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.
DeWitt N 《Nature》2008,453(7193):301
  相似文献   

2.
3.
Ali RR  Sowden JC 《Nature》2011,472(7341):42-43
  相似文献   

4.
5.
6.
7.
8.
9.
10.
Recently, regenerative medicine has been focused on as next-generation definitive therapies for several diseases or injuries for which there are currently no effective treatments. These therapies have been rapidly developed through the effective fusion be- tween different fields such as stem cell biology and biomaterials. So far, we have proposed "cell sheet engineering" through our core technology that simply applies alterations of the temperature which allows regulation of the attachment or detachment of living cells on the culture surfaces grafted with the temperature-responsive polymer "poly(N-isoproplyacrylamide)". This tech- nology enables us to construct bioengineered sheet-like tissues, termed "cell sheets", without the need of using biodegradable scaffolds and protease treatments that are traditionally used. Therefore, our carrier-free cell sheets not only are independent of the issues observed in conventional methods, but also showed further advantages in the reconstruction of the corneal epithelium or endothelium (e.g. improvement of optical transparency and cell-cell interactions to host stroma in reconstructed tissues). Moreo- ver, our approach does not have issues such as immune rejection or limited number of donors, due to the use of cell sheets derived from autologous limbal (in patients with unilateral disease) or oral mucosal epithelial cells (in patients with bilateral disorders). Indeed, we have successfully performed the clinical application for the reconstruction of ocular surfaces through the transplanta- tion of our carrier-free corneal epithelial cell sheets, as evidenced by improved visual acuity as well as long-term maintenance of postoperative health conditions on ocular surfaces in all patients. We have also proposed a novel approach for the reconstruction of the corneal endothelium using corneal endothelial cell sheets by demonstrating its successful application. Thus, our cell sheet engineering technique provides a breakthrough in the field of regenerative medicine applied to the cornea.  相似文献   

11.
Angiogenesis in life, disease and medicine   总被引:1,自引:0,他引:1  
Carmeliet P 《Nature》2005,438(7070):932-936
The growth of blood vessels (a process known as angiogenesis) is essential for organ growth and repair. An imbalance in this process contributes to numerous malignant, inflammatory, ischaemic, infectious and immune disorders. Recently, the first anti-angiogenic agents have been approved for the treatment of cancer and blindness. Angiogenesis research will probably change the face of medicine in the next decades, with more than 500 million people worldwide predicted to benefit from pro- or anti-angiogenesis treatments.  相似文献   

12.
Human pluripotent stem cells (PSCs) are a promising source of cells for applications in regenerative medicine. Directed differentiation of PSCs into specialized cells such as spinal motoneurons or midbrain dopamine (DA) neurons has been achieved. However, the effective use of PSCs for cell therapy has lagged behind. Whereas mouse PSC-derived DA neurons have shown efficacy in models of Parkinson's disease, DA neurons from human PSCs generally show poor in vivo performance. There are also considerable safety concerns for PSCs related to their potential for teratoma formation or neural overgrowth. Here we present a novel floor-plate-based strategy for the derivation of human DA neurons that efficiently engraft in vivo, suggesting that past failures were due to incomplete specification rather than a specific vulnerability of the cells. Midbrain floor-plate precursors are derived from PSCs 11 days after exposure to small molecule activators of sonic hedgehog (SHH) and canonical WNT signalling. Engraftable midbrain DA neurons are obtained by day 25 and can be maintained in vitro for several months. Extensive molecular profiling, biochemical and electrophysiological data define developmental progression and confirm identity of PSC-derived midbrain DA neurons. In vivo survival and function is demonstrated in Parkinson's disease models using three host species. Long-term engraftment in 6-hydroxy-dopamine-lesioned mice and rats demonstrates robust survival of midbrain DA neurons derived from human embryonic stem (ES) cells, complete restoration of amphetamine-induced rotation behaviour and improvements in tests of forelimb use and akinesia. Finally, scalability is demonstrated by transplantation into parkinsonian monkeys. Excellent DA neuron survival, function and lack of neural overgrowth in the three animal models indicate promise for the development of cell-based therapies in Parkinson's disease.  相似文献   

13.
Kentsis A 《Nature》2006,441(7092):E5; discussion E5-E5; discussion E6
A stochastic queue model of human behaviour developed on the basis of the distribution of timing of tasks, as studied in a sample of e-mail messages at a university and in the written correspondence of Albert Einstein, may not be as simple as it seems. Although this model reproduces the apparently non-Poisson distribution of correspondence delays, its interpretation is more complicated than suggested by Barabási, who claims that humans execute their tasks based on some perceived priority, setting up queues that generate very uneven waiting-time distributions for different tasks. Such an explanation is intuitively appealing in the context of the queue metaphor, but does not exclude other mechanisms. By attributing delays in the correspondence to task priorities, this explanation ignores two important classes of mechanism that also contribute to the apparent distributions of task timings: the semantic content of an individual's correspondence and the social context in which this correspondence occurs.  相似文献   

14.
L-asparaginase and human malignant disease   总被引:5,自引:0,他引:5  
D Crowther 《Nature》1971,229(5281):168-171
  相似文献   

15.
观察了运用自拟治带汤加减和佳丽康阴道泡腾片相结合治疗带下病的疗效.将270例带下病患者随机分为中西药结合、西药和中药3组进行治疗.中西药结合组运用自拟治带汤加减煎服,每日一剂,同时每晚睡前阴道内放置佳丽康阴道泡腾片1片;西药组口服替硝唑、阿莫灵或氧氟沙星等消炎药,并用同样方法放置佳丽康阴道泡腾片;中药组单用自拟治带汤加减煎服.3组均治疗10 d.中西药结合治疗组总有效率为99%,西药组总有效率为72.22%,中药组总有效率为76.25%(P<0.05).中西药结合治疗带下病疗效优于单纯的西药或中药,值得临床广泛应用.  相似文献   

16.
蒜头果组织培养再生系统的初步研究   总被引:7,自引:0,他引:7  
以蒜头果(Malania oleifera)种子萌发获得的无菌苗进行离体培养的初步研究.结果表明:MS+6-BA1.5mg/L+NAA0.1mg/L激素组合能够较好地诱导芽的初始分化和增殖;适宜的继代增殖培养基为MS+6-BA1.0mg/L+NAA0.2mg/L;采用1/2MS+IBA0.5mg/L为生根培养基,生根率为45.0%;移栽到河沙的生根苗成活率为52.5%.  相似文献   

17.
蓄热式原油加热炉的开发研究   总被引:1,自引:1,他引:0  
介绍了一种新型蓄热式原油加热炉的工作原理及结构特点·该加热炉采用填充球蓄热室进行余热回收,保证炉子排烟温度在200℃以下,从而使炉子的运行效率在80%以上·应用结果表明,该炉可比原有水套加热炉热效率提高2141%,节能率达到357%·  相似文献   

18.
已有的脑成像研究表明,个体在社会博弈中的合作决策主要激活与认知控制、社会认知以及奖励加工有关的三类大脑神经网络.首先对上述三类大脑系统的功能及其相应的大脑结构和神经回路进行阐述,并对相关的脑成像研究进行回顾.对激素水平的研究发现,催产素能通过增加人们之间的信任来促进合作.在此基础上,介绍新近提出的关于合作的脑机制模型,最后指出这一领域已有研究存在的一些问题以及未来的研究方向.  相似文献   

19.
研究了一种存在于异性活动人群中的,通过性活动进行传播的病菌所构成的系统.在这个系统中,女性被分成N-1个不同的群体,而根据传播能力的不同,病原体菌株被分成两类.对这种系统,讨论了其地方病平衡点以及边界平衡点的稳定性,得到了这些平衡点存在及稳定的充分必要条件.结果确认,在边界平衡点的稳定性和地方病平衡点的存在性之间存在强烈的联系,即地方病平衡点存在当且仅当地方病平衡点同时存在并且具有相同的稳定性.  相似文献   

20.
Chakravarti A  Little P 《Nature》2003,421(6921):412-414
What has been learnt about individual human biology and common diseases 50 years on from the discovery of the structure of DNA? Unfortunately the double helix has not, so far, revealed as much as one would have hoped. The primary reason is an inability to determine how nurture fits into the DNA paradigm. We argue here that the environment exerts its influence at the DNA level and so will need to be understood before the underlying causal factors of common human diseases can be fully recognized.  相似文献   

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