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Analysis of the causes of primary revision after unicompartmental knee arthroplasty: A case series 被引量:3
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作者 Jin-Long Zhao Xiao Jin +5 位作者 He-Tao Huang Wei-Yi Yang Jia-Hui Li Ming-Hui Luo Jun Liu Jian-Ke Pan 《World Journal of Clinical Cases》 SCIE 2024年第9期1560-1568,共9页
BACKGROUND Unicompartmental knee arthroplasty(UKA)has great advantages in the treatment of unicompartmental knee osteoarthritis,but its revision rate is higher than that of total knee arthroplasty.AIM To summarize and... BACKGROUND Unicompartmental knee arthroplasty(UKA)has great advantages in the treatment of unicompartmental knee osteoarthritis,but its revision rate is higher than that of total knee arthroplasty.AIM To summarize and analyse the causes of revision after UKA.METHODS This is a retrospective case series study in which the reasons for the first revision after UKA are summarized.We analysed the clinical symptoms,medical histories,laboratory test results,imaging examination results and treatment processes of the patients who underwent revision and summarized the reasons for primary revision after UKA.RESULTS A total of 13 patients,including 3 males and 10 females,underwent revision surgery after UKA.The average age of the included patients was 67.62 years.The prosthesis was used for 3 d to 72 months.The main reasons for revision after UKA were improper suturing of the surgical opening(1 patient),osteophytes(2 patients),intra-articular loose bodies(2 patients),tibial prosthesis loosening(2 patients),rheumatoid arthritis(1 patient),gasket dislocation(3 patients),anterior cruciate ligament injury(1 patient),and medial collateral ligament injury with residual bone cement(1 patient).CONCLUSION The causes of primary revision after UKA were gasket dislocation,osteophytes,intra-articular loose bodies and tibial prosthesis loosening.Avoidance of these factors may greatly reduce the rate of revision after UKA,improve patient satisfaction and reduce medical burden. 展开更多
关键词 Unicompartmental knee arthroplasty Total knee arthroplasty causeS REVISION Case series
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Analysis of Claims in the Uganda Construction Industry
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作者 Alinaitwe Henry 《Journal of Civil Engineering and Architecture》 2025年第1期36-43,共8页
The increasing cost of infrastructure development risks stifling national investment plans.Many projects in Uganda have suffered because of the frequency and magnitude of claims made by parties involved especially the... The increasing cost of infrastructure development risks stifling national investment plans.Many projects in Uganda have suffered because of the frequency and magnitude of claims made by parties involved especially the contractors.As a result,the construction industry is plagued with claims which quite often lead to adversarial relationships.The major grounds for claims were identified through studying the contract documents where claims had been made.Increase in scope;change orders;errors in contract documents;inclement weather;inflation;delay in possessing the site;and change in the tax policy were the most prevalent grounds for making claims.Problems identified in claiming process include delays in getting approval;information on claims not reliable;hostility from the parties involved;pricing of claims;delays in effecting payment when approved;and overzealous contract interpretation leading to misunderstanding and delays Using a survey on project managers for 64 contractors and their corresponding clients or their representatives,the major ways in which it can be reduced were identified as being thoroughness during the design phase;providing for inflation;proper planning of works;using prequalified contractors;and proper documentation of records.Clients have a big role to play in reducing claims. 展开更多
关键词 CLAIMS CONSTRUCTION causeS disputes
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The third dimension of alpine plant leaf traits is related to cold-tolerance
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作者 Yuan Wang Ji Suonan +4 位作者 Kun Liu Yanni Gao Sihao Zhu Qian Liu Ning Zhao 《Plant Diversity》 2025年第1期159-165,共7页
Alpine plants possess unique traits to adapt alpine environments.Whether leaf trait relationships of alpine plants can be captured by the two trait dimensions of organ size and resource economics is unknown.We hypothe... Alpine plants possess unique traits to adapt alpine environments.Whether leaf trait relationships of alpine plants can be captured by the two trait dimensions of organ size and resource economics is unknown.We hypothesized that,beyond the trait dimensions of leaf size and resource economics,nonstructured carbohydrates(NSC)would reflect a dimension of cold-tolerance in alpine plants.To test this hypothesis,we measured 12 leaf traits critical to leaf construction and growth in 143 species across 7 sites ranging from alpine steppes to alpine meadows along an environmental gradient on the Tibetan Plateau.Furthermore,a cold resistance experiment was conducted at one of these sites to estimate the lethal temperature causing 50%frost damage(LT_(50))of 11 alpine species.The majority of variations in 12 leaf traits of alpine plants were captured by three trait axes,in which leaf carbon(LCC)and NSC(including leaf starch;LSC and leaf soluble sugars;LSS)were clustered in a new dimension(PC3)beyond leaf size and structure,and resource economics.Although LCC,LSC and LSS all showed negative correlations with mean annual temperature,a significant negative correlation was only found between LSS and LT_(50).It indicated that PC3 was able to reflect the cold-tolerance of alpine plants to some extent,in which LSS was the most critical trait.The storage and transformation of NSC under stressful conditions could reflect a dimension of long-term metabolic adaptation and cold-tolerance,which is an extension of the resource-utilization strategy beyond construction cost and growth. 展开更多
关键词 Non-structured carbohydrates Resource economics Stress resistance Trait relationships the lethal temperature causing 50%frost damage(LT50)
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The Impacts and Causes of Land Fragmentation on Farm Productivity: Case Review of East African Countries
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作者 Joseph Mayindo Mayele Jacob B. Kolleh Joel Emmanuel Saburi 《Open Journal of Ecology》 2024年第5期455-482,共28页
This report provides an overall assessment of land fragmentation problems in East Africa. Many parts of East Africa have become highly fragmented, putting development systems and activities in these areas at risk of c... This report provides an overall assessment of land fragmentation problems in East Africa. Many parts of East Africa have become highly fragmented, putting development systems and activities in these areas at risk of complete collapse. Land fragmentation occurs when land gets converted for agriculture, industrialization, or urbanization, invaded by non-local plants, or enclosed for individual use and by subdividing farmlands into subsequent smaller units called parcels with varying average farm sizes. Fragmentation results from inappropriate agricultural development processes and ineffective land use planning that fails to recognize how farmland is used, and the importance of its interconnected areas. Insecurity of tenure and resource rights are key factors in making this possible. Land fragmentation is one of the key reasons why the ability of most resources in East Africa becomes scarcer, and those remaining become “privatized” by more powerful community members—keen to maintain their access to them. Such individualistic attitudes are new and disadvantage the poorest even further by affecting the traditional customary safety nets and agricultural outputs. Neither the government nor customary governance systems effectively protect resource access for the poorest. This review summary report identifies the key causes, measures, and implications, government interventions, and the common remedies to land fragmentation problems in the East African Countries of Kenya, Uganda, Rwanda, and Tanzania including neighboring Ethiopia, and the Sudan. The findings indicated from 2005 to 2015, the population kept increasing for all the named countries in East Africa with Rwanda and Uganda having a substantial increase in population density. The study review further explores the trend in the performance of agriculture by average farm sizes within the intervals of five years by highlighting their strong linkages and found that the average farm size has declined drastically, especially for Kenya. This can only mean that small farms kept becoming smaller and smaller and that there were more small-scale farmers. The results further depicted that the major and commonly cultivated food crops among the East African countries include maize, sorghum, rice, cassava, sweet potatoes, bananas, Irish potatoes, beans, peas, etc., with maize yields (Mt/ha) in 2003 for Uganda being the highest (1.79 Mt/ha) and the lowest in Rwanda (0.77 Mt/ha) respectively. Therefore, from the review results, recommendations are being made as to how the negative impacts of land fragmentation on agricultural productivity can be reduced or mitigated. One way is by community sensitization and awareness about the importance of land consolidation and its proposition on farm productivity. 展开更多
关键词 Land Fragmentation Land Consolidation Farm Productivity INDUSTRIALIZATION Impacts causeS Average Farm Size Population East Africa
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Eternal Climate Change Patterns and the Causes and Countermeasures of Global Climate Change
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作者 Cuixiang Zhong 《Journal of Environmental Science and Engineering(B)》 2024年第1期9-20,共12页
It is an objective fact that the weather is unpredictable.Even the famous meteorologist,Academician Chu Ko Chen,has only a partial understanding of the changing laws of wind and rain.Even though ancient people summari... It is an objective fact that the weather is unpredictable.Even the famous meteorologist,Academician Chu Ko Chen,has only a partial understanding of the changing laws of wind and rain.Even though ancient people summarized the 24 solar terms by observing the annual activities of the sun for a long time,because they ignored the impact of the activities of the moon on the Earth’s climate change on a small scale,the 24 solar terms they summarized often could not accurately predict the change of the Earth’s climate.Therefore,the author studied the influence of lunar activities on the Earth’s climate change,finds out the law of the influence of lunar activities on the Earth’s climate change on a small scale,and summarizes the eternal climate change pattern determined by the activities of the sun and the moon.In addition,the author also reveals the causes and countermeasures of global warming and the frequent occurrence of extreme weather as well as environmental change. 展开更多
关键词 Eternal climate change patterns global warming extreme weather abrupt environmental changes causeS countermeasures.
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Analysis of the Factors That Cause Environmental Degradation of Lake Santa Maria Tasi Tolu Dili Timor-Leste
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作者 Antero Freitas Branco 《Journal of Geoscience and Environment Protection》 2024年第10期55-67,共13页
This research aims to understand more closely the damage to the lake environment and the factors that cause pollution in Lake Santa Maria are the first factor of increasing urbanization, the use of the land around the... This research aims to understand more closely the damage to the lake environment and the factors that cause pollution in Lake Santa Maria are the first factor of increasing urbanization, the use of the land around the lake as a place to live, the absence of maximum control from the local government this case, the Dili municipal authority. Types of solid waste consist of iron from car accidents, motorcycles, used building materials, plastic, used drink bottles and clothes, mosquito nets, food scraps from household waste, as well as old fishing nets from residents. In addition, household waste such as bath and bath, dishwashing, detergents, and waste from tempeh and tofu factories, including burnt oil from cars and motorcycles, are thrown into the lake. Municipal waste management is based on environmental standards to determine the quality of waste management in Dili Municipality. It is possible to identify the composition of waste and waste, as well as predict its environmental impact. Human (Anthropic) factors Domestic Liquid Waste, Domestic Solid Waste: Composed of organic and inorganic waste. Synthetic Waste, Disposal of Used Oil, Disposal of Domestic Animal Waste, Shallow Drains and Septic Tanks, Mountain Garbage, Garbage Thrown by Visitors, Natural Factors, Climate change, Prolonged drought, Low rainfall, El Niño and La Niña factors, Wind speed, Heat (high daily temperature pressure), Greater water evaporation, Dry wind. The occurrence of contamination necessarily implies an ecological imbalance. The impact introduced by residual compounds and waste that may be associated with the toxicity. 展开更多
关键词 ANALYSIS the Factors cause DEGRADATION Environment Santa Maria Lake Tasi Tolu
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Multiple Indicators&Multiple Cause of Public Administration of Zoos in the Sustainable Development Goals
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作者 Leticia María González Velázquez María del Rosario Molina Gonzále +5 位作者 Gilberto Bermúdez Ruíz Arturo Sánchez Sánchez Rosa María Rincón Ornelas Lidia Amalia Zallas Esquer Jorge Hernandez Valdés Cruz García Lirios 《Journalism and Mass Communication》 2024年第5期279-288,共10页
Zoo management has been approached from its financial guidelines in accordance with the SDGs,but without considering its adjustment to the SDGs.Therefore,the objective of this work was to compare the theoretical struc... Zoo management has been approached from its financial guidelines in accordance with the SDGs,but without considering its adjustment to the SDGs.Therefore,the objective of this work was to compare the theoretical structure reported in the literature with respect to the observations of this work.A cross-sectional and retrospective study was carried out with a sample of administrative managers linked to zoos committed to the implementation of the SDGs.The results suggest that age and gender determine the financial factor.In relation to the state of the art where dimensions related to learning financial administration are reported,this work suggests that age is a determinant of social responsibility. 展开更多
关键词 Confirmatory Factor analysis Management Zoo Multiple Indicators&Multiple cause SDG`s
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Cause of over Water Quality Standard and Control Measures of State-controlled Sections in Northern Water-deficient Area of Jiangsu 被引量:5
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作者 胡永定 韩宝平 +1 位作者 钱新 袁兴程 《Meteorological and Environmental Research》 CAS 2010年第2期91-94,99,共5页
Taking state-controlled section of Xuzhou Peiyan river as an example,the current water quality was monitored,and the cause of over water quality standard was analyzed.The results showed that the pollutants of Peiyan r... Taking state-controlled section of Xuzhou Peiyan river as an example,the current water quality was monitored,and the cause of over water quality standard was analyzed.The results showed that the pollutants of Peiyan river were mainly from the urban river segment,and the immediate cause of over standard was tributary pollutants in urban river segment with the runoff into rivers.So we should strengthen the maintenance of drainage control and gate-han,accelerate the construction of urban wastewater treatment facilities and supporting pipe network,promote rural decentralized sewage treatment,prevent and control livestock and poultry pollution,pesticides and fertilizers pollution,and intercept non-point source pollution by using eco-technology. 展开更多
关键词 State-controlled sections cause analysis Control measures Water-deficient area China
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Analysis on the Cause of Dense Fog in Jining on November 10,2005 被引量:2
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作者 郭红艳 李永果 马丽 《Meteorological and Environmental Research》 CAS 2010年第5期32-33,47,共3页
Through analyzing the situation of atmospheric circulation and the variation of meteorological element at the time of dense fog happened on November 10,2005 in Jining,the results indicated that there were abundant wat... Through analyzing the situation of atmospheric circulation and the variation of meteorological element at the time of dense fog happened on November 10,2005 in Jining,the results indicated that there were abundant water vapor,weaker pressure field and wind field,weaker cold air in high altitude,stable stratification in underlying bed and ground was located in the bottom of cold high pressure,all those conditions were beneficial to the generation of dense fog in Jining. 展开更多
关键词 Dense fog cause ANALYSIS Jining China
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Analysis of the Causes of Continuous Cropping Obstacles for Atractylodes macrocephala Koidz in Pingjiang County and Its Control Methods 被引量:1
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作者 宋荣 邓凯 +2 位作者 朱校奇 周佳民 曹亮 《Agricultural Science & Technology》 CAS 2015年第3期462-466,共5页
First at all, it introduced the concept and the damages of continuous cropping obstacle. Then, it analyzed the causes of continuous cropping obstacles for Atractylodes macrocephala Koidz. In the end, in order to provi... First at all, it introduced the concept and the damages of continuous cropping obstacle. Then, it analyzed the causes of continuous cropping obstacles for Atractylodes macrocephala Koidz. In the end, in order to provide guidance for pro- moting sustainable development of Atractylodes macrocephala Koidz industry in Pingjiang County, it put forward some control methods for eliminating continuous cropping obstacles of Atractylodes macrocephala Koidz, including breeding varieties with high resistance; applying rotation cropping and intercropping reasonable; rational fertilization and soil disinfection; introducing antagonistic bacterial and eliminating au- tointoxication. 展开更多
关键词 Atractylodes macrocephala Koidz Continuous cropping obstacles cause DAMAGE Control method Pingjiang County
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Analysis of Causes for An Unusual Cloudy-rainy Weather for Several Days in Autumn 被引量:1
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作者 张景珍 张莉 +1 位作者 李建明 李静 《Meteorological and Environmental Research》 CAS 2010年第10期20-24,共5页
Cloudy-rainy weather for several days in 2007 was featured with the longest duration and the most serious extent of injury since the time from which there was meteorology observation record in Shandong.The causes of t... Cloudy-rainy weather for several days in 2007 was featured with the longest duration and the most serious extent of injury since the time from which there was meteorology observation record in Shandong.The causes of this process were analyzed in this article in terms of general circulation,character of physical quantity and tropical cyclone.The result showed that the precipitation process was a long wave adjustment process and it took place during the transformation process of general circulation turning from the zonal to the radial.During the cloudy-rainy weather process,the Ural mountain ridge and the Western Pacific subtropical high were more abnormally strong and in the further north than that in any other years.The tropical cyclone in the south of the subtropical cyclone activity was more frequent.There was more shortwave in middle latitudes of Asian.The cold air masses Siberia went down south.The cold air masses joined with the current of air in the Lower Yellow River.This led to the lasting cloudy-rainy weather for several days in Shandong. 展开更多
关键词 Cloudy-rainy weather for several days General circulation Physics characteristics Analysis of the causes China
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Statistical and causes analysis of storm surges along Tianjin coast during the past 20 years
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作者 李希彬 孙晓燕 +2 位作者 刘洋 张秋丰 牛福新 《Marine Science Bulletin》 CAS 2014年第1期15-24,共10页
Based on tidal data statistical analysis for 20 years of Tanggu Marine Environmental Monitoring Station from 1991 to 2010, we concluded that an average of nearly 10 days of 100 cm above water increase took place at Ti... Based on tidal data statistical analysis for 20 years of Tanggu Marine Environmental Monitoring Station from 1991 to 2010, we concluded that an average of nearly 10 days of 100 cm above water increase took place at Tianjin coast every year. The maximum high tide and average tide of Tianjin coast occurred in summer and autumn, and the maximum water increase also occurred in summer and autumn. Days with water increase more than 100 cm mostly occurred in spring, autumn and winter. Then we summarized the causes of coastal storm surge disaster in Tianjin based on astronomical tide factors, meteorological factors, sea level rise, land subsidence, and geographic factors, et al. Finally, we proposed storm surge disaster prevention measures. 展开更多
关键词 TIANJIN storm surge water increase statistical analysis cause analysis
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Cause Analysis on the Missing Report of First Thunderstorm Weather in Shenyang City in 2010
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作者 隋东 刘凯 +2 位作者 韦涛 祖歌 曹志贤 《Meteorological and Environmental Research》 CAS 2010年第10期71-74,共4页
The first thunderstorm weather appeared in southern Shenyang on May 2,2010 and did not bring about severe lightning disaster for Shenyang region,but forecast service had poor effect without forecasting thunderstorm we... The first thunderstorm weather appeared in southern Shenyang on May 2,2010 and did not bring about severe lightning disaster for Shenyang region,but forecast service had poor effect without forecasting thunderstorm weather accurately.In our paper,the reasons for missing report of this thunderstorm weather were analyzed,and analysis on thunderstorm potential was carried out by means of mesoscale analysis technique,providing technical index and vantage point for the prediction of thunderstorm potential.The results showed that the reasons for missing report of this weather process were as follows:surface temperature at prophase was constantly lower going against the development of convective weather;the interpreting and analyzing ability of numerical forecast product should be improved;the forecast result of T639 model was better than that of Japanese numerical forecast;the study and application of mesoscale analysis technique should be strengthened,and this service was formally developed after thunderstorm weather on June 1,2010. 展开更多
关键词 THUNDERSTORM Missing report cause analysis:Predicting vantage point China
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The Research on Development and Causes of Chinese Quadrangle Courtyards
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作者 单奇 黄谦 《Journal of Landscape Research》 2012年第2期29-32,共4页
After the illustration of the development of quadrangle courtyards,the paper has analyzed the emergence of square architectural form and the formation of axial symmetrical pattern with the hall in the front and room a... After the illustration of the development of quadrangle courtyards,the paper has analyzed the emergence of square architectural form and the formation of axial symmetrical pattern with the hall in the front and room at the back and with wing rooms on the left and right side.It has analyzed the formation,development,climax,damage and inheritance of quadrangle courtyard,and considered that it could manifest Chinese traditional humanistic idea and aesthetic idea,and is in possession of profound cultural connotation and regional feature.On this basis,causes for quadrangle courtyards have been studied.The primary cause at the initial stage lies in human body structure theory and the perfection of quadrangle courtyards at later stage depends on ethic order theory. 展开更多
关键词 QUADRANGLE courtyards DEVELOPMENT causeS
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The Study for the Causes of Pragmatic Failure
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作者 唐晓虹 严艳 《海外英语》 2012年第9X期224-226,共3页
This paper,based on the questionnaire,deduces the causes of pragmatic failure which are summarized into four:The different value orientation between the two cultures,consisting individualism versus collectivism,power ... This paper,based on the questionnaire,deduces the causes of pragmatic failure which are summarized into four:The different value orientation between the two cultures,consisting individualism versus collectivism,power distance,connotation versus denotation,and orientation towards time,negative transfer of equivalent structures and behaviors,insufficient or improper teaching and the scarcity of universal knowledge for communication. 展开更多
关键词 PRAGMATIC FAILURE cause value ORIENTATION TRANSFER
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Clinical characteristics of acute non-varicose upper gastrointestinal bleeding and the effect of endoscopic hemostasis 被引量:5
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作者 Xiao-Juan Wang Yu-Peng Shi +4 位作者 Li Wang Ya-Ni Li Li-Juan Xu Yue Zhang Shuang Han 《World Journal of Clinical Cases》 SCIE 2024年第9期1597-1605,共9页
BACKGROUND Acute non-variceal upper gastrointestinal bleeding(ANVUGIB)constitutes a prevalent emergency within Gastroenterology,encompassing 80%-90%of all gastrointestinal hemorrhage incidents.This condition is distin... BACKGROUND Acute non-variceal upper gastrointestinal bleeding(ANVUGIB)constitutes a prevalent emergency within Gastroenterology,encompassing 80%-90%of all gastrointestinal hemorrhage incidents.This condition is distinguished by its abrupt onset,swift progression,and notably elevated mortality rate.AIM To gather clinical data from patients with ANVUGIB at our hospital in order to elucidate the clinical characteristics specific to our institution and analyze the therapeutic effectiveness of endoscopic hemostasis.METHODS We retrospectively retrieved the records of 532 patients diagnosed with ANVUGIB by endoscopy at our hospital between March 2021 and March 2023,utilizing our medical record system.Data pertaining to general patient information,etiological factors,disease outcomes,and other relevant variables were meticulously collected and analyzed.RESULTS Among the 532 patients diagnosed with ANVUGIB,the male-to-female ratio was 2.91:1,with a higher prevalence among males.Notably,43.6%of patients presented with black stool as their primary complaint,while 27.4%had hematemesis as their initial symptom.Upon admission,17%of patients exhibited both hematemesis and black stool,while most ANVUGIB patients primarily complained of overt gastrointestinal bleeding.Urgent routine blood examinations at admission revealed that 75.8%of patients had anemia,with 63.4%experiencing moderate to severe anemia,and 1.5%having extremely severe anemia(hemoglobin<30 g/L).With regard to etiology,53.2%of patients experienced bleeding without a definitive trigger,24.2%had a history of using gastric mucosa-irritating medications,24.2%developed bleeding after alcohol consumption,2.8%attributed it to improper diet,1.7%to emotional excitement,and 2.3%to fatigue preceding the bleeding episode.Drug-induced ANVUGIB was more prevalent in the elderly than middle-aged and young individuals,while bleeding due to alcohol consumption showed the opposite trend.Additionally,diet-related bleeding was more common among the young age group compared to the middle-aged group.Gastrointestinal endoscopy identified peptic ulcers as the most frequent cause of ANVUGIB(73.3%),followed by gastrointestinal malignancies(10.9%),acute gastric mucous lesions(9.8%),and androgenic upper gastrointestinal bleeding(1.5%)among inpatients with ANVUGIB.Of the 532 patients with gastrointestinal bleeding,68 underwent endoscopic hemostasis,resulting in an endoscopic treatment rate of 12.8%,with a high immediate hemostasis success rate of 94.1%. 展开更多
关键词 Acute non-varicose upper gastrointestinal bleeding Clinical characteristics cause of disease Endoscopic homeostatic therapy
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Slightly Analyze the Historical Causes of Walt. Whitman's Democratic Poems
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作者 杨雪霁 《海外英语》 2011年第15期213-214,共2页
Walt·Whitman was one of the famous poets in American literary field. He is remembered by his masterpiece-Leaves of Grass, which composes a lot of his democratic ideas. His democratic poems and his writing styles ... Walt·Whitman was one of the famous poets in American literary field. He is remembered by his masterpiece-Leaves of Grass, which composes a lot of his democratic ideas. His democratic poems and his writing styles have their historical background which helped form his democratic ideas. 展开更多
关键词 analyze HISTORICAL causeS Walt·Whitman democratic POEMS
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An Analysis of the Cause of College Student’s English Classroom Silence and Its Solution from the Perspective of Pragmatics
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作者 李红霞 《海外英语》 2019年第14期85-87,共3页
This study is aimed at the common classroom silence phenomenon in contemporary college English class. First of all, thispaper explains the meaning of silence from the pragmatic point of view, and takes the students in... This study is aimed at the common classroom silence phenomenon in contemporary college English class. First of all, thispaper explains the meaning of silence from the pragmatic point of view, and takes the students in the Xi’an Innovation College ofYan’an University for instance. Based on a questionnaire survey of 200 students in the Xi’an Innovation College of Yan’an Univer-sity, the reasons are analyzed from two perspectives of teachers and students. This paper makes an analysis of all kinds of factors,so as to put forward effective solutions to eliminate the classroom silence. 展开更多
关键词 CLASSROOM SILENCE PRAGMATICS causeS COUNTERMEASURES
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Causes of the Disillusionment of Sister Carrie's American Dream
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作者 谭佳 《海外英语》 2013年第19期192-194,共3页
Theodore Dreiser’s novel Sister Carrie is the representative of studying the disillusionment of the American Dream.Since the publication of Sister Carrie,there have been many critics who commented on this work,and it... Theodore Dreiser’s novel Sister Carrie is the representative of studying the disillusionment of the American Dream.Since the publication of Sister Carrie,there have been many critics who commented on this work,and its main character Sister Carrie is a controversial person.Dreiser was criticized by critics and readers because he didn’t give any comment on her degener ation.This thesis tries to analyze the causes of this tragedy.In the end,the paper draws the conclusion:the American Dream looks beautiful,but to some extent it is not reliable,just like the foam of soap.It only gives people an illusion.So Carrie’s tragedy is in evitable. 展开更多
关键词 AMERICAN DREAM DISILLUSIONMENT TRAGEDY causeS
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Study on the Possible Cause of Water Blooming and the Bloom-Prevention Technology in Lake Qiandaohu 被引量:7
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作者 LIUQi-gen CHENMa-kang +4 位作者 TONGHe-yi HEGuang-xi HONGRong-hua CHENLai-sheng CHENLi-qiao 《Agricultural Sciences in China》 CAS CSCD 2004年第8期627-633,共7页
A hypothesis was formulated to explain the possible cause of water bloom occurring inLake Qiandaohu in 1998 and 1999. We tested this hypothesis with a 3-year in situ fieldstudy. The results showed that the reconstruct... A hypothesis was formulated to explain the possible cause of water bloom occurring inLake Qiandaohu in 1998 and 1999. We tested this hypothesis with a 3-year in situ fieldstudy. The results showed that the reconstruction of the silver carp and bighead carppopulations, without other measures of nutrient control, could prevent the recurrence ofalgal bloom in the lake successfully. This result could serve as an evidence to thesuggested hypothesis for water blooming: The drastic decline of the filter feedingsilver carp and bighead carp in the lake, rather than the nutrients overloading, wasmainly responsible for the algal bloom. According to this study, we suggest a generalhypothesis to the ecological mechanism of algal blooming: The insufficient grazing fromthe phytoplanktivores (top-down control) to the algal reproduction from nutrientsavailable (bottom-up effect) is the radical cause of water blooming, while conventionally,it is primarily attributed to the enrichment of nutrients. Besides, this study showedthat stocking silver carp and bighead carp in lakes could improve water quality, whichis also contrary to the conventional opinion. Finally, this study provided a cost-effective and practicable approach to control water bloom for the large-sized reservoirs,especially when water blooming occurred locally. A net-enclosed aquaculture zone (NEAZ)can be established in the nutrients-exposure area of the waters and stocked with the twocarps, water bloom could be controlled and prevented. 展开更多
关键词 Lake Qiandaohu Silver carp and bighead carp cause of water bloom Net-enclosed aquaculture zone (NEAZ)
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