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1.
脂肪细胞是能量储存细胞,也是活跃的内分泌细胞。现已发现人类脂肪细胞分泌几十种脂肪细胞因子,它们对机体的能量代谢及脂肪积累具有显著的调节功能。重点阐述在机体能量代谢平衡调控中起主要作用的脂肪细胞因子,并通过分析脂肪细胞因子对机体能量代谢的调节作用与肥胖之间的关系,为运动减肥和糖尿病的运动治疗提供了新的研究方向。 相似文献
2.
运动减肥机制探析———酰化刺激蛋白的作用及其调节 总被引:2,自引:0,他引:2
酰化刺激蛋白是脂肪组织分泌的一种激素,在调节脂肪代谢和能量平衡方面发挥重要作用。它一方面能够提高脂肪细胞捕获脂肪酸和合成甘油三酯的能力;另一方面可以通过抑制激素敏感脂酶的活性来抑制甘油三酯的分解。C3(-/-)(ASP缺乏)鼠所表现出的肥胖抵抗特征对于防肥减肥而言具有诱人的前景。综述了ASP的来源、生物学作用以及缺乏后的生物学特征,并对其在运动减肥机制中可能发挥的作用进行探讨。 相似文献
3.
An investigation has been undertaken at St Andrew’s church, Walpole St Andrew, Norfolk, to establish the underlying causes of the observed stone decay to the upper parts of the six stone piers. The stone decay was first recorded in the early 1930s. The salt-contaminated masonry within the church has been shown to undergo severe salt decay during the summer, with little damage occurring over the winter months. The south aisle piers have been shown to decay 2.5 times faster than the north aisle piers. Although crystallization–hydration cycles have been identified, the rate of decay is at its greatest when the cycling is relatively infrequent. This was not the expected trend. Furthermore, it has been shown that during extended periods where the ambient relative humidity is less than 75%, the rate of decay reaches a maximum. It is the length of this ‘drying’ period that apparently has the greatest influence on the rate of decay and could explain the significant difference in the rate of decay between the south and north aisle piers. The results have serious implications for passive conservation, where it is often recommended to lower the ambient relative humidity to well below the equilibrium relative humidity of the salt contaminant, to avoid crystallization–hydration cycles. Since, at the time of building, the church was situated on the coast, it is possible that the sodium chloride contamination occurred during the building process (1440–1520), particularly since the area was prone to sea-flooding at this time. Alternatively, the salt could have been applied as a treatment during the general restoration of 1897. Whatever the source of the salt, it seems likely that the ambient environment was changed by the insertion of a sealed floor in 1897, which could account for the onset of the salt decay. 相似文献
4.
Rosario Llamas-Pacheco 《文物保护研究》2018,63(8):441-449
This article presents the intervention process carried out on a work of art created by artist Yolanda Gutiérrez Acosta, using a series of ephemeral materials such as butterfly wings and agave thorns. The work, an installation from 2002, is entitled ‘Efímeras’ (‘Ephemera’) and consists of 12 flowers mounted on acetate sheets and attached to the same with vinyl acetate copolymers and acrylic acid esters (Mowilith®). These flowers are installed on the floor in a bed of dried flowers. The conservation of contemporary art can lead to some previously unimaginable problems for restorers. Current works of art are somewhat material in nature, but they also have a conceptual dimension that is essential for their artistic interpretation. The artist’s participation in the decision-making process prior to the restoration was quite useful. The passage of time, its effect on the work, and the need to understand the possibility of the demise and destruction of the work were implicit as of the onset of its creation, such that, according to the artist, we are forced to reflect upon the possibilities of its future state. 相似文献
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6.
Jane Henderson 《文物保护研究》2018,63(5):108-112
ABSTRACTThis paper examines how conservators engage with uncertainty when creating preventive conservation strategies. It argues that by recognising contexts in which uncertainty will be encountered conservators can develop effective management strategies. A typology of uncertainty explores a range of categories of uncertainty, their experience in preventive conservation and identifies distinct approaches to manage them. Managing uncertainty may include acts of defining its parameters, exposing and resolving through communication or protecting from with contingency. Whatever approach is adopted it must be accepted that uncertainty cannot be avoided. It is important therefore to aim to live well with uncertainty and the paper advocates for preventive conservation applications of strategies recommended in health care for patients with life-threatening illnesses. These strategies include working on things that can be controlled, goal setting, acceptance and factoring in emotions. The ability to identify contexts in which uncertainty is inbuilt should trigger those concerned with preventive conservation to activate strategies developed for managing and living well with uncertainty. 相似文献
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8.
ABSTRACTLighting a cultural heritage artifact requires balancing visual perception with preventive conservation, by providing the best lighting (in terms of spectral distribution and quantity) to enable the viewer to appreciate details and color, while limiting photo-induced degradation. The paper outlines the methodology applied by a multi-disciplinary team while lighting the Shroud of Turin at its last public exhibition in 2015. The methodology considered the special requirements of the Shroud, including exposure to ultraviolet light, while providing appropriate display conditions that would meet audience expectations. The desired appearance (readability of the body image and color) was defined with the help of Shroud researchers and confirmed by subjective tests, while appropriate light levels for preservation were set in agreement with standard requirements and using knowledge of the degradation of linen in visible and UV light. The installation provided a controlled environment and a managed visitor route to the Shroud, assuring excellent perception of both details and color, with the lowest illuminance level about 15?lx. 相似文献
9.
ABSTRACTWorking on preventive conservation in Italy is difficult but not impossible. After small successes and setbacks convincing museums to adopt elements of preventive conservation in the 1990s, the first author (Rossi Doria) was contracted for 15 years to preserve the historic carriages and associated objects of the Presidency of the Republic of Italy. This required patience to overcome or circumvent obstacles such as an inflexible bureaucracy and the absence of any formal recognition of preventive conservation within the educational and contractual systems for heritage conservation. The key factors in his success were the support of the curators, the financial and planning autonomy of the Presidency, and the obvious need for conservation and preservation of these elegant and complex objects. The program began in 2001 with the recovery of the forgotten collection from inappropriate storage in several locations. The entire collection was surveyed and recorded, not only the carriages but also thousands of harnesses, saddles, clothing, fabrics, weapons and memorabilia. Multiple preventive and interventive actions were undertaken, such as pest eradication for all sensitive materials, environmental surveys, and everyday maintenance, as well as complex treatments for the ornate carriages. Analysis by country of published articles on preventive conservation and of IIC membership both confirm that the topic is not as well established in Italy as in many other countries. Some reasons and solutions are proposed. 相似文献
10.
中国能源外交战略分析与思考 总被引:3,自引:0,他引:3
随着能源对于国民经济和国家安全的战略意义不断提升,各国在能源领域所开展的外交活动日益活跃,能源外交在国家总体外交中的地位迅速攀升。因此,大力加强能源外交及对能源外交理论的研究,制定与国家能源发展战略相配套的能源外交战略,在我国具有十分重要的现实意义。符合中国国情的能源外交战略,应该有其明确的内涵与定位,能够把握现存的问题并给以解决问题的出路筹谋。 相似文献