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71.
引起大气二氧化碳缓慢增加的自然界地球化学过程,通过温室效应很可能引起了过去全球变暖的一些地质时期的出现。  相似文献   
72.
薄形电视     
  相似文献   
73.
等离子体中产生的电场能够使电子加速以获得高能。这个方法可望使场强比能量最大的传统加速器的场强高出10,000倍。  相似文献   
74.
太阳能电池     
D.E 《科学中国》1990,(12):76-77
可弯曲的轻质太阳能电池展开竞争  相似文献   
75.
A century before the outbreak of bovine spongiform encephalopathy (BSE), Great Britain and North America grappled with pleuro-pneumonia - a disease in cattle that had equally maddening consequences. Towards the end of the 19th century, this condition was at the heart of a transatlantic trade dispute that lasted for decades and attracted the attention of livestock farmers, diplomats, shipping moguls, veterinarians, public health regulators and journalists the world over. Scientific controversy aggravated the situation when there were doubts about the scientific judgment of Privy Council veterinary officials, who were simultaneously conducting disease-diagnosis activities and pushing for tighter regulations at British ports. At this point, William Williams, principal of the New Veterinary College in Edinburgh, waded into this troubled arena. His strong convictions spawned a long-running disagreement with the British Government over the diagnoses of pleuro-pneumonia in cattle imported from the USA and Canada.  相似文献   
76.
77.
OBJECTIVES: The objectives of this work were to identify the sources of information currently received, information-seeking behaviours, information requirements and preferences for future information provision amongst health and social care professionals providing care to children with health care needs. METHODS: Data were collected using a cross-sectional postal questionnaire survey. RESULTS: A wide range of information resources was reported as being available to professionals. However, a large proportion of respondents found it necessary to perform additional searches for information, suggesting that current resources were not satisfying their needs. The majority of professionals reported a preference for electronic formats, whilst a smaller proportion preferred hard copy materials. Participants promoted the use of informal networks as a means of support and exchange of information. CONCLUSION: Supplementing the information that is provided in electronic and hard copy formats, by enhancing informal networks, may be the most effective way of meeting the information needs of this group of professionals.  相似文献   
78.
Chile is in the throes of health reforms aimed at ensuring that every person with specified chronic diseases receives timely and high quality care. CITs are crucial to the achievement of this vision because they make it possible to manage information and knowledge in a more efficient way. Until a few years ago, the incorporation of CITs was limited to individual initiatives, but since 2004 there has been a master plan to coordinate this task in the public sector. Some projects are now operative but there is still a long road to travel before getting to our destination. One of the most underdeveloped areas is the clinical applications of health CITs, especially the incorporation of biomedical knowledge to clinical practice. The two biggest challenges facing the Digital Agenda for the health care system are (i) to develop a critical mass of clinicians and health related professionals with expertise in Health Informatics; and (ii) to foster technical integration of the private and public sectors of the health care market.  相似文献   
79.
有人认为Google大量地数字化图书馆的馆藏图书,犹如给实体图书馆和图书馆员敲响了丧钟,还有一些人则认为Google此举是对版权法的挑衅。Google如何处理那些数字化图书是媒体报道的焦点。尽管Google的意图为人们所津津乐道,每个人都在期待着法院对版权纠纷的判决,人们也不禁想要知道:参与Google图书搜索项目的图书馆,如何使用那些从合作中得到的数字化拷贝呢?  相似文献   
80.
This updated edition of Care Practice Paper #3 presents the evidence for the benefits of continuous support in labor. The role of the doula is explained. Women are encouraged to plan for continuous support during labor and to consider including a woman experienced with childbirth among their labor support team.  相似文献   
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