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1.
Several cocaine congeners are of potential for imaging the dopamine transporter (DAT). Previous studies have shown that iodine-123 labelled 2-carbomethoxy-3-(4-iodophenyl)tropane ([123I]-CIT) is a promising radiotracer for imaging the serotonin (5-HT) and dopamine (DA) transporters in the living human brain with single-photon emission tomography (SPET). [123I]-CIT was found to be not very practical for 1-day DAT imaging protocols since peak DAT uptake occurs later than 8 h. Here we report a pilot comparison of [123I]-CIT and 2-carbomethoxy-3-(4-iodophenyl)-N-(3-fluoropropyl)nortropane ([123I]-CIT FP), using SPET imaging in four healthy male subjects. Peak uptake of [123I]-CIT-FP into the basal ganglia occurred earlier (3–4 h after injection of tracer) than that of [123I]-CIT (>8 h). However, the specific DAT binding of [123I]-CIT-FP in the basal ganglia was somewhat less (0.813±0.047) than that of [123I]-CIT (0.922±0.004). Imaging quality is excellent with both tracers and they are potentially of value for brain imaging in various neuropsychiatric disorders.  相似文献   

2.
Zusammenfassung Die Annahme der a-priori-Wahrscheinlichkeit, daß Nichtväter und wahre Väter gleichhäufig zur Begutachtung gelangen, wird an Hand von 408 Aktenfällen bestätigt.Die Berechnung der Vaterschaftswahrscheinlichkeit bietet, insbesondere bei Mehrverkehrsfällen, wertvolle Hinweise für die Vaterschaft oder Nichtvaterschaft eines Probanden, Hinweise, die durch die Angabe der Vaterschaftsausschlußchance aufgrund der Mutter-Kind-Konstellation nicht erbracht werden können. Auf Beziehungen zwischen der Vaterschaftsausschlußchance und der Vaterschaftswahrscheinlichkeit wird hingewiesen.
The assumption of prior probability computing the plausibility of paternity by the Essen-Möller equation and its problem
Summary Among objectivists the assumption of firsthand probability, that non-fathers and true-fathers are being given an opinion on with equal frequency, yields to a rejection in calculating the probability of fatherhood according to Essen-Möller. By means of 408 cases it is shown, that this assumption does meet the actual situation. Non-fathers and true-fathers are observed equally frequent. Calculation of fatherhood probability renders a valuable reference to paternity or nonpaternity of a subject in cases of multiple intercourses. These references cannot be brought on by the statement of the exclusion chance of fatherhood based on the mother-child-constellation. The relationship between the exclusion chance and the probability of fatherhood is pointed out.
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3.
We have studied the influence of granulocyte labelling with commercially available 111In-oxine, tropolone (trop) or home made 111In-Mercapto pyridine (Merc) prepared by the method of Thakur (1985) on the cell structure by electron microscopy and on the cell function by enzymatic tests, random migration, chemotaxis, phagocytosis and bactericidal activity. The granulocytes were labelled with 400 Ci 111In-oxine in saline or 111In-trop or Merc in plasma. The effect of the chelating agents with and without addition of the tracer was studied (n=4) with varying concentrations: 5–10 g/ml oxine, 10–160 g/ml trop and 1–4 g/ml Merc. Chemotaxis and random migration were not affected by 111In-trop and clearly supressed by 111In-oxine and Merc; the other tests were normal. The cell structure was disturbed by Merc. The labelling efficiency was excellent with oxine (90%), acceptable with trop (30%–80%) and poor with Merc (10%–25%). Without 111In, chemotaxis and random migration were normal up to a concentration of 80 g/ml trop, 8.5 g/ml oxine and 1 g/ml Merc. With addition of 111In, chemotaxis and random migration were unaffected up to 80 gmg/ml by trop and markedly supressed by Merc and oxine. It is concluded that labelling with 111In-trop assures intact cells.  相似文献   

4.
Radiolabelled 2-Cabomethoxy-3-(4-iodophenyl)tropane (-CIT) has been used in clinical studies for the imaging of dopamine and serotonin transporters with single-photon emission tomography (SPET). 2-Carbomethoxy-3-(4-iodophenyl)nortropane (nor--CIT) is a des-methyl analogue of -CIT, which in vitro has tenfold higher affinity (IC50=0.36 nM) to the serotonin transporter than -CIT (IC50=4.2 nM). Nor--CIT may thus be a useful radioligand for imaging of the serotonin transporter. In the present study iodine-125 and carbon-11 labelled nor--CIT were prepared for in vitro autoradiographic studies on post-mortem human brain cryosections and for in vivo positron emission tomography (PET) studies in Cynomolgus monkeys. Whole hemisphere autoradiography with [125I]nor--CIT demonstrated high binding in the striatum, the thalamus and cortical regions of the human brain. Addition of a high concentration (1 M) of citalopram inhibited binding in the thalamus and the neocortex, but not in the striatum. In PET studies with [11C]nor--CIT there was rapid uptake of radioactivity in the monkey brain (6% of injected dose at 15 min) and high accumulation of radioactivity in the striatum, thalamus and neocortex. Thalamus to cerebellum and cortex to cerebellum ratios were 2.5 and 1.8 at 60 min, respectively. The ratios obtained with [11C]nor--CIT were 20%–40% higher than those previously obtained with [11C]-CIT. Radioactivity in the thalamus and the neocortex but not in the striatum was displaceable with citalopram (5 mg/kg). In conclusion, nor--CIT binds to the serotonin transporter in the primate brain in vitro and in vivo and has potential for PET and SPET imaging of the serotonin transporter in human brain.  相似文献   

5.
Summary A case of sudden unexpected death of a 13-month-old child is reported. The immediate cause of death was aspiration of stomach contents. The autopsy and microscopical examinations revealed cerebral oedema, organ congestion and an increased number of neutrophils in germinal centres of mesenterial lymph nodes and spleen. The finding of ethanol and methanol (5.2 and 0.1) and of significant amounts of a surface-active agent (linear alkyl benzene sulphonate) in the stomach contents indicated consumption of a fluid dish detergent prior to death. The blood ethanol concentration was below 0.1 and urine ethanol and methanol concentrations were 0.28 and 0.04. The possibility that ethanol-containing detergents may trigger hypoglycemic attacks is discussed.  相似文献   

6.
Potassium 38 emits a 2.68-MeV (max) positron, followed promptly by a 2.17-MeV -ray in 99.8% of its disintegrations. A positron is emitted also, followed by a 3.94-MeV -ray, in 0.2% of the decays. The pairs of 511-keV PET±-quanta, which are emitted at 180±0.3° to each other, are in true coincidence with the prompt -rays emitted by the daughter nucleus, within the resolving time of PET instrumentation. Studies made with phantoms by means of a commercial version of the MGH PET camera demonstrated that quantitatively satisfactory images are derived, despite the presence of the prompt -rays. Two-dimensional (2-D) focal-plane images reveal high uptake of38K promptly in the myocardium of dogs, under barbiturate sedation. Third-dimensional (3-D) transverse section PET tomographic images, through four 1.0-cm-thick heart slices orthogonal to the plane of the 2-D images and with 1.4-cm sequential spacing, show38K uptake to be concentrated especially highly in the left ventricle, as expected. Peak levels of activity were observed over the myocardium at 12 s after intravenous bolus injection of ionic38K. Dynamic mode 2-D images were taken at intervals as short as 0.5 s and extending to 1 h.  相似文献   

7.
Positron emission tomography (PET) images are characterized by both poor spatial resolution and high statistical noise. Conventional methods to reduce noise, such as local weighted averaging, produce further deteriorations in spatial resolution, while the use of deconvolution to recover resolution typically amplifies noise to unacceptable levels. We studied the use of two-dimensional Fourier filtering to simultaneously increase quantitative recovery and reduce noise. The filter was based on inversion of the scanner's measured transfer function, coupled with high frequency roll-off. In phantom studies, we found improvements in both hot and cold sphere quantification. Compared with ramp-only filtering, improvements in hot spot recovery for the highest accuracy filter averaged 13.6%±6.6% for spheres larger than 15 mm; improvements in cold spot recovery averaged 30.7%±4.7%. At the same time, the noise was reduced by a factor of 3 compared with ramponly filtering. Fourier-based image restoration filtering is thus capable of improving both accuracy and precision in PET. Correspondence to: J.M. Links  相似文献   

8.
To estimate the radiation dose of ingested 14C- (and 3H-) labelled fatty acids, we measured 14CO2 in samples of expired air in five subjects, and serum 14C activity in four subjects, over 4 weeks. These investigations showed that 25%–40% of ingested 14C-fatty acids were metabolized and expired as 14CO2 within 10 days after ingestion. The residue was expired with a calculated half-life of 493 days. Six days after ingestion of the radiolipids, radioactivity in serum was barely detectable. From these data of 14C-fatty acid metabolism, a total whole-body radiation of 20 mrem/Ci 14C, 8 mrem/Ci14C the first years, was calculated. The corresponding radiation dose for 3H-fatty acid was 2 mrem/Ci 3H and 1 mrem/Ci 3H respectively. Maximal organ-specific radiation (gonads and lungs) from the blood-borne radioactivity was 1 mrem/Ci of 14C-fatty acid.  相似文献   

9.
Human platelets were labelled in the absence or presence of plasma using indium-111 labelled oxine sulphate, tropolone or 2-mercaptopyridine-N-oxide (MPO). Under in vitro and in vivo conditions, platelet functions were evaluated by measuring their aggregability, survival, recovery and early distribution. High labelling efficiency was achieved in saline labelling, whereas with plasma labelling, it was necessary to concentrate the platelet-rich plasma to 4.8 × 106 platelets/l. The aggregation of platelets labelled in plasma or saline was compared with that of controls; platelets labelled in saline showed lower aggregability in 2 M ADP but not in 5 M ADP nor with collagen. No significant differences in platelet survival and recovery were noted between platelets labelled in plasma and those labelled in saline. Our results indicate that partial loss of ADP aggregability in vitro does not influence the in vivo viability of platelets labelled in saline. Scintigraphic studies showed that platelets labelled in a saline medium were temporarily sequestrated in the liver but not in the spleen or heart. Thus, platelet labelling in saline does not affect platelet function adversely, but platelets labelled in plasma are more desirable for assessing the early distribution of platelets in the reticuloendothelial system.  相似文献   

10.
Purpose The purpose of this study was to evaluate the capacity of [11C]6-OH-BTA-1 and positron emission tomography (PET) to quantify -amyloid (A) plaques in the Tg2576 mouse model of Alzheimers disease (AD).Methods PET imaging was performed with the NIH ATLAS small animal scanner in six elderly transgenic mice (Tg2576; age 22.0±1.8 months; 23.6±2.6 g) overexpressing a mutated form of human -amyloid precursor protein (APP) known to result in the production of A plaques, and in six elderly wild-type litter mates (age 21.8±1.6 months; 29.5±4.7 g). Dynamic PET scans were performed for 30 min in each mouse under 1% isoflurane inhalation anesthesia after a bolus injection of 13–46 MBq of [11C]6-OH-BTA-1. PET data were reconstructed with 3D OSEM. On the coronal PET image, irregular regions of interest (ROIs) were placed on frontal cortex (FR), parietal cortex (PA), striatum (ST), thalamus (TH), pons (PO), and cerebellum (CE), guided by a mouse stereotaxic atlas. Time–activity curves (TACs) (expressed as percent injected dose per gram normalized to body weight: % ID-kg/g) were obtained for FR, PA, ST, TH, PO, and CE. ROI-to-CE radioactivity ratios were also calculated. Following PET scans, sections of mouse brain prepared from anesthetized and fixative-perfused mice were stained with thioflavin-S.Results TACs for [11C]6-OH-BTA-1 in all ROIs peaked early (at 30–55 s), with radioactivity washing out quickly thereafter in both transgenic and wild-type mice. Peak uptake in all regions was significantly lower in transgenic mice than in wild-type mice. During the later part of the washout phase (12–30 min), the mean FR/CE and PA/CE ratios were higher in transgenic than in wild-type mice (1.06±0.04 vs 0.98±0.07, p=0.04; 1.06±0.09 vs 0.93±0.08 p=0.02) while ST/CE, TH/CE, and PO/CE ratios were not. Ex vivo staining revealed widespread A plaques in cortex, but not in cerebellum of transgenic mice or in any brain regions of wild-type mice.Conclusion Marked reductions in brain uptake of this radioligand in transgenic mice may be due to reduced cerebral blood flow relative to that in wild-type mice. Specific [11C]6-OH-BTA-1 binding to A plaques, if any, is probably very low, as reflected in the small FR/CE and PA/CE ratio differences. FR/CE and PA/CE ratios are considerably higher in AD patients while A plaque densities in 22-month-old transgenic mice may be expected to show essentially the same density as is observed in the AD brain. This implies that the absence of tracer retention in 22-month-old transgenic mice may be due to the smaller number of A plaque binding sites and/or to lower affinity of the binding sites for [11C]6-OH-BTA-1 as compared with AD patients. [11C]6-OH-BTA-1 shows excellent brain uptake in mice.This work was presented at the 51st Annual Meeting of the Society of Nuclear Medicine in Philadelphia, PA, June 19–23, 2004.  相似文献   

11.
Background Dyspnea and the decrease in arterial saturation in the upright position in elderly subjects is described as platypnea-orthodeoxia syndrome (POS). POS is secondary to the occurrence of an atrial right-to-left shunt through a patent foramen ovale (PFO).Methods This French multicentric study reports on 78 patients (mean age 67±11.3 years) with POS who had transcatheter closure of the PFO; frequently associated diseases were pneumonectomy (n=36) and an ascending aortic aneurysm (n=11). In all patients, the diagnosis was confirmed by transthoracic or/and transesophageal echocardiography. Five different closure devices were used: Amplatz (n=45), Cardioseal (n=13), Sideris (n=11), Das Angel Wings (n=8) and Starflex (n=1). Closure was successful in 76 patients (97%).Results Oxygen saturation increased immediately after occlusion from 84.6±10.7% to 95.1±6.4% (p < 0.001) and dyspnea improved from grade 2.7±0.7 to grade 1±1 (p < 0.001). A small residual shunt was immediately observed in 5 patients (3 with the Cardioseal device, 1 with the Sideris and 1 with the Amplatz) leading to the implantation of a second device in one case (Cardioseal). Two early deaths occurred unrelated to the procedure (one due to sepsis probably related to pneumonectomy, another due to respiratory insufficiency). Other complications were: a small shunt between the aorta and the left atrium, two atrial fibrillations and a left-sided thrombus which disappeared with anticoagulant therapy. At a mean follow-up of 15±12 months, there were 7 late deaths related to the underlying disease.Conclusion Percutaneous occlusion of the foramen ovale is safe and gives excellent results thanks to continuing improvement in available devices. This technique enables some patients in an unstable condition to avoid a surgical closure.  相似文献   

12.
The effects of adrenergic receptor ligands on uptake and storage of the radiopharmaceutical [125I]metaiodobenzylguanidine (MIBG) were studied in the human neuroblastoma cell line SK-N-SH. For uptake studies, cells were incubated for 15 min with varying concentrations of -agonist (clonidine, methoxamine, and xylazine), -antagonist (phentolamine, tolazoline, phenoxybenzamine, yohimbine, and prazosin), -antagonist (proranolol, atenolol), -agonist (isoprenaline and salbutamol), mixed / antagonist (labetalol), or the neuronal blocking agent guanethidine, prior to the addition of [125I]MIBG (0.1 M). The incubation was continued for 2 h and specific cell-associated radioactivity was measured. For the storage studies, cells were incubated with [125I]MIBG for 2 h, followed by replacement with fresh medium with or without drug (MIBG, clonidine, or yohimbine). Cell-associated radioactivity was measured at various times over the next 20 h. Propanolol reduced [125I]MIBG uptake by approximately 30% (P<0.01) at all concentrations tested, most likely due to nonspecific membrane changes. However, incubation with the other -agonists or antagonists failed to elicit significant reductions in uptake. In contrast, all of the -agonists significantly inhibited uptake (P<0.05); guanethidine >xylazine >clonidine=methoxamine. The -antagonists demonstrated a broad range of inhibition (phenoxybenzamine phentolamine prazosin yohimbine=tolazoline)(P<0.05). The mixed ligand, labetalol, inhibited MIBG uptake in a dose-dependent manner with an apparent IC50 of 0.65 M. The retention studies demonstrated that unlabeled MIBG caused profound self-inhibition (P<0.01). Clonidine produced a modest inhibition of retention and yohimbine had no effect. Labetalol, phenoxybenzamine, guanethidine, and propranolol reduced uptake of [125I]MIBG by neuroblastoma cells in culture. Although only labetalol has been reported to cause false-negative MIBG scans, our results suggest that these other drugs have the potential to interfere with MIBG imaging and therapy, particularly at high doses. Adrenergic drugs did not alter cytoplasmic retention of [125I]MIBG in neuroblastoma cells but may have potential in tumors such as phenochromocytoma, where granular storage of MIBG has been observed. Inhibition of [125I]MIBG retention by unlabeled MIBG supports the use of high specific activity radioiodinated MIBG for both diagnosis and therapy.  相似文献   

13.
The parameters of 51Cr labelled red cell survival curves were calculated in 33 patients with homozygous -thalassaemia, 8 with sickle-cell anaemia and 3 with s--thalassaemia, using a non-linear weighted least squares analysis computer program. In thalassaemic children the calculated parameters denote that the shortening of the mean cell life is due to early senescence alone, while there is some evidence that in thalassaemic adults additional extracellular destruction mechanisms participate as well. Red cell survival curves from patients with sickle-cell anaemia and s--thalassaemia resemble each other, while their parameters indicate an initial rapid loss of radioactivity, early senescence and the presence of extracellular red cell destruction factors.N.R.C. Democritos  相似文献   

14.
Imaging of serotonin and dopamine transporters in the living human brain   总被引:2,自引:2,他引:0  
Alterations in brain serotonin (5-HT) and dopamine (DA) activity are associated with several neuropsychiatric disorders, but until now it has not been possible to simultaneously visualize or quantify the 5-HT and the DA transporter density in the living human brain. In this paper we report on the imaging of 5-HT and DA transporters in 28 healthy controls with single-photon emission tomography using iodine-123 labelled 2-carbomethoxy-3-(4-iodophenyl)tropane ([123I]-CIT) as the tracer. The [123I]-CIT distribution showed the most prominent 5-HT activity in the medial frontal cortex, hypothalamus, midbrain and occipital cortex and the greatest DA activity in the basal ganglia. The specific binding of the 5-HT transporters in the medial frontal cortex was 0.377±0.031 and that of the DA transporters in the basal ganglia, 0.916±0.007. Gjedde-Patlak plots indicated two separate components: the first was assumed to represent 5-HT transporters with a slope of 1.29±0.27 h–1 and the second, DA transporters with a slope of 0.30±0.04 h–1. This distinct kinetic pattern and the fact that 5-HT and DA transporters are situated in different parts of the brain provides an opportunity to study in vivo patients suffering from various neuropsychiatric disorders.  相似文献   

15.
The complete removal of a lesion which resembles, or is covered by adjacent tissue may be difficult. Therefore, the capacity of certain lesions to specifically concentrate a radiopharmaceutical has been used to orient progress during surgery. Usually, the measurements of radioactivity in the operative field are carried out by means of small, handy radiation-detecting probes which can be sterilized. Intra-operative nuclear medicine or radionuclide-guided surgery has steadily gained in importance. However, this technique is not being taught. Our study, based on radionuclide-guided surgery of 175 orthopaedic patients suspected of having osteoid osteoma, is well suited to teach the particularities of intra-operative radiation detection, as well as the collaboration between the nuclear physician and the surgeon in the operating theatre.Part of this work was carried out when M.W. and A. S.-A. were at the Saint-Antoine (Paris) and Henri Mondor (Créteil) hospitals respectively.  相似文献   

16.
The skull in homozygous -thalassaemia may present several abnormalities, such as osteopenia, widening of the diploic space, and a hairon-end appearance. In some cases it presents also a particular stratified appearance caused by a variable number of osseous lamellae, parallel with the inner table. This lamellated skull was observed in 16 out of 150 patients affected by the disease (10.6%). Possible mechanisms are discussed. The lamellar osseous changes could be due to repeated periosteal osteoblastic reactions to the sinusoidal neovascularization associated with marrow hyperplasia in poorly transfused patients.  相似文献   

17.
A recent, commercially available computer program for the three-dimensional (3D) display of single-photon emission tomography (SPET) data was used to study myocardial perfusion in patients with coronary artery disease (CAD). To enable the detection of small ischemic lesions, the authors proposed a new distance-subtraction method: after suitable centering of the axial slices, 3D distance-shaded images of the stress study were subtracted from the corresponding views of the rest study. With this technique, small changes in surface-to-observer distance were highlighted, thus enabling us to detect nontransmural ischemic areas of the myocardium. General characteristics and possibilities of the subtraction technique were tested on a simple myocardial phantom. Some clinical results of the application of this method on CAD patients are presented and discussed. In CAD patients in whom only nontransmural ischemic lesions are present, the subtraction of distance-shaded images is decisive for a correct diagnosis.  相似文献   

18.
As a crucial step towards understanding the mechanism of localisation of radiopharmaceuticals in specific target organs, the interaction of the radiopharmaceuticals 99mTc-DMS and 99Tc-DMS with blood serum proteins was studied. The interaction of 99mTc-DMS radiopharmaceutical was examined from two aspects: total protein binding as well as specificity of binding to certain classes of proteins.After in vitro labelling of human sera with 99mTc-DMS, the following values of bound radioactivity to total serum proteins were determined: 65%±3.2% by gel-filtration chromatography; 72%±4.6% by dialysis; while on the basis of precipitation by perchloric and trichloroacetic acid 72.7%±6.8% and 71%±2.3%, respectively. Distribution of 99mTc-DMS or 99Tc-DMS among serum proteins was analysed by agarose gel electrophoresis of the sera at pH 8.6 after in vivo and in vitro labelling of human sera with 99m-Tc-DMS, while the same analysis was performed with 99Tc-DMS complex after in vitro labelling of human and rat sera as well as after in vivo application to the rats.The results obtained demonstrate that carrier serum proteins investigated by agarose gel electrophoresis were in the migration zone of 2-, 1- and 1-globulins, whereas the radioactivity found in the serum albumin zone was negligible. Interaction of both Tc-DMS complexes with proteins was very similar, and this conclusion was in good correlation with our previously obtained results in investigations concerning the biochemical behaviour of these complexes.  相似文献   

19.
Zusammenfassung An 90 Fällen konnte nachgewiesen werden, daß nach Verkehrsunfällen sehr häufig oberhalb der vonWidmark, Jungmichel undKriebs angegebenen Schwankungsbreite liegt.Die beobachtete höhere Ausscheidungsgeschwindigkeit ist wesentlich abhängig von der Höhe der BAK. Bei Konzentrationen um 1,5 und über 2,0 wurden die höchsten Werte för beobachtet.Die Durchschnittswerte für waren nachmittags, kurz nach Mitternacht und in den frühen Morgenstunden höher als zu den übrigen Tageszeiten; entsprechend verhielten sich die Mittelwerte der gefundenen BAK.Die gröten individuellen Schwankungen von fanden sich im 3. und 5. Lebensjahrzehnt.Auf Grund allgemeiner Beobachtungen wird angenommen, daß auer der Höhe der BAK nervöse und hormonale (Insulin) Störungen, die durch erhebliche Erregung ausgelöst werden, als Ursache für die erhöhte Alkoholausscheidung anzusprechen sind.  相似文献   

20.
Summary Authentic car-to-car side collisions (n = 30) with the main impact area at the B-pillar were analyzed to find technical parameters corresponding with the injury severities of the front seat, belt-protected car passengers on the impact side. EES (Energy Equivalent Speed) and Av (delta v, change in velocity) were highly significant predictors of the severity of thoracic and abdominal injuries and total injury severity coded according to the Abbreviated Injury Scale (AIS). At an EES or v 40 km/h all front-seat car passengers on the impact side sustained a total injury severity of Maximum AIS (MAIS) 4 and died. Although a passenger could survive the crash without injury to one or more body regions up to the highest EES- and Av-values, at EES or v 40 km/h fatal injuries were sustained in at least one body region. At an EES 35 km/h or a Av 15 km/h no front-seat car passenger on the impact side remained uninjured.  相似文献   

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