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131.
股骨头坏死(ONFH)是一种进展性和致残性疾病,保存自身股骨头是临床治疗所追求的最理想目标,早中期的治疗方案主要采用非手术疗法和保髋的姑息性手术,目前为止还没有一种治疗方法能达到理想的治疗效果。近年来,骨髓间充质于细胞(MSCs)移植治疗ONFH是目前研究热点之一,有望成为一种有效的治疗方法,晚期行人工髋关节置换术是唯一的和最佳的选择。因此,早期诊断,采用综合性治疗方案保全自身髋关节是治疗本病的主要方向。  相似文献   
132.
Tadej Strehovec 《Zygon》2009,44(4):797-806
Biotechnology deals not only with new types of therapies for preventing and curing diseases but also with the creation of new technologies for the production of human flesh. Its ultimate aim is to create a new human body, a new person. Biotechnology wears the cloak not only of a new scientific paradigm but also of a kind of messianic religion. To develop new therapies, to destroy illnesses, to transform the human body into a nonmortal one—these are some of the promises it makes. In time, many of these promises will undoubtedly prove to be illusory, but they will nevertheless continue to have a significant impact on the way people think. Through a process that I call biotechnotheological analysis I show that biotechnology could eventually become not only a type of secular religion but even a type of mythic para‐Christian religion, one that incorporates the two most significant processes at work in every mythical religion: the process of mimesis and the ritual of the scapegoat. The essay is an attempt to understand biotechnological achievements, especially in stem‐cell research, in this new biotechnotheological way.  相似文献   
133.
胰岛细胞再生是治愈1型糖尿病和胰岛β细胞功能丧失的2型糖尿病的根本途径。体外再生和体内再生两种策略都是通过将干细胞或其他类型体细胞分化或转化为胰岛细胞后发挥胰岛素分泌功能,从而治疗糖尿病。基础研究显示,两者存在着各自的优势和面临的问题。胰岛细胞再生治疗的临床应用前景尚需要进一步加以考证。  相似文献   
134.
在前列腺癌的治疗中,由于癌细胞的不断“升级”使得治疗屡屡受挫。近来提出的肿瘤干细胞理论认为:肿瘤是一种干细胞疾病,只有消灭了“种子”,才能克服癌症。从自然辩证法的角度,结合肿瘤干细胞理论对前列腺癌的诊疗加以分析,解释非雄激素依赖型前列腺癌的发病机制,以一种新的思维指导临床治疗。  相似文献   
135.
植入前组织配型孕育“救星同胞”的伦理思考   总被引:1,自引:0,他引:1  
应用植入前遗传学诊断技术在胚胎植入母体子宫前,对人类白细胞组织相容性抗原配型检测,选择与现存患儿相同HLA配型的胚胎进行受孕,孕育一个组织配型相同的脐带血干细胞供者。在某种意义上说,该项技术的应用是创造人来获得移植组织,由此引发系列伦理争议。讨论孕育"救星同胞"这一医学实践内在需要的伦理规范。  相似文献   
136.
In this study, the spatial limits of referred touch to a rubber hand were investigated. Participants rated the strength of the perceived illusion when the rubber hand was placed in one of six different spatial positions (at a distance of 17.5-67.5cm horizontal from the participant's own hand). The results revealed a significant nonlinear relationship in the strength of the illusion, with the strongest ratings given when the two hands were closest; decaying significantly after a distance of 30cm. The time taken to elicit the illusion followed a similar trend. These results may reflect the response properties of bimodal visuo-tactile cells encoding peripersonal space around the hand.  相似文献   
137.
Interactions with neocortical memory systems may facilitate flexible information processing by hippocampus. We sought direct evidence for such memory influences by recording hippocampal neural responses to a change in cognitive strategy. Well-trained rats switched (within a single recording session) between the use of place and response strategies to solve a plus maze task. Maze and extramaze environments were constant throughout testing. Place fields demonstrated (in-field) firing rate and location-based reorganization [Leutgeb, S., Leutgeb, J. K., Barnes, C. A., Moser, E. I., McNaughton, B. L., & Moser, M. B. (2005). Independent codes for spatial and episodic memory in hippocampal neuronal ensembles. Science, 309, 619-623] after a task switch, suggesting that hippocampus encoded each phase of testing as a different context, or episode. The task switch also resulted in qualitative and quantitative changes to discharge that were correlated with an animal's velocity or acceleration of movement. Thus, the effects of a strategy switch extended beyond the spatial domain, and the movement correlates were not passive reflections of the current behavioral state. To determine whether hippocampal neural responses were unique, striatal place and movement-correlated neurons were simultaneously recorded with hippocampal neurons. Striatal place and movement cells exhibited a response profile that was similar, but not identical, to that observed for hippocampus after a strategy switch. Thus, retrieval of a different memory led both neural systems to represent a different context. However, hippocampus may play a special (though not exclusive) role in flexible spatial processing since correlated firing amongst cell pairs was highest when rats successfully switched between two spatial tasks. Correlated firing by striatal cell pairs increased following any strategy switch, supporting the view that striatum codes change in reinforcement contingencies.  相似文献   
138.
Stephen M. Modell 《Zygon》2007,42(1):163-182
Since the gene splicing debates of the 1980s, the public has been exposed to an ongoing sequence of genetic and reproductive technologies. Many issue areas have outcomes that lose track of people's inner values or engender opposing religious viewpoints defying final resolution. This essay relocates the discussion of what is an acceptable application from the individual to the societal level, examining technologies that stand to address large numbers of people and thus call for policy resolution, rather than individual fiat, in their application. A major source of guidance is the “Genetic Frontiers” series of professional dialogues and conferences held by the National Conference for Community and Justice from 2002 to 2004. Genetic testing, human gene therapy, genetic engineering of plants and animals, and stem cell technology are examined. While differences in perspective on the beginning of life persist, a stepwise approach to the examination of genetic testing reveals areas of general agreement. Stewardship of life, human co‐creativity with the divine, and social justice help define the bounds of application of genetic engineering and therapy; compassionate care plays a major role in establishing stem cell policy. Active, sustained dialogue is a useful resource for enabling sharing of religious values and crystallization of policies.  相似文献   
139.
骨延长愈合与骨折愈合等多种多样的骨修复现象可能具有相同的细胞生物学基础,这个理论称为骨修复一元论.血管内皮细胞是启动骨修复的感受器,破骨细胞通过分泌骨形态发生蛋白(BMP)启动骨特异性修复.骨折间隙间断性的力学脉冲通过血管内皮细胞不断地转化为骨修复的生物学脉冲.在微损伤条件下,骨修复具有放大效应.保护下负重和功能锻炼是下肢骨骼延长术后的重要原则.  相似文献   
140.
When Darwin wrote his ‘On the origin of species…” (1859) he focused on evolution as a property of living organisms in interaction with abiotic and biotic elements in the world. This viewpoint is still dominant amongst biologists. For particle physicists and cosmologists evolution refers to a larger scale, ranging from quarks and atoms to galaxies, stars and planets (i.e. Pagels 1985, Hawking 1988). To close the gap between such different viewpoints, a wide range of perspectives on an interdisciplinary understanding of system development has been published (i.e. Teilhard de Chardin 1966, von Bertalanffy 1968, Varela 1979, Prigogine and Stengers 1984, Laszlo 1996). As an integrative concept, the construction of nature from a hierarchy of system layers forms a central tenet in general system research and the stepwise construction of this layered hierarchy can be regarded as an interdisciplinary evolution theory. Surprisingly, the literature offers no unequivocal rules to recognise a multilayer hierarchy in nature. This presents an obstacle for interdisciplinary approaches to evolution.

Searching a solution to part of the above hierarchy problem, the present paper is dedicated to the analysis of a special kind of layering in natural systems, which is based on transitions between ‘building block’ systems. To identify these building blocks, and the transitions from building block x at level A, to building block y at level B, the focus of this study is further limited to ‘hypercydic dynamics’ and ‘containment’. On the basis of these criteria, a hierarchy is created which shows no possibilities for ‘bypasses’. It connects hadrons to atoms, atoms to cells, and cells to neural networks. Implications of this hierarchy for system studies and evolution are discussed.  相似文献   
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