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1.
【摘要】 目的 探讨低剂量DSA技术和荧光透视在经皮肝穿刺胆道引流术(PTCD)临床应用的可行性。方法 收集住院患者共86例,随机分为标准模式剂量采集组(A组,n=43)及低剂量模式采集组(B组,n=43),由科室同一医师完成PTCD手术。对两组患者手术平均指标对比分析并进行t检验。2名放射科影像医师采取盲法对所有图像进行评分。结果 两组患者均顺利完成PTCD手术,应用t检验方法,平均曝光时间[(251±16) s、(249±20) s]、图像质量评分[(3.60±0.5) s、(3.56±0.5) s],标准体重BMI[(2.81±0.25) kg/m2、(2.85±0.25) kg/m2]数值比较,P≥0.05,无统计学差异;累积剂量[(87.1±6.1) mGy、(54.4±7.7) mGy]、辐射剂量面积乘积[(2 935.2±353) μGy?cm2、(1 566.3±200) μGy?cm2]方面分析,P<0.05,差异有统计学意义。结论 采取低剂量DSA采集技术在PTCD手术患者有效可行,并且可以显著减低患者所受辐射剂量。
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2.
目的调查我院心脏介入诊疗过程中患者受照剂量分布和剂量参考水平,并分析各种剂量参数如皮肤峰值剂量(PSD)和剂量面积乘积(DAP)之间的相关性。方法对135例患者的剂量数据进行分析研究,其中接受冠状动脉造影(CAG)患者84例,接受经皮心脏介入(PCI)患者51例。记录每例患者DAP值、参考点累计剂量值(CD)以及透视时间,总采集图像幅数。采用热释光剂量片(TLD)矩阵测量患者皮肤剂量。TLD矩阵大小为10行9列,行间隔5cm,列间隔4cm。结果对于PCI,DAP均值为7946.91μGym 2 ;CD均值为1395.3mGy,平均透视时间10.9min,平均采集945幅。PSD范围为38.91~184.79mGy。DAP与PSD的相关性为0.54,PSD与CD的相关性为0.53。对于CAG,DAP均值为2690.84μGym 2 ;CD均值为431.6mGy,平均透视时间为2.9min,平均采集544幅。PSD范围26.18~120.37mGy。DAP与PSD的相关性为0.52,PSD与CD的相关性为0.45。结论患者所受皮肤剂量峰值低于所致皮肤损伤辐射阈值(2Gy)。各种辐射剂量参数(如DAP,CD和透视时间等)的结果与其他学者的研究结果相仿。从结果可以看出PSD与DAP、CD等参数相关性较差,因此基于这些数据对个体皮肤峰值剂量进行估算的方法较不科学,需要对其进一步研究。  相似文献   

3.
【摘要】 目的 探讨野战综合手术救治方舱内施行冠状动脉(冠脉)造影中不同的投照体位对患者辐射剂量和影像质量的影响,为剂量优化提出建议。方法 用标准体模测定冠脉造影9个不同投照体位下图像清晰时剂量面积乘积(DAP)和入射表面剂量(ESD)透视和摄影的辐射剂量值;并在方舱内对6只实验动物施行9个不同投照体位下的冠脉造影,观察比较不同体位的影像质量。结果 不同投照体位下,透视时DAP剂量范围值为12.96 ~ 31.28 μGym2/s, ESD透视范围为21 403.33 ~ 71 106.67 μGy/S;摄影时DAP剂量范围值为39.55 ~ 87.59 μGy/s(10帧),ESD剂量范围值为67 647.25 ~ 212 498.54 μGy(10帧)。正位剂量值最小,脾位最大,其他体位与正位相比差异均有统计学意义(P < 0.05);不同体位影像质量平均评分值范围为3.55 ~ 3.85,正位影像质量最好,脾位最差,其他体位与正位相比差异均有统计学意义(P < 0.05)。结论 不同投照体位,辐射剂量、影像质量不同。手术过程中应根据手术需要,合理选择投照体位以期既能保证图像质量又能减少患者受照剂量。

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4.
【摘要】 目的 探讨室间隔缺损(VSD)介入治疗中改良的保留导丝技术的应用价值。方法 2011年6月—2013年6月在上海长海医院行经皮VSD封堵术中应用保留导丝技术的患者62例,按操作步骤不同分成两组:传统保留导丝技术组(A组)30例和改良保留导丝技术组(B组)32例。观察两组术中封堵器的使用情况、X线透视时间、手术时间及并发症情况。结果 两组患者封堵器的使用情况及并发症发生情况比较,差异无统计学意义(P > 0.05), 两组患者均无严重并发症。A组患者术中X线透视时间为(11.96 ± 3.63)min,手术时间为(53.43 ± 14.48)min;B组患者术中X线透视时间为(9.37 ± 2.77)min,手术时间为(45.34 ± 10.38)min,两组比较,差异均有统计学意义(P < 0.05)。结论 改良保留导丝技术封堵VSD可进一步缩短X线透视时间及手术时间,且安全、有效,适合复杂性VSD的介入治疗,值得临床推广应用。

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5.
【摘要】 目的 评估经皮椎体成形术(PVP)治疗溶骨性、成骨性和混合性疼痛性脊柱转移癌的疗效、并发症及相关技术。方法 回顾性分析148例患者148个单椎体接受PVP治疗的椎体转移癌病例。根据病变椎体治疗前的CT表现,将其分为溶骨性(A组)、成骨性(B组)和混合性(C组)椎体转移癌3组。记录各组椎体术中所用透视时间、骨水泥用量及骨水泥渗漏情况。记录各组患者治疗前后的VAS评分。结果 A组86例,B组15例,C组47例患者接受了PVP治疗。A、B、C 3组有效止痛率分别为81.4%(70/86)、80.0%(12/15)和80.9%(38/47),χ2 = 0.019,P = 0.991、P > 0.05。3组每个椎体的平均透视时间分别为(8.5 ± 1.9)min、(14.4 ± 2.5)min和(8.3 ± 1.7)min,经方差分析F = 63.073、P = 0.000;个椎体骨水泥用量分别为(3.36 ± 0.96)ml、(2.60 ± 0.89)ml和(3.23 ± 0.94)ml,F = 4.126,P = 0.018、P < 0.05;骨水泥渗漏率分别为27.9%(24/86)、20.0%(3/15)、25.5%(12/47),χ2 = 0.435,P = 0.804、P > 0.05。结论 PVP治疗不同类型椎体转移癌的止痛效果满意,并发症少。但其在成骨性病变的治疗中操作技术相对复杂,需注意穿刺技巧并控制骨水泥用量。

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6.
【摘要】 目的 探讨心血管病介入诊疗中的X线电离辐射对心血管病患者DNA损伤的影响。方法 收治接受心血管病介入诊疗患者244例,按介入术式不同分为四组:经皮冠状动脉造影术组87例,经皮冠状动脉介入术组72例,射频消融术组48例,起搏器植入术组37例。分别于术前、术后2 h、 24 h抽取患者外周血,检测外周血淋巴细胞染色体微核。同时记录患者手术全程辐射的累积皮肤表面入射剂量(CD)、面积剂量乘积(DAP)、透视时间(FT)等,观察各种介入诊疗中患者接受的辐射损伤程度和差异。结果 经皮冠状动脉支架置入术组CD和DAP值显著高于其他三组,而其他三组间CD和DAP值差异无统计学意义(P > 0.05)。患者术后2 h染色体微核率为16.3‰ ± 4.2‰,P < 0.05),术后24 h为17.5‰ ± 5.1‰,,明显高于术前水平(13.8‰ ± 4.7‰,P < 0.05)。结论 不同介入术中,患者接受的辐射剂量不同,但介入诊疗中的电离辐射都可能会造成患者的DNA损伤。
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7.
【摘要】 目的 分析心血管疾病患者在介入诊疗过程中的辐射剂量,探讨其预防措施。方法 抽取用SIEMENS Aritis Zee Floor DSA 介入诊疗的心血管疾病患者186例,记录随机配备的辐射检测系统显示的总辐射时间(T)、剂量面积乘积(DAP)、累积剂量(CD),由DAP估算有效剂量(ED),由CD估算最高皮肤剂量值(PSD)。结果 患者所受T为0.9 ~ 71.2 min,平均10.5 min,> 30 min的9例(4.8%); ED为0.11 ~ 282.9 mSv,平均32.2 mSv,> 100 mSv的10例(5.4%);1 Gy < PSD(1/2CD) ≤ 3 Gy的40例(21.5%),PSD(1/2CD) > 3 Gy的4例(2.2%);1 Gy < PSD(4/5CD) ≤ 3 Gy的53例(28.5%),PSD(4/5CD) > 3 Gy的14例(7.5%)。T与PSD(1/2 CD)、PSD(4/5CD)、ED在置信度(双侧)为0.01时显著相关。结论23.7% ~ 36.0%心血管介入患者可因累积剂量导致严重的皮肤损伤,5.4%心血管介入患者有显著的致癌危险。
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8.
目的 研究子宫肌瘤患者在子宫动脉栓塞(UAE)术中所经受的X射线照射及降低辐射的方法.方法 回顾性分析早期90例和近期10例UAE辐射剂量资料,采用DSA机(Angiostar Plus)配置的穿透电离室型剂量监测系统(Diamentor KI和Diamentor ED),在线读取面积剂量乘积(DAP)(cGy·cm2)和入射表面剂量(ESD)(mGy).结果 早期90例UAE透视时间(28.60±23.73)min,摄影(87±38)帧,DAP均值(6 178±3 802)cGy·cm2,ESD均值(3  相似文献   

9.
【摘要】 目的 探讨三维标测结合房间隔穿剌入路消融左侧旁道(LAP)的优势。方法 回顾性分析2012年1月至2018年1月经心内电生理检查诊断为LAP并接受射频消融治疗的106例阵发性室上性心动过速患者临床资料。根据标测和消融途径不同将患者分为房间隔穿刺入路组(A组)和主动脉逆行入路组(B组),比较两组LAP位置分布、手术时间、X线曝光时间、放电时间、手术成功率及并发症。结果A、B组间LAP位置分布、手术时间、放电时间、手术成功率及并发症比较,差异均无统计学意义(P>0.05);A组术中X线曝光时间显著短于B组[(4.1±1.9) min对(18.1±10.5) min,P<0.001]。结论 三维标测结合房间隔穿剌入路射频消融LAP安全有效,X线透视时间显著缩短,有望成为三维电生理时代LAP消融常规术式。

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10.
【摘要】 目的 探讨用次高温热球囊及冷冻球囊处理动脉狭窄模型的可行性及最佳效果参数。方法 取动脉粥样硬化性狭窄动物模型,采用热球囊及冷冻球囊扩张髂内动脉粥样硬化狭窄段。将符合研究条件的实验对象(6头长白猪)分为A组(热球囊,42 ~ 50℃,扩张10 min)、B组(热球囊,42 ~ 50℃,扩张20 min)和C组(冷冻球囊,-10℃,扩张2 min),每组2头。DSA下导入球囊至血管狭窄段,在X线透视下,向球囊注入载热液体或氧化亚氮介质扩张球囊,同时用高灵敏温度测量仪实时测量球囊局部靶血管壁所承受的热、冷负荷。血管成形术后4周行病理学检查,动物处死前均行血管造影。观察局部血管对次高温、浅低温的反应及演变过程。结果 A、B、C组的血管横断面积分别为(263 653.76 ±251 422.46)μm2、(348 123.68 ± 199 871.47)μm2和(260 960.68 ± 141 244.12)μm2,B组大于A组和C组(P = 0.003 7);每高倍镜视野内膜平滑肌细胞数目及管腔狭窄指数分别为(289 ± 34)个和0.49 ± 0.18、(330 ± 105)个和0.78 ± 0.17、(232 ± 66)个和0.57 ± 0.19,B组亦高于A组和C组(P = 0.000 1);中膜面积及内膜面积分别为(545 198.09 ± 64 574.07)μm2和(178 497.16 ± 83 903.75)μm2、(543 880.64 ± 66 129.98)μm2和(84 640.09 ± 55 330.06)μm2、(640 743.85 ± 262 858.74)μm2和(263 897.40 ± 268 037.66)μm2,C组大于A组和B组(P = 0.000 1);内膜/中膜面积比(代表内膜增生程度)及内膜增生指数分别为0.34 ± 0.19和0.25 ± 0.11、0.16 ± 0.10和0.13 ± 0.07、0.42 ± 0.50和0.24 ± 0.19,B组低于A组和C组(P = 0.000 1)。结论 局部导入“次高温”或“浅低温”均可抑制平滑肌细胞增殖、移行和分泌基质,从而可能会降低血管成形术后远期再狭窄率,最佳效果参数为次高温42 ~ 50℃,扩张时间20 min。

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11.
Lithium borohydride, a well known complex hydride with its high hydrogen capacity, has shown its application as a solid electrolyte for Li-ion battery. It has been employed as a solid electrolyte with Bi2Te3 nanosheets as anode material for lithium-ion batteries (LIBs). The Bi2Te3 nanosheets were synthesized by the solvothermal method with an average crystallite size of 55 nm as calculated by Debye Scherrer formula. The scanning electron microscopy (SEM), and transmission electron microscopy (TEM) experiments reveal the morphology of the prepared sample as hexagonal nanosheets with the thickness in the range of 20–40 nm. Initial discharge and charge capacity of the negative electrode is found to be 555 mAhg−1 & 1290 mAhg−1 using galvanostatic charge-discharge analyzer at a rate of 0.1C. During the electrochemical charging-discharging experiment, strange but interesting gas evolution was observed, which resulted in the opening of the cell. The careful investigation of this reaction using TG/MS suggest the destabilization of LiBH4. The thermal dehydrogenation analysis depicts that the LiBH4–Bi2Te3 nanosheets composite starts to desorb hydrogen at 61 °C with a total of 9% weight loss. The above destabilization is investigated using XRD and XPS experiments and the detailed mechanism is proposed herein.  相似文献   

12.
物流仓储促进了经济的发展熏但是同时也给环境带来负面的影响熏如大量燃料和能源在物流过程中被消耗。文章介绍了上海大众汽车有限公司如何通过对化学品及燃料的物流管理方式的优化,在实现降低物流成本的同时实现能耗的降低。  相似文献   

13.
We demonstrate that zein-jute fiber composites developed using water plasticized zein as matrix can have substantially higher flexural and tensile properties than composites obtained using polypropylene as matrix. Zein is a plant protein that has been used to develop various types of thermoplastic products. Zein can be extracted from corn distillers dried grains (DDG) with potentially much lower cost than biopolymers in current use. However, thermoplastics developed from zein are brittle and it is necessary to use plasticizers or chemically modify zein to obtain useful zein-based products. Hydrophilic plasticizers such as glycerol that are retained in the composite after fabrication absorb moisture and considerably decrease the properties of the composites. Similarly, chemical modifications make the matrix materials expensive and/or decrease their biodegradability. In this research, we have used water to plasticize zein composites reinforced with jute fibers. Unlike plasticizers such as glycerol, water used as a plasticizer in this research evaporates during composite formation and does not affect the properties of the composites. Zein-jute composites have about 100% higher flexural strength, 82% higher tensile strength than similar PP-jute composites. The zein-jute composites have better flexural and tensile properties than PP-jute composites even at 21 °C and 90% relative humidity. Water serves as an effective plasticizer to utilize zein as a matrix for composites.  相似文献   

14.
Hydrogen, used as fuel, has a number of attractive features that make it a leading candidate in the search for an alternative to the dwindling and progressively less reliable supply of fluid hydrocarbon fuels. Hydrogen produced by electrolysis using hydro- or nuclear-generated electricity will be available in Canada at prices competitive with other portable forms of energy before the end of the century. This paper examines the use of carbon-free electrolytic hydrogen as a motor vehicle fuel and as a fuel for fuel cells. A review of onboard hydrogen storage systems indicates that the propulsion power unit of hydrogen-fueled vehicles must be considerably more efficient than present gasoline-fueled internal combustion engines in order to compensate for the larger size and greater weight of hydrogen storage systems. Hydrogen-fueled internal combustion engines are more efficient than similar gasoline-fueled engines, but the improvement is not sufficient to offset the storage system limitation. Fuel cells operate with much higher efficiency than internal combustion engines, especially at partial loads. A comparison between H3PO4 and KOH fuel cells show that where carbon-free hydrogen is available from the onboard storage system, the KOH fuel cell offers the higher level of performance.  相似文献   

15.
应该注意电力体制改革中可能出现的问题   总被引:2,自引:0,他引:2  
我国电力体制改革方案已经国务院批准.厂网分开,电网方面成立国家电网公司和南方电网,电源方面成立若干个发电公司竞价上网.今后输电和销售还将分开,按照市场经济规则运行.中央的决策,我们一定坚决贯彻.  相似文献   

16.
Recent pertinent legislation concerning the handling, recycling and/or disposal of domestic, municipal and industrial refuse in the UK is reviewed. At present it appears that UK energy policy is being influenced significantly by EC environmental legislation. Nevertheless, an overall strategy for dealing with garbage is needed urgently.  相似文献   

17.
本文分析了我国农用车及与之配套的柴油发动机的现状、行业结构和产品存在的问题与差距,分析了技术的发展趋势,加入WTO后发展的机遇与挑战,应对WTO可采取的措施.我国加入WTO为农用车提供了更加巨大的国内外市场,农用车行业在新的机遇和挑战中向更大、更强和国际化方向发展.  相似文献   

18.
Hydrogen is emerging as one of the most promising energy carriers for the future. Most of the methodologies used for hydrogen production employ use of hydrogenases, known to play a critical role in biological hydrogen production as well as its utilization. These hydrogenases display fascinating redox-chemical properties with tremendous efficiency as a biocatalyst for hydrogen fuel. However, Due to the complex structure and maturation process of hydrogenases, their heterologous production has been a challenging task. This results in the limitation of the viable application of this metalloprotein for hydrogen fuel. This review briefly discusses various hydrogenase expression systems and their perspectives.  相似文献   

19.
It is my long-held belief that hydrogen has a possibility of becoming a substitute for coal gas as well as other industrial gases and, because of its special properties, it should replace coal gas in the future. On this occasion I express my view on the subject and would welcome your comments. I may have used somewhat insufficient data and may have introduced some dreamy points in the lecture. The suggested usage of hydrogen as fuel gas is not my original idea; since a French scientist, E. Viel, advocated the idea in 1868, similar discussions have been made from time to time.  相似文献   

20.
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