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The radiographic features of Ewing's sarcoma of the bones of the hands and feet are reviewed utilizing cases obtained from the Mayo Clinic patient files and the consultation files of Drs. D.C. Dahlin and K.K. Unni. This series consists of a total of 43 cases of pathologically proven Ewing's sarcoma involving the small bones of the hands and feet. The classic radiographic features of Ewing's sarcoma in the long bones, including lytic, permeative destruction, aggressive periosteal reaction, cortical violation, and a soft tissue mass, are also seen in the bones of the hands and feet, with similar frequency. These classic features are most commonly present in lesions affecting the short tubular bones. Lesions affecting the tarsal bones more often demonstrate atypical radiographic features. These atypical radiographic appearances may play a role in the reported delay in diagnosis of Ewing's sarcoma within the tarsal bones.  相似文献   

3.
Gorham–Stout disease (also known as “disappearing bone disease”) was first described by Jackson in 1838, but was properly defined by Gorham and Stout in a series of 24 patients in 1954–1955. It is a rare disease of unknown etiology (about 200 cases reported in the literature) characterized by spontaneous progressive resorption of bone without malignant proliferation of vascular structures. The diagnosis is one of exclusion and it is based on combined histological, radiological, and clinical features. Benign vascular proliferation with fatty bone marrow and thinning of bony trabeculae is a typical histological feature. Standard radiographs of disappearing bone disease show progressive bony resorption with adjacent soft tissue involvement. Most cases of Gorham–Stout disease resolve spontaneously, but prognosis remains unpredictable. This study reports 13 cases of Gorham–Stout disease treated in our institution from 1968 to 2008. The aim of the work was to review our series and the literature on this rare disease, as well as to evaluate whether or not an optimal treatment can be identified and recommended.  相似文献   

4.
The E1′ center has been used for ESR dating of quartz with assuming that the signal intensity increases with natural radiation dose as those of other ESR signals do. However, this simple assumption is not necessarily correct. Formation and decay of the E1′ center are closely related with its precursor, diamagnetic oxygen vacancies. Gamma ray of large dose (>100 kGy) creates oxygen vacancies giving little dose rate effect, which, therefore, might be useful for dating of granites and high dose dosimetry.  相似文献   

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The abstracts of the joint congress of EANM/WCNMB in Berlin 1998 and of the 45th Annual Meeting of the Society of Nuclear Medicine in Toronto 1998 have been analysed and compared in terms of comprehensibility, composition, questions at issue, methods, patient/subject number, type of conclusion and duplication of information between the meetings. All 1362 and 1096 abstracts, respectively, were analysed from the abstract books with regard to ten "hard" and four "soft" variables. The dominant topics were new radiopharmaceuticals, methods of synthesis, examination methods, evaluation of examinations, investigation algorithms, technical devices and novel use of radiopharmaceuticals. In addition to these topics, there were numerous reports about established radiopharmaceuticals and techniques, often without a specific merit mentioned. There were also many abstracts with questions outside nuclear medicine, but using such techniques. Few papers reported negative findings or dealt with quality assurance, dosimetry, and cost-effectiveness. Many of the conclusions contained hyperbole. Some abstracts were very extensive and detailed. Sixty-seven contributions conveyed identical information at both meetings. Structured and/or paragraphed abstracts promote clarity and reduce the number of lines that need to be read in order to comprehend the background and aim of the abstract. Such contributions were more frequent at the EANM/WCNMB congress while the SNM meeting covered a wider field with a greater representation of radiophysics, instrumentation, and computer evaluations.  相似文献   

7.
Zanetti M 《Skeletal radiology》2008,37(10):875-884
The purpose of this article is to highlight the anatomical variants, technical pitfalls, and the prevalence of abnormal conditions in the asymptomatic population in magnetic resonance imaging of the foot and ankle. Special attention is drawn to the complex anatomy of the deltoid ligament (the superficial tibionavicular ligament, tibiospring ligament, the tibiocalcaneal ligament, and the deep anterior and posterior tibiotalar ligaments) and the posterior tibial tendon insertion including the magic angle artifact and the high prevalence of asymptomatic findings such as "hypertrophied" peroneal tubercle (abnormal only when larger than 5 mm), peroneus quartus (prevalence 17%), and cysts (vascular remnants) just inferior to the angle of Gissane.  相似文献   

8.
《Gait & posture》2006,23(4):317-321
This study compared individual step and averaged spatial and temporal gait parameters measured with an instrumented walkway system (GAITRite®) with a three-dimensional motional analysis system (Vicon-512®). Ten subjects aged 54–83 years (mean 66.5 years) who had undergone knee replacement surgery participated. Subjects walked across the GAITRite® walkway at self-selected comfortable and fast speeds at the same time as the Vicon® system recorded the motion of reflective markers attached to the subjects’ shoes. Walking speed, cadence, step length and step time variables, averaged across one walk for both systems, showed an excellent level of agreement with intra-class correlation coefficients (ICCs) between 0.92 and 0.99 and repeatability coefficients (RCs) between 1.0% and 5.9% of mean values. Step length and step time variables recorded for each footstep also showed good agreement between the systems at both comfortable and fast speeds (ICCs between 0.91 and 0.99; RCs between 2.6% and 7.8%). Frequency distributions showed that individual step values were within 1.5 cm and 0.02 s on the majority (80–94%) of occasions. These data indicate that the GAITRite® system is a valid tool for measuring both averaged and individual step parameters of gait. It is also valid for use in older subjects following knee joint replacement surgery.  相似文献   

9.
An automated variant the of micronucleus assay for erythrocytes in mouse peripheral blood has recently been developed. The flow-cytometric technique used allows very large numbers of erythrocytes to be analysed with a relatively small effort. Here we report the potential of this method to detect a response to extended low-dose-rate exposure to γ-irradiation. The mice were irradiated with a 137Cs source at a dose rate of 4·8 cGy/day for 26 days. Sampling was continued for another 39 days after irradiation. Elevated frequencies compared with the control group were found at days 2, 9 and 20 after the start of the irradiation for micronucleated polychromatic erythrocytes, and at days 9, 20, 29, 42, 51 and 65 for micronucleated normochromatic erythrocytes.  相似文献   

10.
The abstracts of the joint congress of EANM/ WCNMB in Berlin 1998 and of the 45th Annual Meeting of the Society of Nuclear Medicine in Toronto 1998 have been analysed and compared in terms of comprehensibility, composition, questions at issue, methods, patient/subject number, type of conclusion and duplication of information between the meetings. All 1362 and 1096 abstracts, respectively, were analysed from the abstract books with regard to ten ”hard” and four ”soft” variables. The dominant topics were new radiopharmaceuticals, methods of synthesis, examination methods, evaluation of examinations, investigation algorithms, technical devicesand novel use of radiopharmaceuticals. In addition to these topics, there were numerous reports about established radiopharmaceuticals and techniques, often without a specific merit mentioned. There were also many abstracts with questions outside nuclear medicine, but using such techniques. Few papers reported negative findings or dealt with quality assurance, dosimetry, and cost-effectiveness. Many of the conclusions contained hyperbole. Some abstracts were very extensive and detailed. Sixty-seven contributions conveyed identical information at both meetings. Structured and/or paragraphed abstracts promote clarity and reduce the number of lines that need to be read in order to comprehend the background and aim of the abstract. Such contributions were more frequent at the EANM/WCNMB congress while the SNM meeting covered a wider field with a greater representation of radiophysics, instrumentation, and computer evaluations.  相似文献   

11.
The objective of our study is to determine whether 67Ga SPECT can supplement CT and/or MRI diagnostic information by visual comparison of the two separate data sets in patients with head and neck tumors. METHODS: A total of 50 patients with head and neck tumors (benign: 19, malignant: 31) were entered in the study. Three board-certified radiologists who had practical experience in interpreting both head and neck CT/MRI and 67Ga SPECT images, participated as readers. All of the CT and/or MR images of each patient were shown to each reader first, who after they had finished interpreting them were shown the 67Ga SPECT images. They were asked to score each image on a 7-point scale for the likelihood of the presence or absence of malignancy. Histological or cytological evaluation was done in all cases, and the radiologic studies were correlated with these findings. RESULTS: Improvement of all three readers' performance was from 70.7% to 83.3% in the mean accuracy and from 0.790 to 0.921 in the mean Az value (p = 0.033, 0.163, 0.105 in the Az values) after they were shown the 67Ga SPECT images. CONCLUSIONS: 67Ga SPECT should substantially increase confidence in the diagnosis of head and neck tumors when CT and/or MRI do not permit differentiation between benign and malignant disease.  相似文献   

12.
Forensic Toxicology - This study aims to investigate the urinary metabolites of two common α-pyrrolidinophenones (PPs), α-pyrrolidinohexiophenone (α-PHP) and...  相似文献   

13.
AimThe aim of this study was to assess the repeatability and reliability of the S-Plate® pressure platform in a group of healthy subjects.Material and methodsForty subjects, free from physical conditions that would affect normal gait, walked along a five-meter corridor while data were recorded from the pressure platform. A total of 10 steps (five each side) were obtained as well as five static trials; the same measurements were repeated one week later. Peak and mean plantar pressures and contact area were recorded for both dynamic and static trials. Additionally, weight supported on each limb was documented during static trials. To assess intrasession and intersession repeatability and reliability, the intraclass correlation coefficients (ICCs) and coefficient of variation (CoV) were calculated.ResultsTaking the ICC values into account, every static and dynamic variable analysed showed moderate to excellent reliability and the CoV values were all below 12%.ConclusionMeasurements of either static or dynamic plantar pressure variables with the S-Plate® pressure platform show good repeatability and reliability, and so it is useful for comparing steps within and between sessions.  相似文献   

14.
Jan Jirout 《Neuroradiology》1976,10(4):221-223
Summary Significant correlation between the location of the zero zone and spondylosis was found in the cervical spine. The possible role of the zero zone in the development of spondylosis is suggested and the deleterious effect of counteracting forces as compared with a unidirectional traction is stressed.
Die Stelle der Nullzone und ihre Rolle in der Pathogenese der zervikalen Spondylose
Zusammenfassung Die Ergebnisse der dynamischen Studien scheinen darauf hinzuweisen, daß ein Zusammenhang zwischen den häufigsten Stellen der Nullzone und der Spondylose besteht. Es scheint, daß das Bindegewebssystem der Halswirbelsäule auf die Überlastung durch entgegengesetzte Zugkomponenten sehr empfindlich ist und durch diese stärker beschädigt wird als durch eine Traktion, die nur in einer Richtung ausgeübt wird.

Localisation de la zone zero et son rôle dans la pathogenie de la spondylose cervicale
Résumé Il semble y avoir une corrélation entre la zone zéro et le développement d'une spondylose cervicale et que la détérioration discale se fasse spécialement au niveau des mouvements intervertébraux bidirectionnels opposés.


From the annual congress of the European Society of Neuroradiology (Geilo, September 1975)  相似文献   

15.
The components of a 99mTc(Sn)EHDP complex mixture were separated by means of normal pressure and high-pressure anion exchange chromatography, on DEAE-Trisacryl and Aminex, respectively. Precautions were taken to prevent the dissociation of the complexes during chromatography.The charges of the components were determined according to the methods of Wilson and Pinkerton (1985) and Russell and Bischoff (1985).The values of the charges obtained with the two methods are not in agreement.The mean values of the charges obtained with the former method on DEAE-Trisacryl and Aminex disagree. Further, this method does not give correct results for simple ions [Cl, SO42−, Fe(CN)63−].On the other hand, the mean values of the charges obtained with the latter method on DEAE-Trisacryl and Aminex agree, and this method gives the correct charge of SO42−. Thus, Russell and Bischoff's method, in which a reference ion is used, must be preferred.However, even with this method the accuracy of the data obtained is probably limited, due to the difficulty of making corrections for activity coefficients of highly-charged ions at the rather high electrolyte concentrations that must be used in the ion exchange method. So, we think that it is only warranted to conclude that the mean charge of the components of 99mTc(Sn)EHDP is about −6 at pH 7, and that the charges of the individual components are in the range of −4 to −9.The influence of pH and ligand concentration in the reaction mixture was determined with high pressure anion exchange chromatography. It was found that a decrease in the pH of the reaction mixture favours the production of complexes with a long retention time, which leads to a slightly higher mean charge. The ligand concentration of the reaction mixture scarcely influenced the relative concentrations of the components.  相似文献   

16.
The accumulation and microdistribution of uranium in the bone and marrow of Beagle dogs were determined by both neutron activation and neutron‐fission analysis. The experiment started immediately after the weaning period, lasting till maturity. Two animal groups were fed daily with uranyl nitrate at concentrations of 20 and 100?µg?g?1 food. Of the two measuring techniques, uranium accumulated along the marrow as much as in the bone, contrary to the results obtained with single, acute doses. The role played by this finding for the evaluation of radiobiological long‐term risks is discussed. It was demonstrated, by means of a biokinetical approach, that the long‐term accumulation of uranium in bone and marrow could be described by a piling up of single dose daily incorporation.  相似文献   

17.
Summary Allele and genotype frequencies for the HLA-130 locus were determined for use in forensic analyses and paternity tests in Finland. The polymerase chain reaction (PCR) and the reverse dot blot format were employed to detect 6 different HLA-DQ alleles. All 6 HLA-DQ alleles were detected among the 112 unrelated individuals with allele frequencies ranging from 5.8% to 32.6%. The distribution of the observed genotypes is in Hardy-Weinberg equilibrium. Additionally, this Finnish population sample is statistically similar to 2 other Caucasian sample populations. The power of discrimination of this system in the Finnish population sample is 0.92, suggesting this method may prove suitable for identification purposes.  相似文献   

18.
The specific appearance of blood related to time at T1- and T2-weighted spin-echo (SE) sequences is generally accepted; thus, these sequences are classically used for estimating the age of haematomas. Magnetic resonance imaging at 1.5 T, including T1- and T2-weighted SE fluid-attenuated inversion recovery (FLAIR) and T2*-weighted gradient-echo (GE) sequences, was performed on 82 intraparenchymal haematomas (IPHs) and 15 haemorrhagic infarcts (HIs) in order to analyse the appearance at different stages and with different sequences, and to investigate how reliably the age of hematomas can be estimated. The IPHs had been previously detected by CT, were spontaneous (n=72) or traumatic (n=10) in origin and were of different sizes (2 mm to 7 cm) and ages (from 7.5 h to 4 years after acute haemorrhagic event). The age of the lesion was calculated from the moment when clinical symptoms started or the traumatic event occurred. The 15 patients with HIs were patients with ischaemic stroke in whom there was either a suspicion of haemorrhagic transformation on CT, or haemorrhage was detected as an additional finding on MR performed for other indications. Patients with conditions that could affect the SI of blood, such as anticoagulant therapy or severe anaemia, were excluded. The signal intensity pattern of the lesions was analysed and related to their ages without prior knowledge of the clinical data. All lesions were detected with T2*-weighted GE. T1-weighted SE missed 13 haematomas and T2-weighted SE and FLAIR sequences missed five. Haemorrhagic transformation was missed in three infarcts by T1-, T2-weighted SE and FLAIR. The signal pattern on FLAIR was identical to that on T2-weighted SE. For all sequences, a wide variety of signal patterns, without a clear relationship to the age of the haematomas, was observed. There was a poor relationship between the real MR appearance of IPHs and the theoretical appearance on SE sequences. T2*-weighted GE was effective for detecting small bleedings but was not useful for estimating the age of a lesion. The FLAIR does not provide any more information than T2-weighted SE.This work was presented at the XXVIII ESNR congress, in Istanbul, Turkey, September 2003  相似文献   

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