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Foam rolling and stretching do not provide superior acute flexibility and stiffness improvements compared to any other warm-up intervention: A systematic review with meta-analysis 被引量:1
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作者 Konstantin Warneke Gerit Plöschberger +5 位作者 Lars H.Lohmann Eric Lichtenstein Daniel Jochum Stanislav D.Siegel Astrid Zech David G.Behm 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第4期509-520,共12页
Background:Acute improvement in range of motion(ROM)is a widely reported effect of stretching and foam rolling,which is commonly explained by changes in pain threshold and/or musculotendinous stiffness.Interestingly,t... Background:Acute improvement in range of motion(ROM)is a widely reported effect of stretching and foam rolling,which is commonly explained by changes in pain threshold and/or musculotendinous stiffness.Interestingly,these effects were also reported in response to various other active and passive interventions that induce responses such as enhanced muscle temperature.Therefore,we hypothesized that acute ROM enhancements could be induced by a wide variety of interventions other than stretching or foam rolling that promote an increase in muscle temperature.Methods:After a systematic search in PubMed,Web of Science,and SPORTDiscus databases,38 studies comparing the effects of stretching and foam rolling with several other interventions on ROM and passive properties were included.These studies had 1134 participants in total,and the data analysis resulted in 140 effect sizes(ESs).ES calculations were performed using robust variance estimation model with R-package.Results:Study quality of the included studies was classified as fair(PEDro score=4.58)with low to moderate certainty of evidence.Results showed no significant differences in ROM(ES=0.01,p=0.88),stiffness(ES=0.09,p=0.67),or passive peak torque(ES=-0.30,p=0.14)between stretching or foam rolling and the other identified activities.Funnel plots revealed no publication bias.Conclusion:Based on current literature,our results challenge the established view on stretching and foam rolling as a recommended component of warm-up programs.The lack of significant difference between interventions suggests there is no need to emphasize stretching or foam rolling to induce acute ROM,passive peak torque increases,or stiffness reductions. 展开更多
关键词 Range of motion Passive properties Muscletendon unit Muscle tissue
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Risk factors and outcome of bacterial infections in cirrhosis 被引量:24
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作者 Tony Bruns Henning W Zimmermann Andreas Stallmach 《World Journal of Gastroenterology》 SCIE CAS 2014年第10期2542-2554,共13页
Viable and non-viable pathological bacterial translocation promote a self-perpetuating circle of dysfunctional immune activation and systemic inflammation facilitating infections and organ failure in advanced cirrhosi... Viable and non-viable pathological bacterial translocation promote a self-perpetuating circle of dysfunctional immune activation and systemic inflammation facilitating infections and organ failure in advanced cirrhosis.Bacterial infections and sepsis are now recognized as a distinct stage in the natural progression of chronic liver disease as they accelerate organ failure and contribute to the high mortality observed in decompensated cirrhosis.The increasing knowledge of structural,immunological and hemodynamic pathophysiology in advanced cirrhosis has not yet translated into significantly improved outcomes of bacterial infections over the last decades.Therefore,early identification of patients at the highest risk for developing infections and infectionrelated complications is required to tailor the currently available measures of surveillance,prophylaxis and therapy to the patients in need in order to improve the detrimental outcome of bacterial infections in cirrhosis. 展开更多
关键词 IMMUNITY INFECTION CIRRHOSIS Chronic liver disease Bacterial translocation Risk factors MORTALITY
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Contrast-enhanced endoscopic ultrasound in discrimination between focal pancreatitis and pancreatic cancer 被引量:43
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作者 Michael Hocke Ewald Schulze +2 位作者 Peter Gottschalk Theodor Topalidis Christoph F Dietrich 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第2期246-250,共5页
AIM: To evaluate the contrast-enhanced endosonography as a method of differentiating inflammation from pancreatic carcinoma based on perfusion characteristics of microvessels. METHODS: In 86 patients with suspected ... AIM: To evaluate the contrast-enhanced endosonography as a method of differentiating inflammation from pancreatic carcinoma based on perfusion characteristics of microvessels. METHODS: In 86 patients with suspected chronic pancreatitis (age: 62± 12 years; sex: f/m 38/48), pancreatic lesions were examined by conventional endo- scopic B-mode, power Doppler ultrasound and contrastenhanced power mode (Hitachi EUB 525, SonoVue, 2.4 mL, Bracco) using the following criteria for malignant lesions: no detectable vascularisation using conventional power Doppler scanning, irregular appearance of arterial vessels over a short distance using SonoVue contrastenhanced technique and no detectable venous vessels inside the lesion. A malignant lesion was assumed if all criteria were detectable [gold standard endoscopic ultrasound (EUS)-guided fine needle aspiration cytology, operation]. The criteria of chronic pancreatitis without neoplasia were defined as no detectable vascularisation before injection of SonoVue, regular appearance of vessels over a distance of at least 20 mm after injection of SonoVue and detection of arterial and venous vessels. RESULTS: The sensitivity and specifidty of conventional EUS were 73.2% and 83.3% respectively for pancreatic cancer. The sensitivity of contrast-enhanced EUS increased to 91.1% in 51 of 56 patients with malignant pancreatic lesion and the specificity increased to 93.3% in 28 of 30 patients with chronic inflammatory pancreatic disease.CONCLUSION: Contrast-enhanced endoscopic ultrasound improves the differentiation between chronic pancreatitis and pancreatic carcinoma. 展开更多
关键词 Endoscopic ultrasound Contrast enhancer Chronic pancreatitis Pancreatic cancer
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Herbal traditional Chinese medicine and its evidence base in gastrointestinal disorders 被引量:21
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作者 Rolf Teschke Albrecht Wolff +2 位作者 Christian Frenzel Axel Eickhoff Johannes Schulze 《World Journal of Gastroenterology》 SCIE CAS 2015年第15期4466-4490,共25页
Herbal traditional Chinese medicine(TCM) is used to treat several ailments, but its efficiency is poorly documented and hence debated, as opposed to modern medicine commonly providinge ffective therapies. The aim of t... Herbal traditional Chinese medicine(TCM) is used to treat several ailments, but its efficiency is poorly documented and hence debated, as opposed to modern medicine commonly providinge ffective therapies. The aim of this review article is to present a practical reference guide on the role of herbal TCM in managing gastrointestinal disorders, supported by systematic reviews and evidence based trials. A literature search using herbal TCM combined with terms for gastrointestinal disorders in Pub Med and the Cochrane database identified publications of herbal TCM trials. Results were analyzed for study type, inclusion criteria, and outcome parameters. Quality of placebo controlled, randomized, double-blind clinical trials was poor, mostly neglecting stringent evidence based diagnostic and therapeutic criteria. Accordingly, appropriate Cochrane reviews and meta-analyses were limited and failed to support valid, clinically relevant evidence based efficiency of herbal TCM in gastrointestinal diseases, including gastroesophageal reflux disease, gastric or duodenal ulcer, dyspepsia, irritable bowel syndrome, ulcerative colitis, and Crohn's disease. In conclusion, the use of herbal TCM to treat various diseases has an interesting philosophical background with a long history, but it received increasing skepticism due to the lack of evidence based efficiency as shown by high quality trials; this has now been summarized for gastrointestinal disorders, with TCM not recommended for most gastrointestinal diseases. Future studies should focus on placebo controlled, randomized, double-blind clinical trials, herbal product quality and standard criteria for diagnosis, treatment, outcome, and assessment of adverse herb reactions. This approach will provide figures of risk/benefit profiles that hopefully are positive for at least some treatment modalities of herbal TCM. Proponents of modern herbal TCM best face these promising challenges of pragmaticmodern medicine by bridging the gap between the two medicinal cultures. 展开更多
关键词 EVIDENCE based trials TRADITIONAL Chinesemedicine HERBAL TRADITIONAL CHINESE MEDICINE Gastrointestinaldisorders
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Drug and herb induced liver injury: Council for International Organizations of Medical Sciences scale for causality assessment 被引量:11
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作者 Rolf Teschke Albrecht Wolff +3 位作者 Christian Frenzel Alexander Schwarzenboeck Johannes Schulze Axel Eickhoff 《World Journal of Hepatology》 CAS 2014年第1期17-32,共16页
Causality assessment of suspected drug induced liver injury(DILI) and herb induced liver injury(HILI) is hampered by the lack of a standardized approach to be used by attending physicians and at various subsequent eva... Causality assessment of suspected drug induced liver injury(DILI) and herb induced liver injury(HILI) is hampered by the lack of a standardized approach to be used by attending physicians and at various subsequent evaluating levels. The aim of this review was to analyze the suitability of the liver specific Council for International Organizations of Medical Sciences(CIOMS) scale as a standard tool for causality assessment in DILI and HILI cases. PubMed database was searched for the following terms: drug induced liver injury; herb induced liver injury; DILI causality assessment; and HILI causality assessment. The strength of the CIOMS lies in its potential as a standardized scale for DILI and HILI causality assessment. Other advantages include its liver specificity and its validation for hepatotoxicity with excellent sensitivity, specificity and predictive validity, based on cases with a positive reexposure test. This scale allows prospective collection of all relevant data required for a valid causality assessment. It does not require expert knowledge in hepatotoxicity and its results may subsequently be refined. Weaknesses of the CIOMS scale include the limited exclusion of alternative causes and qualitatively graded risk factors. In conclusion, CIOMS appears to be suitable as a standard scale for attending physicians, regulatory agencies, expert panels and other scientists to provide a standardized, reproducible causality assessment in suspected DILI and HILI cases, applicable primarily at all assessing levels involved. 2014 Baishideng Publishing Group Co., Limited. All 展开更多
关键词 DRUG INDUCED LIVER INJURY DRUG hepatotox-icity HERB INDUCED LIVER INJURY Herbal HEPATOTOXICITY Causality assessment
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Non-tidal tilt and strain signals recorded at the Geodynamic Observatory Moxa,Thuringia/Germany 被引量:3
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作者 Th.Jahr 《Geodesy and Geodynamics》 2018年第3期229-236,共8页
Since end of the 90s of the last century the seismological station Moxa was extended and developed into the modern Geodynamic Observatory. It comprises also the new installation of borehole-tilt meters in front of the... Since end of the 90s of the last century the seismological station Moxa was extended and developed into the modern Geodynamic Observatory. It comprises also the new installation of borehole-tilt meters in front of the observatory building and laser-strain meters in the gallery. The question arises how non-tidal signals are displayed in the measured time series. The investigation of such signals which can be caused naturally or man-made, can result in different sensitivities for the various tilt- and strainmeter systems, e.g. regarding barometric pressure impacts and hydrological induced pore pressure effects. 展开更多
关键词 Tilt and strain observations Non-tidal effects Man-made effects Pore-pressureInduced tilt and strain Geodynamic Observatory
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知识管理的成功因素-一个实证研究现状的综合分析 被引量:3
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作者 R.Meckl R.Helm 《科研管理》 CSSCI 北大核心 2004年第z1期133-139,共7页
知识管理领域的15年国际研究过程中,虽然出现了大量的相关概念、建议及特定的实践模型,然而关于知识管理的成功因素至今还没有达成共识。本研究通过中间分析法,收集了大量的关于知识管理方面的研究,目的是找出成功进行知识管理的一系列... 知识管理领域的15年国际研究过程中,虽然出现了大量的相关概念、建议及特定的实践模型,然而关于知识管理的成功因素至今还没有达成共识。本研究通过中间分析法,收集了大量的关于知识管理方面的研究,目的是找出成功进行知识管理的一系列决定因素,并给出关于成功因素特征的相关建议。 展开更多
关键词 知识管理 综合分析 实践研究 成功因素
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Interleukin-22 receptor 1 is expressed in multinucleated giant cells:A study on intestinal tuberculosis and Crohn’s disease 被引量:5
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作者 Zi-Qi Yu Wen-Fei Wang +2 位作者 You-Chao Dai Xin-Chun Chen Jian-Yong Chen 《World Journal of Gastroenterology》 SCIE CAS 2019年第20期2473-2488,共16页
BACKGROUND It is challenging to distinguish intestinal tuberculosis from Crohn’s disease due to dynamic changes in epidemiology and similar clinical characteristics. Recent studies have shown that polymorphisms in ge... BACKGROUND It is challenging to distinguish intestinal tuberculosis from Crohn’s disease due to dynamic changes in epidemiology and similar clinical characteristics. Recent studies have shown that polymorphisms in genes involved in the interleukin (IL)- 23/IL-17 axis may affect intestinal mucosal immunity by affecting the differentiation of Th17 cells. AIM To investigate the specific single-nucleotide polymorphisms (SNPs) in genes involved in the IL-23/IL-17 axis and possible pathways that affect susceptibility to intestinal tuberculosis and Crohn's disease. METHODS We analysed 133 patients with intestinal tuberculosis, 128 with Crohn’s disease, and 500 normal controls. DNA was extracted from paraffin-embedded specimens or whole blood. Four SNPs in the IL23/Th17 axis (IL22 rs2227473, IL1β rs1143627, TGFβ rs4803455, and IL17 rs8193036) were genotyped with TaqMan assays. The transcriptional activity levels of different genotypes of rs2227473 were detected by dual luciferase reporter gene assay. The expression of IL-22R1 in different intestinal diseases was detected by immunohistochemistry. RESULTS The A allele frequency of rs2227473 (P = 0.030, odds ratio = 0.60, 95% confidence interval: 0.37-0.95) showed an abnormal distribution between intestinal tuberculosis and healthy controls. The presence of the A allele was associated with a higher IL-22 transcriptional activity (P < 0.05). In addition, IL-22R1 was expressed in intestinal lymphoid tissues, especially under conditions of intestinal tuberculosis, and highly expressed in macrophage-derived Langhans giant cells. The results of immunohistochemistry showed that the expression of IL-22R1 in patients with Crohn's disease and intestinal tuberculosis was significantly higher than that in patients with intestinal polyps and colon cancer (P < 0.01). CONCLUSION High IL-22 expression seems to be a protective factor for intestinal tuberculosis. IL-22R1 is expressed in Langhans giant cells, suggesting that the IL-22/IL-22R1 system links adaptive and innate immunity. 展开更多
关键词 Crohn's disease INTESTINAL tuberculosis Single-nucleotide polymorphism INTERLEUKIN-22 INTERLEUKIN-22 RECEPTOR 1 Multinucleated giant cells
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Complexity of vitamin E metabolism 被引量:4
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作者 Lisa Schmolz Marc Birringer +1 位作者 Stefan Lorkowski Maria Wallert 《World Journal of Biological Chemistry》 CAS 2016年第1期14-43,共30页
Bioavailability of vitamin E is influenced by several factors, most are highlighted in this review. While gender, age and genetic constitution influence vitamin E bioavailability but cannot be modified, life-style and... Bioavailability of vitamin E is influenced by several factors, most are highlighted in this review. While gender, age and genetic constitution influence vitamin E bioavailability but cannot be modified, life-style and intake of vitamin E can be. Numerous factors must be taken into account however, i.e., when vitamin E is orally administrated, the food matrix may contain competing nutrients. The complex metabolic processes comprise intestinal absorption, vascular transport, hepatic sorting by intracellular binding proteins, such as the significant α-tocopherol-transfer protein, and hepatic metabolism. The coordinated changes involved in the hepatic metabolism of vitamin E provide an effective physiological pathway to protect tissues against the excessive accumulation of, in particular, non-α-tocopherol forms. Metabolism of vitamin E begins with one cycle of CYP4F2/CYP3A4-dependent ω-hydroxylation followed by five cycles of subsequent β-oxidation, and forms the water-soluble end-product carboxyethylhydroxychroman. All known hepatic metabolites can be conjugated and are excreted, depending on the length of their sidechain, either via urine or feces. The physiological handling of vitamin E underlies kinetics which vary between the different vitamin E forms. Here, saturation of the side-chain and also substitution of the chromanol ring system are important. Most of the metabolic reactions and processes that are involved with vitamin E are also shared by other fat soluble vitamins. Influencing interactions with other nutrients such as vitamin K or pharmaceuticals are also covered by this review. All these processes modulate the formation of vitamin E metabolites and their concentrations in tissues and body fluids. Differences in metabolism might be responsible for the discrepancies that have been observed in studies performed in vivo and in vitro using vitamin E as a supplement or nutrient. To evaluate individual vitamin E status, the analytical procedures used for detecting and quantifying vitamin E and its metabolites are crucial. The latest methods in analytics are presented. 展开更多
关键词 Vitamin E metabolism Long-chain metabolites of vitamin E Vitamin E bioavailability Vitamin E transport
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弯晶X射线光学(英文) 被引量:2
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作者 E Frster 《光学精密工程》 EI CAS CSCD 北大核心 2007年第12期1823-1828,共6页
近年来,人们付出很大精力研制新的具有独特性能的同步辐射装置和自由电子激光器,而飞秒激光等离子源可提供具有高峰值亮度的超短X射线脉冲,用来作为波荡器辐射的补充X射线源。此外,所有最新型的X射线源的诊断和应用也都需要专用X射线光... 近年来,人们付出很大精力研制新的具有独特性能的同步辐射装置和自由电子激光器,而飞秒激光等离子源可提供具有高峰值亮度的超短X射线脉冲,用来作为波荡器辐射的补充X射线源。此外,所有最新型的X射线源的诊断和应用也都需要专用X射线光学元件或仪器。X射线光谱测量是激光聚变应用中最重要的等离子诊断方法之一,该方法根据实验目的,可获得单色X射线图像或与空间或时间分辨相组合的高分辨率图像。已经研制出拥有多达10个环状弯晶的高精单色成像仪,用以研究激光聚变实验中的内爆过程并通过获得的数据对等离子体参数的时间分辨图做出评估。大功率飞秒激光器可提供实用的相对价格不高的大功率X射线脉冲源,但需要有发光效率,能量分布,以及热电子传输方面的信息来实现理想K层辐射线或者连续X射线输出的最大化,以便得到相当于同步辐射输出的峰值亮度。把这些新的射线源与弯晶光学元件相组合,可完成亚皮秒时间量级的衍射实验。激光泵浦的X射线探针实验已经展示了若干晶体在250 fs内的结构变化。作者所在研究所使用光线追踪和布拉格反射方法设计了1D或2D或1D与2D结合的弯晶X射线光学仪器。在仪器制备过程中,非常注重晶体完整,反射选择的优化,弯曲精确,以及成像和反射特性的测量,还使用X射线形貌相机和衍射仪对分析器晶体的相关特性做了测试。 展开更多
关键词 X射线光学 弯晶 X射线诊断 激光产生等离子体 X射线衍射
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Perovskites for Laser and Detector Applications 被引量:4
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作者 Saunak Das Somayeh Gholipour Michael Saliba 《Energy & Environmental Materials》 SCIE 2019年第2期146-153,共8页
Perovskite materials have triggered a renewed interest in photovoltaic research in the recent years.They display crystal forms with 0D,1D and 2D,3D motifs,and several chemical forms,namely inorganic(titanates,rubidiat... Perovskite materials have triggered a renewed interest in photovoltaic research in the recent years.They display crystal forms with 0D,1D and 2D,3D motifs,and several chemical forms,namely inorganic(titanates,rubidiates,nobiates,tantalates etc.),organic/inorganic metal halides with single to multiple cations,and even organic polymer or quantum dot-infused hybrids.Each crystal type and chemical form are endowed with specific physicochemical,optical,electronic,and morphological properties.These unique properties render them suitable for targeted applications,namely photovoltaics,LEDs,photocatalysis/electrolysis/solar fuels/solar and Li-ion batteries,gas-sensors,ferroelectrics,capacitors,transistors and memristors,photodetectors,and lasers,for advanced quantum cryptography and outer space applications.At first,the crystal and material types,and physicochemical,morphological,and optoelectronic properties of perovskite materials are discussed.Particularly,we focus on those properties which cumulatively contribute to their application in the abovementioned fields.Simultaneously,a comprehensive discussion about the advances in each field is presented.Structure/property/application relationships with key advances demonstrate the versatility of perovskites in modern optoelectronic technologies. 展开更多
关键词 2D perovskites hybrid perovskites micro-lasers X-ray detectors c-ray detectors
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Fatty acid metabolism and acyl-CoA synthetases in the liver-gut axis 被引量:2
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作者 Yunxia Ma Miljana Nenkov +3 位作者 Yuan Chen Adrian T Press Elke Kaemmerer Nikolaus Gassler 《World Journal of Hepatology》 2021年第11期1512-1533,共22页
Fatty acids are energy substrates and cell components which participate in regulating signal transduction,transcription factor activity and secretion of bioactive lipid mediators.The acyl-CoA synthetases(ACSs)family c... Fatty acids are energy substrates and cell components which participate in regulating signal transduction,transcription factor activity and secretion of bioactive lipid mediators.The acyl-CoA synthetases(ACSs)family containing 26 family members exhibits tissue-specific distribution,distinct fatty acid substrate preferences and diverse biological functions.Increasing evidence indicates that dysregulation of fatty acid metabolism in the liver-gut axis,designated as the bidirectional relationship between the gut,microbiome and liver,is closely associated with a range of human diseases including metabolic disorders,inflammatory disease and carcinoma in the gastrointestinal tract and liver.In this review,we depict the role of ACSs in fatty acid metabolism,possible molecular mechanisms through which they exert functions,and their involvement in hepatocellular and colorectal carcinoma,with particular attention paid to long-chain fatty acids and small-chain fatty acids.Additionally,the liver-gut communication and the liver and gut intersection with the microbiome as well as diseases related to microbiota imbalance in the liver-gut axis are addressed.Moreover,the development of potentially therapeutic small molecules,proteins and compounds targeting ACSs in cancer treatment is summarized. 展开更多
关键词 Long-chain fatty acids Short-chain fatty acids Acyl-CoA synthetases MICROBIOTA Liver-gut axis
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Fabrication and characterization of rugate structures composed of SiO_(2) and Nb_(2)O_(5) 被引量:2
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作者 R.Leitel O.Stenzel +3 位作者 S.Wilbrandt D.Gäbler V.Janicki N.Kaiser 《光学精密工程》 EI CAS CSCD 北大核心 2005年第4期505-511,共7页
Gradient index layers and rugate structures were fabricated on a Leybold Syrus pro deposition system by plasma-assisted coevaporation of the low index material silica and the high index material niobium pentoxide.To o... Gradient index layers and rugate structures were fabricated on a Leybold Syrus pro deposition system by plasma-assisted coevaporation of the low index material silica and the high index material niobium pentoxide.To obtain information about the compositional profiles of the produced layers,cross sectional transmission electron microscopy was used in assistance to deposition rate data recorded by two independent crystal monitors during the film preparation.The depth dependent concentration profiles were transformed to refractive index gradients by means of effective medium approximation.Based on the refractive index gradients the corresponding samples`transmission and reflection spectra could be calculated by utilizing matrix formalism.The relevance of the established refractive index profiles could be verified by comparison of the calculated spectra with the measured ones. 展开更多
关键词 physical vapor deposition effective medium approximation rugate structure
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Embolization of an unusual metastatic site of hepatocellular carcinoma in the humerus 被引量:1
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作者 Andreas Hansch Rotraud Neumann +4 位作者 Alexander Pfeil Ivan Marintchev Stefan Pfleiderer Mieczyslaw Gajda Werner A Kaiser 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第18期2280-2282,共3页
Hepatocellular carcinoma (HCC) is the fish most common cancer in the world. This case documents an unusual metastatic presentation of HCC in the humerus. Preoperative palliative arterial embolization of the tumor wa... Hepatocellular carcinoma (HCC) is the fish most common cancer in the world. This case documents an unusual metastatic presentation of HCC in the humerus. Preoperative palliative arterial embolization of the tumor was performed to arrest severe tumor bleeding caused by the biopsy. Embolization turned out to be useful also in limiting/preventing potential uncontrolled bleeding during subsequent amputation. 展开更多
关键词 Hepatocellular carcinoma HUMERUS Upperarm METASTASIS EMBOLIZATION
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Nonlinear frequency conversion in optical nanoantennas and metasurfaces:materials evolution and fabrication 被引量:10
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作者 Mohsen Rahmani Giuseppe Leo +14 位作者 Igal Brener Anatoly V. Zayats Stefan A. Maier Costantino De Angelis Hoe Tan Valerio Flavio Gili Fouad Karouta Rupert Oulton Kaushal Vora Mykhaylo Lysevych Isabelle Staude Lei Xu Andrey E. Miroshnichenko Chennupati Jagadish Dragomir N. Neshev 《Opto-Electronic Advances》 2018年第10期1-12,共12页
Nonlinear frequency conversion is one of the most fundamental processes in nonlinear optics.It has a wide range of applications in our daily lives,including novel light sources,sensing,and information processing.It is... Nonlinear frequency conversion is one of the most fundamental processes in nonlinear optics.It has a wide range of applications in our daily lives,including novel light sources,sensing,and information processing.It is usually assumed that nonlinear frequency conversion requires large crystals that gradually accumulate a strong effect.However,the large size of nonlinear crystals is not compatible with the miniaturisation of modern photonic and optoelectronic systems.Therefore,shrinking the nonlinear structures down to the nanoscale,while keeping favourable conversion efficiencies,is of great importance for future photonics applications.In the last decade,researchers have studied the strategies for enhancing the nonlinear efficiencies at the nanoscale,e.g.by employing different nonlinear materials,resonant couplings and hybridization techniques.In this paper,we provide a compact review of the nanomaterials-based efforts,ranging from metal to dielectric and semiconductor nanostructures,including their relevant nanofabrication techniques. 展开更多
关键词 NONLINEAR NANOPHOTONICS METALLIC NANOANTENNAS dielectric NANOANTENNAS III-V SEMICONDUCTOR nanoantenna nanofabrication
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The relaxin peptide family–potential future hope for neuroprotective therapy? A short review 被引量:1
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作者 Marius Nistor Martin Schmidt René Schiffner 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第3期402-405,共4页
Since its discovery in the 1920’s the relaxin peptide hormone family has not only grown in number to now seven members (relaxin-1, relaxin-2, relaxin-3, insulin-like peptide (INSL) 3, INSL4, INSL5 and INSL6), but... Since its discovery in the 1920’s the relaxin peptide hormone family has not only grown in number to now seven members (relaxin-1, relaxin-2, relaxin-3, insulin-like peptide (INSL) 3, INSL4, INSL5 and INSL6), but ever more effects, suchs as vasodilatory, angiogenic, anti-apoptopic, anti-fibriotic and anti-inflammatory, have been linked to them. While relaxin-2 has mainly been investigated in the context of cardiac protection, most comprehensively in the RELAX-AHF and RELAX AHF2 studies, a small number of studies have furthermore assessed the potential neuroprotective effects of especially relaxin-2 and other members of the relaxin family. In this short review we summarise and discuss recent efforts to utilize relaxin hormones for neuroprotection and point out potential future fields of research and translational applications. While many questions still need to be answered, the promising results of the available studies definitely warrant future well-designed studies on neuroprotection by relaxin peptides. 展开更多
关键词 RELAXIN relaxin-2 NEUROPROTECTION stroke hemorrhagic shock CEREBRAL
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Low-power emerging memristive designs towards secure hardware systems for applications in internet of things 被引量:2
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作者 Nan Du Heidemarie Schmidt Ilia Polian 《Nano Materials Science》 CAS CSCD 2021年第2期186-204,共19页
Emerging memristive devices offer enormous advantages for applications such as non-volatile memories and inmemory computing(IMC),but there is a rising interest in using memristive technologies for security application... Emerging memristive devices offer enormous advantages for applications such as non-volatile memories and inmemory computing(IMC),but there is a rising interest in using memristive technologies for security applications in the era of internet of things(IoT).In this review article,for achieving secure hardware systems in IoT,lowpower design techniques based on emerging memristive technology for hardware security primitives/systems are presented.By reviewing the state-of-the-art in three highlighted memristive application areas,i.e.memristive non-volatile memory,memristive reconfigurable logic computing and memristive artificial intelligent computing,their application-level impacts on the novel implementations of secret key generation,crypto functions and machine learning attacks are explored,respectively.For the low-power security applications in IoT,it is essential to understand how to best realize cryptographic circuitry using memristive circuitries,and to assess the implications of memristive crypto implementations on security and to develop novel computing paradigms that will enhance their security.This review article aims to help researchers to explore security solutions,to analyze new possible threats and to develop corresponding protections for the secure hardware systems based on low-cost memristive circuit designs. 展开更多
关键词 Memristive technology Nanoelectronic device Low-power consumption MINIATURIZATION Nonvolatility RECONFIGURABILITY In memory computing Artificial intelligence Hardware security primitives Machine learning-related attacks and defenses
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Sex differences in injury rates in team-sport athletes:A systematic review and meta-regression analysis 被引量:1
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作者 Astrid Zech Karsten Hollander +6 位作者 Astrid Junge Simon Steib Andreas Groll Jonas Heiner Florian Nowak Daniel P.feiffer Anna Lina Rahlf 《Journal of Sport and Health Science》 SCIE 2022年第1期104-114,共11页
Background:Team-sport players have a particularly high injury risk.Although female sex is considered a risk factor,it is still unknown whether female and male team-sport players,in fact,differ in their injury rates.We... Background:Team-sport players have a particularly high injury risk.Although female sex is considered a risk factor,it is still unknown whether female and male team-sport players,in fact,differ in their injury rates.We aimed to compare injury rates between female and male players by systematically reviewing and meta-analyzing injury surveillance studies of both sexes in order to evaluate sex-specific differences in team-sport injuries.Methods:Studies that prospectively collected injury data for high-level female and male players(age≥16 years)in basketball,field hockey,football(soccer),handball,rugby(union and sevens),and volleyball were included.Two reviewers(AZ and ALR)independently assessed study quality and extracted data for overall,match,training,and severe injuries(>28 days’time loss)as well as data regarding injury locations and types.Incidence rate ratios(IRRs)were pooled in a meta-analysis,and meta-regression analysis was performed when 10 or more studies were available.Results:Of 20 studies,9 studies reported injury data from football,3 studies from rugby,3 studies from handball,1 study from basketball,1 study from field hockey,2 studies from volleyball,and 1 study from basketball and field hockey.For overall injuries,the pooled IRR=0.86(95%confidence interval(95%CI):0.76-0.98)indicated significantly more injuries in male than in female players.For injury location,the pooled IRR showed higher injury rates in male athletes than in female athletes for upper extremity,hip/groin,thigh,ande foot injuries.Female players had a significantly higher rate of anterior cruciate ligament injuries(IRR=2.15,95%CI:1.27-3.62)than male players.No significant sex-specific differences in IRR were found for match,training,severe injuries,concussions,or ankle sprains.Conclusion:Our meta-analysis provides evidence for sex-specific differences in the injury rates in team sports.Further epidemiological studies including both sexes in sports other than football are needed in order to strengthen the evidence. 展开更多
关键词 ATHLETES FEMALE INJURIES MALE Team sports
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炎性乳癌和急性乳腺炎MR成像:对比研究 被引量:1
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作者 D.M. Renz P.A. Baltzer +4 位作者 J. Bottcher F. Thaher M. Gajda O. Camara 何健 《国际医学放射学杂志》 2009年第1期83-83,共1页
该研究目的是评估MR乳腺成像鉴别炎性乳癌和急性乳腺炎的潜力。该研究比较了2组经过选择的病人的MR乳腺成像检查:48例炎性乳癌和42例急性乳腺炎。2组之间在以下方面未显示显著性差异:肿块形态,非肿块样增强形态,乳腺增大,弥漫性皮... 该研究目的是评估MR乳腺成像鉴别炎性乳癌和急性乳腺炎的潜力。该研究比较了2组经过选择的病人的MR乳腺成像检查:48例炎性乳癌和42例急性乳腺炎。2组之间在以下方面未显示显著性差异:肿块形态,非肿块样增强形态,乳腺增大,弥漫性皮肤增厚,异常乳头外形,凸出的血管,皮肤/皮下的、乳头旁和弥漫性水肿。 展开更多
关键词 炎性乳癌 急性乳腺炎 乳腺感染 MR乳腺摄影 形态学 动力学
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Observation of a highly conductive warm dense state of water with ultrafast pump–probe freeelectron-laser measurements 被引量:1
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作者 Z.Chen X.Na +17 位作者 C.B.Curry S.Liang M.French A.Descamps D.P.DePonte J.D.Koralek J.B.Kim S.Lebovitz M.Nakatsutsumi B.K.Ofori-Okai R.Redmer C.Roedel M.Schörner S.Skruszewicz P.Sperling S.Toleikis M.Z.Mo S.H.Glenzer 《Matter and Radiation at Extremes》 SCIE CAS CSCD 2021年第5期1-12,共12页
The electrical conductivity of water under extreme temperatures and densities plays a central role in modeling planetary magnetic fields.Experimental data are vital to test theories of high-energy-densitywater and ass... The electrical conductivity of water under extreme temperatures and densities plays a central role in modeling planetary magnetic fields.Experimental data are vital to test theories of high-energy-densitywater and assess the possible development and presence of extraterrestrial life.These states are also important in biology and chemistry studies when specimens in water are confined and excited using ultrafast optical or free-electron lasers(FELs).Here we utilize femtosecond optical lasers to measure the transient reflection and transmission of ultrathin water sheet samples uniformly heated by a 13.6 nm FEL approaching a highly conducting state at electron temperatures exceeding 20000 K.The experiment probes the trajectory ofwater through the high-energy-density phase space and provides insights into changes in the index of refraction,charge carrier densities,andACelectrical conductivity at optical frequencies.At excitation energy densities exceeding 10MJ/kg,the index of refraction falls to n0.7,and the thermally excited free-carrier density reaches ne531027 m−3,which is over an order of magnitude higher than that of the electron carriers produced by direct photoionization.Significant specular reflection is observed owing to critical electron density shielding of electromagnetic waves.Themeasured optical conductivity reaches 23104 S/m,a value that is one to two orders of magnitude lower than those of simplemetals in a liquid state.At electron temperatures below 15000 K,the experimental results agreewell with the theoretical calculations using density-functional theory/molecular-dynamics simulations.With increasing temperature,the electron density increases and the system approaches a Fermi distribution.In this regime,the conductivities agree better with predictions from the Ziman theory of liquid metals. 展开更多
关键词 PUMP EXCEEDING state
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