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Nutrition impacts of non-solid cooking fuel adoption on under-five children in developing countries 被引量:1
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作者 Yalin Tang Yuhe Guo +1 位作者 Gang Xie Chengfang Liu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期397-413,共17页
This paper examines the nutrition impacts of using non-solid cooking fuel on under-five children in developing countries.We draw on data from more than 1.12 million children in 62 developing countries from the Demogra... This paper examines the nutrition impacts of using non-solid cooking fuel on under-five children in developing countries.We draw on data from more than 1.12 million children in 62 developing countries from the Demographic and Health Surveys(DHS).Results from both fixed effects(FE)and instrumental variable(IV)estimates show that using non-solid cooking fuel significantly improves the nutrition outcomes of under-five children.Compared with their peers from households mainly using solid fuel,children from households mainly using non-solid fuel exhibit a lower probability of experiencing stunting(by 5.9 percentage points)and being underweight(by 1.2 percentage points).Our further investigation provides evidence for several underlying mechanisms,such as improved indoor air quality,induced reduction in children’s respiratory symptoms,benefits on maternal health,and reduction in maternal time spent on fuel collection or cooking.Heterogenous analyses suggest that the nutrition benefits of using non-solid cooking fuel are more prominent among boys,children above three years old,and those from households of lower socioeconomic status,rural areas,and Southeast Asia. 展开更多
关键词 non-solid cooking fuel nutrition benefits under-five children developing countries
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Food Security in Developing Countries: Factors and Mitigation
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作者 Hellen Abbo Owasa Abdoulaye Fofana Fall 《American Journal of Climate Change》 2024年第3期391-405,共15页
Since 1976, eradicating hunger has become one of the priority objectives of the United Nations, which is included in the Charter of Human Rights;the right to get adequate food. The qualification of food security in ti... Since 1976, eradicating hunger has become one of the priority objectives of the United Nations, which is included in the Charter of Human Rights;the right to get adequate food. The qualification of food security in time and space must analyze not only the three components it covers but also the relationships that these three components maintain. Climate change contributes to food insecurity, but it is not the only factor. To address food insecurity in various forms, greater food security must be combined with improved sustainable agricultural practices with minimal strain on the environment. This review of literature insists on the principles of food security, which in particular allows a better understanding of food insecurity in developing countries and favors a greater contribution of agriculture and food systems in general to nutritional progress. 展开更多
关键词 Food Security developing Countries Climate Change
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Research on Developing an Assessment Scale for Tourism Experience Elements of Ancient Shu Road Heritage Trail
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作者 Wang Yuan Wang Bo Zhou Jiang 《Contemporary Social Sciences》 2024年第5期118-142,共25页
Cultural ancient roads,known in Chinese as gudao,serve as heritage trails that carry historical exchanges across various regions in China.Due to their extensive preservation,wide geographical distribution,diverse them... Cultural ancient roads,known in Chinese as gudao,serve as heritage trails that carry historical exchanges across various regions in China.Due to their extensive preservation,wide geographical distribution,diverse thematic variations,and considerable tourist appeal,these paths have emerged as representative heritage trails,increasingly transforming into a novel tourism product experience that is highly favored by tourists and recognized by government authorities.However,research on ancient roads for tourism in China currently lacks a systematic theoretical framework,as well as relevant policies,regulations,and standards to guide their practical development.Therefore,there is a pressing need to draw upon international best practices and conduct foundational research to develop an experience element system that aligns with the perceptions,behaviors,and consumption characteristics of Chinese tourists,thereby advancing theoretical exploration in this field.This study focuses on the representative Ancient Shu Road as a case study and employs a mixed-method approach that integrates qualitative and quantitative research.It aims to construct a tourist-centric scale for the experience elements of ancient road tourism while analyzing the interactive relationship between these experience elements and tourist needs.This study addresses a significant gap in the development of indicator systems for domestic studies of ancient road tourism experiences.Ultimately,the study establishes a comprehensive scale that encompasses three core categories—trail resources and environment,facilities and services,and modes of tourism activities—along with eight primary dimensions:core resources,surrounding cultural environment,surrounding natural environment,tourism reception facilities and services,infrastructure and support services,information facilities and information services,and outdoor and recreational activities.This scale consists of thirty-two specific items,providing a robust reference for future research endeavors.Additionally,the study proposes specific development strategies related to key mechanisms,spatial configuration,and facility construction to enhance the overall development of ancient road tourism. 展开更多
关键词 ancient roads heritage trails tourism experience elements scale development
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Towards Lessening Learners’Aversive Emotions and Promoting Their Mental Health:Developing and Validating a Measurement of English Speaking Demotivation in the Chinese EFL Context
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作者 Chili Li Xinxin Zhao +2 位作者 Ziwen Pan Ting Yi Long Qian 《International Journal of Mental Health Promotion》 2024年第2期161-175,共15页
While a plethora of studies has been conducted to explore demotivation and its impact on mental health in second language(L2)education,scanty research focuses on demotivation in L2 speaking learning.Particularly,littl... While a plethora of studies has been conducted to explore demotivation and its impact on mental health in second language(L2)education,scanty research focuses on demotivation in L2 speaking learning.Particularly,little research explores the measures to quantify L2 speaking demotivation.The present two-phase study attempts to develop and validate an English Speaking Demotivation Scale(ESDS).To this end,an independent sample of 207 Chinese tertiary learners of English as a Foreign Language(EFL)participated in the development phase,and another group of 188 Chinese EFL learners was recruited for the validation of the scale.Exploratory Factor Analysis(EFA)and Confirmatory Factor Analysis(CFA)were employed to determine the factor structure of the scale.The EFA results revealed a six-factor solution with Teacher-related Factors in Learning Spoken English(TFLSE),Interest and Valence in Learning Spoken English(IVLSE),Self-efficacy in Learning Spoken English(SELSE),Negative Peer Influence in Learning Spoken English(NPILSE),Undesirable Environment for Learning Spoken English(UELSE),and Negative Influence of Assessment and Learning Materials in speaking class(NIALM).In the validation phase,Confirmatory Factor Analysis(CFA)was performed to validate the internal structure of the scale.The CFA results showed that the model fits the data well.Overall,the ESDS is a robust and trustworthy psychometric tool that could be utilized to examine L2 speaking demotivation.Implications for diminishing EFL learners’demotivation,lessening their aversive emotions and promoting their mental health are also discussed. 展开更多
关键词 Demotivation for learning English speaking ESDS scale development and validation Chinese EFL learners mental health
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Challenges to establishing and maintaining kidney transplantation programs in developing countries:What are the coping strategies?
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作者 Rabea Ahmed Gadelkareem Amr Mostafa Abdelgawad +4 位作者 Nasreldin Mohammed Mohammed Ali Zarzour Mahmoud Khalil Ahmed Reda Hisham Mokhtar Hammouda 《World Journal of Methodology》 2024年第2期1-16,共16页
Kidney transplantation(KT)is the optimal form of renal replacement therapy for patients with end-stage renal diseases.However,this health service is not available to all patients,especially in developing countries.The... Kidney transplantation(KT)is the optimal form of renal replacement therapy for patients with end-stage renal diseases.However,this health service is not available to all patients,especially in developing countries.The deceased donor KT programs are mostly absent,and the living donor KT centers are scarce.Single-center studies presenting experiences from developing countries usually report a variety of challenges.This review addresses these challenges and the opposing strategies by reviewing the single-center experiences of developing countries.The financial challenges hamper the infrastructural and material availability,coverage of transplant costs,and qualification of medical personnel.The sociocultural challenges influence organ donation,equity of beneficence,and regular follow-up work.Low interests and motives for transplantation may result from high medicolegal responsibilities in KT practice,intense potential psychosocial burdens,complex qualification protocols,and low productivity or compensation for KT practice.Low medical literacy about KT advantages is prevalent among clinicians,patients,and the public.The inefficient organizational and regulatory oversight is translated into inefficient healthcare systems,absent national KT programs and registries,uncoordinated job descriptions and qualification protocols,uncoordinated on-site investigations with regulatory constraints,and the prevalence of commercial KT practices.These challenges resulted in noticeable differences between KT services in developed and developing countries.The coping strategies can be summarized in two main mechanisms:The first mechanism is maximizing the available resources by increasing the rates of living kidney donation,promoting the expertise of medical personnel,reducing material consumption,and supporting the establishment and maintenance of KT programs.The latter warrants the expansion of the public sector and the elimination of non-ethical KT practices.The second mechanism is recruiting external resources,including financial,experience,and training agreements. 展开更多
关键词 CHALLENGES Coping strategies developing countries Kidney transplantation Low resources Single-center
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New aspects of a small GTPase RAB35 in brain development and function
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作者 Ikuko Maejima Ken Sato 《Neural Regeneration Research》 SCIE CAS 2025年第7期1971-1980,共10页
In eukaryotic cells,organelles in the secretory,lysosomal,and endocytic pathways actively exchange biological materials with each other through intracellular membrane trafficking,which is the process of transporting t... In eukaryotic cells,organelles in the secretory,lysosomal,and endocytic pathways actively exchange biological materials with each other through intracellular membrane trafficking,which is the process of transporting the cargo of proteins,lipids,and other molecules to appropriate compartments via transport vesicles or intermediates.These processes are strictly regulated by various small GTPases such as the RAS-like in rat brain(RAB)protein family,which is the largest subfamily of the RAS superfamily.Dysfunction of membrane trafficking affects tissue homeostasis and leads to a wide range of diseases,including neurological disorders and neurodegenerative diseases.Therefore,it is important to understand the physiological and pathological roles of RAB proteins in brain function.RAB35,a member of the RAB family,is an evolutionarily conserved protein in metazoans.A wide range of studies using cultured mammalian cells and model organisms have revealed that RAB35 mediates various processes such as cytokinesis,endocytic recycling,actin bundling,and cell migration.RAB35 is also involved in neurite outgrowth and turnover of synaptic vesicles.We generated brain-specific Rab35 knockout mice to study the physiological roles of RAB35 in brain development and function.These mice exhibited defects in anxiety-related behaviors and spatial memory.Strikingly,RAB35 is required for the precise positioning of pyramidal neurons during hippocampal development,and thereby for normal hippocampal lamination.In contrast,layer formation in the cerebral cortex occurred superficially,even in the absence of RAB35,suggesting a predominant role for RAB35 in hippocampal development rather than in cerebral cortex development.Recent studies have suggested an association between RAB35 and neurodegenerative diseases,including Parkinson's disease and Alzheimer's disease.In this review,we provide an overview of the current understanding of subcellular functions of RAB35.We also provide insights into the physiological role of RAB35 in mammalian brain development and function,and discuss the involvement of RAB35 dysfunction in neurodegenerative diseases. 展开更多
关键词 ENDOCYTOSIS ENDOSOMES hippocampal development neurodegenerative diseases RAB35
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Establishment of human cerebral organoid systems to model early neural development and assess the central neurotoxicity of environmental toxins
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作者 Daiyu Hu Yuanqing Cao +6 位作者 Chenglin Cai Guangming Wang Min Zhou Luying Peng Yantao Fan Qiong Lai Zhengliang Gao 《Neural Regeneration Research》 SCIE CAS 2025年第1期242-252,共11页
Human brain development is a complex process,and animal models often have significant limitations.To address this,researchers have developed pluripotent stem cell-derived three-dimensional structures,known as brain-li... Human brain development is a complex process,and animal models often have significant limitations.To address this,researchers have developed pluripotent stem cell-derived three-dimensional structures,known as brain-like organoids,to more accurately model early human brain development and disease.To enable more consistent and intuitive reproduction of early brain development,in this study,we incorporated forebrain organoid culture technology into the traditional unguided method of brain organoid culture.This involved embedding organoids in matrigel for only 7 days during the rapid expansion phase of the neural epithelium and then removing them from the matrigel for further cultivation,resulting in a new type of human brain organoid system.This cerebral organoid system replicated the temporospatial characteristics of early human brain development,including neuroepithelium derivation,neural progenitor cell production and maintenance,neuron differentiation and migration,and cortical layer patterning and formation,providing more consistent and reproducible organoids for developmental modeling and toxicology testing.As a proof of concept,we applied the heavy metal cadmium to this newly improved organoid system to test whether it could be used to evaluate the neurotoxicity of environmental toxins.Brain organoids exposed to cadmium for 7 or 14 days manifested severe damage and abnormalities in their neurodevelopmental patterns,including bursts of cortical cell death and premature differentiation.Cadmium exposure caused progressive depletion of neural progenitor cells and loss of organoid integrity,accompanied by compensatory cell proliferation at ectopic locations.The convenience,flexibility,and controllability of this newly developed organoid platform make it a powerful and affordable alternative to animal models for use in neurodevelopmental,neurological,and neurotoxicological studies. 展开更多
关键词 cadmium cell death cell proliferation cortical development environmental toxins neural progenitor cells NEUROGENESIS NEUROTOXICOLOGY ORGANOIDS stem cells
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Postnatal development of rat retina:a continuous observation and comparison between the organotypic retinal explant model and in vivo development
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作者 Baoqi Hu Rui Wang +8 位作者 Hanyue Zhang Xiou Wang Sijia Zhou Bo Ma Yan Luan Xin Wang Xinlin Chen Zhichao Zhang Qianyan Kang 《Neural Regeneration Research》 SCIE CAS 2025年第3期900-912,共13页
The organotypic retinal explant culture has been established for more than a decade and offers a range of unique advantages compared with in vivo experiments and cell cultures.However,the lack of systematic and contin... The organotypic retinal explant culture has been established for more than a decade and offers a range of unique advantages compared with in vivo experiments and cell cultures.However,the lack of systematic and continuous comparison between in vivo retinal development and the organotypic retinal explant culture makes this model controversial in postnatal retinal development studies.Thus,we aimed to verify the feasibility of using this model for postnatal retinal development studies by comparing it with the in vivo retina.In this study,we showed that postnatal retinal explants undergo normal development,and exhibit a consistent structure and timeline with retinas in vivo.Initially,we used SOX2 and PAX6 immunostaining to identify retinal progenitor cells.We then examined cell proliferation and migration by immunostaining with Ki-67 and doublecortin,respectively.Ki-67-and doublecortin-positive cells decreased in both in vivo and explants during postnatal retinogenesis,and exhibited a high degree of similarity in abundance and distribution between groups.Additionally,we used Ceh-10 homeodomain-containing homolog,glutamate-ammonia ligase(glutamine synthetase),neuronal nuclei,and ionized calcium-binding adapter molecule 1 immunostaining to examine the emergence of bipolar cells,Müller glia,mature neurons,and microglia,respectively.The timing and spatial patterns of the emergence of these cell types were remarkably consistent between in vivo and explant retinas.Our study showed that the organotypic retinal explant culture model had a high degree of consistency with the progression of in vivo early postnatal retina development.The findings confirm the accuracy and credibility of this model and support its use for long-term,systematic,and continuous observation. 展开更多
关键词 bipolar cells differentiation in vivo microglia Müller glia organotypic retinal explant culture postnatal retina development proliferation retinal progenitor cells
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Ultrastructure of Epidermis and Flesh of the Developing Apple Fruit 被引量:16
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作者 彭宜本 张大鹏 《Acta Botanica Sinica》 CSCD 2000年第8期794-802,共9页
The ultrastructure of the epidermis and flesh of apple ( Malus domestica Borkh cv. Red Fuji) fruit was systematically observed during the fruit development via transmission electron microscopy. The results showed t... The ultrastructure of the epidermis and flesh of apple ( Malus domestica Borkh cv. Red Fuji) fruit was systematically observed during the fruit development via transmission electron microscopy. The results showed that, in spite of the ultrastructural changes in many aspects of the developing fruit epidermal cells, it remained almost unchanged throughout the whole developmental process that the cytoplasm was filled with numerous endoplasmic reticula (ER). Most of these endoplasmic reticula were tube_like and rough_ER with enlarged cisterna from which many vesicles were produced. Some of the vesicles were shown to merge into vacuole. Some dynamic Golgi bodies were also found. All the ultrastructural characteristics showed that the epidermal cells have the features of excretory cells. The ultrastructure of the fruit flesh cells at the young fruit stage were shown to be metabolically active, characterized by the presence of numerous clustered plasmodesmata, cisterna enlarged_ and rough_ER filling the cytoplasm, plenty of vesicles and Golgi bodies, indicating their dynamic cellular transport function. Some giant_circular rough_ERs were found. All the ultrastructural features at this early developmental stage should be closely associated with the enlargement of the young fruit. At the rapid growing phase of the fruit the main changes were characterized by: the starch grain_filled amyloplasts, furcating of the single orifice of plasmodesmata, and the cytoplasm enrichment of both the Golgi body_formed vesicles and other vesicles. These features correspond well with those of a photoassimilate sink_cell. An ultrastructural degeneration phenomenon was observed at the fruit ripening stage, but the mitochondria and plasmalemma still remained intact, which might be related to the continuous development of fruit quality during the fruit ripening. 展开更多
关键词 APPLE FRUIT EPIDERMIS FLESH ULTRASTRUCTURE fruit development
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Changes of cell proliferation and differentiation in the developing brain of mouse 被引量:1
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作者 邱林 朱长连 +1 位作者 王小阳 徐发林 《Neuroscience Bulletin》 SCIE CAS CSCD 2007年第1期46-52,共7页
Objective To investigate the cell proliferation and differentiation in the developing brain of mouse. Methods C57/BL6 mice were divided into 3 groups at random. Bromodeoxyuridine (BrdU) was injected into the brains ... Objective To investigate the cell proliferation and differentiation in the developing brain of mouse. Methods C57/BL6 mice were divided into 3 groups at random. Bromodeoxyuridine (BrdU) was injected into the brains in different development periods once a day for 7 d. The brains were retrieved 4 weeks after the last BrdU injection. Immunohistochemical and immunofluorescent studies were carried out for detecting cell proliferation (BrdU) and cell differentiation (NeuN, APC, lbal, and S 100β), respectively. Results The number of BrdU labeled cells decreased significantly with the development of the brain. Cell proliferation was prominent in the cortex and striatum. A small portion of BrdU and NeuN double labeled cells could be detected in the cortex at the early stage of development, and in the striatum and CA of the hippocampus in all groups. The majority of BrdU labeled cells were neuroglia, and the number of neuroglia cells decreased dramatically with brain maturation. Neurogenesis is the major cytogenesis in the dentate gyrus. Conclusion These results demonstrated that cell proliferation, differentiation and survival were age and brain region related. 展开更多
关键词 brain development NEUROGENESIS GLIOGENESIS
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Status quo of Agriculture in Benin and Developing Strategy
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作者 刘开强 韦宇 +4 位作者 李孝琼 陈颖 郭嗣斌 黄玉溢 高国庆 《Agricultural Science & Technology》 CAS 2015年第4期777-781,共5页
Benin, a tropical country in west Africa, is one of the Ieast deveIoped countries confirmed by the United Nations. Benin is highIy dependent on agricuIture and reIativeIy rich in agricuIture resources. It&#39;s espec... Benin, a tropical country in west Africa, is one of the Ieast deveIoped countries confirmed by the United Nations. Benin is highIy dependent on agricuIture and reIativeIy rich in agricuIture resources. It&#39;s especial y suitabIe for agricuIture be-cause of the sufficient sunIight, raln and suitabIe temperature. AgricuIture export in Benin pIays an important part for both government and farmers. But the Iack of new varieties, appropriate technoIogy and modern service makes it difficuIt to deveI-op the agricuIture production rapidIy. Based on the introduction of agricuIture re-sources incIuding cIimate and Iand, this articIe malnIy showed the maln agricuIture productions and potential probIems in Benin, and then Iooked into the distance and deveIoping strategy on how to soIve the probIems. In order to deveIop the agricuI-ture sustalnabIy in Benin, it’s also suggested that the worId shouId strengthen the ald and share the fruits of new products, appropriate technoIogy and good man-agement methods. 展开更多
关键词 AgricuIture STATUS developing strategles BENIN
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基于POA的读写结合教学实践--以外研版高中英语教材Developing Ideas板块为例 被引量:2
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作者 刘钰 张华清 《中小学英语教学与研究》 北大核心 2023年第1期49-53,共5页
读写结合是实施综合性语言学习的重要途径。产出导向法(POA)强调通过语言输入为语言输出搭建支架,有助于落实读写结合教学,实现语言文化知识的学习理解和迁移应用。本文以外研版高中英语教材Developing Ideas板块为例,阐述基于POA进行... 读写结合是实施综合性语言学习的重要途径。产出导向法(POA)强调通过语言输入为语言输出搭建支架,有助于落实读写结合教学,实现语言文化知识的学习理解和迁移应用。本文以外研版高中英语教材Developing Ideas板块为例,阐述基于POA进行高中英语读写结合教学的策略:(1)输出驱动--呈现任务、尝试写作、激发动机。(2)输入促成--以读促写、搭建支架、迁移应用。(3)以评为学--师生合作、典型分析、完善修订。在此过程中,写作任务设计、阅读文本的选择等都有所要求。 展开更多
关键词 POA 读写结合教学 外研版developing ideas板块
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On Developing the Questionnaire for Evaluating PBL's Multiple Learning Achievements
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作者 王勃然 《海外英语》 2021年第23期292-293,296,共3页
How to comprehensively,scientifically,objectively and impartially evaluate the multiple learning achievements of the PBL model should be highlighted when PBL is introduced and applied.A questionnaire of a total of 23 ... How to comprehensively,scientifically,objectively and impartially evaluate the multiple learning achievements of the PBL model should be highlighted when PBL is introduced and applied.A questionnaire of a total of 23 items involving such dimensions of language proficiency,subject contents and 21 st Century skills was designed.Its reliability and validity were tested and well-met with the statistical requirements. 展开更多
关键词 PBL multiple learning achievement EVALUATION questionnaire development
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Exploration and Practice of Developing Hybrid Rice for Realizing Food Self-sufficiency in East Timor 被引量:1
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作者 方远祥 唐启源 +2 位作者 李迪秦 张建华 黄大辉 《Agricultural Science & Technology》 CAS 2011年第11期1617-1620,F0003,共5页
The status, advantages and disadvantages of rice production in East Timor were investigated and analyzed, the results of comparison test and demonstrative cultivation through introducing 15 Chinese hybrid rice combina... The status, advantages and disadvantages of rice production in East Timor were investigated and analyzed, the results of comparison test and demonstrative cultivation through introducing 15 Chinese hybrid rice combinations into East Timor were summarized, the feasibility of developing hybrid rice in East Timor to realize food self-sufficiency were discussed and demonstrated, and the main corresponding technical strategies were proposed in this paper. 展开更多
关键词 East Timor Hybrid rice Demonstrative performance developing strategies
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Hepatitis B:Epidemiology and prevention in developing countries 被引量:41
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作者 Elisabetta Franco Barbara Bagnato +3 位作者 Maria Giulia Marino Cristina Meleleo Laura Serino Laura Zaratti 《World Journal of Hepatology》 CAS 2012年第3期74-80,共7页
Hepatitis B virus(HBV)infection is a serious global public health problem.The infection may be transmitted through sexual intercourse,parenteral contact or from an infected mother to the baby at birth and,if contracte... Hepatitis B virus(HBV)infection is a serious global public health problem.The infection may be transmitted through sexual intercourse,parenteral contact or from an infected mother to the baby at birth and,if contracted early in life,may lead to chronic liver disease,including cirrhosis and hepatocellular carcinoma.On the basis of the HBV carrier rate,the world can be divided in 3 regions of high,medium and low endemicity.The major concern is about high endemicity countries,where the most common route of infection remains vertical transmission from mother to child.Screening of all pregnant women and passive immunization with human hepatitis B immunoglobulin are not affordable for many developing countries.The infection rate can be reduced by modifying behavior,improving individual education,testing all blood donations,assuring asepsis in clinical practice and screening all pregnant women.However,availability of a safe and efficacious vaccine and adoption of appropriate immunization strategies are the most effective means to prevent HBV infection and its consequences.The unsolved problem for poorest countries,where the number of people currently infected is high,is the cost of the vaccine.A future challenge is to overcome the social and economic hurdles of maintaining and improving a prevention policy worldwide to reduce the global burden of the disease. 展开更多
关键词 HEPATITIS B developing COUNTRIES ENDEMICITY SEROPREVALENCE VACCINE
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Hepatitis A:Epidemiology and prevention in developing countries 被引量:20
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作者 Elisabetta Franco Cristina Meleleo +2 位作者 Laura Serino Debora Sorbara Laura Zaratti 《World Journal of Hepatology》 CAS 2012年第3期68-73,共6页
Hepatitis A is the most common form of acute viral hepatitis in the world.Major geographical differences in endemicity of hepatitis A are closely related to hygienic and sanitary conditions and other indicators of the... Hepatitis A is the most common form of acute viral hepatitis in the world.Major geographical differences in endemicity of hepatitis A are closely related to hygienic and sanitary conditions and other indicators of the level of socioeconomic development.The anti-hepatitis A virus(HAV)seroprevalence rate is presently decreasing in many parts of the world,but in less developed regions and in several developing countries,HAV infection is still very common in the first years of life and seroprev-alence rates approach 100%.In areas of intermediate endemicity,the delay in the exposure to the virus has generated a huge number of susceptible adolescents and adults and significantly increased the average age at infection.As the severity of disease increases with age,this has led to outbreaks of hepatitis A.Several factors contribute to the decline of the infection rate,including rising socioeconomic levels,increased access to clean water and the availability of a hepatitis A vaccine that was developed in the 1990s.For populations with a high proportion of susceptible adults,implementing vaccination programs may be considered.In this report,we review available epidemiological data and implementation of vaccination strategies,particularly focusing on developing countries. 展开更多
关键词 HEPATITIS A developing COUNTRIES Endemic-ity SEROPREVALENCE VACCINE
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Epidemiological transition of colorectal cancer in developing countries: Environmental factors, molecular pathways, and opportunities for prevention 被引量:19
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作者 Faraz Bishehsari Mahboobeh Mahdavinia +2 位作者 Michele Vacca Reza Malekzadeh Renato Mariani-Costantini 《World Journal of Gastroenterology》 SCIE CAS 2014年第20期6055-6072,共18页
Colorectal cancer(CRC)is one of the leading causes of cancer and cancer-related mortality worldwide.The disease has been traditionally a major health problem in industrial countries,however the CRC rates are increasin... Colorectal cancer(CRC)is one of the leading causes of cancer and cancer-related mortality worldwide.The disease has been traditionally a major health problem in industrial countries,however the CRC rates are increasing in the developing countries that are undergoing economic growth.Several environmental risk factors,mainly changes in diet and life style,have been suggested to underlie the rise of CRC in these populations.Diet and lifestyle impinge on nuclear receptors,on the intestinal microbiota and on crucial molecular pathways that are implicated in intestinal carcinogenesis.In this respect,the epidemiological transition in several regions of the world offers a unique opportunity to better understand CRC carcinogenesis by studying the disease phenotypes and their environmental and molecular associations in different populations.The data from these studies may have important implications for the global prevention and treatment of CRC. 展开更多
关键词 Colorectal cancer developing countries Environment DIET Nuclear receptors Gut microbiota
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Comparative analysis of open and laparoscopic colectomy for malignancy in a developing country 被引量:9
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作者 Pierre-Anthony Leake Kristen Pitzul +1 位作者 Patrick O Roberts Joseph M Plummer 《World Journal of Gastrointestinal Surgery》 SCIE CAS 2013年第11期294-299,共6页
AIM: To compare the short-term, including oncologic, outcomes of open vs laparoscopic colectomy for cancer in a developing country. METHODS: The records of patients who underwent elective open and laparoscopic colecto... AIM: To compare the short-term, including oncologic, outcomes of open vs laparoscopic colectomy for cancer in a developing country. METHODS: The records of patients who underwent elective open and laparoscopic colectomies for cancer at the University Hospital of the West Indies between January 2005 and December 2010 were retrospectively reviewed. Demographic(age, gender, Charlson comorbidity index score), peri-operative, post-operative and oncologic data were collected for each patient. Specific oncologic variables included lymph node yield, pathologic stage, grade, proximal, distal and circumferential margin involvement. Fisher's exact, Mann-Whitney, and binary logistic regression tests were used for analysis. Significance level was set atP < 0.05. RESULTS: There were 87 cases for open colectomy(OC) and 17 cases for laparoscopic colectomy(LC). Demographics did not significantly differ between OC and LC groups. Intra-operative blood loss and postoperative analgesic requirements did not significantly differ between groups. There was a trend towards longer operating times in OC group and shorter hospital stay in the LC group. Lymph node yield(14 vs 14, P = 0.619), proximal(10 cm vs 7 cm, P = 0.353) and distal(8 cm vs 8 cm, P = 0.57) resection margin distance and circumferential margin involvement(9 vs 0, P = 0.348) did not significantly differ between groups. Thirty-day morbidity was equivalent between groups(22 vs 6, P = 0.774). There were 6 deaths within 30 d of initial procedure, all in the OC group(6.9%). CONCLUSION: Laparoscopic colectomy in a developing country is oncologically safe and represents a option for colonic malignancies in these regions. Such data encourage the continued laparoscopic development. 展开更多
关键词 LAPAROSCOPY COLECTOMY Cancer developing COUNTRY COLORECTAL ONCOLOGY Short-term Outcomes
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Developing a quantitative index system for assessing sustainable forestry management in Heilongjiang Province,China: a case study 被引量:4
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作者 Jin-shan Yang Feng-you Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第3期611-619,共9页
In this study, we developed a comprehensive index system for forestry sustainability of Heilongjiang Province, which includes forest resources sustainability,sustainable economic development, sustainable social develo... In this study, we developed a comprehensive index system for forestry sustainability of Heilongjiang Province, which includes forest resources sustainability,sustainable economic development, sustainable social development and sustainable advancement in science and technology. Based on this system and the regional forest development, we further evaluated the sustainability of Heilongjiang Province for year 2008-2013. The results show that even though the regional forestry has been preliminarily on the track of sustainable development, it is fragile. Four indicators, e.g. soil and water retention rate,forest stand growth(per unit area), the proportion of national investment and the annual carbon sequestration have important impact on the sustainability, with a weight of 39.0 % in all the indicators. We also analyzed the factors hindering the sustainable development. It turns out that soil and water retention rate, forest stand growth(per unit area),the proportion of science and technology funds, per capita GDP and the proportion of the tertiary industry production are the main factors hindering regional sustainable development, which accounts for 50.94 % of the total obstacle degrees in the system. At last, we discussed how to promote the regional sustainable development from the perspectives of forest resources sustainability, economic development sustainability, society development sustainability and the sustainable advancement of science and technology. 展开更多
关键词 Regional forestry Sustainable development Index system Empirical analysis
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Structural and Histochemical Characterization of Developing Rice Caryopsis 被引量:3
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作者 YU Xu-run ZHOU Liang +1 位作者 XIONG Fei WANG Zhong 《Rice science》 SCIE 2014年第3期142-149,共8页
The development of pericarp, seed coat, starchy endosperm and aleurone of the rice caryopsis was investigated, histochemically and structurally, from the time of flowering to maturity. The results showed that during i... The development of pericarp, seed coat, starchy endosperm and aleurone of the rice caryopsis was investigated, histochemically and structurally, from the time of flowering to maturity. The results showed that during its growth, the maximum length of the caryopsis was attained first, followed by width and then thickness. Histochemical examination of the caryopsis showed that starch was mainly accumulated in the endosperm, but the endosperm showed no metabolic activity, while embryo and pericarp contained a few starch grains, and embryo and aleurone were strongly active. Aleuronic cells contained many aleurone grains and spherosomes, and aleurone in the dorsal region developed earlier and contained more layers of cells. Amyloplasts in endosperm contained many starch granules and were spherical at early stages but polyhedric at late stages. The protein bodies appeared later than amyloplasts, and the number of protein bodies in subaleurone was greater than those in the starchy endosperm. The white-belly portion of endosperm might be relative to the status of amyloplast development. 展开更多
关键词 RICE CARYOPSIS structure development CHALKINESS
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