等中心

方法：在等中心摆位技术基础上，根据直线加速器治疗床的水平纵向、横向、垂直上下移动时计算机提供实时移床的精确数据，使每次照射两相邻野中心距离不变；

Methods : On the basis of isocenter replacement technique , digital display replacement technique can provide a constant distance of two neighboring field centers by using the computer-provided precise real-time couch shifting data , which respond to line couchs in horizontal , longitudinal , transverse and vertical shifting directions .

X刀系统等中心的验证和调整方法

A method of the verification and adjustment of X-knife system 's isocenter

X刀系统等中心精度检测方法

A Method for Measuring the Isocentre Positional Accuracy of X Knife System

本文介绍一种测量X刀系统机械等中心定位精度的方法，即胶片同心圆法。

In this paper , a film concentric circle method for measuring the mechanical isocentre positional accuracy is introduced .

在X刀的治疗过程中，系统的机械等中心定位精度是一个关键性的技术参数。

The mechanical isocentre positional accuracy of the X Knife system is a very important technological parameter in the course of the X Knife therpy .

在检查的不同机器臂架/治疗床角度中机械等中心最大误差为（1.0±0.6）mm；

The maximal error of the mechanical isocenter was ( 1.0 ± 0.6 ) mm according to the different mechanical gantry / table angles .

进入迷宫巷道后，X射线剂量当量率一般不超过等中心有用束X射线吸收剂量率的10－6。

The dose equivalent rates in tunnel of the maze are less than 10-6 of the absorbed dose rate from the useful beam at the isocenter .

Cox回归分析等中心数和肿瘤体积对肿瘤控制有显著影响，而适形指数对生存期有显著影响。

Isocenter numbers and tumor volume were the prognostic factors for tumor control , but conformity index was prognostic factor for survival as determined by Cox regression analysis .

过去10年，在伦敦与纽约等中心，IPO市场一直处于垂死状态。因此，机构投资者已几乎只交易二手股票，而不是向成长中的企业提供新资金。

For the past 10 years , in centres such as London and New York , the new issue market has been moribund , and so institutional investors almost exclusively trade second-hand shares , rather than providing fresh capital for growing businesses .

方法：采用X线立体定向技术，单次、大剂量照射脑转移瘤，设4个~9个非共面照射野，80%等中心剂量线覆盖PTV。

Methods Brain metastases of all patients were radiated with high-dose X-rays stereotactic radiosurgery ( SRS ) only one fraction , which including 4 to 9 non-coplane fields and whose PTV were enveloped 80 % iso-center dose .

三维激光定位系统是CT-SIM定位系统的标定等中心点的执行装置，它通过在人体体表上投射出三个标记点来完成对肿瘤等中心点的标记任务。

Three-dimensional laser positioning system is the actuator of CT-SIM positioning system , which is used for calibrating the isocenter point . The three markers are projected out on the body surface to accomplish the task of marking the isocenter point of tumor .

B20正推动各方在全球增长乏力等中心议题上采取有效行动，促使各国做出切实承诺，以解决大盈余国（如中国和德国）与赤字国家（如美国和许多欧洲国家）之间的结构性失衡。

It is pushing for effective action on the central issue of flagging global growth , framing concrete commitments from individual countries to address structural imbalances between big surplus countries , such as China and Germany , and deficit nations , such as the US and many European states .

乳腺癌等中心照射定位技术的改进

The Improvement on the Technique of Breast Cancer Isocenter Irradiation Orientation

用等中心四分之一野结合虚拟楔形板照射技术治疗乳腺癌

Combined mono-isocentric quarter portal and virtual wedge irradiation technique for breast carcinoma

低熔点铅不规则挡块等中心治疗在鼻咽癌放疗中的应用

Radiotherapy with Low-Melting-Point Lead Irregular Shield for Nasopharyngeal Carcinoma

固定束质子治疗病人摆位系统的精确性评估：等中心旋转运动

The Accuracy Assessment of PPS in Fixed Beam Proton Therapy : Isocentric Rotation Movement

目的介绍颈段肿瘤等中心定位与治疗技术。

Objective To introduce the isocentric localization and treatment technology used in cervical tumor .

方法：用立体定向等中心直线加速器放射外科治疗226例颅内各种疾病。

Methods : We had treated 226 patients of intracranial lesions using X knife radiosurgery .

目的：寻找一种简单明了的乳腺切线野等中心定位方法。

Objective : To seek a easy and perspicuous method for fixing the galactophore ISO tangent field .

如果考虑到肿瘤恶性程度，只有等中心数和肿瘤体积对肿瘤控制时间有显著影响。

Considered of pathology , only isocenter number and target volume significantly affected the tumor control interval .

结论等中心旋转是实现固定束质子等中心多角度照射的关键运动模式。

Conclusion The isocentric rotation movement is the linchpin to realize multi-angle isocentric irradiation in fixed beam proton therapy .

本文通过对放疗模拟定位机的等中心回转误差分析，提出了一些对策措施。实践证明，这些方法是行之有效的。

This article-analyzes isocenter rotation resolution of radiotherapy simulator and puts forward technical methods that have been proved in practice .

例如，在北京和上海、武汉等中心城市之间开有夕发朝至列车，带有舒适的卧铺车厢。

There are overnight trains with comfortable sleeper cabins running between Beijing and central cities such as Shanghai and Wuhan , for example .

我们可以看到，艺术家在文艺复兴之后纷纷从乡村迁往伦敦、巴黎、罗马和柏林等中心城市。

We can watch as artists flock from rural areas to urban centers like London , Paris , Rome and Berlin after the Renaissance .

为了标定等中心位置，一般使用激光定位机指示。

In order to demarcate the mark of the iso-center , it is common to use the laser positioning device to indicate the iso-center .

方法：观察加速器等中心精度，灯光野，激光定位灯改变对摆位精度的影响。

Methods : To observe the conrealtion between the position accuracy and the accuracy of isocenter , lamp field , targeted field , laser lamp .

结论：SRS200机械等中心精度均已达到立体定向放射外科治疗的质量控制要求。

Conclusion : All results indicate that the accuracy of this mechanical isocenter subsystem had come up to the standard of quality control of X-knife .

方法根据等中心旋转切线照射的物理原理，使用PinnacleVersion7.4的子野优化软件做治疗计划。

Methods Based on the physical principle of rolling tangential technique , a treatment plan for a patient has been planned by using Pinnacle aperture-based inversion software .

在几乎每个前线阵地港口、电力、公路、机场以及孟买等中心城市的市区交通基础设施都已接近崩溃边缘。

On almost every front - ports , electricity , roads , airports and urban transport in centres such as Mumbai - infrastructure is close to breaking point .

其中56例采用常规固定源皮距照射方法治疗，41例采用改进的低熔点铅挡块等中心技术。

Of them , fifty-six patients were treated with conventional radiotherapeutic technique ( fixed source-skin-distance ) and 41 with the improved technique ( cerrobend block facio-cervical portal and isocenter ) .