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1.
L-[1-13C]苯丙氨酸呼气试验定量检测肝功能研究   总被引:4,自引:0,他引:4  
为评价L-[1- 13C]苯丙氨酸呼气试验检测肝功能的可行性和有效性,健康自愿者、代偿期肝硬化患者和失代偿期肝硬化患者各10名,口服100mg L-[1- 13C]苯丙氨酸后进行呼气试验.应用气体同位素比值质谱仪测量服药前和服药后至360min各时间点气样中的13C丰度,得到了不同时间的13C的排除速率13CO2ERt (percentage 13C excretion rate) (% 13C剂量/h)和各时相内的累计13C排除率13Ccumt (percentage 13C cumulative excretion) (% 13C剂量).将呼气试验参数30 min 13C排除速率13CO2ER30和75min累计13C排除率13Ccum75在正常对照组、肝硬化代偿组、肝硬化失代偿组之间进行两两比较,并分别与各肝功能临床生化指标进行相关性分析.结果显示,13CO2ER30(肝硬化代偿组7.4% 13C剂量/h±1.0% 13C剂量/h;肝硬化失代偿组3.5% 13C剂量/h±1.1% 13C剂量/h;正常对照组12.1% 13C剂量/h±2.1% 13C剂量/h)和13Ccum75(肝硬化代偿组7.0% 13C剂量±1.1% 13C剂量;肝硬化失代偿组3.8% 13C剂量±1.0% 13C剂量;正常对照组10.6% 13C剂量±1.6% 13C剂量)在各组之间差异均具有显著性(P<0.001);13CO2ER30和13Ccum75与部分肝功能生化指标存在显著相关性(P<0.05).表明口服L-[1- 13C]苯丙氨酸呼气试验是一种简便、灵敏、特异、定量的肝功能即时检测方法;13CO2ER30和13Ccum75是有效的肝功能评价参数.  相似文献   

2.
188Re-tin sulfur colloid (TSC) was prepared to compare its biodistribution characteristics with 188Re-macroaggregates album (MAA) after transhepatic arterial embolization (TAE) in rabbits bearing VX2 liver tumor. Labeling efficiencies of the 188Re-TSC and 188Re-MAA were 99.94%±0.04% and 99.95%±0.03%, respectively,and they were stable for 72 h in human serum. Sintigraphy and biodistribution in 31 rabbits bearing VX2 liver tumor after transcatherter hepatic arterial injection of the radiopharmaceuticals were performed, and relevant activity accumulated mostly in the tumor. The percentage of the injected dose per gram of wet tissue (%ID/g) of 188Re-TSC and 188Re-MAA were calculated. Tumor uptake of 188Re-TSC at 1 h and 24 h were 24.32%±11.93% and 21.88%±18.29%, and the radioactive ratios of tumor/liver were 70.89±19.58 and 17.42±13.96, respectively. Tumor uptake of 188Re-MAA at 1 h and 24 h were 38.78%±30.23% and 15.98%±96.64%, and the radioactive ratio of tumor/liver of 188Re-MAA were 39.71±95.06 and 8.13±4.61, respectively. 188Re-TSC is a potential radiopharmaceutical for the therapy of tumors.  相似文献   

3.
重离子辐照诱导DNA双链断裂的剂量率效应   总被引:5,自引:0,他引:5  
利用不同剂量率的50MeV/u^12C^6 辐照B16黑色素瘤细胞的脱蛋白DNA,采用脉冲场凝胶电泳技术对DNA双链断裂(DSB)的诱导和片段的分布进行了研究。结果发现,在剂量率分别为3Gy/min和30Gy/min的情况下,DNA片段释放百分比(PR)都随着剂量的增加而增加,并在超过一定剂量之后趋于相似的准阈值;3Gy/min辐照诱导DSB的产额为0.40DSBs(100Mbp.Gy),30Gy/min辐照诱导的DSB产额准确值无法得到;30Gy/min辐照诱导DSB的截面为2.14μm^2,是3Gy/min的3.1掊。所有结果都表明剂量率越高,诱导DSB越有效。另外,3Gy/min辐照诱导DSB片段在-860kbp处有一个片段峰,而30Gy/min没有,说明剂量率可以影响DSB片段的分布。  相似文献   

4.
摘要:采用氧化燃烧炉技术处理小鼠灌胃给予3H-β,β-二甲基丙烯酰紫草素后的组织、粪样(尿样直接加闪烁液测定),用液闪计数仪测定其放射性水平,并采用HPLC 技术分析生物样品,以研究其放射性在小鼠体内的组织分布与排泄情况。研究结果显示,胃肠道放射性浓度最高,肝脏、肺脏、肾脏、心脏等组织内放射性浓度次之,骨骼肌、脊髓、脑中分布较少;小鼠灌服 3H-β,β-二甲基丙烯酰紫草素(84mg/kg,22.3MBq/kg)后336h从粪中收集到给药总放射剂量的(72.879.92)%,尿液中回收到(6.810.18)%,粪尿合计(79.68±0.18)%;小鼠粪便中以原形药物为主,血浆、尿样中均未检测到原形药物。上述结果提示,3H-β,β-二甲基丙烯酰紫草素在小鼠体内分布广,排泄较完全,经粪便排泄为主,经肾排泄为辅。  相似文献   

5.
This work is to study the in vivo biological distribution of 131I-labeled mouse/human chimeric monoclonal antibody (131I-chTNT) in patients with pulmonary metastases from differentiated thyroid carcinoma.Ten patients with differentiated thyroid carcinoma were injected intravenously with a single dose of 131I-chTNT (5 MBq.kg-1 body weight).Radioactivity of blood and urine samples was measured at different time points.The in vivo stability and the metabolic status of 131I-chTNT were detected with supersaturated trichloroacetic acid.Continuous imaging was performed to outline the region of interest (ROD and estimate the intake level on the whole body,major organs and tumor lesions at different time points.The serum time-radioactivity curve of 131I-ehTNT accorded with the two-compartment model after a single intravenous injection:T1/2(h)=65.28±14.83,AUC0-t(MBq.h.mL-1)=8.93±1.32,AUC0-∞(MBq-h-mL-1)=10.58±2.19,and CL(mL.min-1.kg-1)=1635±359.The time-radioactivity percentage curve of 131I-chTNT urine excretion accorded with the one-compartment model after a single intravenous injection:T1/2(h)=99±10,and accumulative (31±9) % radioactivity of the injected dose was excreted in urine in one week.The percentages of serum 131I-ehTNT in radioactive components at 24,48 and 72 h were over 95% and it was still (88±7)% at 168 h.As for chemical composition of radioactive substances in urine,radioactivity in urine samples originated from free 131I by 100%.Radioactivity of 131I-chTNT after intravenous administration was mainly concentrated in the lung and liver,least in the brain.Radioactivity of tumor tissues reached the maximum at 24 h and the tumor/normal tissue (T/N) ratio reached the maximum (1.28~3.83) during 3~7 d.The characteristics of in vivo biological distribution of 131I-chTNT in patients with pulmonary metastases from differentiated thyroid carcinoma are favorable for its therapeutic application for the metastasis tumors.  相似文献   

6.
Iron-ion irradiations were carried out for 0.09wt%Cu A533B steel specimens at 290°C to investigate effects of dose rate change during irradiation; the irradiations consisted of the base irradiation (with an unchanged dose rate) and an additional one with changed dose rates from 1 to 50 times that of the base one. Nano-indentation hardness measurements showed that the increase in hardness was higher for lower dose rate of the base irradiation. A similar trend was identified during the additional irradiation. Transmission electron microscope (TEM) and three-dimensional atom probe (3DAP) analyses were carried out for the quantitative characterization of defect features. Mn/Ni/Si/Cu-enriched clusters and dislocation loops were observed in all specimens. The increase in hardness mainly depended on the formation of the solute atom clusters. The square root of the volume fraction of the solute atom clusters provided a good correlation with the increase in hardness. The effects of dose rate and dose rate change during irradiation were explained by the formation of solute atom clusters.  相似文献   

7.
1 Introduction Radioiodide therapy using 131I is effective for pa-tients who have metastasis from differentiated thyroidcancer. This therapy is based on the uptake of radioac-tive iodide into cancer cells, as is observed in thyroidcells, to …  相似文献   

8.
《同位素》2007,20(4):199-205
99TcmN DBODC5 for intravenous injection was prepared. The labelling yield was 95.0%±0.52%. Sixteen New Zealand rabbits were involved and planar gamma imaging was performed at 10 time point after injection of 99TcmN DBODC5. The radioactivity channes of organs were calculated by regions of interest (ROI) analysis. The 16 rabbits were divided into 4 groups and were sacrificed at 30, 60, 120, and 180 min after injection respectively. The activity for all excised organs were measured by γ well counting for calculating radiouptake. Myocardial uptake for 99Tcm N DBODC5 is high. Though myocardial uptake was lower than 99Tcm MIBI, the liver clearance for 99TcmN DBODC5 was more rapid than that of 99Tcm MIBI. As early as 30 min after injection, 99TcmNDBODC5 heart to liver ratio is 0.98±0.52 versus 0.56±0.19 for 99Tcm MIBI (P<0.01). At 60 min post injection, 99TcmNDBODC5 heart to liver ratio improved to the peak value (1.18±0.57), compared with 0.71±0.29 for 99Tcm MIBI, P<0.01. After 60 min, the heart to liver ratio of 99Tcm N DBODC5 was keeping at a high level until 180 min. 99Tcm N DBODC5 exhibited rapid lung clearance, similar to that of 99Tcm MIBI. The biodistribution in the isolated organs demonstrated the same trend. The rapid 99Tcm N DBODC5 liver clearance may allow the earlier imaging, and overcome the photon scatter from the liver with high activity which interfered the inferoapical wall in myocardial images. 99Tcm N DBODC5 is a promising new myocardial perfusion imaging agent with superior biodistribution properties.  相似文献   

9.
ADAM (2-((2-((dimethylamino)methyl)phenyl)thio)-5-iodophenylamine) is suggested as a promising serotonin transporter (SERT) imaging agent for central nervous system. In this paper, biodistribution studies in rats showed that the initial uptake of 131I-ADAM in the brain was high (1.087%ID at 2 min post-injection), and consistently displayed the highest binding (between 60~240 min post-injection) in hypothalamus, a region known with the highest density of SERT. The specific binding((T/CB)-1) of 131I-ADAM in hypothalamus were 2.94, 3.03 and 3.09 at 60, 120 and 240 min post-injection, respectively. The (T/CB)-1 was significantly blocked by pretreatment with paroxetine, which is known as a serotonin site reuptake inhibitor, while another nonselective competing drug (5HT2A antagonist) Ketanserin, showed no block effect. The rat brain autoradiography and analysis showed that there was a high 131I-ADAM uptake in hypothalamus, the ratio of hypothalamus/cerebellum was significantly reduced from 7.94±0.39 to 1.30±0.56 by pretreatment with paroxetine at 60 min post-injection. Blood clearance kinetics was performed in rats, and the initial half-life of 13.79 min and late half-life of 357.14 min were obtained. The kinetic equation is: C=3.6147e-0.0725t 1.0413e-0.0028t. The thyroid uptake was 0.009% ID and 1.421% ID at 2 min and 120 min post-injection, respectively, suggesting that in vivo deiodination may be the major route of metabolism. Toxicity trial showed that the dose per kilogram administered to mice was 1000 times greater than that to humans, assuming a weight of 50kg. These data suggest that 131I-ADAM may be useful for SPECT imaging of SERT binding sites in the brain.  相似文献   

10.
Two transients, an open grid and a scram at 50% load, were conducted on unit 4 of the PWR power plant Bugey. The thermal hydraulic response of the steam generator was recorded. For the open grid test, the following observations are noted:No alarming phenomena are observed in the steam generator during the transient. Primary pressure oscillations were very mild, and did not exceed about 4.8 bar/min with a maximum amplitude of ±8 bar. This condition should not result in significant stress levels. Steam generator outer shell metal temperature gradients remained within very acceptable limits; a maximum amplitude of about +13°C and a rate not exceeding 0.8°C/min are obtained. This slow rate is explained by a fall in primary water temperature that allows for a temperature decrease inside the U-tube bundle. Similarly, the temperature rise on the tube sheet does not exceed an amplitude of 20°C with a rate of about 2°C/min. Again these conditions do not lead to any significant thermal shock on the tube sheet. The steam generator feed controls maintain the level within the normal operation range and the small addition of colder feedwater does not lead to great temperature changes because of the large mass of the recirculation water in the steam generator.For the scram at 50% load, the following observations are noted: no severe thermal or pressure transients are observed in this test. Fluid temperature fluctuations occur with rates not exceeding 1°C/s and a maximum amplitude of about 20°C in the downcomer and 10°C on the tube sheet. Steam generator outer shell temperature varies at a rate of about ±0.8°C/min with a maximum amplitude of about 16°C. These thermal transients should lead to thermally induced stresses of acceptable levels.  相似文献   

11.
Uranium removal efficacy of fullerence multi-macrocyclic polyamine derivatives(C60-MMP),a novel chelating agent,was evaluated in mice.C60-MMP was administrated intravenously into mice at 30 min after the uranium contamination.The molar ratio of chelating ligand/uranium was about 1:1.The results indicate that C60-MMP can effectively prevent accumulation of uranium in liver at 8 h after C60-MMP injection.At 48 h after the last injection,uranium deposition in liver of C60-MMP treated mice is approximately 65%less than that of the control group.C60-MMP reacted positively in promoting the removal of uranium from kidney,and the urinary uranium excretion increased significantly,compared with the control and DTPA-treated mice.However,repeated administration of C60-MMP,and combined injection of DTPA and C60-MMP,did not show desirable effects on uranium removal from mice.It implies that more investigations are needed for the treatment protocols and clinical applications of C60-MMP.  相似文献   

12.
建立了一种γ吸收剂量率实时在线测量系统,研究了半导体硅光电池BBZSGD-4辐射光生电流和γ吸收剂量率之间的关系,并对其耐辐照性能进行了研究。60 Coγ辐照实验表明:半导体硅光电池BBZSGD-4对60 Co的γ射线有较好的响应,其辐射光生电流与吸收剂量率的关系呈线性规律。当吸收剂量率为94.54Gy/min时,辐射光生电流可达1.26μA。在吸收剂量率为50Gy/min时,辐射光生电流随总吸收剂量的增加呈指数下降,总吸收剂量为5 445.8Gy时,其辐射光生电流衰减1%。半导体硅光电池BBZSGD-4具有作为实时在线低吸收剂量率探测器的潜力。  相似文献   

13.
通过核素心血池显像测定静息和等长运动冠心病患者左室功能指标的变化,探讨等长运动核素心血池显像对冠心病诊断的临床价值。8例正常人、38例冠心病患者静息状态下核素心血池显像后,双手握力5—10min并同时进行采集从而获得静息和运动状态下两组心功能指标,并且行冠状动脉及左室造影。统计方法用t检验和四格表等效检验。结果表明,左室射血分数(LVEF)、高峰充盈率(PFR)、左室舒张末期容积(EDV)、左室收缩末期容积(ESV)和心率(HR)在静息状态下,对照组和冠心病一、二、三支冠脉病变组分别为(57±10.45)%、(53.67±5.0)%、(52.47±8.26)%、(52.81±8.89)%,p=NS;2.94±0.44、2.87±0.29、2.71±0.88、3.07±0.71(EDV/s),p=NS;1.38±0.15、1.36±0.05、1.34±0.06、1.34±0.06,p=NS;0.59±0.11、0.62±0.06、0.66±0.06、0.65±0.1,p=NS;72.88±8.25、69.67±8.14、72.85±10.5、76.56±18.04(min  相似文献   

14.
等效剂量的准确测定是进行地质样品热释光年龄测定的关键。采用不同辐照间隔增量测量泥石流物质标样,测得的等效剂量值是不同的,说明辐照剂量增量对泥石流物质样品等效剂量值存在影响。测试选用已知等效剂量为30 Gy的泥石流标样,按不同的辐照剂量增量进行等效剂量测定。2.5Gy/min的β源(90Sr-90Y)辐照剂量增量分别选用1、2、4、6 min时,测得的等效剂量分别为19.3、22.3、26.4、23.0 Gy;8 Gy/min的β源(90Sr-90Y)辐照剂量增量分别选用0.5、1、1.5、2 min时,测得的等效剂量分别为17.6、19.6、25.3、15.6 Gy。研究表明:对于30 Gy的泥石流标样,剂量率为2.5 Gy/s的β源(90Sr-90Y)测定泥石流物质时最适合的辐照剂量增量为4 min。剂量率为8 Gy/s的β源(90Sr-90Y)测定泥石流物质时最适合的辐照剂量增量为1.5 min。  相似文献   

15.
研究铀矿尘所致人支气管上皮细胞遗传毒性以及茶多酚对细胞的防护作用,为铀矿尘的防护提供理论依据。将细胞分为3组:对照组、铀矿尘组(高中低剂量组)、茶多酚保护组,采用微核多核实验、彗星实验、HPRT基因突变检测及染色体分析研究铀矿尘对支气管上皮细胞的遗传毒性作用及茶多酚防护作用。BEAS-2B细胞经铀矿尘染毒后,与对照组相比,彗星细胞数(高剂量组156.75±8.26)、彗星尾长(高剂量组164.48±12.11μm)、尾距(高剂量组109.92±10.53)均显著意义的增加(p<0.05),并有剂量—效应关系;茶多酚对此有明显的抑制作用。铀矿尘能诱发微核细胞(高剂量组120.25‰)、多核细胞增多(高剂量组74.50‰),茶多酚对微核多核细胞增多有抑制作用(p<0.05)。铀矿尘作用于BEAS-2B细胞后引起HPRT基因突变率增加(高剂量组1.092‰),茶多酚能有效地降低HPRT基因突变率。染色体分析结果表明,经染毒后转化细胞可出现染色体非稳定性畸变,茶多酚对染色体畸变具有抑制作用。铀矿尘具有较强的遗传毒性,茶多酚对铀矿尘的遗传毒性具有防护作用。  相似文献   

16.
本文报道了狗的急性铀中毒和用 Tiron 进行急救治疗的实验结果。观察指标包括尿铀排除率、主要的临床生物化学指标、病理组织学以及病程经过。结果表明,Tiron 或 Tiron 与碳酸氢钠伍用,显示较好的急救治疗效果。  相似文献   

17.
钟建国  宋天琦 《同位素》2006,19(4):246-249
用高效液相色谱法测定了尿素[13C]混合粉中的尿素[13C]含量。用Alltech Econosphere NH2柱(250mm×4.6mm,5µm)作色谱柱,色谱条件为:V(乙腈):V(甲醇):V(水)=900:100:10为流动相,流速为1mL•min-1,检测波长为200nm,进样量为20 µL。尿素[13C]在0.2~1.0 mg•mL-1浓度范围内,呈良好的线性关系,回归方程为:y=2.548×106x+4.005×104 ,r=0.9999,平均回收率为100.6%。本法简便、准确,适于尿素[13C]混合粉的质量控制。  相似文献   

18.
18F标记哒嗪酮类似物的制备及其在小鼠体内的生物分布   总被引:1,自引:0,他引:1  
设计并合成了一种18F标记哒嗪酮类似物:2-特丁基-4-氯-5-(2 氟[18F]乙氧基)-2H-3-哒嗪酮(18F-FP2),通过生物分布实验评价了其用于心肌灌注显像的可行性。18F-FP2的总制备时间为70~90 min,校正后的放化产率为53.0%±5.2%,放化纯度>98%;18F-FP2为脂溶性化合物,在水溶液中可稳定放置3 h以上。生物分布实验结果显示,18F-FP2在肝、肺中初期摄取高,注射后2 min分别为(14.53±2.36)%ID/g和(33.69±10.79)%ID/g,但清除很快,注射后15 min,其肝、肺的清除率已分别达57.7%和86.2%。18F-FP2的心肌摄取较低,最高摄取值为(4.09±0.53)%ID/g(注射后2 min)。这可能因标记侧链上未带苯环造成的,说明哒嗪酮侧链的芳环结构对心肌的摄取与滞留有较大影响。  相似文献   

19.
Non-thermal plasma surface modification for epoxy resin(EP)to improve the insulation properties has wide application prospects in gas insulated switchgear and gas insulatedtransmission line.In this paper,a pulsed Ar dual dielectrics atmospheric-pressure plasma jet(APPJ)was used for Si C_xH_yO_zthin film deposition on EP samples.The film deposition was optimized by varying the treatment time while other parameters were kept at constants(treatment distance:10 mm,precursor flow rate:0.6 l min~(-1),maximum instantaneous power:3.08 k W and single pulse energy:0.18 m J).It was found that the maximum value of flashover voltages for negative and positive voltage were improved by 18%and 13%when the deposition time was3 min,respectively.The flashover voltage reduced as treatment time increased.Moreover,all the surface conductivity,surface charge dissipation rate and surface trap level distribution reached an optimal value when thin film deposition time was 3 min.Other measurements,such as atomic force microscopy and scanning electron microscope for EP surface morphology,Fourier transform infrared spectroscopy and x-ray photoelectron spectroscopy for EP surface compositions,optical emission spectra for APPJ deposition process were carried out to better understand the deposition processes and mechanisms.The results indicated that the original organic groups(C–H,C–C,C=O,C=C)were gradually replaced by the Si containing inorganic groups(Si–O–Si and Si–OH).The reduction of C=O in ester group and C=C in p-substituted benzene of the EP samples might be responsible for shallowing the trap level and then enhancing the flashover voltage.However,when the plasma treatment time was longer than 3 min,the significant increase of the surface roughness might increase the trap level depth and then deteriorate the flashover performance.  相似文献   

20.
基于薄塑料闪烁体探测器,采用MC模拟优化了定向剂量当量率监测仪探头组合结构。研制的用于弱贯穿辐射监测的定向剂量当量率仪,在10 μSv/h~100 mSv/h范围内,相对固有误差<± 6%;85Kr的β辐射场中,-60°~60°范围内角度响应好于± 40%;β辐射平均能量在60 keV~800 keV内,能量响应变化在-24%~49%范围内;变异系数小于2%。实验测量结果表明,该定向剂量当量率仪辐射性能满足GB/T 4835.1—2012要求。  相似文献   

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