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Imaging of neuroendocrine tumors: accuracy of helical CT versus SRS   总被引:5,自引:0,他引:5  
Background: We retrospectively compared the accuracy of somatostatin receptor scintigraphy (SRS) with that of helical computed tomography (CT) in the detection and localization of primary and metastatic neuroendocrine tumors.Methods: A medical record search identified 27 patients with known or clinically suspected neuroendocrine tumors who underwent helical CT and SRS within 3 months of one another at our institution. CT images were evaluated retrospectively by two blinded radiologists who used consensus reading. Images were evaluated for the presence or absence of primary tumor and hepatic and extrahepatic metastases. CT results were compared with the SRS report as interpreted by the nuclear medicine physicians. The results of the surgical, clinical follow-up, and pathologic findings were considered as the gold standard. Sensitivity, specificity, and accuracy were calculated for both imaging techniques. In addition, McNemar analysis was performed to determine statistically significant differences between CT and SRS.Results: Helical CT was more sensitive than SRS in the detection of extrahepatic metastases, and the difference between the two imaging modalities was statistically significant (p = 0.0312) as determined by the McNemar chi-square test. However, the difference between CT and SRS in detecting primary neuroendocrine tumors, hepatic metastasis, and combined hepatic and extrahepatic metastasis was not statistically significant (p = 0.625, 1.000, and 1.000, respectively).Conclusion: Helical CT and SRS have similar sensitivity, specificity, and accuracy in detecting primary neuroendocrine tumor and hepatic metastasis. However, helical CT appears to be more sensitive in detecting extrahepatic metastasis from primary neuroendocrine tumors.  相似文献   
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Evidence of the association between 25-hydroxyvitamin D (25(OH)D) and metabolic syndrome (MeS) remains uncertain and incongruent. This study aimed to determine the association between 25(OH)D and MeS among Jordanian adults. A complex multistage sampling technique was used to select a national population-based household sample. The present report deals exclusively with adults aged > 18 years who had complete information on all components of MeS (n = 3,234). A structured questionnaire was used to collect all relevant information. Anthropometric, clinical, and laboratory measurements were obtained. MeS was defined according to the International Diabetes Federation (IDF) definition. Of the total, 42.0% had MeS and 31.7% had 25(OH)D < 30 ng/ml. In a stratified analysis, the prevalence of MeS did not differ significantly between subjects with low and normal 25(OH)D levels for men and women in all age groups. In the multivariate analysis, the odds of MeS were not significantly different between subjects with low and normal 25(OH)D levels (OR = 0.85, 95% CI: 0.70, 1.05, P-value = 0.133). The association between 25(OH)D and MeS remained non-significant when 25(OH)D was analyzed as a continuous variable (OR = 1.004, 95% CI; 1.000, 1.008, P = 0.057) and when analyzed based on quartiles. None of the individual components of MeS were significantly associated with 25(OH)D level. This study does not provide evidence to support the association between 25(OH)D level and MeS or its individual components. Prospective studies are necessary to better determine the roles of 25(OH)D levels in the etiology of MeS.  相似文献   
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Background  

Despite impressive progress in the science and technology of reproduction, the mechanism by which labour is initiated in humans remains obscure.  相似文献   
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Scorpion envenoming is less studied during gestation; however, it may induce various biological disturbances in maternal organism and hypothetical ones on their fetuses. The scope of this report was to elucidate some biological effects of such poisoning in late pregnant rats. Hence, TBARS levels in maternal lung, placental and fetal pulmonary and hepatic tissues and dam's biochemical blood parameters (glucose, creatinine, 17-β estradiol, progesterone, blood nitrogen urea, sodium and potassium maternal plasma concentrations) had been evaluated after saline (G1), and scorpion venom (G2: 30 min and G3: 60 min) injections in 22nd day pregnant rats. Histological microscopic examination of these tissues was also carried out in HE-stained paraffin sections. In addition, the mean arterial blood pressure following the envenomation variations was measured in three rats from the same pool. Our results showed that Buthus occitanus tunetanus crude venom induced significant increase in maternal, placental and fetal tissues lipid peroxidation, concomitant with blood pressure elevation. Maternal plasma creatinine, estradiol and progesterone concentrations levelled up significantly after 30 min or later (60 min) after the venom injection. Except for a probable pronounced oedema and few congestions in maternal lungs and degenerative aspects of trophoblast cells, all examined tissues showed a conserved structure. These results suggest that scorpion envenomation may induce gestation process disturbances and threatens both mother's and fetus’ well-being.  相似文献   
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108.

Background  

Obesity became major health problem in the world, the objective of this work was to examine the effect of high sucrose and high fat diet to induce obesity on antioxidant defense system, biochemical changes in blood and tissue of control, non treated and treated groups by administration of Garcinia cambogia, and explore the mechanisms that link obesity with altered renal function  相似文献   
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