首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
目的:了解鹤岗市中小学生性健康教育现状,为进一步开展青春期性健康教育提供依据。方法:分层随机整群抽取鹤岗市1735名中小学生进行无记名问卷调查。结果:被调查的学生已具备一定的青春期性知识,但其知晓率仍偏低;性知识获取途径以社会媒体为主。大多数被调查者性生理发育状况良好,对青少年中发生的恋爱行为持宽容和理解的态度,而对婚前性行为持谨慎和保守态度。结论:今后应加大对性健康教育的宣传和投入,加强对中小学生的性道德教育。  相似文献   

2.
Although the general perception has been that Onchocerca volvulus infection is well on its way towards extinction, it is becoming increasingly clear that without an additional therapeutic or preventative modality (separate from ivermectin distribution or vector control), elimination of onchocercal infection will remain an unfulfilled goal. Vaccination aimed at preventing infection (directed toward infective-stage or adult worms), transmission and/or pathology (directed toward skin microfilariae) could provide the necessary 'final punch' to knockout human infection with O. volvulus altogether. Thus, efforts toward the development of a useful vaccine need to be redoubled rather than shelved, and, to this end, major gaps in our knowledge need to be filled.  相似文献   

3.
Teeth arise from sequential and reciprocal interactions between the oral epithelium and the underlying cranial neural crest‐derived mesenchyme. Their formation involves a precisely orchestrated series of molecular and morphogenetic events, and gives us the opportunity to discover and understand the nature of the signals that direct cell fates and patterning. For that reason, it is important to elucidate how signaling factors work together in a defined number of cells to generate the diverse and precise patterned structures of the mature functional teeth. Over the last decade, substantial research efforts have been directed toward elucidating the molecular mechanisms that control cell fate decisions during tooth development. These efforts have contributed toward the increased knowledge on dental stem cells, and observation of themolecular similarities that exist between tooth development andregeneration. Birth Defects Research (Part C) 87:199–211, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   

4.
This paper describes the present state of research on the pathogenicity of Escherichia coli and points out the gaps in knowledge that should be filled in the future. First, the great versatility of E. coli in producing disease is noted, as well as the invaluable contributions that studies of it have made to the development of general knowledge on bacterial pathogenicity. Then, the biological requirements for pathogenicity: infection of mucous surfaces; penetration of those surfaces; multiplication in vivo; interference with host defence mechanisms; and damage to the host, are taken in turn, and an enquiry is made on how far studies have progressed toward identifying their molecular determinants and relating structure to biological action. Only for mucous surface adhesins and protein toxins are studies at the structure-function level. Some progress has been made on interference with host defence, but little is known about competition with commensals on mucous surfaces, invasion into the tissues, and growth in vivo.  相似文献   

5.
MOTIVATION: Primary immunodeficiency diseases (PIDs) are Mendelian conditions of high phenotypic complexity and low incidence. They usually manifest in toddlers and infants, although they can also occur much later in life. Information about PIDs is often widely scattered throughout the clinical as well as the research literature and hard to find for both generalists as well as experienced clinicians. Semantic Web technologies coupled to clinical information systems can go some way toward addressing this problem. Ontologies are a central component of such a system, containing and centralizing knowledge about primary immunodeficiencies in both a human- and computer-comprehensible form. The development of an ontology of PIDs is therefore a central step toward developing informatics tools, which can support the clinician in the diagnosis and treatment of these diseases. RESULTS: We present PIDO, the primary immunodeficiency disease ontology. PIDO characterizes PIDs in terms of the phenotypes commonly observed by clinicians during a diagnosis process. Phenotype terms in PIDO are formally defined using complex definitions based on qualities, functions, processes and structures. We provide mappings to biomedical reference ontologies to ensure interoperability with ontologies in other domains. Based on PIDO, we developed the PIDFinder, an ontology-driven software prototype that can facilitate clinical decision support. PIDO connects immunological knowledge across resources within a common framework and thereby enables translational research and the development of medical applications for the domain of immunology and primary immunodeficiency diseases.  相似文献   

6.
Asexual reproduction through seeds, or apomixis, is widespread in angiosperms, although does not happen frequently. It occurs in no major crop plant, but its deployment in major crops would afford advantages for breeding and maintenance of hybrid genotypes. Deployment is still a long-term goal, however, since the genetic mechanisms underlying apomixis in nature have not been determined nor has the isolation of apomictic mutants in sexual plants been achieved. Nevertheless, an increasing intensity of research toward these goals over the last decade has greatly expanded our knowledge of genome structure and gene expression in naturally occurring apomicts and female gametophyte development in sexual plants. A common working hypothesis is that apomixis is a “deregulation” of sexual processes and is increasingly supported by gene expression data. Nevertheless, the search for a unique trigger that initiates apomictic development still cannot be disqualified. Further characterization of female gametophyte-related genes and genomes of apomicts and model sexual plants will be fruitful for identifying overlaps in developmental networks.

  相似文献   


7.
F Welsch 《Teratology》1992,46(1):3-14
This article describes some of the contributions that in vitro methods have made to our progress, albeit slow, toward understanding mechanisms of chemical teratogenesis. Emphasis is given to the painstaking and time consuming nature of approaches required to elucidate mechanisms. The examples considered are cyclophosphamide, 2-methoxyethanol, and retinoids. Some of the newer methods that take advantage of the recent advances in molecular biology and analytical chemistry have already been applied to studies on teratogenic mechanisms. Prospects for the 1990s are excellent and promise more rapid progress than during the past decade toward unraveling the mysteries of normal developmental biology. That knowledge in turn should be immediately applicable for investigations on developmental toxicant-induced abnormal development.  相似文献   

8.
Pneumolysin (PLY) is a cholesterol-binding, pore-forming protein toxin. It is an important virulence factor of Streptococcus pneumoniae and a key vaccine target against pneumococcal disease. We report a systematic structure-driven approach that solves a long-standing problem for vaccine development in this field: detoxification of PLY with retention of its antigenic integrity. Using three conformational restraint techniques, we rationally designed variants of PLY that lack hemolytic activity and yet induce neutralizing antibodies against the wild-type toxin. These results represent a key milestone toward a broad-spectrum protein-based pneumococcal vaccine and illustrate the value of structural knowledge in formulating effective strategies for antigen optimization.  相似文献   

9.
Many studies have examined adults’ perceptions of and attitudes toward large carnivores to assess human–wildlife conflict and inform conservation strategies, but there have been few studies concerning children. I studied secondary school students’ perceptions of and attitudes toward brown bears (Ursus arctos) and other large mammals in Turkey via a questionnaire survey. The questionnaire, consisting of 18 questions, was completed by 215 rural and 98 urban secondary school students. Both sets of students liked bears; they were also afraid of them and unsure about living with them in the future. While there were no gender differences in attitudes and perceptions, there were marked differences between urban and rural students. Urban students had less contact with nature, gained more of their knowledge about bears from documentaries, and had less positive attitudes toward bears. They were also more likely to be afraid of species not present in Turkey, for example, anaconda, while rural students were most afraid of wild boars. Factor analysis identified three important themes: familiarity with bears, conservation of bears, and experiencing conflict with bears, which explained 49.8% of the variance in attitudes toward bears. The most important factor for the development of negative attitudes toward bears was personal experience of human–bear conflict, suggesting that measures to reduce human–bear conflict in rural areas may help to sustain students’ positive attitudes toward the conservation of bears.  相似文献   

10.
Arthropods provide ecosystem services upon which humans depend, yet are declining across the globe. Arthropods are neglected from conservation efforts due to many factors that include a lack of understanding of their roles and conservation need. Knowledge gain of arthropod roles could therefore increase support for their conservation, albeit indirectly through attitude changes. Evidence suggests knowledge and attitudes are more highly correlated in children and that environmental attitudes are shaped before age 12 years. Differences in the connection between knowledge, attitudes, and behaviors toward arthropods may also be different in children from different cultures or from urban versus rural locations due to varying experiences with arthropods. We sought to understand if different types of knowledge increased positive attitudes and stated conservation-based behaviors toward insects in children in both urban and suburban schools. We conducted either a basic biology lesson or a conservation lesson on ecosystem services in both urban and suburban 4th and 5th grade classes, and used pre- and post-questionnaires to detect changes in knowledge, attitudes, and stated behavior toward arthropods. We found that urban students had significantly lower knowledge of, less positive attitudes toward, and fewer stated conservation behaviors toward arthropods but also exhibited the greatest positive changes when presented the conservation-based lesson. In addition, we found that being able to identify the type of arthropod correctly was related to more positive attitudes and stated behaviors. Finally, we found that while attitudes did not change toward some species, stated conservation behaviors did increase with knowledge of the arthropod’s role in the ecosystem. Education in urban schools, with a focus on both distinguishing arthropods as well as ecosystem services, provides the most change per effort for conservation. Arthropod lessons could be done by local professors and undergraduate students in urban classrooms or local green spaces.  相似文献   

11.
Postnatal depression (PND) is a major psychiatric challenge to women's mental health worldwide. Particularly speaking of the Asian subcontinent i.e. India and Pakistan (Indo-Pak), many women suffer through PND but remain undiagnosed, which may be due to lack of knowledge and awareness about alteration in mood and thoughts during pregnancy and after delivery. Certain factors like low socio-economic status, a history of marital violence and depression entail a higher risk of PND. In addition, one factor which remains neglected is the husband's knowledge about PND and his behaviour toward the woman suffering from PND. The husband's poor knowledge of PND and his attitude toward the mother play a vital role in the initiation of PND. Pre-delivery interventions focusing on a couple's knowledge of PND, the couple's mutual understanding/relationship and identification of the potential stressors for a depressive episode may be one way to reduce the incidence of PND among both women and men.  相似文献   

12.
The creation of a blueprint for stem cell bioprocess development that it is easily readable and shareable among those involved in the construction of the bioprocess is a necessary step toward full-fledged bioprocess integration. The blueprint provides the culturing tools and methodologies, designed to highlight knowledge gaps within biological sciences and bioengineering. This review highlights a blueprint for stem cell bioprocessing development using a landscape architecture approach that can aid the development of culture technologies and tools that satisfy the demands for stem cell-derived products for use in clinical and industrial applications. This work is intended to provide insights to cell biologists, geneticists, bioengineers, and clinicians seeking knowledge outside of their field of expertise and fosters a leap from a reductionist approach to one, that is, globally integrated in stem cell bioprocessing.  相似文献   

13.
Bats are commonly found all over the world and provide significant ecosystem services. These animals are facing serious threats due to various anthropogenic activities, including hunting. Additionally, bats are often not particularly well liked due to their non-aesthetic characteristics. A positive attitude to these animals is essential to protect them through appropriate conservation measures involving public intervention. Current high school students are the conservationists of the future, and the extent of support for bat conservation received from this and future generations is dependent upon their attitude toward these animals. It is therefore important to assess their perceptions of bats so that appropriate awareness programs can be devised, and negative attitudes (if any) rectified. The present study aimed to understand this aspect in order to provide inputs for shaping positive attitudes toward bat conservation. The study was undertaken in Barak Valley, Assam, India, where 65 bat colonies had already been recorded. A total of 3,059 high school students from 36 schools situated in their vicinity were questioned using a close-ended questionnaire to determine their perceptions. The responses received were divided among three categories: familiarity with bats, opinion on bats, and attitudes toward conservation, and were ranked on a scale of 10, based on selected aspects. Most students were awarded a score of four, indicating an average knowledge and opinion of bats. These findings suggest that awareness programs are urgently needed in schools to improve the general knowledge of and attitudes toward bats, and to inspire the next generation of bat conservationists.  相似文献   

14.
As a part of growing up, immature orangutans must acquire vast repertoires of skills and knowledge, a process that takes several years of observational social learning and subsequent practice. Adult female and male orangutans show behavioral differences including sex-specific foraging patterns and male-biased dispersal. We investigated how these differing life trajectories affect social interest and emerging ecological knowledge in immatures. We analyzed 15 years of detailed observational data on social learning, associations, and diet repertoires of 50 immatures (16 females and 34 males), from 2 orangutan populations. Specific to the feeding context, we found sex differences in the development of social interest: Throughout the dependency period, immature females direct most of their social attention at their mothers, whereas immature males show an increasing attentional preference for individuals other than their mothers. When attending to non-mother individuals, males show a significant bias toward immigrant individuals and a trend for a bias toward adult males. In contrast, females preferentially attend to neighboring residents. Accordingly, by the end of the dependency period, immature females show a larger dietary overlap with their mothers than do immature males. These results suggest that immature orangutans show attentional biases through which they learn from individuals with the most relevant ecological knowledge. Diversifying their skills and knowledge likely helps males when they move to a new area. In sum, our findings underline the importance of fine-grained social inputs for the acquisition of ecological knowledge and skills in orangutans and likely in other apes as well.

To understand the development and evolution of cognition of our closest relatives, we need to investigate their learning behavior during every-day life. This study finds that wild orangutan males and females differ in their social learning strategies and subsequent learning outcomes from an early age, underlining the general importance of, and the effects of sex on, social learning in non-human great apes.  相似文献   

15.
ABSTRACT: BACKGROUND: Government-sponsored science, technology, and innovation (STI) programs support the socioeconomic aspects of public policies, in addition to expanding the knowledge base. For example, beneficial healthcare services and devices are expected to result from investments in research and development (R&D) programs, which assume a causal link to commercial innovation. Such programs are increasingly held accountable for evidence of impact--that is, innovative goods and services resulting from R&D activity. However, the absence of comprehensive models and metrics skews evidence gathering toward bibliometrics about research outputs (published discoveries), with less focus on transfer metrics about development outputs (patented prototypes) and almost none on econometrics related to production outputs (commercial innovations). This disparity is particularly problematic for the expressed intent of such programs, as most measurable socioeconomic benefits result from the last category of outputs. METHODS: This paper proposes a conceptual framework integrating all three knowledge-generating methods into a logic model, useful for planning, obtaining, and measuring the intended beneficial impacts through the implementation of knowledge in practice. Additionally, the integration of the Context-Input-Process-Product (CIPP) model of evaluation proactively builds relevance into STI policies and programs while sustaining rigor. RESULTS: The resulting logic model framework explicitly traces the progress of knowledge from inputs, following it through the three knowledge-generating processes and their respective knowledge outputs (discovery, invention, innovation), as it generates the intended sociobeneficial impacts. It is a hybrid model for generating technology-based innovations, where best practices in new product development merge with a widely accepted knowledgetranslation approach. Given the emphasis on evidence-based practice in the medical and health fields and "bench to bedside" expectations for knowledge transfer, sponsors and grantees alike should find the model useful for planning, implementing, and evaluating innovation processes. CONCLUSIONS: High-cost/high-risk industries like healthcare require the market deployment of technologybased innovations to improve domestic society in a global economy. An appropriate balance of relevance and rigor in research, development, and production is crucial to optimize the return on public investment in such programs. The technology-innovation process needs a comprehensive operational model to effectively allocate public funds and thereby deliberately and systematically accomplish socioeconomic benefits.  相似文献   

16.
The potential of storytelling to effect change and produce new knowledge is being recognized across disciplines. Two conditions are necessary to realize these goals: first, reading of stories must be contextualized to include larger social and political landscapes; and second, how stories are read and toward what end must be closely examined. This article explores these issues with reference to the subject of the "mental health" or emotional well-being of a cohort of postrevolution Iranian women from metropolitan Vancouver, British Columbia. Reading their stories at a particular moment in time shows that well-being is essentially grounded in spaces and places where we live, work, and engage in social interactions. This commonplace knowledge, which is subdued in medical discourse, is retrieved through Iranian women's stories of life and living told at a time when their experiences, histories, and viewpoints on health are subject to erasure.  相似文献   

17.
Development of the mammalian nervous system involves generation of neurons from neural stem cells, migration of generated neurons toward genetically determined locations, extension of axons and dendrites, and establishment of neuronal connectivity. Recent progresses revealed diverse role of heparan sulfate proteoglycans in these processes. This article reviews our current knowledge about the functional roles of heparan sulfate proteoglycans in three critical events in mammalian neural development, namely neurogenesis, axon guidance, and synapse development.  相似文献   

18.
Flounder of the genus Paralichthys exhibit a unique mode of sex determination where both low and high temperatures induce male-skewed sex ratios, while intermediate temperatures produce a 1:1 sex ratio. Male differentiation is thus easily induced in genetic females creating a combination of genetic (GSD) and environmental sex determination (ESD). Since male flounder become reproductively fit at substantially smaller body sizes than females, temperature or other environmental variables that elicit lower growth rates may also influence sex differentiation toward male development. This review covers our current knowledge of sex determination and differentiation in flatfishes including possible adaptive significance of ESD and involvement of factors such as aromatase (cyp19).  相似文献   

19.
Social and economic policy issues relevant to marine aquaculture   总被引:1,自引:0,他引:1  
This paper presents a critical review of current social, economic and policy issues relevant to marine aquaculture (mariculture) in Europe. Tools for identifying the full range of social, economic and environmental issues that influence the sustainable development of mariculture are examined. Under present sectoral approaches to policy, investment, development planning and natural resources management, these issues continue to be treated in isolation. The four main challenges presented in this paper are: (i) how to create a more objective information base with which to assess the social, economic and environmental factors that condition the sustainability of mariculture; (ii) how to provide information from different disciplines in an easy to obtain and compatible format; (iii) how to better integrate knowledge and skills from different disciplines to create a holistic and robust framework for assessing options for mariculture development that integrates social, economic and environmental parameters; and (iv) the effective integration of these assessments into the formulation of policy, investment strategies, spatial plans and natural resources management for coastal areas. Specific issues that need to be addressed within the framework for the integrated evaluation of the economic, social and environmental parameters governing the sustainable development of mariculture include: ? development of more accurate information on the economic, social and environmental benefits and costs of well‐planned and managed mariculture; ? clearer definition of gaps in existing knowledge on factors critical to the sustainable and equitable development of mariculture; ? development of pro‐active consideration of the coastal land and water resource requirements of mariculture as part of strategic economic planning, spatial planning and natural resources management; ? the need for more equitable treatment of mariculture regarding rights of access to sites for development and use of resources; ? development of awareness among decision‐makers, planners, and managers from different sectoral agencies of the contribution that mariculture may make in promoting the sustainable use of coastal ecosystems; ? promotion of a shift in emphasis away from controlling the end use of resources and toward a more balanced approach to coastal development where emphasis is also given to maintaining the health and productivity of coastal ecosystems and the resources they generate that sustain different forms of activity, including mariculture.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号