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1.

Background

The purpose of this analysis is to describe the differences in cardiac magnetic resonance characteristics between benign and malignant tumors, which would be helpful for surgical planning.

Methods

This was a prospective cohort study of 130 patients who underwent cardiac magnetic resonance imaging for evaluation of a suspected cardiac mass. After excluding thrombi and tumors without definitive diagnosis, 66 tumors were evaluated for morphologic features and tissue composition.

Results

Of the 66 patients, 39 (59.0%) had malignant tumors and 27 (41.0%) had benign tumors. Patients with malignant tumors were younger when compared with those with benign tumors (age 51 years [42.8-60.0] vs 65 years [60.0-71.0] median). Malignant tumors more often demonstrated tumor invasion (69% vs 0% P < .001) and were more often associated with pericardial effusion (41% vs 7.4% P = .004). Presence of first-pass perfusion (100% vs 33% P < .001) and late gadolinium enhancement (100% vs 59.2%, P < .001) were significantly higher in malignant tumors. In logistic regression modeling, tumor invasion (P < .001) and first-pass perfusion (P < .001) were independently associated with malignancy. Furthermore, using classification and regression tree analysis, we developed a decision tree algorithm to help differentiate benign from malignant tumors (diagnostic accuracy ~90%). The algorithm-weighted cost of misclassifying a malignant tumor as benign was twice that of classifying a benign tumor as malignant.

Conclusions

Our study demonstrates that cardiac magnetic resonance imaging is a useful noninvasive method for differentiating malignant from benign cardiac tumors. Tumor size, invasion, and first-pass perfusion were useful imaging characteristics in differentiating benign from malignant tumors.  相似文献   
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Heterotopic noxious counter‐stimulation (HNCS) inhibits pain and pain processes through cerebral and cerebrospinal mechanisms. However, it is unclear whether HNCS inhibits non‐nociceptive processes, which needs to be clarified for a better understanding of HNCS analgesia. The aim of this study was to examine the effects of HNCS on perception and scalp somatosensory evoked potentials (SEPs). Seventeen healthy volunteers participated in two counter‐balanced sessions, including non‐nociceptive (selective Aβ‐fibre activation) or nociceptive electrical stimulation, combined with HNCS. HNCS was produced by a 20‐min cold pressor test (left hand) adjusted individually to produce moderate pain (mean ± SEM: 42.5 ± 5.3 on a 0–100 scale, where 0 is no pain and 100 the worst pain imaginable). Non‐nociceptive electrical stimulation was adjusted individually at 80% of pain threshold and produced a tactile sensation in every subject. Nociceptive electrical stimulation was adjusted individually at 120% of RIII‐reflex threshold and produced moderate pain (45.3 ± 4.5). Shock sensation was significantly decreased by HNCS compared with baseline for non‐nociceptive (< 0.001) and nociceptive (< 0.001) stimulation. SEP peak‐to‐peak amplitude at Cz was significantly decreased by HNCS for non‐nociceptive (< 0.01) and nociceptive (< 0.05) stimulation. These results indicate that perception and brain activity related to Aβ‐fibre activation are inhibited by HNCS. The mechanisms of this effect remain to be investigated to clarify whether it involves inhibition of spinal wide‐dynamic‐range neurons by diffuse noxious inhibitory controls, supraspinal processes or both.  相似文献   
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The co-occurrence of Diogenes and Capgras syndromes, both unusual in themselves, would be expected to be rare. A MEDLINE search using the terms Diogenes, Capgras, self-neglect and domestic squalor revealed no previous reports of this combination of disorders. Both conditions are somewhat dubiously named as &#164 syndromes' when in fact they are probably no more than symptoms with different causes. Of particular interest in this case is the exacerbation of the self-neglect, characteristic of the Diogenes syndrome, by the delusional misidentification which marks the Capgras syndrome; as well as the reinforcement of the previously recognised association with frontal lobe pathology. The role of medication, though limited, is described. ( Int J Psych Clin Pract 2001; 5:75-76)  相似文献   
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We determine the effect of nano copper on visceral organs and contents of trace elements in organs and serum in weanling pigs. Our results showed that following supplementary concentration with 25, 50 and 200?mg/kg/day of nano copper, contents of copper shows trend of increasing in liver, kidney and intestinal; and ferrum shows gradually decreasing. The histopathological examination showed hemolysis, degeneration, nucleus pycnosis in liver, while renal tubular epithelial cell exfoliation and lymphocyte infiltration were found in kidney on supplementation of high concentration of nano-copper. Therefore, dietary supplementation of nano-copper 25?mg/kg b.wt could be a potential substitute for weaning piglets.  相似文献   
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Depressive symptoms are associated with an increased risk of death, but most of this association remains unexplained. Our aim was to explore the contribution of sleep duration and disturbances to the association between depressive symptoms, all‐cause and cardiovascular disease mortality. A total of 5813 (4220 men and 1593 women) aged 50–74 years at baseline, participants of the British Whitehall II prospective cohort study, were included. Depressive symptoms, sleep duration and disturbances were assessed in 2003–04. Mortality was ascertained through linkage to the national mortality register until August 2012, with a mean follow‐up of 8.8 years. Depressive symptoms were associated with an increased risk of mortality from all causes [hazard ratio (HR) = 1.51; 95% confidence interval (CI): 1.16–1.97)] and cardiovascular diseases (HR = 1.63; 95% CI: 1.01–2.64) after adjustment for sociodemographic characteristics. Further adjustment for sleep duration and disturbances reduced the association between depressive symptoms and cardiovascular mortality by 21% (HR = 1.53; 95% CI: 0.91–2.57). Sleep seems to have a role, as a mediator or confounder, in explaining the association between depressive symptoms and cardiovascular mortality. These findings need replication in larger studies with longer follow‐up.  相似文献   
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