正常人的颈部活动范围如下：屈曲35°～45°，伸展35°～45°，左右侧屈均45°，左右旋转均60°～80°。
人体端坐或站立时，从侧方看人的颈部似乎是直的，但包绕于内的颈椎并不是直的，而是在其中段有一向前凸出的弧度。这一向前的弧形凸起，在医学上称为颈椎的生理曲度。在X线片上，沿此曲度走行，在各个颈椎椎体后缘形成的连续、光滑的弧形曲线，称之为颈椎生理曲线。
颈椎生理曲线，正常值是12±5mm。其测量方法是，从齿状突后上缘开始向下，将每个椎体后缘相连成为一条弧线，然后从齿状突后上缘至第7颈椎椎体后下缘做一直线，上述弧线的最高点至这条直线的最大距离就是反映颈曲大小的数值。
2005年美国的脊柱创伤研究学组的（The spinal trauma study group, STSG)结合患者X线片、CT、MRI检查及患者的神经损伤情况提出了胸腰椎损伤评分系统（thoracolumbar injury severity score, TLISS）。TLISS主要依据3个方面：（1）基于影像学资料了解骨折的受伤机制；（2）椎体后方韧带复合结构的完整；（3）患者的神经功能状态。后来STSG改进了TLISS，把带有主观色彩的受伤机制改为更为客观的骨折形态描述，并称之为胸腰椎损伤分型及评分系统(thoracolumbar injury classification and severity score,TLICS)。具体标准是：（1）骨折的放射学形态：压缩性骨折1分，爆裂性骨折2分，旋转型骨折3分，牵张性骨折4分。若有重复，取最高分。（2）后方韧带复合体结构的完整性：完整者0分，完全断裂者3分，不完全断裂者或可疑断裂2分。（3）患者的神经功能状态：无神经损害者0分，完全性脊髓损伤者2分，不完全损伤者或马尾综合征者3分。各项分值相加即为TLICS总评分，评分越高代表损伤越严重。该分类首次综合考虑了椎体、韧带及神经功能对脊柱损伤稳定性的作用，并且量化损伤的严重程度，是具有重大意义的一次进步。
《胸腰椎损伤分类评分系统及其评价》中华外科杂志 2010 48(12)
对于胸腰椎骨折，Vaccaro等在2005年提出了TLISS评分系统，后改名为TLICS，也运用于指导临床治疗及手术决策。依据骨折形态、PLC完整性、神经症状，强调PLC在胸腰段损伤中评估和治疗的重要性。TLICS总评分≥5分，手术治疗；≤3分，非手术治疗；在两者之间手术治疗或非手术治疗。
第一种：按住ALT不放，再按0177，再放开ALT键，“±”就出来了
第二种：用 搜狗拼音 打zhengfuhao 然后选5
特朗普的计划会让政府变得愚蠢
Political leaders in most functioning democracies have established checks and laws to ensure that their countries are guided by knowledge. On 14 June, President Donald Trump took one of his biggest steps yet to dismantle an important part of this system in the United States: an executive order that federal agencies should cut the number of advisory panels by at least one-third.
This is not just another of his ill-informed policies, or one that only wonks care about. It is the government making itself stupid. Ignoring, suppressing or manipulating science advice has been a pattern of this administration; now the very committees that provide that advice are being eliminated.
Scientists must sound the alarm.
As the research director of the Center for Science and Democracy at the Union of Concerned Scientists in Washington DC, I’ve long studied the use and misuse of science in government decision-making. The federal advisory system — which includes both science and stakeholder committees — is a safeguard. It ensures that policy decisions are guided by evidence, even when there is political pressure to ignore information.
There are roughly 1,000 such committees, totalling some 60,000 members. To address issues from drug laws to foodborne illness, government agencies rely on the advice of leading specialists. Committees at the Department of Transportation make public transit safer; panels at the Department of Agriculture oversee food safety, and so on.
The Trump administration’s assault on science will have an impact far beyond this presidency. The loss of institutional knowledge, technical training and overall capacity in the government won’t simply be restored through the election of a science-friendly administration. It will take years to rebuild. Meanwhile, federal science agencies will struggle to fulfil their missions of protecting public health and safety, and the environment.
The committees now under threat also help the public to hold decision-makers accountable when they ignore important evidence. In 2008, the administration of George W. Bush — and in 2011, that of Barack Obama — failed to set a standard for ambient levels of ozone (an air pollutant that causes respiratory and cardiovascular distress) that the seven-member Clean Air Scientific Advisory Committee recommended. The recommendation enabled the public to challenge the administrations’ decisions. Without an advisory committee, the lines between science assessments and policy decisions are blurred.
The executive order is ostensibly a cost-cutting measure. But federal advisory committees are a bargain for taxpayers. Agency staff run a few meetings a year, alongside other duties, and some compensation is granted for economy-class travel and other expenses that committee members incur. According to the US Federal Advisory Committee Act Database, the Clean Air Scientific Advisory Committee spent US$951,860 in 2018, of which only $110,540 went to direct committee costs. (The rest went to existing staff members, who would have been paid anyway.) Thousands of world-class specialists donate their time to help the government to make informed decisions.
Also, every meeting of an advisory committee solicits public comments. This gives community advocates and people without easy access to government officials a way to make their views known. The upcoming cull will give the public less opportunity for input.
External advice has been one of the main targets of the Trump administration’s many attempts to sideline science. In 2017, the head of the Environmental Protection Agency (EPA) issued a directive to remove advisers with current EPA grants (individuals whose expertise the EPA clearly found useful). The agency retained advisers tied to industries that have financial interests in EPA regulations.
Our analysis found that, in the first year of the Trump administration, federal science advisory committees met less frequently than in any of the 21 years since the government started tracking them. Nearly two-thirds of these committees met less often than their charters direct. We have also logged more than 100 attacks on the use and communication of science in the Trump administration so far, more than for any other president. These include avoiding or removing terms such as ‘climate change’, halting a study by the US National Academy of Sciences and reversing a decision to ban a pesticide linked to neurological conditions in children.
Those actions have chipped away at the nation’s access to science advice. The executive order takes a jackhammer to it. By asking agencies to arbitrarily eliminate one-third of their advisory committees, the president is essentially asking which wheel you’d like removed from your car. Which is it to be: water quality, air pollution or chemical waste?
James Madison, the fourth president and a founding father of the United States, wrote, “Knowledge will forever govern ignorance; And a people who mean to be their own Governors, must arm themselves with the power which knowledge gives.” We owe it to ourselves and our expertise, to the United States and the many other nations affected by its decisions — on emissions, infectious agents, drugs and so much more — to insist on being governed by knowledge, not ignorance. Speaking up for science panels is speaking up for democracy.
So what to do? Push back, demand action. Use the power of constituency, urge Congress for oversight, and even go to court if necessary. This is not about partisan politics; it is about making decisions based on the best available information.
Nature 570, 417 (2019)
doi: 10.1038/d41586-019-01961-6
2019年SCI影响因子
一年一度的SCI影响因子发布了！2019最新SCI影响因子于2019年6月20号正式公布！详细的期刊及影响因子见附件的EXCELL文件。
关于SCI影响因子：
ISI每年出版JCR(《期刊引用报告》，全称Journal Citation Reports)。JCR对包括SCI收录的3800种核心期刊(光盘版)在内的8000多种期刊(网络版)之间的引用和被引用数据进行统计、运算，并针对每种期刊定义了影响因子(Impact Factor)等指数加以报道。一种期刊的影响因子，指的是该刊前二年发表的文献在当前年的平均被引用次数。一种刊物的影响因子越高，也即其刊载的文献被引用率越高，一方面说明这些文献报道的研究成果影响力大，另一方面也反映该刊物的学术水平高。因此，JCR以其大量的期刊统计数据及计算的影响因子等指数，而成为一种期刊评价工具。图书馆可根据JCR提供的数据制定期刊引进政策;论文作者可根据期刊的影响因子排名决定投稿方向。