glance, coronary spasm or vasospastic angina(VSA) has become a common disease. On the contrary, there are several uncertain or unsolved problems regarding coronary spasm, including the presence of medically refractory coronary spasm(intractable VSA), or an appropriate use of implantable cardioverter defibrillator in patients with cardiac arrest who have been confirmed as having coronary spasm. This editorial focused on coronary spasm, including recent topics and unsolved problems. 展开更多
关键词 Vasospastic angina Medically refractory coronary spasm Variant angina Coronary vasospasm
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Role of surgical resection for non-colorectal non-neuroendocrine liver metastases 被引量:6
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作者 Nobuyuki Takemura Akio Saiura 《World Journal of Hepatology》 CAS 2017年第5期242-251,共10页
It is widely accepted that the indications for hepatectomy in colorectal cancer liver metastases and liver metastases of neuro-endocrine tumors result in relatively better prognoses, whereas, the indications and progn... It is widely accepted that the indications for hepatectomy in colorectal cancer liver metastases and liver metastases of neuro-endocrine tumors result in relatively better prognoses, whereas, the indications and prognoses of hepatectomy for non-colorectal non-neuroendocrine liver metastases(NCNNLM) remain controversial owing to the limited number of cases and the heterogeneity of the primary diseases. There have been many publications on NCNNLM; however, its background heterogeneity makes it difficult to reach a specific conclusion. This heterogeneous disease group should be discussed in the order from its general to specific aspect. The present review paper describes the general prognosis and risk factors associated with NCNNLM while specifically focusing on the liver metastases of each primary disease. A multidisciplinary approach that takes into consideration appropriate timing for hepatectomy combined with chemotherapy may prolong survival and/or contribute to the improvement of the quality of life while giving respite from systemic chemotherapy. 展开更多
关键词 Non-colorectal non-neuroendocrine liver metastasis Metastatic liver tumor Hepatectomy Gastric cancer liver metastasis Gastrointestinal stromal tumor liver metastasis Breast cancer liver metastasis Melanoma liver metastasis Sarcoma liver metastasis Renal cell carcinoma liver metastasis Ovarian cancer liver metastasis
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Rare Earths and Magnetic Refrigeration 被引量:20
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作者 Karl A Gschneidner Vitalij K Pecharsky 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第6期641-647,共7页
Magnetic refrigeration is a revolutionary, efficient, environmentally friendly cooling technology, which is on the threshold of commercialization. The magnetic rare earth materials are utilized as the magnetic refrige... Magnetic refrigeration is a revolutionary, efficient, environmentally friendly cooling technology, which is on the threshold of commercialization. The magnetic rare earth materials are utilized as the magnetic refrigerants in most cooling devices, and for many cooling application the Nd2Fe14B permanent magnets are employed as the source of the magnetic field. The status of the near room temperature magnetic cooling was reviewed. 展开更多
关键词 magnetic refrigeration magnetocaloric effect GADOLINIUM Gd5 Si1- x Gex 4 La Fe 13 - x Six Hy Nd2 Fe14 B permanent magnets active magnetic regenerator cycle rare earths
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