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1.
Long‐term expansion of human induced pluripotent stem cells in a microcarrier‐based dynamic system 下载免费PDF全文
2.
我们非常感激你对儿音响产品的关心,并且希望它能成为你家庭音响和家庭影院中的一部分。
当我们进入家庭音响市场的时候,我们公司承诺会以性能和品质的最高标准来创造产品。我们相信你会从Fathom@或者Gofham中的每个细节中看到儿音响对品质的承诺,但最重要的是,我们相信你会在每次欣赏电影和享受音乐的时候都会感受得到。 相似文献
3.
AV Kabashin Ph Delaporte A Pereira D Grojo R Torres Th Sarnet M Sentis 《Nanoscale research letters》2010,5(3):454-463
An overview of pulsed laser-assisted methods for nanofabrication, which are currently developed in our Institute (LP3), is
presented. The methods compass a variety of possibilities for material nanostructuring offered by laser–matter interactions
and imply either the nanostructuring of the laser-illuminated surface itself, as in cases of direct laser ablation or laser
plasma-assisted treatment of semiconductors to form light-absorbing and light-emitting nano-architectures, as well as periodic
nanoarrays, or laser-assisted production of nanoclusters and their controlled growth in gaseous or liquid medium to form nanostructured
films or colloidal nanoparticles. Nanomaterials synthesized by laser-assisted methods have a variety of unique properties,
not reproducible by any other route, and are of importance for photovoltaics, optoelectronics, biological sensing, imaging
and therapeutics. 相似文献
4.
Emad. M. Elsehly N. G. Chechenin A. V. Makunin H. A. Motaweh E. A. Vorobyeva K. A. Bukunov E. G. Leksina A. B. Priselkova 《中国化学工程学报》2016,24(12):1695-1702
Filtration efficiency of Ni(II) from aqueous solution using pristine and modified MWCNTs filters was investigated as a function of Ni(II) ion concentration, pH, and filter mass. MWCNTs were synthesized by CVD method and modified using two complementary treatments, purification (using a mixture of hydrochloric acid and hydrogen peroxide) and functionalization (using nitric acid). The effect and mechanism of each treatment on the structural integrity of pristine MWCNTs has been studied. Morphology of the pristine and modified filters was investigated by Raman Spectrometry (RS), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), Fourier Transform Infrared (FTIR) spectrometry and Thermogravimetric analysis. It was found from Raman spec-tra that the ratio of the intensity of D-band to that of G-band decreased by purification process, and increased by functionalization process. The adsorption mechanism of Ni(II) onto the surface functional groups of modified MWCNTs was confirmed by FTIR spectrum. The filtration results showed that the removal efficiency of Ni(II) is strongly dependent on pH and could reach 85%at pH=8. Also, modified MWCNT filters can be reused through many cycles of regeneration with high performance. Functionalized MWCNTs filters may be a promising adsor-bent candidate for heavy metal removal from wastewater. 相似文献
5.
Authors on behalf of ICRP FA Stewart AV Akleyev M Hauer-Jensen JH Hendry NJ Kleiman TJ Macvittie BM Aleman AB Edgar K Mabuchi CR Muirhead RE Shore WH Wallace 《Annals of the ICRP》2012,41(1-2):1-322
This report provides a review of early and late effects of radiation in normal tissues and organs with respect to radiation protection. It was instigated following a recommendation in Publication 103 (ICRP, 2007), and it provides updated estimates of 'practical' threshold doses for tissue injury defined at the level of 1% incidence. Estimates are given for morbidity and mortality endpoints in all organ systems following acute, fractionated, or chronic exposure. The organ systems comprise the haematopoietic, immune, reproductive, circulatory, respiratory, musculoskeletal, endocrine, and nervous systems; the digestive and urinary tracts; the skin; and the eye. Particular attention is paid to circulatory disease and cataracts because of recent evidence of higher incidences of injury than expected after lower doses; hence, threshold doses appear to be lower than previously considered. This is largely because of the increasing incidences with increasing times after exposure. In the context of protection, it is the threshold doses for very long follow-up times that are the most relevant for workers and the public; for example, the atomic bomb survivors with 40-50years of follow-up. Radiotherapy data generally apply for shorter follow-up times because of competing causes of death in cancer patients, and hence the risks of radiation-induced circulatory disease at those earlier times are lower. A variety of biological response modifiers have been used to help reduce late reactions in many tissues. These include antioxidants, radical scavengers, inhibitors of apoptosis, anti-inflammatory drugs, angiotensin-converting enzyme inhibitors, growth factors, and cytokines. In many cases, these give dose modification factors of 1.1-1.2, and in a few cases 1.5-2, indicating the potential for increasing threshold doses in known exposure cases. In contrast, there are agents that enhance radiation responses, notably other cytotoxic agents such as antimetabolites, alkylating agents, anti-angiogenic drugs, and antibiotics, as well as genetic and comorbidity factors. Most tissues show a sparing effect of dose fractionation, so that total doses for a given endpoint are higher if the dose is fractionated rather than when given as a single dose. However, for reactions manifesting very late after low total doses, particularly for cataracts and circulatory disease, it appears that the rate of dose delivery does not modify the low incidence. This implies that the injury in these cases and at these low dose levels is caused by single-hit irreparable-type events. For these two tissues, a threshold dose of 0.5Gy is proposed herein for practical purposes, irrespective of the rate of dose delivery, and future studies may elucidate this judgement further. 相似文献
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TM Gerhardt GE Schmahl C Flotho AV Rath CM Niemeyer 《Canadian Metallurgical Quarterly》1997,99(4):882-887
Activation of the Evi-1 gene was first described to be associated with the transformation of murine myeloid leukaemias and has previously been detected in cases of human acute myeloid leukaemia (AML) and chronic myeloid leukaemia (CML) in blast crises and in myelodysplastic syndromes. In this study we determined the frequency and the level of Evi-1 expression in juvenile myelomonocytic leukaemia (JMML) and in normal haemopoiesis. Using RT-PCR and Southern blot hybridization mRNA of Evi-1 could be detected in bone marrow (BM) and peripheral blood (PB) mononuclear cells (MNC) of normal donors. In JMML 12/20 patients examined expressed elevated levels of Evi-1 compared to normal controls. In these samples over-expression of the gene was correlated with a higher percentage of blasts (P = 0.02). Expression levels in BFU-E and CFU-GM derived colonies from BM of JMML patients were lower than those in the corresponding MNC samples. Analysis of CD34+ and CD34- cells demonstrated that Evi-1 is primarily expressed in the CD34+ cell population of both JMML and normal donors. These findings suggest that Evi-1 expression is linked to the early stages of haemopoiesis. Studies on the regulation of Evi-1 expression in CD34+ cells will elucidate its function in progenitor cells and clarify its possible role in the pathogenesis of JMML. 相似文献