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1.
Summary Contusions and lacerations of the frontal lobes are very frequent; 43.4% in the whole series of traumatic brain mass lesions. Clinical, ICP, CT scan data and neuropathological findings in patients with such lesions are analysed and correlated. Moreover, the clinical features and the outcome of frontal masses undergoing surgery are also compared with similar lesions located in the temporal lobes.Frontal lesions cannot be differentiated on purely clinical grounds and the factors governing the outcome in both locations are the same. On the whole, surgical indications nowadays seem to be rather rare; only lesions behaving truly as expanding lesions with obvious intracranial hypertension benefiting from surgery.Brain contusion-laceration syndromes in general can no longer be considered separate entities. Neither should they be included in the miscellaneous group of traumatic intracranial mass lesions, since the pathophysiological significance of purely extracerebral effusions is entirely different.Traumatic contusions and lacerations and/or intracerebral haematomas, whether frontal or located elsewhere, should, instead, be considered in the context of head injuries of a different degree of gravity, as having collateral features which, on occasion, may call for surgical management.  相似文献   
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To determine the correlation of quantitative assessment of coronary narrowings with left ventricular functional impairment induced by exercise, 57 patients with 1-vessel coronary artery disease and without evidence of collateral flow were studied. A significant relation was observed between minimal cross-sectional area, percent area stenosis, minimal lumen diameter, percent diameter stenosis and the percentage of segmental area change from rest to peak exercise in a vascular distribution territory (r = 0.76, p less than 0.001; r = -0.55, p less than 0.001; r = 0.56, p less than 0.001; r = -0.75, p less than 0.001, respectively). For minimal cross-sectional area, the best cut-off value to separate significantly patients who had a decrease in contractility at peak exercise testing from those who had a normal response was 2 mm2 (p less than 0.001); for percent cross-sectional area stenosis, it was 75% (p less than 0.001); for minimal lumen diameter, it was 0.7 mm (p less than 0.001); and, for percent diameter stenosis, it was 85% (p less than 0.001). High cut-off values for angiographic variables are necessary to separate significantly patients who have a decrease in contractility at peak exercise testing from those who have a normal response. Several patients with mild coronary stenoses may have either normal or abnormal wall motion during exercise. Thus, exercise echocardiography is a useful tool in detecting the presence of fairly severe anatomic narrowing, whereas it is of limited clinical use in the assessment of intermediate coronary atherosclerotic lesions.  相似文献   
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Previously, it was shown that the type 1 deiodinase (D1) is subject to substrate-dependent inactivation that is blocked by pretreatment with the inhibitor of D1 catalysis, propylthiouracil (PTU). Using HepG2 cells with endogenous D1 activity, we found that while considerable D1-mediated catalysis of reverse tri-iodothyronine (rT(3)) is observed in intact cells, there was a significant loss of D1 activity in sonicates assayed from the same cells in parallel. This rT(3)-mediated loss of D1 activity occurs despite no change in D1 mRNA levels and is blocked by PTU treatment, suggesting a requirement for catalysis. Endogenous D1 activity in sonicates was inactivated in a dose-dependent manner in HepG2 cells, with a ~50% decrease after 10?nM rT(3) treatment. Inactivation of D1 was rapid, occurring after only half an hour of rT(3) treatment. D1 expressed in HEK293 cells was inactivated by rT(3) in a similar manner. (75)Se labeling of the D1 selenoprotein indicated that after 4?h rT(3)-mediated inactivation of D1 occurs without a corresponding decrease in D1 protein levels, though rT(3) treatment causes a loss of D1 protein after 8-24?h. Bioluminescence resonance energy transfer studies indicate that rT(3) exposure increases energy transfer between the D1 homodimer subunits, and this was lost when the active site of D1 was mutated to alanine, suggesting that a post-catalytic structural change in the D1 homodimer could cause enzyme inactivation. Thus, both D1 and type 2 deiodinase are subject to catalysis-induced loss of activity although their inactivation occurs via very different mechanisms.  相似文献   
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The goal of this paper is to describe the baseline characteristics of Live Well (intervention to prevent weight gain in recent immigrant mother–child dyads from Brazil, Haiti, and Latin America) participants, and to explore self-reported changes in diet and physical activity post-immigration. Baseline data from 383 mothers were used for this study. Dyads attended a measurement day where they completed self-administered surveys collecting information about socio-demographics, diet, physical activity, other psychosocial variables, and height and weight. Haitian mothers’ socio-demographic profile differed significantly from that of Brazilians’ and Latinas’: they have been in the US for a shorter period of time, have higher rates of unemployment, are less likely to be married, more likely to have ≥3 children, more likely to be obese, and have immigrated for family or other reasons. In multivariate models, self-reported changes in diet and physical activity since migrating to the US were significantly associated with BMI with non-linear relationships identified. Future research is needed to understand how diet and physical activity change while acculturating to the US and explore the adoption of both healthy and unhealthy dietary changes.  相似文献   
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Ozonized autohemotransfusion has been used as a complementary therapy in patients with peripheral arterial disease (PAD). To determine whether ozone therapy could acutely modify artery vasodilatory capacity, a flow-mediated dilation test was performed at the brachial artery level before and after an ozonized autohemotransfusion in 16 patients with PAD, mean (± SD) age 55±1.8 years, and 14 healthy volunteers matched for age, sex and body mass index. Before ozonized autohemotransfusion, the mean baseline diameter of the brachial artery was higher in PAD patients than in healthy subjects (4.6±0.54 mm versus 3.6±0.54 mm, P<0.001) while mean flow-mediated brachial artery dilation and percentage of increase in flow were significantly lower in PAD patients than in controls (6.3±6.1% versus 11.8±2.4%, P<0.02; 433±61% versus 580±46%, P<0.02, respectively). No significant changes were observed after ozonized autohemotransfusion, indicating that ozonized autohemotransfusion does not modify endothelium-dependent ischemia-induced vascular reactivity.  相似文献   
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Purpose

To compare the performance of PET/MRI imaging using MR attenuation correction (MRAC) (DIXON-based 4-segment -map) in breast cancer patients with that of PET/CT using CT-based attenuation correction and to compare the quantification accuracy in lesions and in normal organ tissues.

Methods

A total of 36 patients underwent a whole-body PET/CT scan 1 h after injection and an average of 62 min later a second scan using a hybrid PET/MRI system. PET/MRI and PET/CT were compared visually by rating anatomic allocation and image contrast. Regional tracer uptake in lesions was quantified using volumes of interest, and maximal and mean standardized uptake values (SUVmax and SUVmean, respectively) were calculated. Metabolic tumor volume (MTV) of each lesion was computed on PET/MRI and PET/CT. Tracer uptake in normal organ tissue was assessed as SUVmax and SUVmean in liver, spleen, left ventricular myocardium, lung, and muscle.

Results

Overall 74 FDG positive lesions were visualized by both PET/CT and PET/MRI. No significant differences in anatomic allocation scores were found between PET/CT and PERT/MRI, while contrast score of lesions on PET/MRI was significantly higher. Both SUVmax and SUVmean of lesions were significantly higher on PET/MRI than on PET/CT, with strong correlations between PET/MRI and PET/CT data (ρ = 0.71–0.88). MTVs of all lesions were 4% lower on PET/MRI than on PET/CT, but no statistically significant difference was observed, and an excellent correlation between measurements of MTV with PET/MRI and PET/CT was found (ρ = 0.95–0.97; p < 0.0001). Both SUVmax and SUVmean were significantly lower by PET/MRI than by PET/CT for lung, liver and muscle, no significant difference was observed for spleen, while either SUVmax and SUVmean of myocardium were significantly higher by PET/MRI. High correlations were found between PET/MRI and PET/CT for both SUVmax and SUVmean of the left ventricular myocardium (ρ = 0.91; p < 0.0001), while moderate correlations were found for the other normal organ tissues (ρ = 0.36–0.61; p < 0.05).

Conclusions

PET/MRI showed equivalent performance in terms of qualitative lesion detection to PET/CT. Despite significant differences in tracer uptake quantification, due to either methodological and biological factors, PET/MRI and PET/CT measurements in lesions and normal organ tissues correlated well. This study demonstrates that integrated whole-body PET/MRI is feasible in a clinical setting with high quality and in a short examination time.  相似文献   
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Colitis cystica profunda is a rare intestinal lesion. Because of its clinical expression (rectorrhagia, mucorrhea and abdominal pain) and the way it appears to current imaging techniques this disease presents features which can be associated with colon neoplasm. Its diagnosis has to be confirmed histologically, and its etiology remains unclear. The following is a case report of colitis cystica profunda recurring 20 years after a first episode in a white woman, who had had an anterior resection of the sigmoid colon and upper rectum to deal with a colitis cystica profunda-induced stenosis of the sigmoid colon and at 41 underwent the transanal removal of a polypoid lesion. A review of 20 cases in the literature showed that colitis cystica profunda has a predilection for the male and generally affects the medial and lower rectum and the sigmoid colon. The literature also confirmed the association with ulcerative rectocolitis, Crohn's disease and rectal prolapse. The type of treatment varies from surgical, medical, and endoscopic to no treatment at all.  相似文献   
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