医用X射线机电磁兼容测试中的问题及其分析

目的随着科学技术的发展,国内外对电磁兼容的重视度越来越高。在检测工作中发现大多数X射线机电磁兼容不合格,其原因大都是出于厂方在设计产品时没有进行合理的抑制设计。本文旨在总结不合格项目的整改办法。方法本文通过X射线机静电放电、射频电磁场辐射等抗扰度实验项目,重点分析了X射线机的电磁干扰产生机理及传播方式,并提出通用的整改思路及措施。结果在X射线机各部件的电磁兼容项目整改过程中,通常可采用增加外壳屏蔽、加强接地、更换屏蔽线材等措施对产品进行优化,从而加强其抗干扰性。而其中PCB电路板整改难度最大,需在前期研发过程中重点设计。结论本文对医用X射线机电磁兼容测试中出现的问题深入分析后设计了一套X射线机电磁兼容不合格项目的基本整改流程,帮助企业有效解决常见问题,缩短研发周期,降低研发与物料成本,提升产品质量。     

基于LabVIEW的X射线机电源电阻测量设计

目的:为降低测量仪器系统误差噪声干扰的影响，准确测量X射线机电源电阻，设计一套X射线机电源电阻测量程序。方法:在信号注入法测电阻的基础上，利用LabVIEW软件和NI公司生产的信号调理模块，设计电源内阻测量程序，该程序可产生稳定的正弦激励电流，并对响应电压、响应电流以及相位差进行测量，进而得到X射线机电源电阻值。结果:经系统测试可知，该测量程序可以对X射线机电源电阻进行一段时间内的连续测量，得到的电源电阻均值更接近实际状况。结论:该测量程序能够准确测量X射线机电源电阻，为准确测量X射线机电源电阻提供了一种新的方法和思路。 【关键词】X射线机；电源电阻；LabVIEW     

基于非线性估计的CBCT几何标定算法

针对传统的几何标定算法由标定模体位姿误差导致的CBCT成像系统参数标定精度不高的问题,提出一种基于解析几何和非线性优化的CBCT几何标定算法。首先,设计一种插帧追踪的方法,提取特征点的坐标,使得标定模体与投影图像中的特征点实现一一对应。然后,利用投影图片与设计的标定模体之间的空间几何关系,计算相关参数。最后,对检测的特征点进行非线性估计,进一步提高几何参数的计算精度。仿真数据实验表明,本文算法能够较为精确地计算出CBCT成像系统的几何参数,并在标定模体出现位姿偏差时仍然保持较高的计算精度。通过非线性估计模型,本文所提出的算法突破了现有算法标定模体位于等中心点的限制,提高了CBCT成像系统中参数标定的精度。     

GE AMX-4Plus移动X射线机的数字化X射线摄影改造

目的为了提高床旁X射线摄片的图像质量,对现有移动X射线机GEAMX-4Plus进行数字化X射线摄影（DR）改造,由原来影像板（IP）成像再行计算机X射线摄影（CR）扫描获得图像的方式改为DR直接摄片。方法以移动X射线机为基础．配置Pixium3543无线平板系统．设计基于该平板的数字摄影操作平台系统和曝光同步控制系统。结果DR改造后,移动X射线机可以正常使用,性能稳定,图像质量较以前CR模式得到大幅提高,获得临床认可。结论数字化x射线摄影改造既使原有移动X射线机得到充分的利用,也使床旁摄片质量、临床诊断及时性、准确度等方面得到大幅提高。     

药理学实验中生物医学信号采集方式设计的探讨

本文介绍了药理学实验中 ,四种数据采集方式的设计 ,以及实验信号的标定 ,采样 ,实验参数的标度变换的实现。     

移动式C型臂X射线机图像拼接在骨科手术中的应用

背景：在脊柱和长骨骨折等骨科手术治疗中,获取骨折部位的完整骨结构图像对于监控和评价骨科术中效果具有十分重要的临床意义。 目的：探讨移动式C型臂X射线机图像拼接技术在临床骨科手术中的应用效果。 方法：对骨科手术部位的脊柱和长骨进行C型臂X射线机透视并采集2-4幅图像,经过图像拼接软件将图像多区域重叠,进行图像拼接技术处理后得到脊柱和长骨骨折内固定手术部位的1张全景图像。 结果与结论：移动式C型臂X射线机图像拼接技术处理后能在1张照片上获得脊柱和长骨骨折内固定手术部位全景图像,能较清晰、完整地显示脊柱和长骨的全景,并有助于术者在术中及时地了解和评估骨折部位的对位、对线情况,且能进行长度和角度测量,为进一步提高手术质量提供强有力的支持。     

咖啡因再处理对X射线诱发的离体人血淋巴细胞染色体畸变的影响

本文研究了:(a)咖啡因处理对X线照射的G_2期淋巴细胞的影响:(b)在G_1、S、G_2期时给与咖啡因的影响;(c)咖啡因对X射线诱发的辐射敏感综合征患者(Down综合征和毛细管扩张性运动失调症)淋巴细胞染色体畸变的影响。实验分为7组,从Caff Ⅰ到Caff Ⅶ。除了Caff Ⅱa外,都用Ham′s F-10培养基,辐射     

2D-3D医学图像配准临床数据集标定结果的分析与评价

目的 构建采自临床的2D-3D医学图像配准数据集,是实现各种学习算法应用于实际医疗的重要环节。然而临床数据的获取过程中存在多种不确定因素,致使数据集的标定结果需要分析和评价。本文对采自胸主动脉腔内修复术的一组X线和CT图像的几组标定数据进行分析和评价,并确定正确标定结果。方法 分别采用相似性度量法和投影距离误差法对标定结果进行分析和评价。选用相似性准则,计算CT图像生成的二维数字放射重建图像和X线图像的相似性,相似程度越高,对应的标定值越接近真实值。读取X线图像中的标记物影像位置作为参考位置;将计算得到的CT图像中标记物位置在X线图像上投影,得到投影位置;计算参考位置和投影位置的距离,距离值越小,对应的标定值越接近真实值。结果 提供的几组标定数据,在比较数字放射重建图像和X线图像相似性方面,相似度接近,没有明显指向性;而投影距离误差法的分析结果指向性明显,能够定量描述标定结果的优劣。主要原因在于各组标定值之间差别不突出;生成的数字放射重建图像和X线图像之间模态差异较大等。结论 投影距离误差法是评价2D-3D医学图像配准数据集标定结果的有效手段。另外,若提供的标定结果计算数据差异明显,或...     

移位股骨颈头下骨折模拟C臂X射线机观察闭合复位的真实精确性

背景：采用牵引床C臂X射线机下闭合复位、内固定治疗股骨颈头下骨折,可能有一定的误差。 目的：模拟C臂X射线机下闭合复位透视分析骨折闭合复位的真实精确性。 方法：直视下完全复位人工骨股骨颈头下骨折标本,使用克氏针固定。在股骨颈外侧,两个断端处分别使用克氏针打入,作为金属标志物。保持股骨颈标本、C臂X射线机位置不动,随后将股骨头分别顺时针、逆时针旋转15°,30°,再分别使用C臂机透视标准股骨颈正侧位,使用图像采集电脑工作站,采集图像。 结果与结论：在股骨颈顺时针旋转15°、逆时针旋转15°时,股骨颈头下骨折两端皮质在正侧位透视下的移位差异无显著性意义,都有1 mm左右移位。在股骨颈顺时针旋转30°、逆时针旋转30°时,股骨颈两端皮质在正侧位透视下的移位差异无显著性意义,都有2 mm左右移位。表明使用C臂X射线机观察移位的股骨颈头下骨折,满足Garden指数复位要求,但不能判断出股骨头有无旋转,治疗移位的股骨颈头下骨折要切开复位。 关键词：股骨颈;骨折;切开复位;闭合复位;数字化图像与影像 doi:10.3969/j.issn.1673-8225.2012.09.029     

基于IMU的C形臂旋转角度定位方法的研究

目的移动式X线透视影像设备(C形臂)凭借其便携、实时的优势已成为图像引导手术中标准配置设备,然而大部分医院配备的C形臂不具备旋转角度测量功能。方法本文设计了一种基于惯性测量单元的C形臂旋转运动角度定位方法。通过融合惯性测量单元中各惯性测量器件的实时测量数据,构建世界坐标系和载体坐标系的旋转矩阵,利用四元数分量求解C形臂旋转角度,从而对C形臂旋转运动进行定位。本文设计了精密电动旋转平台标定实验和C形臂旋转定位实验对本文方法进行了评估。结果在精密电动旋转平台标定实验中,本文设计方法的最大定位误差为0.5°;在C形臂的实验中,最大定位误差为0.8°,能够满足临床手术导航需求(定位误差不大于1°)。结论本文设计的定位方法不需要标定和校正过程,流程简单易行,具有很强的适应性,能够为后续手术导航提供必要的角度信息。     

The universal muscular chain reaction,muscle spasm,Torsions, ruptures and extravasations. Chameleons of pathology and some manifestations of simple muscular disorders

Most bodily functions require the coordinated actions of complementary and supplementary paired muscle groups. Where this essential muscular cooperation is lacking, hollow organs may burst and others become literally screwed up, giving rise to many similar spastic diseases such as Torticollis, Twisted ovarian cyst, Torsion of the Testis, Volvulus of the intestines, Varicose Veins, Megacolon, Aortamegaly, Scoliosis, Erb's Palsy, Peyronie's Disease, Main-en-Griffe, Undescended Foot (Pes Cavus), Talipes, Strabismus. Spasm is “panenepidemic” and unclassified examples of Torsion Dystonia and Dyskinesia really are as common as debt and taxes.     

Studien zur humoralen Regulation des erythropoetischen Proliferationsspeichers beim Menschen

Zusammenfassung Die Beeinflussung der Erythroblasten-Proliferation durch das Mikromilieu wurde in vitro mittels Auswertung durch Differential- und Mitosezählungen und Signifikanzberechnung vieler Versuchsreihen auch unter verschiedenen pathologischen Bedingungen getestet.Sowohl die Mitosehäufigkeit wie die Ausreifung waren positiv mit dem Erythropoetingehalt des Medium korreliert. Der Effekt wurde durch Folsäure, Ätiocholanolon und cAMP verstärkt. Cobalt stimulierte ebenso wie Testosteron und Methenolon in vitro unabhängig von der Erythropoetinkonzentration im Medium die Erythroblastenproliferation. Ein vermindertes Eisenangebot störte die endgültige Ausreifung der Erythroblasten zu Retikulozyten und bewirkte dadurch eine Ineffektivität der Erythorpoese. Anhaltspunkte für ein Erythrozyten-Chalon oder einen Erythropoetinhemmkörper ließen sich aus unserem Versuchsansatz nicht gewinnen, weil er die Transformation der pluripotenten in die erythropoetin-sensible Stammzelle nicht einschließt. Als Nebenbefund ergab sich eine Stimulation des granulozytopoetischen Proliferationsspeichers durch Serumzusatz zum Medium von Patienten nach akutem Blutverlust und bei Polycythämia vera.Unterstützt durch die Deutsche Forschungsgemeinschaft     

HLA study in Amerindian Bolivia La Paz Aymaras

Aymara people has been a relatively homogeneous group since Spanish Conquest by 1,532 CE, even if previously represented a group of various cultural defined populations who gave rise to them. They were and are established in Andean Altiplano around Titikaka Lake (Bolivia, Peru), Argentina and Chile neighborhood, speak Aymara language and have been maintained after Europeans arrival at a lower social status than Quechua (Inca) speaking people. However, both Aymara and Quechua populations acknowledge Titikaka Lake as center of their origins; both languages are also related. Specific high frequencies of HLA-A*02, -A*24 and -A*68, HLA-B*35, -B*39 and -B*48, HLA-DRB1*08:02, -DRB1*09:01, and -DRB1*14:02, and HLA-DQB1*04:02, -DQB1*03:02 and -DQB1*03:01 alleles are found in Aymaras and HLA class II haplotypes common to Andean Amerindians (DRB1*08:02-DQB1*04:02 and DRB1*04:03-DQB1*03:02), like Quechua, Aymara, Uros, Lamas and Mapuche are also found in Easter and other Pacific Islands. Giant human head stone statues at Tiwanaku (Titikaka Lake, Bolivia) are also found at Easter Island. Thus, it is possible a gene and cultural flow between Andean Amerindians and Easter and other Pacific Islands, as it was demonstrated by Thor Heyerdahl in his Kon-Tiki expedition which reached Pacific Islands sailing from El Callao Harbour (Lima, Peru).     

Hypo- und Hypermagnesämie aus kardiologischer Sicht

Zusammenfassung Eine Reihe pathologischer Zustände bedingen Magnesiummangel. Zustände mit Hypermagnesämie sind ebenfalls bekannt, doch wesentlich seltener. Für den Kardiologen beachtenswert ist, daß unter Therapie mit bestimmten Diuretica bei Herzinsuffizienz, bei Herzinfarkt, Kardiomyopathie, Digitalisintoxikation und bestimmten Herzrhythmusstörungen Hypomagnesämie beobachtet wurde. Leider kann in der klinischen Routine nur ein extracelluläres Magnesiumdefizit durch Serumbestimmungen gemessen werden; über Magnesiummangel einzelner Organe kann nichts ausgesagt werden. Hinweise für Magnesiummangel geben aber neben der Messung des Serumspiegels Anamnese, klinischer Befund, bestimmte EKG-Veränderungen wie auch evtl. Hypokalämie, ein Zustand, bei dem sich oft — besonders bei Aldosteronismus — parallele Veränderungen zeigten.Tierexperimente deuten darauf hin, daß infarktähnliche Läsionen unter Magnesiummangel entstehen, doch ob Herzinfarkt beim Menschen durch Magnesiummangel ausgelöst werden kann, ist noch ungeklärt. In Leichenherzen zeigte sich im Infarktgebiet neben Calciumakkumulation signifikanter Magnesiumverlust, wobei unklar blieb, ob sich Ursache oder Folge des Infarktes widerspiegelten. Falls ein ursächlicher Zusammenhang besteht, ist er im Myokardstoffwechsel selbst zu suchen, wie bei der Alkoholkardiomyopathie, wo myokardialer Magnesiummangel zumindest als pathogenetischer Teilfaktor anerkannt wird. Andererseits versucht man aber auch Beziehungen zwischen Atherosklerose, Blutgerinnung und Hypomagnesämie herzustellen, in der Meinung, daß Magnesiummangel auch über den coronaren Pathomechanismus des Herzinfarktes wirken könnte. Sicher scheint, daß gewisse EKG-Veränderungen und Herzrhythmusstörungen durch einen irritierten Magnesiumhaushalt bedingt sein können, da sie bei Gabe bzw. Entzug von Magnesium verschwinden. Daß Magnesiummangel die Glykosidtoleranz verringert, wird tierexperimentell bestätigt. Unter Hypomagnesämie bewirkt Acetylstrophanthidin eher und länger Rhythmusstörungen als ohne, außerdem lassen diese sich durch Magnesiumgaben eliminieren. Da in gewissen Fällen spontane und digitalisinduzierte Herzrythmusstörungen durch Magnesiuminjektionen beseitigt wurden, scheint Magnesium als Therapeuticum angebracht. Einsatz verschiedener Magnesiumsalze bei Angina pectoris, degenerativen Herzerkrankungen und Herzinsuffizienz ohne geprüften und offensichtlich gestörten Magnesiumhaushalt ist fragwürdig, weil keine eindeutigen klinischen Erfolgsbeweise vorliegen. Immerhin mag es aber larvierte, durch Serumbestimmungen nicht erfaßbare Mangelzustände geben. Allgemein erscheint es aus kardiologischer Sicht ratsam, den Magnesiumhaushalt zu überwachen und in entsprechenden Fällen auszugleichen, um möglichen Myokardläsionen oder fatalen Herzrhythmusstörungen entgegenzuwirken.     

Lipid composition of metacestodes of Taenia taeniaeformis and lipid changes during growth

A lipid analysis was performed on developing metacestodes of Taenia taeniaeformis removed from the livers of rats at times varying from 3 to 35 weeks post infection. Lipid accounted for 7–21% of the dry weight of the parasites. The highest proportions were found at the earlier stages. The distribution was as follows; neutral lipid 27–45%; glycolipid 5–11%; and phospholipid 50–61%. The major neutral lipid was cholesterol, and minor neutral lipids were sterol esters, triglycerides, diglycerides and monoglycerides. Hydrocarbons were present throughout development, but in the highest amounts at the earlier stages. Five different glycolipids were found, all of which were identified as glycosphingolipids. An increase in the proportion of more complex glycolipids was noted as parasites grew older. Ten different phospholipids were identified, with the major components being phosphatidylcholine, phosphatidylethanolamine, and phosphatidylserine. Other phospholipids were: lysophosphatides, phosphatidylinositol, phosphatidic acid, diphosphatidylglycerol, sphingomyelin, and an unknown phospholipid component. Changes in the relative amounts of the two major phospholipids were found when the early and late stages were compared. Two lipids found throughout development were identified as glycosylated dolichol phosphates, and they comprised between 1 and 3% of the total phospholipid fraction. Nineteen fatty acids were detected, and the fatty acid distribution for each lipid class at each stage was determined. Seven major fatty acids were common to each. These were: hexadecanoic, octadecanoic, oleic, linoleic, arachidonic, docosanoic, and docosahexaenoic.     

Environmental risk factors and their role in the management of atopic dermatitis

Introduction: The etiology of atopic dermatitis (AD) is multifactorial with interaction between genetics, immune and environmental factors.

Areas covered: We review the role of prenatal exposures, irritants and pruritogens, pathogens, climate factors, including temperature, humidity, ultraviolet radiation, outdoor and indoor air pollutants, tobacco smoke exposure, water hardness, urban vs. rural living, diet, breastfeeding, probiotics and prebiotics on AD.

Expert commentary: The increased global prevalence of AD cannot be attributed to genetics alone, suggesting that evolving environmental exposures may trigger and/or flare disease in predisposed individuals. There is a complex interplay between different environmental factors, including individual use of personal care products and exposure to climate, pollution, food and other exogenous factors. Understanding these complex risk factors is crucial to developing targeted interventions to prevent the disease in millions. Moreover, patients require counseling on optimal regimens for minimization of exposure to irritants and pruritogens and other harmful exposures.     

Simple Serological Assays for Detecting Rice Tungro Viruses

An attempt was made to produce sensitive and specific polyclonal antisera against the viruses causing rice tungro disease, and to assess their potential for use in simple diagnostic tests. Using a multiple, sequential injection procedure, seven batches of polyclonal antisera against rice tungro bacilliform virus (RTBV) and rice tungro spherical virus (RTSV) were produced. These were characterized for their sensitivity and specificity using ring-interface precipitin test and double antibody sandwich (DAS) ELISA. Thirty-one weeks after the first immunization, antiserum batch B6b for RTBV showed the highest ring interface titer (DEP = 1:1920). For RTSV, batches S3, S4b and S5b all had similar titres (DEP = 1:640). In DAS-ELISA, however, significant differences among purified antisera (IgG) batches were observed only at IgG dilution of 10^-3. At that dilution, IgGB4b showed the greatest sensitivity, while IgGS3 showed greatest sensitivity for RTSV. When all IgG batches were tested against 11 tungro field isolates (dual RTBV-RTSV infections) at sample dilution of 1:10, IgGB4b and IgGB6b for RTBV and IgGS3 and IgGS6b for RTSV performed equally well. However, after cross adsorption with healthy plant extracts in a specially prepared healthy plant-Sepharose affinity column, only IgGB6b could be used specifically to detect RTBV in a simple tissue-print assay.     

Is it worthy to take full-course immunotherapy for allergic rhinitis? About efficacy biomarker of allergen immunotherapy

Nowadays, people pay more attention to biomarkers that can predict clinical efficacy of immunotherapy for allergic rhinitis. As the only recognized aetiological treatment, the efficacy of allergen immunotherapy (AIT) has been proved by many studies. However, treatment success depends on compliance and persistence greatly, which can be impaired by the lengthy duration of AIT and socioeconomic status of patients. Besides, ineffectiveness is another factor that accounts for non-adherence. If the clinical efficacy can be predicted in the early stage of immunotherapy, it can help patients choose appropriate treatment plans, increase patient compliance and optimize the allocation of medical resources. This paper mainly focuses on five candidate biomarkers, the sIgE/tIgE ratio before treatment, serum inhibitory activity for IgE, decreased basophil activation, upregulation of Tregs and tolerogenic DCs, reviews the time when potential biomarkers can predict or monitor the efficacy of AIT, discusses the reason why these indicators could serve as efficacy biomarkers and interactions among potential biomarkers.     

Neurotransmitter signaling pathways required for normal development in Xenopus laevis embryos: a pharmacological survey screen

Neurotransmitters are not only involved in brain function but are also important signaling molecules for many diverse cell types. Neurotransmitters are widely conserved, from evolutionarily ancient organisms lacking nervous systems through man. Here, results are reported from a loss‐ and gain‐of‐function survey, using pharmacological modulators of several neurotransmitter pathways to examine possible roles for these pathways in normal embryogenesis. Applying reagents targeting the glutamatergic, adrenergic and dopaminergic pathways to embryos of Xenopus laevis from gastrulation to organogenesis stages, we observed and quantified numerous malformations, including craniofacial defects, hyperpigmentation, muscle mispatterning and miscoiling of the gut. These data implicate several key neurotransmitters in new embryonic patterning roles, reveal novel earlier stages for processes involved in eye development, suggest new targets for subsequent molecular‐genetic investigation, and highlight the necessity for in‐depth toxicology studies of psychoactive compounds to which human embryos might be exposed during pregnancy.     

HLA genes in Amerindians from Mexico San Vicente Tancuayalab Teenek/Huastecos

Huastecos or Teenek Amerindians are presently living at North East Mexico (San Luis Potosi State). They have probably one of the most ancient culture of Mexico and Central America together with Mayas and Olmec groups with which also show close relationships. Proximity to Atlantic Ocean/Mexican Gulf originated that Spaniards had very early contact with them at about 1519 CE or before. In the present paper we have aimed to study HLA gene profile which may be useful for HLA and disease epidemiology and transplant programs in Teeneks. HLA-DRB1*04:07, -DRB1*14:06 and -DRB1*04:11 have been found in high frequency like in other Amerindian groups. High frequency typical Amerindians HLA extended haplotypes have been found, such as A*02-B*35-DRB1*04:07-DQB1*03:02; A*68-B*39-DRB1*04:07-DQB1*03:02 and A*02-B*39-DRB1*04:07-DQB1*03:02; also new haplotypes have been described, like A*02-B*52-DRB1*04:11-DQB1*03:02, A*68-B*35-DRB1*14:02-DQB1*03:01 and A*68-B*40-DRB1*16:02-DQB1*03:01. Genetic proximity is observed not only to linguistically close Mayans, but also to Mazatecans, Mixtecans and Zapotecans, who speak an altogether different languages; it shows once more that genes and languages do not correlate. This population was greatly diminished after European contact between 1500 and 1600 years CE; in fact, North and South America First Inhabitants population was brought from 80 down to 8 million people because of diseases (i.e.: measles, smallpox or influenza), slavery and war.