首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   61篇
  免费   8篇
  国内免费   8篇
  2023年   5篇
  2022年   4篇
  2021年   4篇
  2020年   5篇
  2019年   6篇
  2018年   4篇
  2017年   2篇
  2016年   3篇
  2015年   1篇
  2014年   5篇
  2013年   11篇
  2012年   3篇
  2010年   2篇
  2009年   5篇
  2008年   1篇
  2007年   3篇
  2006年   1篇
  2005年   4篇
  2004年   2篇
  2002年   2篇
  2001年   2篇
  2000年   1篇
  1999年   1篇
排序方式: 共有77条查询结果,搜索用时 15 毫秒
21.
22.
A three-dimensional tissue was fabricated by layering cell sheets with centrifugation. In this system, an optimal centrifugal force promoted the adhesion between (a) a cell sheet and a culture dish, and (b) layered cell sheets, resulting in a significant decrease in the fabrication time of the tissue. However, negative effects like sliding/significant deformation of cell sheets were observed upon high rotational speed use. These negative effects inhibit the further shortening of the fabrication time. The sliding/deformation suggests that the centrifugal forces were applied on the cell sheets in unwanted directions. Studies on the force vector field applied to the object placed on the plate during centrifugation are not available, and thus, the reason for the occurrence of such negative effects is unclear. Here, we theoretically derived the spatial distribution of acceleration applied on a plate during centrifugation. Using this theory, we found that the negative effects were triggered by the centrifugal force in the direction parallel to the plate surface, which appeared due to an inclination of the plate surface against a horizontal plane. Therefore, by adding weights on the plate edge to maintain the plate surface in a horizontal position, we succeeded in eliminating the negative effects and in increasing the rotational speed, with the minimum risk of sliding/deformation of cell sheets. We succeeded in reducing the time to establish tight adhesion between a mouse myoblast sheet and a culture dish, and layered cell sheets by increasing the centrifugal force from 5 min to 1 min without significant cytotoxicity.  相似文献   
23.
INTRODUCTION Today, Acquired Immunodeficiency Syndrome (AIDS) has become a public health and social problem that has caused significant harm to the survival and development of humanbeings. Route of transmission of Human Im- munodeficiency Virus (HIV) is still predominantly through shared syringes by drug abusers. Currently, there is no efficient medicine, treatment or educational method to prevent HIV transmission in China. Intervention is prob- ably the best “vaccine” [1]. Despi…  相似文献   
24.
程绍文  张捷  徐菲菲 《生态学报》2010,30(23):6487-6494
居民的自然保护态度对自然旅游地的自然保护与旅游可持续发展至关重要,自然旅游地居民自然保护态度的影响因子及影响方式,已经成为自然旅游地管理的重要内容,但相关研究薄弱。以中国九寨沟和英国新森林国家公园(New Forest National Park,NF)为例,根据实地问卷调查数据,从两地居民的人口属性、旅游环保期望、旅游环境影响感知及旅游环境伦理观与其自然保护态度关系的角度,进行定量比较研究。研究发现:(1)两地居民的自然保护态度受不同因子的影响,存在明显的中外差异;(2)人口属性特征如性别、年龄、居住年限、教育水平及旅游业参与情况对新森林国家公园社区居民的自然保护态度没有影响;但性别、旅游业参与情况却影响九寨沟居民的自然保护态度,女性及旅游业参与者更支持对九寨沟进行自然保护;(3)新森林国家公园居民的自然保护态度受其旅游环保期望及旅游环境伦理观的影响:旅游环保期望较高、持保护主义环境伦理观的新森林国家公园居民,更有可能支持对新森林国家公园进行自然保护;(4)九寨沟居民的自然保护态度不受其旅游环保期望及旅游环境伦理的影响,但受其旅游环境影响感知的影响;居民的旅游环境影响感知越消极,越支持对九寨沟进行自然保护。  相似文献   
25.
Objective: The aim of the study was to reveal barriers to providing dental care for residents in long‐term care (LTC) facilities. Design: Participants were selected randomly from the dentist register in Berlin and Saxony, Germany. The sample consisted of 60 self‐employed and 60 employed dentists, a further 60 dentists worked in their own dental practice but also part‐time in an LTC facility. In semi‐structured interviews a questionnaire with 36 statements concerning working conditions, administration and cost, insecurity concerning treatment decisions as well as confrontation with ageing and death was employed. Subsequently, the study participants were asked to rank the four dimensions concerning their impact on the decision against providing dental care in an LTC facility. Results: The random sample was representative in age and gender for the dental register in Berlin and Saxony. Fifty‐six per cent of the participants (63% of the men and 51% of the women; 52% of the self‐employed, 60% of the employed and 56% of the consultant dentists) indicated unfavourable working conditions as biggest obstacle in providing dental care in an LTC‐facility. Thirty‐two per cent of participants rated administration and cost, 7% the insecurity in treatment decisions as major hindrance. Only 5% of the participants rated the confrontation with age and death as substantial barrier. There were no age and gender differences. Dentists in Berlin seemed more concerned about administration and cost of a consultancy activity and less secure in their therapy decisions than the colleagues from Saxony (p < 0.001). Dentists who work partly in LTC facilities were the least concerned about the confrontation with ageing and death (not significant), employed dentist showed the least secure in their treatment decisions (p > 0.001). Conclusion: It can be concluded that the awareness of infra‐structural and financial aspects in providing dental care in LTC facilities should be raised with health politicians and that these aspects should be considered when inaugurating or re‐structuring the consultancy services to LTC facilities. Further it would be desirable to establish more postgraduate training programmes to increase clinical and ethical competence in the area of gerodontology.  相似文献   
26.
崔严  张红  郝晓敬  张霄羽 《生态学报》2020,40(19):6821-6830
矿产资源的开发,在支撑社会经济发展的同时,造成了区域资源和生态环境的改变,极大影响农户的生计方式和生活环境。基于高分辨率遥感影像分析了山西省阳泉矿区典型村庄煤矿开采前后的土地利用变化,基于可持续生计框架(Sustainable Livelihoods Framework,SLF)和参与式农村评估法(Participatory Rural Appraisal,PRA),研究了矿区农户的生计动态及不同类型失地农户的生计可持续能力。结果表明:1)煤矿开采改变了村庄土地利用格局。耕地大面积减少,由占区域面积69.72%降为29.42%;工矿用地大幅度增加,由占区域面积7.51%增为25.01%;农村建设用地、林地、草地和水域均有不同程度的增加。2)农户的资本组合及生计方式随着煤矿开采呈现相应的动态变化,农户逐渐呈现兼业特性;不同类型失地农户的生计资本存在显著性差异。3)生计资本结构的不同造成农户生计可持续发展能力不平等,生计资本累计值越大,农户的生计可持续性越强。矿区农户生计的研究为促进农户生计资本合理配置、缓解矿区企业与农户利益冲突提供了科学依据。  相似文献   
27.

Introduction:

There is a global consensus that early diagnosis and treatment of tuberculosis (TB) can accelerate its control and mitigate its consequences. The gradual increase in the TB mortality rate from 2014 to 2018 in Honduras, the reform of the health system in 2014, and the partial implementation of the “End TB” strategy motivated this study.

Objective:

To analyze barriers to and facilitators of diagnosis and treatment affecting the national TB program coverage using data from 2015 to 2019 and provide tools for the effective implementation of the “End TB” strategy in San Pedro Sula, Honduras.

Materials and methods:

This was an explanatory sequential mixed-methods study on smear-positive pulmonary TB patients older than 18 years of age. TB notification sheets and medical records from two primary health care facilities were reviewed. Semistructured interviews were conducted with health care providers, patients, and their families.

Results:

A total of 74.6% of the cases (297/398) did not receive a timely diagnosis; 62.3% (185/297) were men, 80.8% (240/297) were adults, 53.7% (108/297) had less than high school education, 49.2% (123/297) had some occupation, and 98.2% of participants received timely treatment. Identified barriers included low socioeconomic conditions, lack of coordination between public and private health systems, and boundaries set by gangs. Identified facilitators included good care and attitude of the health care personnel and the availability of medications.

Conclusions:

The lack of opportunity to diagnose the disease affected the coverage of the national TB program due to cultural and health care barriers.  相似文献   
28.
Land managers use a variety of labor sources to implement ecological restoration projects. Reasons why these land managers decide to use or not use volunteer labor are not well known; yet, this decision can significantly shape ensuing social, psychological, and ecological benefits. To better understand how land managers' opinions influence their intentions toward using volunteers, we surveyed ecological restoration project decision makers (n = 176) from three U.S. land management agencies (the Bureau of Land Management, National Park Service, and U.S. Forest Service) in Colorado, Idaho, Utah, and Wyoming using stratified random cluster sampling. Employing the Theory of Planned Behavior, we measured factors that likely influence intention to use volunteers, including land managers' attitudes, norms, and perceived behavioral control (PBC). We used multiple regression analysis to understand the relationships among constructs, which indicated PBC was the strongest predictor of intention. Based upon intention to use volunteers, an analysis of variance (ANOVA) showed differences among land managers in terms of (1) their opinions about building community support and accomplishing more work, (2) the influence of supervisors, coworkers, and environmental groups, and (3) their perceived barriers due to a lack of trained volunteers and a lack of tasks safe for volunteers. Our results suggest environmental stewardship organizations and others that want to increase the use of ecological restoration volunteers should find ways to alleviate employees' perceived barriers, encourage supervisors to advocate for using volunteers, and when possible provide tangible information demonstrating how using volunteers can generate community support for a restoration project.  相似文献   
29.
New Books     
《Anthrozo?s》2013,26(4):387-389
ABSTRACT

Past research found that positive attitudes toward animals are positively correlated with human-directed empathy. One of the most common reasons for becoming a vegetarian is to avoid cruelty toward animals. Based on the above literature, we hypothesized that vegetarians, especially moral vegetarians, would show higher human-directed empathy and more positive attitudes toward pets and other animals than non-vegetarians. Seventy-two vegetarians and 67 non-vegetarians participated in the study. Pet attitudes were measured using the modified Pet Attitude Scale (PAS-M), and human-directed empathy was measured with the Interpersonal Reactivity Index (IRI), which has four subscales. Vegetarian males had significantly higher empathy and significantly more positive attitudes toward pets compared with non-vegetarian males; however, there was no differences among females. There were no differences between moral vegetarians and non-moral vegetarians on human-directed empathy and attitude toward pets. Empathy toward humans and attitudes toward pets were positively correlated for both vegetarians and non-vegetarians. We conceptualized the dietary choice of a vegetarian as a lifestyle that can be explained by their political thinking, personality, and personal value systems.  相似文献   
30.
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