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21.
22.
A. Merzak C. Parker S. Koochekpour G. V. Sherbet G. J. Pilkington 《Neuropathology and applied neurobiology》1994,20(6):614-619
Invasion of the reconstituted extracellular matrix composite, Matrigel, by eight human glioma–derived cell lines and human fetal brain cells was assessed in vitro using 8 um polycarbonate filters in a modified Boyden migration chamber. With the exception of one low grade glioma derived cell line, all lines studied proved to be invasive while normal fetal brain cells failed to invade. This invasive potential was independent of the histological grade of the tumour from which the cell lines originated. In addition, the expression of the metastasis–associated gene 18A2lmts1 as well as the tissue inhibitor of metalloproteinases–2 (TIMP–2) was analysed in each of the glioma–derived cell lines. The 18A2/mtsl was expressed in all the cells studied with the exception of fetal brain cells and the low grade non–invasive glioma derived IPRK–7 cell line. The 18A2/mtsl related genes coding for the S100 subfamily of calcium binding proteins were found to be differentially and overexpressed in invasive cell lines. TIMP–2 was expressed only in noninvasive cell lines. These results suggest that the 18A2/ mtsl and TIMP–2 genes could play an important role in the invasive behaviour of human glioma cells in vitro. . 相似文献
23.
S. Leskinen-Kallio 《Clinical physiology and functional imaging》1994,14(3):329-335
Summary. The particular advantages of positron emission tomography (PET) technique are that it has higher sensitivity, higher resolution, and a higher quality of image than that found in conventional nuclear medicine. The possibility of quantification and the wide range of useful tracers have raised expectations of this new method. To date, most of the human PET cancer studies have been performed with [18F]fluorodeoxyglucose (FDG) or [11CJmethionine. These are good imaging agents for tumours. However, more specific radiopharmaceuticals are required if other features of tumour metabolism are to be observed, f11Thymidine may prove to be a good tracer for quantitative measurements of tumour proliferation and [18F]misonidazole has been suggested for imaging of hypoxia. 相似文献
24.
Molecular identification of a small supernumerary marker chromosome by in situ hybridization: diagnosis of an isochromosome 18p with probe L1.84 总被引:1,自引:0,他引:1
A dysmorphic child was found by cytogenetic analysis to have an extra small marker chromosome. The marker chromosome was shown to possess a chromosome 18 centromere by in situ hybridization, and probably represents an isochromosome 18p. Centromere specific probes should be of value in identifying extra small marker chromosomes, and thereby provide better understanding of the clinical significance of these. 相似文献
25.
Gérald Vanzetto Marc Janier Daniel Fagret Luc Cinotti Xavier André-Fouet Michel Comet Jacques Machecourt 《European journal of nuclear medicine and molecular imaging》1997,24(2):170-178
The best test presently available to ascertain residual viability within an infarct-related area involves the use of fluorine-18
fluorodeoxyglucose (FDG) to detect the persistence of some cellular metabolism. Rest reinjection of thallium-201 is a less
accurate alternative but is easy to perform. Iodinated fatty acids, which are used with standard gamma cameras, are proposed
as markers of cellular metabolism. This study was performed to assess the value of 16-iodo-3-methyl-hexadecanoic acid (MIHA)
as a marker of the residual cellular metabolism by comparison with FDG in patients with a recent myocardial infarction, and
to evaluate its contribution compared with the201Tl stress-redistribution-reinjection technique. Stress-redistribution-reinjection201T1 imaging, rest MIHA imaging and glucoseloaded FDG imaging were performed in 22 patients with recent myocardial infarction.
Out of the 628 myocardial segments obtained from the left ventricular analysis, 400 were hypoperfused (relative uptake <0.75
of maximum uptake on stress201T1 imaging), 177 of which were severely hypoperfused (relative uptake <0.50). Receiver operating characteristic (ROC) curves
for predicting metabolic myocardial viability with FDG were derived from the results in respect of (a)201T1 activity during exercise, redistribution and reinjection and (b) MIHA up-take, using the two FDG thresholds most commonly
considered to define metabolic viability (0.50 and 0.60). Analysis of the 400 hypoperfused segments demonstrated that201T1 reinjection was the most accurate test in predicting the presence of myocardial viability (area under the ROI curves=0.85
and 0.86 at the 0.50 and 0.60 FDG thresholds, respectively;P<0.05 vs other tests). The global predictive values of MIHA and201T1 reinjection were, respectively, 0.87 and 0.89 at the 0.50 FDG threshold (NS), and 0.82 and 0.87 at the 0.60 FDG threshold
(NS). When only the 177 severely hypoperfused segments were considered,201T1 reinjection remained the most accurate test (accuracy 0.84 at the 0.50 FDG threshold and 0.82 at the 0.60 FDG threshold),
while the accuracy of MIHA decreased significantly (0.78 at the 0.50 FDG threshold and 0.73 at the 0.60 FDG threshold,P<0.05 vs201T1 reinjection). In all circumstances, MIHA was less specific than201T1 reinjection for the detection of metabolic viability. In conclusion, in patients with recent myocardial infarction, MIHA
accurately detects the persistence of metabolic viability, but is not superior to201T1. 相似文献
26.
Myocardial metabolic imaging by means of fluorine-18 deoxyglucose/technetium-99m sestamibi dual-isotope single-photon emission tomography 总被引:2,自引:1,他引:1
Hans-Peter Stoll Nicola Hellwig Christof Alexander Cem Özbek Hermann Schieffer Erich Oberhausen 《European journal of nuclear medicine and molecular imaging》1994,21(10):1085-1093
The detection of preserved glucose uptake in hypoperfused dysfunctional myocardium by fluorine-18 deoxyglucose (FDG) positron emission tomography (PET) represents the method of choice in myocardial viability diagnostics. As the technique is not available for the majority of patients due to cost and the limited capacity of the PET centres, it was the aim of the present work to develop and test FDG single-photon emission tomography (SPET) with the means of conventional nuclear medicine. The perfusion marker sestamibi (MIBI) was used together with the metabolic tracer FDG in dual-isotope acquisition. A conventional SPET camera was equipped with a 511-keV collimator and designed to operate with simultaneous four-channel acquisition. In this way, the scatter of 18F into the technetium-99m energy window could be taken into account by a novel method of scatter correction. Thirty patients with regional wall motion abnormalities at rest were investigated. The results of visual wall motion analysis by contrast cine-ventriculography in nine segments/heart were compared with the results of quantitative scintigraphy. The scintigraphic patterns of MIBI and FDG tracer accumulation were defined as normal, matched defects and perfusion-metabolism mismatches. Spatial resolution of the system was satisfactory, with a full width at half maximum (FWHM) of 15.2 mm for 18F and 14.0 mm for 99mTe, as measured by planar imaging in air at 5 cm distance from the collimator. Image quality allowed interpretation in all 30 patients. 88% of segments without relevant wall motion abnormalities presented normal scintigraphic results. Seventy-five akinetic segments showed mismatches in 27%, matched defects in 44% and normal perfusion in 29%. We conclude that FDG-MIBI dual-isotope SPET is technically feasible with the means of conventional nuclear medicine. Thus, the method is potentially available for widespread application in patient care and may represent an alternative to the 201T1 reinjection technique. 相似文献
27.
30例新鲜胃癌标本,采用多聚酶链反应技术检测人类乳头瘤病毒16、18感染、并采用多聚酶链反应-单链构象多态性技术对p53基因突变进行检测。结果:HPV15阳性率为40.0%,未发现HPV18感染:P53基因突变率为50.0%,HPV16感染和P53基因突变同时存在者为16.7%。 相似文献
28.
4,7,13,16,21,24-Hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane (Kryptofix® 2.2.2) is used in the routine preparation of [18F]-labeled tracers employed in positron emission tomography (PET) imaging. Confirming the absence of Kryptofix® in radiopharmaceuticals is a quality control criterion required before they can be released for human use. Analysis of Kryptofix® levels using the iodoplatinate spot-test can be complicated by false-positive results due to nitrogen containing tracers and/or false-negative results caused by added stabilizers. To overcome this issue, we have developed a universal TLC method for the rapid and reliable determination of Kryptofix® levels in the wide range of fluorine-18 radiopharmaceuticals we prepare, including complex multi-component formulations. 相似文献
29.
详细分析了参数记录数据在Tracerlab FX-FDG上的合成过程,以及造成合成故障的确切原因,从而得出正确的结论,即:对液体的添加过程是否正常,数据记录可提供准确信息,是解决问题可依赖的分析手段。 相似文献
30.
目的 对甘利欣辅助治疗皮肌炎、系统性红斑狼疮的临床疗效及安全性进行临床评价。方法 采用非盲法半随机对照法,试验组10例,对照组11例,均据病情需要使用激素,试验组辅以静滴甘利欣250~300mg/d,观察2~3周。结果 皮肌炎、系统性红斑狼疮对照组的总有效率为72.7%,试验组为80%;但两组间差异无统计学意义(P〉0.5)。皮损好转及生化酶学改变亦无统计学意义。不良反应轻微。结论 甘利欣辅助治疗皮肌炎、系统性红斑狼疮的临床疗效尚需进一步研究。 相似文献