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101.
99Tcm-MIBI动力学变化与大鼠缺血-再灌注心肌存活的相关性研究 总被引:2,自引:2,他引:0
目的探讨用99Tcm-甲氧基异丁基异腈(MIBI)动力学变化评价心肌存活的价值.方法15只离体Krebs-Henseleit(KH)液灌注的鼠心脏,随机分成3组对照组(5只),有葡萄糖的缺血-再灌注组(IR+G组,5只),无葡萄糖的缺血-再灌注组(IR-G组,5只).用含99Tcm-MIBI(14.8MBq)的KH液灌注,观察40min的摄取和清除.用肌酸激酶(CK)分析、氯化三苯四唑(TTC)染色和透射电镜(TEM)分析研究心肌损伤程度,用放射自显影(ARG)观察99Tcm-MIBI在心肌内的分布.结果99Tcm-MIBI的摄取[每克组织百分注射剂量率(%ID/g)]在IR+G组为(7.09±0.97)%ID/g,IR-G组为(6.64±0.68)%ID/g,对照组为(11.44±1.79)%ID/g,IR-G组与IR+G组相比摄取量差异无显著性(P>0.05),IR-G组和IR+G组与对照组相比均显著降低(P<0.05).IR-G组99m-MIBI清除分数为(72.75±9.89)%,远高于对照组[(20.68±1.92)%]和IR+G组[(21.03±3.68)%,P均<0.05],对照组与IR+G组的差异无显著性.99Tcm-MIBI的40min清除末滞留率在IR-G组[(1.82±0.73)%ID/g]和IR+G组[(5.61±0.89)%ID/g]远小于对照组[(9.09±1.57)%ID/g,P<0.05],IR-G组也远小于IR+G组(P<0.001).CK分析、TFC染色和TEM分析证明IR-G组比IR+G组有更多的心肌损伤.通过TTC染色(r=0.84,P<0.05)和CK分析(r=-0.97,P<0.05)确定最终99Tcm-MIBI的活度与存活心肌量高度相关,通过ARG证实99Tcm-MIBI分布于鼠心肌细胞及间质内(光镜下).结论99Tcm-MIBI的清除对代谢状态敏感,可用于评价进行性心肌损伤. 相似文献
102.
L A Denisova R G Maev I Ya Poyurovskaya T V Grineva A F Denisov E Yu Maeva E Yu Bakulin 《Dental materials》2004,20(4):358-363
OBJECTIVES: The aim of the study was to investigate the relationship between microstructure, acoustic and mechanical properties of hardened dental cement samples, prepared with different powder/water ratios. METHODS: Glass-ionomer dental cement samples, prepared with a standard amount of cement powder and different amounts of water have been examined after being hardened. Surface microstructure and ultrasound, longitudinal and shear velocities were obtained with a scanning acoustic microscope. Conditional effective elastic modulus and Poisson's ratio have been calculated using longitudinal and shear sound velocity values. Then on the same samples elastic modulus and microhardness have been determined by standard tests. Additional samples have been used to determine compressive strength. RESULTS: Density; conditionally instantaneous elastic modulus; high-elasticity modulus and compression strength of the samples decrease when large amounts of water were used for their preparation. At the same time porosity and microhardness of the cement matrix increase. Acoustic parameters and parameters of elasticity, calculated on the basis of sound velocity, demonstrated changes, similar to those obtained in standard mechanical tests. SIGNIFICANCE: The established relation between microstructure, acoustic and mechanical parameters demonstrated a high capacity of acoustic microscopy application for non-destructive characterization of dental materials. A particular advantage of the acoustic microscopy is the opportunity to evaluate microstructure and mechanical properties on the same sample. 相似文献
103.
T. V. Nalapko V. G. Skvortsov Yu. Ya. Kharitonov N. B. Epstein 《Pharmaceutical Chemistry Journal》2010,44(9):504-506
This review gives a brief outline of the history of development of radiopharmaceuticals (RPh) for radionuclide diagnostics
of bone pathology. The advantages of RPh based on 99mTc-diphosphonates are demonstrated. 相似文献
104.
105.
Dolzhenko A. V. Koz'minykh V. O. Kolotova N. V. Burdi N. Z. Kotegov V. P. Novoselova G. N. Syropyatov B. Ya. 《Pharmaceutical Chemistry Journal》2003,37(7):342-344
Pharmaceutical Chemistry Journal - 相似文献
106.
Dolzhenko A. V. Koz'minykh V. O. Kolotova N. V. Syropyatov B. Ya. Novoselova G. N. 《Pharmaceutical Chemistry Journal》2003,37(5):229-231
Pharmaceutical Chemistry Journal - 相似文献
107.
Cells in the premedullar zone of the thymus contain serotonin and catecholamines and show argyrophilicity in the Grimelius
test. Their cytoplasm is packed with granules. Glucocorticoids (hydrocortisone) provoke an increase in the number of argyrophilic
premedullary cells and in their content of serotonin and catecholamines. Mineralocorticoids induce a prolonged (1–14 days)
increase in the number of argyrophilic premedullary cells, enhance their degranulation, and increase their contents of serotonin
(2–3 fold) and catecholamines.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 10, pp. 461–464, October, 1996 相似文献
108.
Summary It is difficult for conventional transthoracic echocardiography (TTE), by which precise and accurate images of interatrial
septum (IAS) can not be acquired, to diagnose patent foramen ovale (PFO) clearly. To evaluate the diagnostic value of biplanar
transesophageal echocardiography (TEE) for PFO, TTE and biplanar TEE were performed simultaneously in 270 patients. It was
found that in 7 patients patent foramen ovale was detected only through longitudinal planes of biplanar TEE. IAS, which consists
of primitive septum and membrane of fossa ovalis, can be directly visualized by two-dimensional images of TEE; in patients
with PFO, a dull color flow, which shunts from the right atria to the left atria through the gap between primitive septum
and fossa ovalis, can be detected by color Doppler flow images. Furthermore, some right-to-left shunting microbubbles through
the valve of patent fossa ovalis can be discovered by cardiac acoustic contrast echocardiography. In conclusion, biplanar
TEE combined with color Doppler image and cardiac acoustic contrast facilitates a definite diagnosis of patent foramen ovale
as the excellent anatomic images of IAS can be obtained from multiple views under this kind of performance. 相似文献
109.
110.
肝炎和肝硬化患者胆囊超声改变的观察与分析 总被引:7,自引:0,他引:7
目的 :研究肝炎肝硬化患者胆囊彩色B超声像图变化 ,并探讨其临床意义。方法 :采用彩色超声诊断仪对 139例肝炎和肝硬化患者及 4 2例非肝炎体检者进行胆囊超声检查。结果 :慢性肝炎、重型肝炎、肝硬化患者组与非肝炎对照组彩色B超胆囊异常率比较均差异显著 (P <0 .0 1)。重型肝炎、肝硬化组与慢性肝炎组之间胆囊异常率也存在明显的差异 (P <0 .0 5 )。结论 :慢性肝病患者胆囊异常与胆囊本身炎症无关。胆囊声像图的改变对判断肝脏实质性病变的严重程度及指导临床治疗有一定的参考价值。 相似文献