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1.
目的:比较静态和动态调强放疗(IMRT)计划在直肠癌放疗过程中剂量的准确性。方法选取我院12例直肠癌动态IMRT计划和12例直肠癌静态IMRT计划,采用二维电离室矩阵对其进行点剂量和面剂量的验证。结果参照3%/3 mm标准,动态IMRT计划24个照射野以及静态IMRT计划24个照射野的面剂量的γ通过率均值分别为99.2%和97.6%,二者比较差异有统计学意义(P<0.05)。动态和静态IMRT计划点剂量的误差均值分别为1.8%和3.1%,二者比较差异有统计学意义(P<0.05)。结论在加速器正常运行状态下,静态和动态IMRT计划都可以应用于直肠癌调强放射治疗,但在验证剂量精确性上,动态IMRT计划优于静态IMRT计划。  相似文献   

2.
目的:通过比较胶片与二维电离室矩阵应用于调强放射治疗个体化患者剂量分布的验证结果,研究使用二维电离室矩阵进行调强放疗验证的可行性.方法:用IBA OmniPro IMRT 1.5软件对胶片与二维电离室矩阵MATRIXX采集的射野剂量数据进行分析处理.结果:通过比较胶片与二维电离室矩阵对射野剂量分布的验证结果,分析得知二维电离室矩阵应用于调强放疗计划进行验证确实可行.结论:使用二维电离室矩阵进行调强放疗个体化患者剂量验证,方法切实有效,简单可行,建立了便捷可靠的调强放疗剂量验证体系.  相似文献   

3.
目的:探讨二维电离室矩阵探测器Detector729剂量测量的准确性及其在放射治疗质量控制中的应用。方法:采用0.6 cm3的参考电离室在X射线下对Detector729进行剂量刻度,然后两者进行剂量和输出因子测量比对,最后应用Detector729对调强放射治疗(intensity modulated radiation therapy,IMRT)治疗计划进行实际机架角剂量验证。结果:参考电离室对Detec-tor729电离室的刻度因子是0.991,两者测量结果比对相对测量偏差≤ 0.57%,在4 cm×4 cm~ 20 cm×20 cm不同方形野下输出因子测量结果基本一致,应用Detector729对IMRT剂量验证的γ通过率均>90%。结论:应用Detector729进行放疗剂量测量和质量控制工作,结果具有较高的准确度和可信度,可为规范我国放疗剂量测量工具的使用提供理论依据。  相似文献   

4.
目的:通过比较调强放疗剂量验证的结果,评价Monaco和Xio治疗计划系统的临床治疗准确性。方法选取Xio治疗计划系统20例鼻咽癌调强治疗计划,Monaco治疗计划系统20例鼻咽癌调强治疗计划,用IBA二维电离室矩阵Matrixx进行剂量验证,分别以2%/2 mm、3%/3 mm、5%/3 mm为标准进行Gamma通过率分析。结果 Monaco系统在3种标准下的Gamma平均通过率均高于Xio系统。差异在2%/2 mm、3%/3 mm下具有统计学意义(P〈0.05),5%/3 mm下无统计学意义(P>0.05)。结论两种治疗计划系统都能应用于临床调强放疗,但Monaco计划系统的准确性要优于Xio计划系统。  相似文献   

5.
目的探讨二维Mapcheck在调强放疗剂量验证中的作用。方法随机抽取20例鼻咽癌患者,进行cT定位扫描,然后把图像传输至核通三维逆向治疗计划系统,并设计出均分野(七野)治疗计划。利用固体水模板在治疗计划系统中建立三维等效模体,将待验证的IMRT计划套于模体内,分别计算出每野在模体中的剂量分布,选取模体中感兴趣平面上的每野剂量分布,传输至MAPCHECK验证软件系统,在加速器下进行二维剂量模拟照射并与计划系统计算的结果相比较,验证相对剂量和绝对剂量。结果采用DTA方法,剂量位置限定在3%/3mm标准条件下,所有射野中相对量的通过率在97%之间,绝对量的平均通过率在95%之间, mapcheck验证结果与计划值相似,误差率小于电离室。结论剂量学验证是IMRT临床实施的可靠保证,使用MAPCHECK分析软件进行剂量验证具有适时、方便、快捷的特点,免去了胶片验证法中冲洗、扫描胶片的过程,也减少了大部分的系统误差。因此,MAPCHECK分析软件如今已成为剂量验证的常规工具。  相似文献   

6.
目的 探讨逆向调强适形放疗(IMRT)的剂量学验证方法,保证接受治疗患者剂量的准确性.方法 随机抽取30例鼻咽癌患者,进行CT定位扫描,然后把图像传输至核通PLATO三维逆向治疗计划系统,并设计出均分野(七野)治疗计划.利用固体水模板在治疗计划系统中建立三维等效模体,将待验证的IMRT计划套于模体内,分别计算出每野在模体中的剂量分布,选取模体中感兴趣平面上的每野剂量分布,传输至MAPCHECK验证软件系统,在加速器下进行二维剂量模拟照射并与计划系统计算的结果相比较,验证相对剂量和绝对剂量.结果 采用DTA方法,剂量位置限定在3%/3mm标准条件下,所有射野中相对量的通过率在85%~100%之间,绝对量的平均通过率在80.7%~100%之间.结论 剂量学验证是IMRT临床实施的可靠保证,使用MAPCHECK分析软件进行剂量验证具有适时、方便、快捷的特点,免去了胶片验证法中冲洗、扫描胶片的过程,也减少了大部分的系统误差.因此,MAPCHECK分析软件如今已成为我院剂量验证的常规工具.  相似文献   

7.
目的利用PTW二维矩阵及配套八角均匀模体对调强放射治疗(IMRT)计划进行剂量验证,通过对比分析找出能更真实反映剂量准确性的剂量验证方法。方法随机选取53例患者的IMRT计划,分别进行单角度调强验证测量和多角度调强验证测量,对两种方法的测量结果用γ通过率分析方法(3%3 mm标准)进行比较分析。结果在53例患者计划中,均采用统一标准进行剂量验证,根据肿瘤部位分别验证,其中头颈部、胸部、腹部+盆腔其γ分析通过率:多角度调强验证γ通过率(98.7±1.3)%、(95.8±8.7)%、(98.1±2.9)%,单角度调强验证γ通过率(99.4±0.8)%、(98.9±1.9)%、(99.1±1.5)%;总患者数其γ分析通过率:多角度调强验证γ通过率(97.6±5.1)%,单角度调强验证γ通过率(99.2±1.4)%。结论由于多角度调强验证方法考虑了加速器及多叶准直器在不同机架角度时对输出剂量的影响,同时减少了多野叠加时剂量误差的相互抵消的趋向,它的验证条件与临床实际治疗计划条件相互一致,测量得到的剂量分布能更真实地反映实际情况。因此多角度调强验证更值得推广和使用。  相似文献   

8.
调强放疗个体化患者剂量验证   总被引:3,自引:0,他引:3  
目的:建立调强放疗个体化患者剂量验证体系。方法:IBA公司的0.65型电离室配合相应剂量仪DOSE1及验证模体进行绝对剂量的验证;二维电离室矩阵MATRIXX进行相对剂量的验证。结果:利用电离室在选定的参考点进行绝对剂量的验证,以此为基础,使用二维电离室矩阵进行相对剂量的验证,可以得出患者调强放疗计划执行的误差。结论:该方法切实有效,简单可行,建立了调强放疗个体化患者剂量验证体系。  相似文献   

9.
目的探讨逆向调强适形放疗(IMRT)的剂量学验证方法,建立适合临床要求的评价标准。方法随机抽取30例头颈部肿瘤患者,进行CT定位扫描,然后把图像传输至Pinnacle逆向治疗计划系统,并设计出均分野(5-9野)治疗计划。利用固体水在治疗计划系统中建立三维等效模体,将待验证的IMRT计划移植到模体内,分别计算出每野在模体中的剂量分布并传输至MAPCHECK验证软件系统。在加速器下进行模拟照射并与计划系统计算的平面剂量相比较,采用DTA和Gamma方法,限定在3%/3 mm,10%标准条件下验证相对剂量和绝对剂量的通过率,并采用SPSS 16.0统计软件进行配对t检验。结果所有射野中Gamma方法相对量的通过率在(94.2±2.6)%,绝对量的平均通过率在(93.2±2.1)%;DTA方法相对量的通过率在(92.1±3.3)%,绝对量的平均通过率在(90.6±2.8)%。两种方法的通过率存在显著差异。结论调强验证中不同评价方法验证结果受多种因素影响,相应的临床价值需要进一步研究,以确保医疗质量。  相似文献   

10.
目的 探讨建立调强放疗个体化患者剂量的验证体系.方法 使用IBA公司生产的0.65型电离室配合相应剂量仪DOSE1及验证模体进行绝对剂量的验证;用二维电离室矩阵MATRIXX进行相对剂量的验证.结果 利用电离室在选定的参考点进行绝对剂量的验证,以此为基础,使用二维电离室矩阵进行相对剂量的验证,可以得出患者调强放疗计划执行的误差.结论 该方法切实有效,简单可行,可作为建立调强放疗个体化患者剂量的验证体系.  相似文献   

11.
Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P < 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (>0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P <0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P < 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.  相似文献   

12.
Objective: To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods: SD rats served as both donors and recipients. 4℃ sodium lactate Ringer's was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava (IVC) inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results: Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion: This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.  相似文献   

13.
Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P< 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P< 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.  相似文献   

14.
目的:评价使用安心颗粒对急诊经皮冠状动脉介入术(PPCI)术后生活质量的影响.方法:将160例接受PPCI的急性ST段抬高型心肌梗死患者随机分为安心颗粒组(术前顿服安心颗粒8.8g,术后安心颗粒4.4 g/次,每日2次)和对照组(仅接受基础药物治疗).所有患者均服用阿司匹林、氯吡格雷和阿托伐他汀.分别在入院时、出院前1d、出院后180 d时,应用心肌梗死多维度量表(MIDAS)、中文版SF-36评价量表对患者生活质量评分.并观察术后30 d以内的出血并发症、血小板减少症发生情况.结果:入院时和出院前1d,两组患者的心肌梗死MIDAS、SF-36量表评分比较无差异(P>0.05);出院后180 d时,与对照组比较,安心颗粒组MIDAS、SF-36评分明显减低(P<0.05);组内与入院时比较,两组出院前1d、出院后180 d时,MIDAS、SF-36评分均降低(P<0.05).两组患者在随访期间均无大量出血、少量出血、重度和极重度血小板减少症发生,安心颗粒组有4例、对照组有7例发生不明显出血(P>0.05).两组发生轻度血小板减少症的患者数比较无差异(P>0.05).结论:PPCI使用安心颗粒,能改善急性ST段抬高型心肌梗死患者的生活质量,且不增加出血风险.  相似文献   

15.
Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function,atrio-ventricular node function and hemodynamics.Methods:Thirty-two Angora's rabbits were selected and randomly divided into four groups.U1 group:urapidil 0.25 mg/kg;U2 group:urapidil 0.5 mg/kg;N1 group:nicardipine 10 μg/kg;N2 group:nicardipine 20 μg/kg.All these medicine were administrated within 30 seconds.Measurements were taken before and after the administration of urapidil or nicardipine for the following data:mean blood pressure(MAP),heart rate(HR),sino-atrial conduction time(SACT),maximal sinoatrial recovery time(SNRTmax)corrected sinus node recovery time(CSNRT),index of sinus node recovery time(SNRTI),Wenckebach A-V conduction frequency (WB),and P-R interval.Results:Significant MAP and HR changes were identified in all of the four groups before and after administration of both urapidil and nicardipine.No significant changes could be found in the rest of the parameters.Intergroup analysis showed that SACT and CSNRT of N1 and N2 groups were shorter than those of the U2 group(P<0.01);the MAP decreased(P<0.01)and the HR increased drastically(P<0.01).Conclusions:Neither urapidil(0.25 mg/kg,0.5 mg/kg)nor nicardipine(10μg/kg,20μg/kg)has any significant influence on rabbit sinus function or rabbit atrio-ventricular node function.Nicardipine could be a better choice than urapidil for parafunctional sinus node patients.  相似文献   

16.
Objective:To investigate the gene expression of osteoprotegerin(OPG) and osteoclast differentiation factor(ODF) in the bone tissue of patients with hip fracture due to osteoporosis. Methods:OPGmRNA and ODFmRNA in the bone tissue in 50 cases of osteoporosis sufferers(over 50 years old) with hip fracture(Observer Group) and 30 cases of hip facture sufferers with no osteoporosis(Control group) were analyzed with the Semi-Quantitative RT-PCR method. Results:The mRNA expressed of ODF, OPG were both high in the patients with hip fracture. In the control group, the expression of OPG mRNA was observed, while the expression of ODF mRNA was very slight. Conclusion:Aged patients contained all signals including OPG, ODF that are essential for inducing osteoclastogenesis and promoting bone resorption.  相似文献   

17.
Objective:To investigate the clinical features, pathological characteristics and immunophenotype of solid-pseudopapillary tumor of the pancreas(SPTP). Methods:Nine surgically treated cases of SPTP were retrospectively reviewed. Hematoxylin and Eosin(HE) staining and immunohistochemical staining were used to analyze all cases, and the general clinical data was collected. Results:Six patients were asymptomatic except for a palpable mass. Two patients complained of vague-epigastric pain. One patient appeared jaundice. The tumor was encapsulated and solid tissues alternately with cystic tissues. Histologically, the histological structure of solid portion was pseudopapillary with a fibrovascular core. Tumor cells were uniform and medium-sized which were arranged in sheets ets or nests or pseudopapillary patterns. Immunohistochemical studies demonstrated that SPTP proved positive in vimentin(9/9 cases), AAT(9/9 cases), NSE(9/9 cases), ACT(7/9 cases), CK20(2/9 cases), CgA(1/9 cases), S-100(3/gcases), PR(4/gcases), Syn(3/9 cases) and CD56(5/9cases), negative in CEA and ER. Conclusion:SPTP is a tumor predominantly occurring in young women frequently without special symptoms. This tumor has various characteristical histological patterns with different immunophenotype.  相似文献   

18.
Objective:To probe into the influence of changes of ovarian hormones on the pathogenesis of the specific sub-type premenstrual syndrome(PMS)and reveal partial microcosmic mechanisms of adverse flow of liver-qi.Methods:Estradiol(E2)and progesterone(P)levels in serum were determined at different phases of menstrual cycle by radioimmunoassay.Results:In the group of PMS with adverse flow of liver-qi.the secretive peak value Of E2 and P at the follicular phase significantly decreased,and the secretive peak value at the luteal phase did not come into being.Conclusions:Low E2 and P secretive peak at the follicular phase and absence of secretive peak at the luteal phase is one of the microcosmic mechanisms of PMS with adverse flow of liver-qi.One of the pathophysiologic mechanisms of specific sub-type PMS is probably the continuous low level of E2and P.  相似文献   

19.
Real-time three-dimensional echocardiography (RT3DE)is a new ultrasound technique that enables dynamic threedimensional visualization and quantification of the heart in real time. Investigation of feasibility and methodology of RT3DE in determining left ventricular (LV) and right ventricular (RV) volumes, RT3DE was performed in 35 normal adults using Philips SONOS 7500 system with a 2-4 MHz matrix array transducer. The 60°×60° "pyramid" volume database was obtained and analyzed on a TomTec echo workstation. Both LV and RV volumes were calculated with four 3DE methods (i.e. apical 2, 4, 8, and 16-plane) through manually tracing ventricular endocardial borders in end diastole and end systole. Stroke volumes were then calculated. LV volume was also measured by 2DE Simpson's rule using GE VIVID 7 ultrasound machine.  相似文献   

20.
Increasing maternal age is the only etiological factor unequivocally linked to Down's syndrome in humans. The occurrence rate of newborns with Down's syndrome is about 1/220 in women over 35 years old. However, the occurrence rate in embryos fertilized in vitro, of the elder woman is unclear. Using FISH we screened the number of chromosome 21 in preimplanted embryos of 5 elderly women (average age, 38.4 years) to study the feasibility and necessity of screening trisomy 21 in embryos in patients over 35 years old at the in vitro fertilization (IVF) center.  相似文献   

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