当我平躺在手推车上,视野里只有天花板那么一小片地方,而那一块地方,毫无色彩,以此为参照,似乎你一直就没有动过。周围也变得静寂,从病房到电梯,平时几步就走过去的路程,似乎也走了很久。 我突然意识到,我到底是不是癌其实已经确定了,这一刀切下去,答案就完全公开了,而之前所做的种种推想,科学的,或者不科学学的,科学的,比方穿刺,比方钼靶,比方核磁共振;不科学的,比方从医生的神态,语气等等进行的判断,那种从网上所查找的病例,朋友们为安慰我而说的种种虚惊,甚至那种神秘的预感等等等等,而我从这些林林总总中所推测的好的结论,都会在此面前不堪一击,近一个月来的种种挣扎都毫无意义,就如同面对一个无可避免的失败,想起我们曾经为了挽回这个结局曾经所做过的种种徒劳的挣扎,我们会感到多么的痛心,无望和无助......而我基于良好的愿望基础上所做的种种假设,在事实面前,又是如此无力!想到此,一滴清泪从眼角溢出,流过太阳穴,滴到了手推车上,接着,有一滴......医生俯下身来,轻声问一句,紧张了?一会麻药一打,你就像睡着一样,醒来手术就做好了。 我其实不紧张,我只是做好了准备,准备接受一直被我掩盖着的事实。那天是6月5日,我最后一天可以不把自己作为癌症病人,尽管当时我是,或许已经是了很久了。无论如何,此刻,在心理上,我还在癌的这边,和大多数人一样,可以尽享平常的好处,可以抗争,可以奋斗,可以无所顾忌,而做了手术,我可能就到那一边了,Cancer has a way of issuing patients a sudden ticket to the world of otherness。 手术室没有腾出来,我被推到墙角,有几个医护人员在哪儿谈笑风生,所有有关病情的种种,似乎丝毫没有影响到他们的情绪;另一个手推车被推到我身边,手推车上的是个男人,和我并行着躺着,有点同床共枕的感觉,问他什么问题,他说他打呼,大概是晚上想和爱人睡在一起,又不至于影响爱人睡眠的贴心丈夫。而我那种生死攸关的感觉,在这个空间里格格不入,我应该也只是在此一游的过客,所等待着的,不是那个决定生死的手术,而是看个风景,解个风情。然后,走向新的彼岸...... 当我被推到手术室,推我进来的人告诉里面的人说,病人有点紧张,一群小姑娘便叽叽喳喳地把我从手推车上扶到麻醉台上,脱我的衣服,吩咐我伸开手臂,一个很和善的小姑娘把一个塑料罩子放到我鼻子上,说让我数一二三,数到十,如果想睡觉就睡。我很听话地数着,没有到十,我就失去知觉了。 等我醒来,一个人告诉我手术已经做完,其间发生的种种事情,我毫无感觉,这段时间,我把生命的支配权让渡给了大夫。按照医生先前的告知,我知道其间有好几根管子从我的嘴里插到心肺等处,以便于维持我最基本的生命体征。而这些我都一无所知,脑子里唯一的概念是:我是否是癌症?等医生把我折腾到病床上,我命令老公看看我的腋窝有伤口没有? 老公说有纱布包着,看不到。他不敢扯开看,可能有伤口,否则干嘛要包纱布。而我还在挣扎着要那么一个希望,希望那里没有伤口,这样,当我手术刀口愈合,我就可以回家,重新开始生活了。第二天,医生撤了氧气瓶之类的,把我的护理也从一级护理改为二级,我以为这可能是医生们给的信号,起码证明我的病情不是很重,就大着胆子问那个和他谈手术问题的医生:我不是癌吧? “是癌,是浸润癌,都已经不是原位癌了。” 这些天为了证明我不是癌而恶补的有关肿瘤学知识,恰好让我知道,癌在我的身体里已经完成了它的整个演变过程,正准备蚕食我的生命呢。那天无意间从乳房下面那么一抹,手指就触摸到一个肿块,而这个肿块,竟然就是那个能把我小命要走的癌!那天是5月10日,晚上,有点热,坐在电脑跟前,我把衣服解开了,手下意识地从下往上滑过,感觉乳房下面有点硬,当时便有点不详的预感,而终于,预感成真,而这,也太让人不可思议了:死亡,就这么触手可及么?
美国纽约大学、纽约州立大学石溪分校和英国剑桥大学的研究人员开发出基于核磁共振成像(MRI)方法的锂电池内部检测技术,可为电池内部运作提供诊断服务,提高电池性能和安全性。相关研究成果发表在《自然—材料学》上。 锂电池充电时,锂纤维会附着在锂电池内部的碳电极上,会导致电池短路、过热着火,甚至爆炸。研究人员可利用该方法扫描分析锂电池内部的化学成分,消除隐患。。 核磁共振成像技术属于非侵入性技术,可以提供电池内部的微观结构,可视化电极表面上的微小变化。电解质和电极表面都可以使用这种可视化技术,提供了全面了解电池性能的变化进程。研究人员将进一步研究高清晰成像、成像时间更短的技术和方法,最终使电池更轻、更安全、更灵活。 该方法还可用于研究材料表面的不规则行为和裂缝,还可评估其他电化学设备,如燃料电池。该研究得到了美国能源部和美国国家科学基金会的资助。 7 Li MRI of Li batteries reveals location of microstructural lithium There is an ever-increasing need for advanced batteries for portable electronics, to power electric vehicles and to facilitate the distribution and storage of energy derived from renewable energy sources The increasing demands on batteries and other electrochemical devices have spurred research into the development of new electrode materials that could lead to better performance and lower cost (increased capacity, stability and cycle life, and safety). These developments have, in turn, given rise to a vigorous search for the development of robust and reliable diagnostic tools to monitor and analyse battery performance, where possible,in situ. Yet, a proven, convenient and non-invasive technology, with an ability to image in three dimensions the chemical changes that occur inside a full battery as it cycles, has yet to emerge. Here we demonstrate techniques based on magnetic resonance imaging, which enable a completely non-invasive visualization and characterization of the changes that occur on battery electrodes and in the electrolyte. The current application focuses on lithium-metal batteries and the observation of electrode microstructure build-up as a result of charging. The methods developed here will be highly valuable in the quest for enhanced battery performance and in the evaluation of other electrochemical devices. http://www.nature.com/nmat/journal/v11/n4/full/nmat3246.html#affil-auth
The lipoprotein subfraction profile: heritability and identification of quantitative trait loci Abstract The HDL and LDL subclass profile is an emerging cardiovascular risk factor. Yet, the biological and genetic mechanisms controlling the lipoprotein subclass distribution are unclear. Therefore, we aimed 1) to determine the heritability of the entire spectrum of LDL and HDL subclass features and 2) to identify gene loci influencing the lipoprotein subfraction pattern. Using NMR spectroscopy, we analyzed the lipoprotein subclass distribution in 1,275 coronary artery disease patients derived from the Regensburg Myocardial Infarction Family Study. We calculated heritabilities, performed a microsatellite genome scan, and calculated linkage. HDL and LDL subclass profiles showed heritabilities ranging from 23% to 67% (all P 10(-3)) of traits using univariate calculation. After multivariate adjustment, we found heritabilities of 27-48% (all P 0.05) for HDL and 21-44% for LDL traits. The linkage analysis revealed a significant logarithm of the odds (LOD) score (3.3) for HDL particle concentration on chromosome 18 and a highly suggestive signal for HDL particle size on chromosome 12 (2.9). After multivariate adjustment, we found a significant maximum LOD score of 3.7 for HDL size. Our study is the first to analyze heritability and linkage for the entire spectrum of LDL and HDL subclass features. Our findings may lead to the identification of genes controlling the lipoprotein subclass distribution.
催化基础国家重点实验室纳米和界面催化研究组(502组)受邀撰写的综述文章“In situ solid-state NMR for heterogeneous catalysis: a joint experimental and theoretical approach”在近期出版的Chemical Society Reviews上发表(Chem. Soc. Rev., 2012, 41, 192-210),影响因子26.585。 文章综述了近十年来该研究组利用原位固体核磁共振技术在多相催化领域取得的重要进展。文章介绍了原位固体核磁共振方法及其在酸性表征、催化反应机理和反应动力学中的应用,强调了实验结合理论计算在确定反应中间体结构及反应机理研究中的重要作用。 近年来,该研究组致力于发展原位固体核磁共振方法以及核磁共振信号灵敏度增强技术,在催化反应及材料表征领域取得了一些重要成果。例如,与美国西北太平洋国家实验室合作,利用高场95Mo NMR(21.1 Tesla)研究了甲烷芳构化反应中碳化钼活性物种。相关结果发表在《美国化学会志》(J. Am. Chem. Soc., 130(2008)3722-3723);在自行研制的一套与固体核磁共振仪耦合的动态催化反应系统中,采用激光诱导超极化129Xe技术,首次在模拟催化反应条件下直接观察到了甲醇分子在孔径为0.8nm的CHA分子筛孔道扩散和脱水过程,并精确获得了分子扩散和反应的动力学参数。相关方法和实验结果以研究论文形式(Article)发表在《美国化学会志》(J. Am. Chem. Soc., 131(2009)13722-13727),被认为是“一种对纳米孔催化反应研究具有重要意义”的发明。 此外,该研究组一直致力于基础催化与应用催化的结合。与低碳烃综合利用及沸石催化材料研究组(DNL0804组)合作利用固体核磁共振技术深入研究了烯烃歧化反应以及共结晶分子筛的结构。相关工作分别发表在J. Catal.,J. Phys. Chem. C等刊物。与甲烷及低碳烃转化新催化过程研究组(DNL0802组)合作在离子液合成分子筛领域也取得了重要进展,相关工作发表在Chem. Eur. J., Phys. Chem. Chem. Phys.等刊物。 In situ solid-state NMR for heterogeneous catalysis: a joint experimental and theoretical approach Weiping Zhang, Shutao Xu, Xiuwen Han and Xinhe Bao Chem. Soc. Rev., 2012, 41, 192-210 DOI: 10.1039/C1CS15009J Received 10 Jan 2011, First published on the web 11 Jul 2011 Abstract In situ solid-state NMR is a well-established tool for investigations of the structures of the adsorbed reactants, intermediates and products on the surface of solid catalysts. The techniques allow identifications of both the active sites such as acidic sites and reaction processes after introduction of adsorbates and reactants inside an NMR rotor under magic angle spinning (MAS). The in situ solid-state NMR studies of the reactions can be achieved in two ways, i.e. under batch-like or continuous-flow conditions. The former technique is low cost and accessible to the commercial instrument while the latter one is close to the real catalytic reactions on the solids. This critical review describes the research progress on the in situ solid-state NMR techniques and the applications in heterogeneous catalysis under batch-like and continuous-flow conditions in recent years. Some typical probe molecules are summarized here to detect the Brønsted and Lewis acidic sites by MAS NMR. The catalytic reactions discussed in this review include methane aromatization, olefin selective oxidation and olefin metathesis on the metal oxide-containing zeolites. With combining the in situ MAS NMR spectroscopy and the density functional theoretical (DFT) calculations, the intermediates on the catalyst can be identified, and the reaction mechanism is revealed. Reaction kinetic analysis in the nanospace instead of in the bulk state can also be performed by employing laser-enhanced MAS NMR techniques in the in situ flow mode (163 references). http://pubs.rsc.org/en/Content/ArticleLanding/2012/CS/c1cs15009j