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Levels of evidence and grades of recommendation supporting European society for medical oncology clinical practice guidelines
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作者 MARKO SKELIN BRUNA PERKOV-STIPIČIN +5 位作者 SANJA VUŠKOVIĆ MARINAŠANDRK PLEHAČEK ANE BAŠIĆ DAVIDŠARČEVIĆ MAJA ILIĆ IVAN KREČAK 《Oncology Research》 SCIE 2024年第5期807-815,共9页
Background:The European Society for Medical Oncology(ESMO)guidelines are among the most comprehensive and widely used clinical practice guidelines(CPGs)globally.However,the level of scientific evidence supporting ESMO... Background:The European Society for Medical Oncology(ESMO)guidelines are among the most comprehensive and widely used clinical practice guidelines(CPGs)globally.However,the level of scientific evidence supporting ESMO CPG recommendations has not been systematically investigated.This study assessed ESMO CPG levels of evidence(LOE)and grades of recommendations(GOR),as well as their trends over time across various cancer settings.Methods:We manually extracted every recommendation with the Infectious Diseases Society of America(IDSA)classification from each CPG.We examined the distribution of LOE and GOR in all available ESMO CPG guidelines across different topics and cancer types.Results:Among the 1,823 recommendations in the current CPG,30%were classified as LOEⅠ,and 43%were classified as GOR A.Overall,there was a slight decrease in LOEⅠ(−2%)and an increase in the proportion of GOR A(+1%)in the current CPG compared to previous versions.The proportion of GOR A recommendations based on higher levels of evidence such as randomized trials(LOEⅠ–Ⅱ)shows a decrease(71%vs.63%,p=0.009)while recommendations based on lower levels of evidence(LOEⅢ–Ⅴ)show an increase(29%vs.37%,p=0.01)between previous and current version.In the current versions,the highest proportion of LOEⅠ(42%)was found in recommendations related to pharmacotherapy,while the highest proportion of GOR A recommendations was found in the areas of pathology(50%)and diagnostic(50%)recommendations.Significant variability in LOEⅠand GOR A recommendations and their changes over time was observed across different cancer types.Conclusion:One-third of the current ESMO CPG recommendations are supported by the highest level of evidence.More well-designed randomized clinical trials are needed to increase the proportion of LOEⅠand GOR A recommendations,ultimately leading to improved outcomes for cancer patients. 展开更多
关键词 ESMO guidelines Clinical practice guidelines level of evidence Grade of recommendation
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Evaluation of the Effect of Four Levels of Shade on the Growth and Development of Desmodium adscendens with a View to Its Domestication as a Cover Crop in Côte d’Ivoire
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作者 Konan Didier Kouame Kouadio Jacques-Edouard Yao +3 位作者 Koffi Fernand Jean-Martial Kassi Kouadio Yann Henoc Kouadio Klinnanga Noël Kone Daouda Kone 《Agricultural Sciences》 2024年第11期1179-1194,共16页
Desmodium adscendens is a plant in the Fabaceae family that is very important to man, both agronomically and medicinally. It is an important cover crop that contributes to improving soil fertility, reducing the risks ... Desmodium adscendens is a plant in the Fabaceae family that is very important to man, both agronomically and medicinally. It is an important cover crop that contributes to improving soil fertility, reducing the risks associated with crop pests and weeds. However, very little research has been carried out into its domestication for use as a cover crop in banana plantations in Côte d’Ivoire. The general objective of this study was to evaluate, under semi-controlled conditions, the effect of different levels of shade on the growth and development of Desmodium adscendens. The studies were carried out on the experimental site of the UP-Plant Physiology Laboratory. Four shading levels were evaluated: 0 (NO), 20% (N1), 40% (N2) and 60% (N3) light levels. The Desmodium adscendens cuttings used were collected from a 3-month nursery. For each treatment, 10 tubs containing sterilized soil were used, and 50 cuttings were planted. After planting, growth and development parameters were assessed weekly on 10 plants. In addition, yield and fresh and dry mass were measured. Finally, the reproductive cycle of Desmodium adscendens was determined. The results showed that plant growth and development were greatest in plants grown under the 40% shade level, followed by the 20% and 60% shade levels. In contrast, plants in full light showed poor growth and development. The 40% shade level was the most favorable for growing Desmodium adscendens cuttings, with a cycle length of 67 days. Growing Desmodium adscendens under shade with 20% and 40% light levels could be recommended to farmers. 展开更多
关键词 Desmodium adscendens Shade levels Cover Crops Domestication—Côte d’Ivoire
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Three Levels of Friendship in Modern Chinese Culture
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作者 徐淑颖 《英语广场(学术研究)》 2013年第8期119-120,共2页
Friendship has been cherished by Chinese people for thousands of years. In the ancient times, a bosom friend is someone who is worth dying for. But its meaning has been changing as the society evolves. This essay disc... Friendship has been cherished by Chinese people for thousands of years. In the ancient times, a bosom friend is someone who is worth dying for. But its meaning has been changing as the society evolves. This essay discusses the three different levels of friendship in modern-day China. And by exemplifying these three types: acquaintances, companions and confidants, this essay aims at helping readers who are not familiar with modern Chinese culture to have a better understanding of the meaning of friendship in China. 展开更多
关键词 levelS FRIendsHIP Chinese Culture
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Transforming growth factor-β1 and vascular endothelial growth factor levels in senile acute myeloid leukemia and correlation with prognosis
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作者 Wan Li Sheng-Yu Ma Hui-Ying Zhao 《World Journal of Clinical Cases》 SCIE 2024年第20期4121-4129,共9页
BACKGROUND Acute myeloid leukemia(AML)is a disease in which immature hematopoietic cells accumulate in the bone marrow and continuously expand,inhibiting hematopoiesis.The treatment and prognosis of this disease have ... BACKGROUND Acute myeloid leukemia(AML)is a disease in which immature hematopoietic cells accumulate in the bone marrow and continuously expand,inhibiting hematopoiesis.The treatment and prognosis of this disease have always been unsatisfactory.AIM To investigate the correlation between vascular endothelial growth factor(VEGF)and transforming growth factor-β1(TGFβ1)expression and prognosis in older adults with AML.METHODS This study enrolled 80 patients with AML(AML group),including 36 with complete response(AML-CR),23 with partial response(AML-PR),and 21 with no response(AML-NR).The expression levels of VEGF and TGFβ1 were detected by reverse transcription polymerase chain reaction in bone marrow mononuclear cells isolated from 56 healthy controls.Kaplan-Meier analysis was performed to assess overall survival(OS)and progression-or disease-free survival(DFS).Prognostic risk factors were analyzed using a Cox proportional hazards model.RESULTS The AML group showed a VEGF level of 2.68±0.16.VEGF expression was lower in patients with AML-CR than those with AML-PR or AML-NR(P<0.05).TGFβ1 expression in the AML group was 0.33±0.05.Patients with AML-CR showed a higher TGFβ1 expression than those with AML-PR or AML-NR(P<0.05).VEGF and TGFβ1 expression in patients with AML was significantly correlated with the counts of leukocytes,platelets,hemoglobin,and peripheral blood immature cells(P<0.05);Kaplan-Meier survival analysis revealed that patients with high TGFβ1 expression had better OS and DFS than those with low TGFβ1 expression(P<0.05),whereas patients with low VEGF levels showed better OS and DFS than those with high VEGF levels(P<0.05).VEGF,TGFβ1,and platelet count were identified by the Cox proportional hazards model as independent risk factors for OS(P<0.05),while VEGF,TGFβ1,and white blood cell count were independent risk factors for DFS(P<0.05).CONCLUSION Decreased VEGF expression and increased TGFβ1 expression in patients with AML provide valuable references for determining and individualizing clinical treatment strategies. 展开更多
关键词 Acute myeloid leukemia Transforming growth factor-β1 Vascular endothelial growth factor Expression level Prognostic correlation
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Groundwater level thresholds for maintaining groundwater-dependent ecosystems in northwest China:Current developments and future challenges
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作者 Ming-yang Li Chao-zhu Li +2 位作者 Feng Dong Peng Jiang Yong-qiang Li 《Journal of Groundwater Science and Engineering》 2024年第4期453-462,共10页
Groundwater-Dependent Ecosystems(GDEs)in the arid region of northwest China are crucial for maintaining ecological balance and biodiversity.However,the ongoing decline in groundwater levels caused by excessive groundw... Groundwater-Dependent Ecosystems(GDEs)in the arid region of northwest China are crucial for maintaining ecological balance and biodiversity.However,the ongoing decline in groundwater levels caused by excessive groundwater exploitation poses a potential threat to GDEs.This paper reviews the current developments and future challenges associated with defining groundwater level thresholds for maintaining GDEs in arid regions.It focuses on methods for identifying and investigating these thresholds,with particular attention to recent advances in northwest China.Additionally,this paper highlights the limitations and future challenges in determining these thresholds,including the complexities of ecological processes,groundwater systems,data availability,and methodological constraints.To address these issues,a multidisciplinary approach that incorporates new technologies,such as multi-source data fusion,machine learning models,and big data and cloud computing,will be essential.By overcoming these challenges and utilizing effective methods,appropriate groundwater level thresholds can be established to ensure the longterm sustainability of GDEs. 展开更多
关键词 Arid region VEGETATION Groundwater level threshold Depth to water table Groundwaterdependent ecosystems(GDEs)
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Estimating trends of the Mediterranean Sea level changes from tide gauge and satellite altimetry data (1993-2015)
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作者 TAIBI Hebib HADDAD Mahdi 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第4期1176-1185,共10页
The impact of climate change on sea level has received a great deal of attention by scientists worldwide. In this context, the problem of sea levels on global and regional scales have been analyzed in a number of stud... The impact of climate change on sea level has received a great deal of attention by scientists worldwide. In this context, the problem of sea levels on global and regional scales have been analyzed in a number of studies based on tide gauges observations and satellite altimetry measurements. This study focuses on trend estimates from 18 high-quality tide gauge stations along the Mediterranean Sea coast. The seasonal Mann-Kendall test was run at a 5% significance level for each of the 18 stations for the period of 1993-2015 (satellite altimetry era). The results of this test indicate that the trends for 17 stations were statistically significant and showed an increase (no significant trend was observed only at one station). The rates of sea level change for the 17 stations that exhibit significant trends, estimated using seasonal Sen's approach, range after correction for Vertical Land Motion (VLM) from 1.48 to 8.72 mm/a for the period 1993-2015. Furthermore, the magnitude of change at the location of each tide gauge station was estimated using the satellite altimetry measurements. Thus, the results obtained agree with those from the tide-gauge data analysis. 展开更多
关键词 sea level TIDAL height SATELLITE ALTIMETRY TRend analysis MANN-KendALL test Sen's slope ESTIMATES
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Mediterranean Sea level trends from long-period tide gauge time series
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作者 Haddad Mahdi Taibi Hebib 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第1期157-165,共9页
The main purpose of this study is to highlight, on the basis of statistical tests, the significant long-term changes of the Mediterranean Sea level, through the analysis of historical tide gauge records. In this frame... The main purpose of this study is to highlight, on the basis of statistical tests, the significant long-term changes of the Mediterranean Sea level, through the analysis of historical tide gauge records. In this framework, 14 tide gauge monthly series selected from the Permanent Service of the Mean Sea Level(PSMSL) database were used. The search for the presence or not of trends within these series, that have a temporal coverage from 59 to 142 years, was carried out using the Mann-Kendall test and the Sen’s slope estimator. The obtained results show that the Split Rt Marjana series are the only ones which does not exhibit a significant trend. The other 13 series show significant increasing trends. This result seems sufficient to suppose the presence, in the past century, of a new climatic phase on the scale of the Mediterranean basin, where the rising sea level is one of the consequences. 展开更多
关键词 sea level tidal heights trend analysis Mann-Kendall test Sen’s slope estimates
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Nomogram for overall survival in ampullary adenocarcinoma using the surveillance,epidemiology,and end results database and external validation
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作者 Jia Yang Zi-Yi Wang +2 位作者 Jing Chen Yao Zhang Lei Chen 《World Journal of Clinical Oncology》 2025年第2期36-51,共16页
BACKGROUND Ampullary adenocarcinoma is a rare malignant tumor of the gastrointestinal tract.Currently,only a few cases have been reported,resulting in limited information on survival.AIM To develop a dynamic nomogram ... BACKGROUND Ampullary adenocarcinoma is a rare malignant tumor of the gastrointestinal tract.Currently,only a few cases have been reported,resulting in limited information on survival.AIM To develop a dynamic nomogram using internal and external validation to predict survival in patients with ampullary adenocarcinoma.METHODS Data were sourced from the surveillance,epidemiology,and end results stat database.The patients in the database were randomized in a 7:3 ratio into training and validation groups.Using Cox regression univariate and multivariate analyses in the training group,we identified independent risk factors for overall survival and cancer-specific survival to develop the nomogram.The nomogram was validated with a cohort of patients from the First Affiliated Hospital of the Army Medical University.RESULTS For overall and cancer-specific survival,12(sex,age,race,lymph node ratio,tumor size,chemotherapy,surgical modality,T stage,tumor differentiation,brain metastasis,lung metastasis,and extension)and 6(age;surveillance,epidemiology,and end results stage;lymph node ratio;chemotherapy;surgical modality;and tumor differentiation)independent risk factors,respectively,were incorporated into the nomogram.The area under the curve values at 1,3,and 5 years,respectively,were 0.807,0.842,and 0.826 for overall survival and 0.816,0.835,and 0.841 for cancer-specific survival.The internal and external validation cohorts indicated good consistency of the nomogram.CONCLUSION The dynamic nomogram offers robust predictive efficacy for the overall and cancer-specific survival of ampullary adenocarcinoma. 展开更多
关键词 Ampullary adenocarcinoma Dynamic nomogram Gastrointestinal tract SURVEILLANCE EPIDEMIOLOGY end results database Survival rate
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融合Dead-ends和离线监督Actor-Critic的动态治疗策略生成模型
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作者 杨莎莎 于亚新 +3 位作者 王跃茹 许晶铭 魏阳杰 李新华 《计算机科学》 CSCD 北大核心 2024年第7期80-88,共9页
强化学习对数学模型依赖性低,利用经验便于架构和优化模型,非常适合用于动态治疗策略学习。但现有研究仍存在以下问题:1)学习策略最优性的同时未考虑风险,导致学到的策略存在一定的风险;2)忽略了分布偏移问题,导致学到的策略与医生策略... 强化学习对数学模型依赖性低,利用经验便于架构和优化模型,非常适合用于动态治疗策略学习。但现有研究仍存在以下问题:1)学习策略最优性的同时未考虑风险,导致学到的策略存在一定的风险;2)忽略了分布偏移问题,导致学到的策略与医生策略完全不同;3)忽略患者的历史观测数据和治疗史,从而不能很好地得到患者状态,进而导致不能学到最优策略。基于此,提出了融合Dead-ends和离线监督Actor-Critic的动态治疗策略生成模型DOSAC-DTR。首先,考虑学到的策略所推荐的治疗行动的风险性,在Actor-Critic框架中融入Dead-ends概念;其次,为缓解分布偏移问题,在Actor-Critic框架中融入医生监督,在最大化预期回报的同时,最小化所学策略与医生策略之间的差距;最后,为了得到包含患者关键历史信息的状态表示,使用基于LSTM的编码器解码器模型对患者的历史观测数据和治疗史进行建模。实验结果表明,DOSAC-DTR相比基线方法有更好的性能,可以得到更低的估计死亡率以及更高的Jaccard系数。 展开更多
关键词 动态治疗策略 Dead-ends Actor-Critic 状态表征
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Booster for achieving the sustainable development agenda——Chinese social organizations attends the 2018 UN High-level Political Forum on Sustainable Development
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作者 Bian Peilin(Translated) 《International Understanding》 2018年第3期44-46,共3页
On July 9,the 2018 United Nations High Level Political Forum on Sustainable Development was grandly opened at the United Nations Headquarters in New York.China NGO Network for International Exchanges (CNIE)organized a... On July 9,the 2018 United Nations High Level Political Forum on Sustainable Development was grandly opened at the United Nations Headquarters in New York.China NGO Network for International Exchanges (CNIE)organized a number of social organizations in China to attend the forum,held a theme seminar,and participated in the photo exhibition of the forum. 展开更多
关键词 UNITED Nations High level POLITICAL FORUM
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On the Problem of All Equal Positive Odd Number Solutions of the Dissemination of the Ends' Guess 被引量:1
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作者 刘元宗 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第2期108-109,共2页
The thesis is concerned with the problem of the dissemination of the Ends’ guess and offers the formula of all equal positive odd number solutions.
关键词 ends guess DISSEMINATION all equal positive odd number solutions
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Combination of two-hour post-endoscopic retrograde cholangiopancreatography amylase levels and cannulation times is useful for predicting post-endoscopic retrograde cholangiopancreatography pancreatitis 被引量:5
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作者 Shiro Hayashi Tsutomu Nishida +10 位作者 Hiromi Shimakoshi Akiyoshi Shimoda Takahiro Amano Aya Sugimoto Kei Takahashi Kaori Mukai Tokuhiro Matsubara Masashi Yamamoto Sachiko Nakajima Koji Fukui Masami Inada 《World Journal of Gastrointestinal Endoscopy》 CAS 2016年第20期777-784,共8页
AIM To estimate the efficacy of 2 h post-endoscopic retrograde cholangiopancreatography(ERCP) serum amylase levels and other factors for predicting postERCP pancreatitis.METHODS This was a retrospective,single-center ... AIM To estimate the efficacy of 2 h post-endoscopic retrograde cholangiopancreatography(ERCP) serum amylase levels and other factors for predicting postERCP pancreatitis.METHODS This was a retrospective,single-center cohort study of consecutive patients who underwent ERCP from January 2010 to December 2013.Serum amylase levels were measured 2 h post-procedure,and patient- and procedure-related pancreatitis(PEP) risk factors wereanalyzed using a logistic model.RESULTS A total of 1520 cases(average age 72 ± 12 years,60% male) were initially enrolled in this study,and 1403 cases(725 patients) were ultimately analyzed after the exclusion of 117 cases.Fifty-five of these cases developed PEP.We established a 2 h serum amylase cutoff level of two times the upper limit of normal for predicting PEP.Multivariate analysis revealed that a cannulation time of more than 13 min [odds ratio(OR) 2.28,95%CI:1.132-4.651,P=0.0210] and 2 h amylase levels greater than the cutoff level(OR=24.1,95%CI:11.56-57.13,P<0.0001) were significant predictive factors for PEP.Forty-seven of the 55 patients who developed PEP exhibited 2 h amylase levels greater than the cutoff level(85%),and six of the remaining eight patients who developed PEP(75%) required longer cannulation times.Only 2 of the 1403 patients(0.14%) who developed PEP did not exhibit concerning 2 h amylase levels or require longer cannulation times.CONCLUSION These findings indicate that the combination of 2 h post-ERCP serum amylase levels and cannulation times represents a valuable marker for identifying patients at high risk for PEP. 展开更多
关键词 Serum AMYLASE levelS CANNULATION time Post-endoscopic retrograde CHOLANGIOPANCREATOGRAPHY PANCREATITIS Predictor
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Hybrid Level of Detail Algorithm for Real-Time Rendering of Large-Scale Terrain 被引量:1
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作者 杜剑侠 李凤霞 战守义 《Journal of Beijing Institute of Technology》 EI CAS 2006年第4期416-419,共4页
Hybrid level of detail (LOD) (HLOD) algorithm based on discrete LOD and continuous LOD is presented for real-time rendering of large-scale terrains. There are n HLOD models created off-line, which form a pyramid w... Hybrid level of detail (LOD) (HLOD) algorithm based on discrete LOD and continuous LOD is presented for real-time rendering of large-scale terrains. There are n HLOD models created off-line, which form a pyramid with n layers. Each of these models contains countless versions of the model at various levels of detail. When rendering, the corresponding models in some layer will be chosen. As the viewer's moves, either the continuous LOD algorithm will be applied to the selected models, or the visible models in another layer will be selected. An experiment on a triangular irregular network(TIN) terrain model was performed respectively using discrete LOD, continuous LOD and HLOD. The experimental results show that the HLOD algorithm exceeds the other two kinds of LOD in frame rate without reduction of terrain's fidelity. 展开更多
关键词 hybrid level of detail (HLOD) discrete level of detail continuous level of detail level of detail control
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Large magnetic moment at sheared ends of single-walled carbon nanotubes 被引量:1
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作者 Jian Zhang Ya Deng +12 位作者 Ting-Ting Hao Xiao Hu Ya-Yun Liu Zhi-Sheng Peng Xian-Nian Chi Pei Wu Si-Yu Liu Zhong Zhang Jun-Jie Li Gong-Tang Wang Wei-Guo Chu Chang-Zhi Gu Lian-Feng Sun 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第12期510-516,共7页
In this work we report that after single-walled carbon nanotubes(SWNTs) are sheared with a pair of titanium scissors,the magnetization becomes larger than that of the corresponding pristine ones. The magnetization inc... In this work we report that after single-walled carbon nanotubes(SWNTs) are sheared with a pair of titanium scissors,the magnetization becomes larger than that of the corresponding pristine ones. The magnetization increases proportionally with the number of SWNTs with sheared ends, suggesting that there exist magnetic moments at the sheared ends of SWNTs.By using the coefficient of this linear relation, the average magnetic moment is estimated to be 41.5 ± 9.8 μB(Bohr magneton) per carbon atom in the edge state at temperature of 300.0 K, suggesting that ultrahigh magnetic fields can be produced. The dangling sigma and pi bonds of the carbon atoms at sheared ends play important roles in determining the unexpectedly high magnetic moments, which may have great potential applications. 展开更多
关键词 carbon nanotubes SHEAR open ends magnetic moments
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Endogenous Levels of Polyamines under Water-Deficit Stress during Cotton’s Reproductive Development 被引量:3
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作者 Dimitra A. Loka Derrick M. Oosterhuis Cristiane Pilon 《American Journal of Plant Sciences》 2015年第2期344-354,共11页
Polyamines, putrescine (PUT), spermidine (SPD) and spermine (SPM) are implicated in plants’ responses under conditions of abiotic stress. Previous research in other crops has indicated that polyamines and changes in ... Polyamines, putrescine (PUT), spermidine (SPD) and spermine (SPM) are implicated in plants’ responses under conditions of abiotic stress. Previous research in other crops has indicated that polyamines and changes in their concentrations are associated with drought tolerance under conditions of water-deficit stress;however, no information exists on cotton (Gossypium hirsutum L.). Growth chamber experiments were conducted with two cotton cultivars differing in drought tolerance, ST5288B2F (drought-sensitive) and Siokra L23 (drought-tolerant) in order to investigate the distribution of free polyamines, the effect of water-deficit stress on the polyamine metabolism of cotton reproductive units and their subtending leaves as well as the possible relationship between polyamines and drought tolerance in cotton. Our results showed that cotton ovaries contained significantly higher levels of total free polyamines compared to their subtending leaves under both control and water stress conditions. Water-deficit stress significantly increased PUT concentrations in ST5288B2F, while SPM levels significantly decreased in Siokra L23. The results indicated that water-deficit stress significantly affected cotton polyamine metabolism in reproductive structures and their subtending leaves;however, no clear relationship between drought-tolerance and changes in polyamine accumulation was established. Further research is needed to elucidate the mechanism according to which water-deficit stress affects polyamine metabolism. 展开更多
关键词 COTTON Gas Exchange POLYAMINE levelS REPRODUCTIVE Units WATER-DEFICIT Stress
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Hydro-Meteorological Trends in Southwest Coastal Bangladesh: Perspectives of Climate Change and Human Interventions 被引量:5
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作者 M. Shahjahan Mondal Mohammad Rashed Jalal +3 位作者 M. Shah Alam Khan Uthpal Kumar Rezaur Rahman Hamidul Huq 《American Journal of Climate Change》 2013年第1期62-70,共9页
The southwest coastal region of Bangladesh, being under tidal influence and dependent on sweet water supplies from upstream, has a unique brackish water ecosystem. The region, having vast low-lying areas enclosed by m... The southwest coastal region of Bangladesh, being under tidal influence and dependent on sweet water supplies from upstream, has a unique brackish water ecosystem. The region, having vast low-lying areas enclosed by man-made polders, is considered to be highly vulnerable to climate change induced hazards. In this study, linear trends in hydro-climatic variables, such as temperature, rainfall, sunshine, humidity, sweet water inflow and tidal water level in the region are assessed using secondary data and following both parametric and nonparametric statistical techniques. Correlation between the sweet water flow from the Gorai River, a major distributary of the Ganges River, and the salinity level in the Rupsa-Pasur River near Khulna, a southern metropolis, is also investigated. The results reveal that the temperature in the Khulna region is increasing at a significant rate, particularly in recent years. The number of extremely cold nights is decreasing and the heat index is increasing. The sunshine duration has a decreasing trend and the humidity has an increasing trend. Rainfall is increasing in terms of both magnitude and number of rainy days. However, the annual maximum rainfall and the number of days with high intensity rainfall have remained almost static. The annual maximum tidal high water level is increasing and the annual minimum low water level is decreasing at a rate of 7 - 18 mm and 4 - 8 mm per year, respectively. There is a negative correlation between the Gorai flow and the river water salinity around Khulna. Dredging of the Gorai during 1998-2001 resulted in an improvement of the salinity situation in the Khulna region. The variation in water salinity, tidal water level and sweet water flows in different time periods indicates that the human interventions through upstream diversion and coastal polders have contributed more in hydro-morphological changes in the southwest than the climate change. However, there are some evidences of climate change in the meteorological variables at Khulna. 展开更多
关键词 Trend Hydro-Meteorology SOUTHWEST Coastal BANGLADESH Salinity TIDAL Water level Human Interventions
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Giant magnetic moment at open ends of multiwalled carbon nanotubes 被引量:1
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作者 王钢 陈闽江 +10 位作者 余芳 薛磊江 邓娅 张键 齐笑迎 高燕 褚卫国 刘广同 杨海方 顾长志 孙连峰 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第1期418-422,共5页
The attractions of cantilevers made of multiwalled carbon nanotubes(MWNTs) and secured on one end are studied in the non-uniform magnetic field of a permanent magnet. Under an optical microscope, the positions and t... The attractions of cantilevers made of multiwalled carbon nanotubes(MWNTs) and secured on one end are studied in the non-uniform magnetic field of a permanent magnet. Under an optical microscope, the positions and the corresponding deflections of the original cantilevers(with iron catalytic nanoparticles at the free end) and corresponding cut-off cantilevers(the free ends consisting of open ends of MWNTs) are studied. Both kinds of CNT cantilevers are found to be attracted by the magnet, and the point of application of force is proven to be at the tip of the cantilever. By measuring and comparing deflections between these two kinds of cantilevers, the magnetic moment at the open ends of the CNTs can be quantified.Due to the unexpectedly high value of the magnetic moment at the open ends of carbon nanotubes, it is called giant magnetic moment, and its possible mechanisms are proposed and discussed. 展开更多
关键词 carbon nanotubes open ends giant magnetic moment
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Endozepine-4 levels are increased in hepatic coma 被引量:2
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作者 Giulia Malaguarnera Marco Vacante +4 位作者 Filippo Drago Gaetano Bertino Massimo Motta Maria Giordano Michele Malaguarnera 《World Journal of Gastroenterology》 SCIE CAS 2015年第30期9103-9110,共8页
AIM:To evaluate the serum levels of endozepine-4,their relation with ammonia serum levels,the grading of coma and the severity of cirrhosis,in patients with hepatic coma. METHODS:In this study we included 20 subjects ... AIM:To evaluate the serum levels of endozepine-4,their relation with ammonia serum levels,the grading of coma and the severity of cirrhosis,in patients with hepatic coma. METHODS:In this study we included 20 subjects with Hepatic coma,20 subjects with minimal hepatic encephalopathy(MHE) and 20 subjects control. All subjects underwent blood analysis,Child Pugh and Model for End- stage liver disease(MELD) assessment,endozepine-4 analysis. RESULTS:Subjects with hepatic coma showed significant difference in endozepine-4(P < 0.001) and NH3 levels(P < 0.001) compared both to MHE and controls patients. Between NH3 and endozepine-4 we observed a significant correlation(P = 0.009; Pearson correlation 0.570). There was a significant correlation between endozepine-4 and MELD(P = 0.017; Pearsoncorrelation = 0.529). In our study blood ammonia concentration was noted to be raised in patients with hepatic coma,with the highest ammonia levels being found in those who were comatose. We also found a high correlation between endozepine-4 and ammonia(P < 0.001). In patients with grade Ⅳ hepatic coma,endozepine levels were significantly higher compared to other groups. CONCLUSION:This study suggests that an increased level of endozepine in subjects with higher levels of MELD was observed. In conclusion,data concerning involvement of the GABA-ergic system in HE coma could be explained by stage-specific alterations. 展开更多
关键词 endozepine-4 HEPATIC ENCEPHALOPATHY HEPATIC COMA Cirrhosis BENZODIAZEPINE Peripheralbenzodiazepine receptor Model for end - stage liverdisease Glutamate-related NEUROTOXICITY which in turnmay alter the γ-aminobutyric acid
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A study of sea level variability and its long-term trend in the South China Sea 被引量:1
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作者 XU Ying LIN Mingsen +2 位作者 ZHENG Quan'an SONG Qingtao YE Xiaomin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第9期22-33,共12页
On the basis of the satellite maps of sea level anomaly(MSLA) data and in situ tidal gauge sea level data,correlation analysis and empirical mode decomposition(EMD) are employed to investigate the applicability of... On the basis of the satellite maps of sea level anomaly(MSLA) data and in situ tidal gauge sea level data,correlation analysis and empirical mode decomposition(EMD) are employed to investigate the applicability of MSLA data,sea level correlation,long-term sea level variability(SLV) trend,sea level rise(SLR) rate and its geographic distribution in the South China Sea(SCS).The findings show that for Dongfang Station,Haikou Station,Shanwei Station and Zhapo Station,the minimum correlation coefficient between the closest MSLA grid point and tidal station is 0.61.This suggests that the satellite altimeter MSLA data are effective to observe the coastal SLV in the SCS.On the monthly scale,coastal SLV in the western and northern part of SCS are highly associated with coastal currents.On the seasonal scale,SLV of the coastal area in the western part of the SCS is still strongly influenced by the coastal current system in summer and winter.The Pacific change can affect the SCS mainly in winter rather than summer and the affected area mostly concentrated in the northeastern and eastern parts of the SCS.Overall,the average SLR in the SCS is 90.8 mm with a rising rate of(5.0±0.4) mm/a during1993–2010.The SLR rate from the southern Luzon Strait through the Huangyan Seamount area to the Xisha Islands area is higher than that of other areas of the SCS. 展开更多
关键词 South China Sea sea level variability correlation analysis empirical mode decomposition
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Blood oxygen level–dependent functional magnetic resonance imaging can evaluate the efficiency of transcatheter arterial chemoembolization in hepatocellular carcinoma 被引量:2
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作者 Lizhi Xiao Enhua Xiao 《Journal of Interventional Medicine》 2019年第1期5-7,共3页
Hepatocellular carcinoma(HCC) is among the most common malignant tumors worldwide, and transcatheter arterial chemoembolization(TACE) technology has become the first-line treatment for advanced HCC. Another important,... Hepatocellular carcinoma(HCC) is among the most common malignant tumors worldwide, and transcatheter arterial chemoembolization(TACE) technology has become the first-line treatment for advanced HCC. Another important, recently developed technique is blood oxygen level–dependent functional magnetic resonance imaging(BOLD-fMRI), which utilizes hemoglobin as an endogenous contrast agent and measures deoxygenated hemoglobin content by sampling the oxygen content of tissues, thus reflecting the hemodynamics and pathophysiologic changes in body organs. Currently this technology is being used in patients with liver tumors;that is, it serves as an important tool in follow-up after TACE. The present paper summarizes these developments. 展开更多
关键词 Blood oxygen level–dependent Magnetic resonance imaging EFFICIENCY HEPATOCELLULAR carcinoma TRANSCATHETER arterial CHEMOEMBOLIZATION
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