甲型H1N1流感与气象因子的关系及预报模型研究

目的研究气象条件的变化对甲型H1N1流感活动强度的影响,建立气象因子对甲型H1N1流感阳性检出率的预报模型。方法收集浙江省2009年4月—2011年1月甲型H1N1流感疫情资料、各哨点医院的监测资料以及同期气象资料,在采用Spearman相关分析甲型H1N1流感活动强度与有关气象因子的相关关系的基础上,通过卡方自动交互检测方法建立决策树预报模型。结果甲型H1N1流感阳性检出率与周平均气压（r=0.50）、最高气压（r=0.51）、降水量（r=-0.23）、最低气压（r=0.50）、平均气温（r=-0.40）、最高气温（r=-0.41）、最低气温（r=-0.39）、平均风速（r=-0.22）、气温周较差（r=-0.30）和周平均温差（r=-0.30）等气象因子存在相关性（P〈0.05）。影响甲型H1N1流感阳性检出率的主要气象因子为最低气压、平均风速和降水量（P均〈0.05）。将甲型H1N1流感阳性检出率分为不同等级与气象因子建立预报模型,模型预测的正确率为66.67%。结论最低气压、平均风速、降水量等气象因子与甲型H1N1流感活动强度密切相关,可利用决策树建立模型作预测预报。     

一种便携式应急甲状腺辐射监测仪的研制

目的 为满足放射性事故情况下的应急准备和响应的要求,需要对相关人员进行甲状腺的辐射测量,快速估算人员受照射剂量,尽快确定污染水平及核素种类以便进行相应处理。方法 本文研制了一种便携式的甲状腺辐射监测仪,用于应急状态下实现快速医学响应。本文利用蒙特卡罗方法模拟计算了不同尺寸NaI晶体的探测效率;并重点考虑了轻便性和可移动性的功能设计。本文还开发了甲状腺剂量评价软件,实现对放射性碘的摄入量和待积剂量当量的准确估算。结果 设备实现稳定可靠运行,其中能量分辨率为7%（662 keV时）,探测下限小于15 Bq（对于¹³¹I）,探测速度达到每小时不小于20人,总重30 kg,满足轻便、可快速移动的要求。结论 在核事故情况下,设备能快速运送到事故现场,满足应急救援队伍现场开展甲状腺的辐射监测和评估的要求,填补了技术空白。     

Automatic detection of erosions and ulcerations in wireless capsule endoscopy images based on a deep convolutional neural network

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PHILIPS DR常见故障分析与处理

本文讨论了有关PHILIPS DR的常见故障,通过对该设备的工作原理和故障的现象进行分析,多角度提出造成故障各种可能的原因,一一进行分析,提出排除和解决问题的方法,并通过实践加以证明其准确性。该文还着重论述了PHILIPS DR设备正确的使用方法及设备维修人员如何做好保养及预防性维修等方法,以减少机器的突发性故障,延长使用寿命,为从事PHILIPS DR维修工作的同行提供参考。     

Development and validation of a RP-HPLC method for the determination of gentamicin sulfate and its related substances in a pharmaceutical cream using a short pentafluorophenyl column and a Charged Aerosol Detector

Gentamicin sulfate is a potent broad spectrum aminoglycoside antibiotic which is used as an active pharmaceutical ingredient (API) against both Gram-positive and Gram-negative bacteria. A reversed-phase high performance liquid chromatographic (RP-HPLC) method has been developed and validated to determine the composition of gentamicin sulfate and to estimate its related substances (without any pre- or post-column derivatization) in a pharmaceutical cream. As gentamicin has a weak UV chromophore, it is not possible to detect low levels of known and unknown related substances of gentamicin using a UV detector. In this method, a Charged Aerosol Detector (CAD) was used to obtain high sensitivity that was necessary for the intended purpose of the method. This method can separate all the analogues of gentamicin including all known and unknown related substances of the API. A short (5 cm × 4.6 mm) pentafluorophenyl HPLC column from Restek (Allure PFP) was used with an ion-pair gradient mobile phase consisting of (A) heptafluorobutyric acid:water:acetonitrile (0.025:95:5, v/v/v) and (B) trifluoroacetic acid:water:acetonitrile (1:95:5, v/v/v).     

A simple inexpensive device for monitoring patient respiration

A simple device is described that monitors respiration by sounding an alarm if respiration ceases. It is light and portable and performs well, even in a 60dB noise environment.     

计算机X线摄影与直接数字X线摄影在胸部摄影中的应用比较

目的目的比较计算机X线摄影（CR）与直接数字X线摄影（DR）两种成像方式在胸部摄影中的临床应用,以求对实际工作提供帮助。方法抽取胸部影像CR1000例,DR1000例。从应用范围、摄影方式、X线的剂量、成像时间、图像质量、图像的调节与处理等方面将两者进行比较。结果 DR对于胸部影像的甲级片率为70.2%,摄影速度为60人/h;CR的甲级片率为57.4%,摄影速度为30人/h。结论 DR在成像质量、甲级片率等方面优于CR,但两者各有其优缺点。     

A methodology for dosimetry audit of rotational radiotherapy using a commercial detector array

Purpose

To develop a methodology for the use of a commercial detector array in dosimetry audits of rotational radiotherapy.

Materials and methods

The methodology was developed as part of the development of a national audit of rotational radiotherapy. Ten cancer centres were asked to create a rotational radiotherapy treatment plan for a three-dimensional treatment-planning-system (3DTPS) test and audited. Phantom measurements using a commercial 2D ionisation chamber (IC) array were compared with measurements using 0.125 cm³ IC, Gafchromic film and alanine pellets in the same plane. Relative and absolute gamma index (γ) comparisons were made for Gafchromic film and 2D-Array planes, respectively.

Results

Comparisons between individual detectors within the 2D-Array against the corresponding IC and alanine measurement showed a statistically significant concordance correlation coefficient (both ρ_c > 0.998, p < 0.001) with mean difference of −1.1 ± 1.1% and −0.8 ± 1.1%, respectively, in a high dose PTV. In the γ comparison between the 2D-Array and film it was that the 2D-Array was more likely to fail planes where there was a dose discrepancy due to the absolute analysis performed.

Conclusions

It has been found that using a commercial detector array for a dosimetry audit of rotational radiotherapy is suitable in place of standard systems of dosimetry.     

Lightspeed型16排CT常见故障维修方法的研究与应用

目的:通过掌握Lightspeed型16排CT的常见故障诊断及快速维修的方法,提升维修人员的专业技术水平,达到快速排除Lightspeed型16排CT的常见故障的目的。方法:通过学习、培训,掌握16排CT的系统结构和工作原理。积累16排CT常见故障的维修经验,总结出简易可行的维修方法。结果:利用简易可行的维修方法可快速处理Lightspeed型16排CT的常见故障,减少了设备的停机时间,延长了设备的使用寿命。结论:快速维修方法维修Lightspeed型16排CT,可有效排除16排CT的常见故障,延长设备的使用寿命,降低医院经营成本。