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排序方式: 共有724条查询结果,搜索用时 31 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
4.
Tursun B Schlüter A Peters MA Viehweger B Ostendorff HP Soosairajah J Drung A Bossenz M Johnsen SA Schweizer M Bernard O Bach I 《Genes & development》2005,19(19):2307-2319
LIM kinase 1 (LIMK1) controls important cellular functions such as morphogenesis, cell motility, tumor cell metastasis, development of neuronal projections, and growth cone actin dynamics. We have investigated the role of the RING finger protein Rnf6 during neuronal development and detected high Rnf6 protein levels in developing axonal projections of motor and DRG neurons during mouse embryogenesis as well as cultured hippocampal neurons. RNAi-mediated knock-down experiments in primary hippocampal neurons identified Rnf6 as a regulator of axon outgrowth. Consistent with a role in axonal growth, we found that Rnf6 binds to, polyubiquitinates, and targets LIMK1 for proteasomal degradation in growth cones of primary hippocampal neurons. Rnf6 is functionally linked to LIMK1 during the development of axons, as the changes in axon outgrowth induced by up- or down-regulation of Rnf6 levels can be restored by modulation of LIMK1 expression. Thus, these results assign a specific role for Rnf6 in the control of cellular LIMK1 concentrations and indicate a new function for the ubiquitin/proteasome system in regulating local growth cone actin dynamics. 相似文献
5.
6.
The market for pharmacoeconomic analysis is rapidly expanding. Demand for experienced investigators seems to have outpaced the capacity of both the academic community and industry to train qualified practitioners. The result is that many professionals charged with producing and using cost-effectiveness and other drug-related economic evaluation studies may lack the basic skills required to carry out their duties. This, in turn, raises concerns regarding the credibility and integrity of the field as a whole. In our opinion, the adoption of self-imposed practice guidelines is a necessary first step in confronting these issues. However, the power of guidelines to promote responsible practice will be limited by the technical preparation of the analysts charged with adhering to them. A long term solution requires a collaborative commitment, on the part of both the academic community and the private sector, to targeted graduate training in pharmacoeconomic methods, and to the provision of ample opportunities for continuing professional education. 相似文献
7.
Abraham Benshushan Orly Shoshani Ora Paltiel Joseph G. Schenker Aby Lewin 《Journal of assisted reproduction and genetics》1997,14(6):347-353
Purpose: Our purpose was to measure changes in semen quality and quantity in young healthy sperm donors in Jerusalem over time.
Methods: A retrospective analysis of semen parameters over 15 years using linear regression analysis, in a single sperm bank in a
tertiary university center. Study population consisted of 188 young, healthy medical students, aged 20 to 30 years, who donated
sperm samples for Artificial insemination between 1980 and 1995.
Results: There were no statistically significant changes in semen concentration and motility during the study period. The mean semen
volume increased by 0.1 ml (5.1%) per year (P < 0.0001), with a concomitant mean rise of 5.8 × 106 (7.7%) per year in total motile sperm count. The percentage normal morphology decreased by a mean of 1.04% per year during
the entire period (P < 0.0001).
Conclusions: During the past 15 years, there has been an increase in total motile sperm count, secondary to an increase in semen volume,
and a decline in normal morphology that are independent of the age and the duration of abstinence in fertile men. 相似文献
8.
9.
Gabay Zarina Paltiel Gondwe Kaboni Whitney Topaz Maxim 《Maternal and child health journal》2022,26(6):1273-1273
Maternal and Child Health Journal - 相似文献
10.
According to the hypersensitive behavioral approach system (BAS) model of bipolar disorder (BP), hypersensitivity of the BAS is a trait that should be present even in the euthymic state. This would be expected to result in increased anger and reward sensitivity, both of which are related to the approach system. This study examined these predictions through the use of tasks that assess different aspects of the BAS: reward sensitivity, anger and impulsivity. These characteristics were assessed using the probabilistic classification task (PCT), ultimatum game (UG) and single key impulsivity paradigm (SKIP), respectively. Participants were euthymic adult bipolar disorder patients (BP; N=40) and healthy controls (HC; N=41). In the UG, all participants showed the standard pattern of rejecting overtly unfair offers and accepting clearly fair offers; however, BPs rejected more of the moderately unfair offers than did HCs. BP and HC participants did not differ on their ability to learn, but did show different patterns of learning from reward and punishment. Learning for reward and punishment were negatively correlated in the BP group, suggesting that individuals could learn well either from reward or punishment, but not both. No correlation was found between these forms of learning in the HC group. BP patients show signs of their disorder even in the euthymic state, as seen by the dysbalance between reward and punishment learning and their residual anger in the UG. 相似文献