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排序方式: 共有602条查询结果,搜索用时 10 毫秒
1.
Simona Ben-Haim Ela Kupzov Ada Tamir Alex Frenkel Ora Israel 《Journal of nuclear cardiology》2006,13(6):791-800
BACKGROUND: Fluorine 18 fluorodeoxyglucose (FDG) uptake may be increased in atherosclerotic plaques in asymptomatic patients. Repeat positron emission tomography (PET)/computed tomography (CT) studies were assessed for changes in patterns of FDG uptake and CT calcifications. METHODS AND RESULTS: Fifty consecutive cancer patients (mean age, 68 +/- 8 years) had repeat PET/CT studies 8 to 26 months apart. PET, CT, and PET/CT images were retrospectively evaluated for vascular wall abnormalities and for interval changes in the thoracic and abdominal aortas, as well as in carotid and iliac arteries, classified as PET+/CT+, PET+/CT-, and PET-/CT+. There were 485 abnormal sites in the first study and 495 in the second. CT calcifications were found in 46 patients (92%) in the first study and in 47 (94%) in the second. Vascular wall FDG uptake was found in both studies in 37 patients (74%). The pattern changed in 57 of 119 PET+ sites (48%) in the second study compared with 15 of 366 PET- sites (4%) (P < .0001). In the second study new PET+ sites were observed in 36 of 111 sites (32%) versus new PET-/CT+ sites in 19 of 384 sites (5%) (P < .0001). CONCLUSIONS: Changes in vascular FDG activity and CT calcifications can be assessed by repeat PET/CT. FDG-avid foci may represent a dynamic process, transient inflammation, whereas CT calcifications may indicate stable atherosclerosis. These preliminary results support the need for further research. 相似文献
2.
Is 18F-FDG PET/CT useful for imaging and management of patients with suspected occult recurrence of cancer? 总被引:5,自引:0,他引:5
Ora Israel Maya Mor Luda Guralnik Nirit Hermoni Diana Gaitini Rachel Bar-Shalom Zohar Keidar Ron Epelbaum 《Journal of nuclear medicine》2004,45(12):2045-2051
Rising serum tumor markers may be associated with negative imaging in the presence of cancer. CT and (18)F-FDG PET may yield incongruent results in the assessment of tumor recurrence. The present study evaluates the incremental role of (18)F-FDG PET/CT for the diagnosis and management of cancer patients with increasing levels of tumor markers as the sole indicator of potential recurrence after initial successful treatment. METHODS: Thirty-six cancer patients with increasing levels of tumor markers during follow-up and negative CT underwent (18)F-FDG PET/CT, which showed 111 sites of increased tracer uptake. PET/CT was compared with PET results on a site-based analysis for characterization of (18)F-FDG foci and on a patient-based analysis for diagnosis of recurrence. The clinical impact of PET/CT on further patient management was evaluated. RESULTS: Thirty patients (83%) had recurrence in 85 malignant sites (77%). For the site-based analysis, PET had a sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of 96%, 50%, 85%, 85%, and 82%, respectively, as compared with the performance indices of PET/CT of 100%, 89%, 97%, 97%, and 100%, respectively. There was a statistically significant difference between the specificity (P < 0.05) and accuracy (P < 0.001) of PET and PET/CT for precise characterization of suspected lesions. For the patient-based analysis, PET had a sensitivity, specificity, and accuracy of 93%, 50%, and 86%, respectively, as compared with PET/CT with values of 93%, 67%, and 89%, respectively (P = not significant). PET/CT was the single modality that directed further management and treatment planning in 12 patients (33%). CONCLUSION: The results of this study indicate that PET/CT may improve the accuracy of occult cancer detection and further lead to management changes in patients with increasing levels of tumor markers as the sole suspicion of recurrent malignancy. 相似文献
3.
Joseph Levine Mirtha Gonsalves Izak Babur Shaul Stier Avner Elizur Ora Kofman R. H. Belmaker 《Human psychopharmacology》1993,8(1):49-53
Inositol is an important precursor for second messenger synthesis and has been reported to be reduced by lithium treatment in rat brain and in human CSF in depression. An open trial of 6 g/day in 11 depressed patients resistant to previous treatment led to major improvement in nine patients. The enzyme synthesizing inositol has been reported to be elevated in schizophrenia, suggesting an attempted compensation for possible inositol deficiency. A controlled double-blind crossover trial in 10 chronic schizophrenic patients of 6 g/day of inositol for 30 days did not reveal any benefit. 相似文献
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Metal-on-metal (MoM) bearings for total hip arthroplasty (THA) have come under scrutiny with reports of high failure rates. Clinical outcome studies with several commercially available MoM THA bearings remain unreported. We evaluated 78 consecutive MoM THAs from a single manufacturer in 68 patients. Sixty-six received cobalt–chrome (CoCr) monoblock and 12 received modular titanium acetabular cups with internal CoCr liners. Femoral components were titanium with modular necks. At average 2.1 years postoperatively, 12 THAs (15.4%) demonstrated aseptic failure (10 revisions, 2 revision recommended). All revised hips demonstrated capsular necrosis with positive histology reaction for aseptic lymphocytic vasculitis-associated lesions/adverse local tissue reactions. Prosthetic instability following revision surgery was relatively common. Female gender was a strong risk factor for failure, though smaller cups were not. Both monoblock and modular components fared poorly. Corrosion was frequently observed around the proximal and distal end of the modular femoral necks. 相似文献
6.
In this paper, we present a series of studies performed in the last decade that examined the contribution of e-books reading to the language and literacy of young Hebrew-speaking children. Children worked with two e-books designed by the researchers to achieve this aim. We present the effect of reading these e-books on the language and literacy of young children: (a) in general, (b) in different socio-economic statues (SES) groups, (c) among children at risk for learning disabilities (ALD). Language progress was measured by phonological awareness, word meaning, story production and comprehension, and literacy progress was measured by letter naming, word reading and word writing. Results showed that the e-book reading supported all language and literacy skills, except letter naming. The progress of most skills appeared after three reading sessions. Children from middle- and low-SES families benefited from reading the e-books and in some cases, low-SES children were contributed more than those from a middle SES. ALD children improved their vocabulary, phonological awareness and concept about print when provided with an educational e-book. Further research and pedagogical implications for software developers and educators are discussed. 相似文献
7.
This study longitudinally assessed associations between secure and ambivalent attachment with mothers, fathers and professional caregivers in infancy, and personal space regulation and perceived interpersonal competence in 64 early adolescents (31 boys, 33 girls). Children classified as ambivalently attached to their mothers and/or professional caregivers in infancy displayed significantly larger permeability of personal space as compared with children classified as securely attached. Attachment classifications with fathers were not associated with personal space behavior at 12 years of age. Children who had an insecure attachment relationship with both the mother and the professional caregiver in infancy displayed smaller personal space boundaries, and tolerated larger intrusions into their personal space as compared with children who had two secure attachments in infancy. Finally, perceived interpersonal competence was positively correlated with personal space permeability. 相似文献
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9.
Victor A. Aniol Aleksandra Y. Ivanova-Dyatlova Ora Keren Alla B. Guekht Yosef Sarne Natalia V. Gulyaeva 《Epilepsy & behavior : E&B》2013,26(2):196-202
According to different studies, between 5% and 10% of people suffer a single isolated seizure episode at some time in their life. However, little is known about the effects of a single seizure episode on cognitive function, and clinical investigations of this issue are not easy to perform. In this situation, animal models may be a reasonable choice. The aim of our study was to follow the time course of delayed effects of generalized clonic-tonic convulsions on learning and memory functions in rats. A clonic-tonic seizure episode was induced by a single i.p. injection of pentylenetetrazole (70 mg/kg). Different behavioral tests were performed between days 10 and 100 after the convulsant administration. A single seizure episode resulted in a gradual decline in short-term memory function as assessed by novel object recognition and social recognition tests. The seizure episode induced a quick increase in hippocampal cell proliferation; however, the excessive newly generated cells seemed to be eliminated by the time of obvious cognitive impairment. These observations are indicative of a slowly developing and long-lasting influence of a single seizure episode on cognitive function. A rather long time period between the seizure episode and the manifestations of cognitive decline provides a window for a possible therapeutic intervention, and an elaboration of such “post-conditioning” treatments may be a promising opportunity to prevent subsequent mental impairments in patients. 相似文献
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