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22.

Purpose:

To evaluate the use of a T2‐weighted SPACE sequence (T2w‐SPACE) to assess carotid stenosis via several methods and compare its performance with contrast‐enhanced magnetic resonance angiography (ceMRA).

Materials and Methods:

Fifteen patients with carotid atherosclerosis underwent dark blood (DB)‐MRI using a 3D turbo spin echo with variable flip angles sequence (T2w‐SPACE) and ceMRA. Images were coregistered and evaluated by two observers. Comparisons were made for luminal diameter, luminal area, degree of luminal stenosis (NASCET: North American Symptomatic Endarterectomy Trial; ECST: European Carotid Surgery Trial, and area stenosis), and vessel wall area. Degree of NASCET stenosis was clinically classified as mild (<50%), moderate (50%–69%), or severe (>69%).

Results:

Excellent agreement was seen between ceMRA and T2w‐SPACE and between observers for assessment of lumen diameter, lumen area, vessel wall area, and degree of NASCET stenosis (r > 0.80, P < 0.001). ECST stenosis was consistently higher than NASCET stenosis (48 ± 14% vs. 24 ± 22%, P < 0.001). Area stenosis (72 ± 2%) was significantly higher (P < 0.001) than both ESCT and NASCET stenosis.

Conclusion:

DB‐MRI of carotid arteries using T2w‐SPACE is clinically feasible. It provides accurate measurements of lumen size and degree of stenosis in comparison with ceMRA and offers a more reproducible measure of ECST stenosis than ceMRA. J. Magn. Reson. Imaging 2012;449‐455. © 2011 Wiley Periodicals, Inc.  相似文献   
23.
Endothelial dysfunction is an important factor leading to atherosclerosis, hypertension and heart failure. Flow mediated dilatation (endothelium dependent function) can be evaluated by vascular ultrasound. We investigated 71 heart failure patients (36 men-50.7%, 35 women-49.3%). The evaluation methods were: electrocardiogram, vascular ultrasound, echocardiography, chest X ray, hematological and biochemical tests. The statistical correlations were performed between clinical data, morphologic and hemodynamic parameters. Our results showed that endothelial dysfunction was present in all heart failure patients but it did not correlate with hemodynamic parameters. Elastic arterial parameters variation correlated with heart failure severity and flow mediated vasodilation.  相似文献   
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AIM:To investigate the small bowel of seronegative spondyloarthropathy(SpA) patients in order to ascertain the presence of mucosal lesions.METHODS:Between January 2008 and June 2010,54 consecutive patients were enrolled and submitted to avideo capsule endoscopy(VCE) examination.Historyand demographic data were taken,as well as the history of non-steroidal anti-inflammatory drug(NSAID) consumption.After reading each VCE recording,a capsule endoscopy scoring index for small bowel mucosal inflammatory change(L...  相似文献   
27.
To determine whether the decreased rate of restenosis observed with drug-eluting stents (DES) has changed the treatment of patients with recurrent symptoms after stent placement, we compared patients hospitalized with presumed cardiac symptoms within 1 year after placement of either a DES or a bare metal stent (BMS). In this retrospective, single-center study, cases were identified from consecutive patients who received a DES from March 2003 to July 2004 or a BMS from August 2001 to June 2002. No differences were noted in the rate of hospitalization, hospitalization for presumed cardiac symptoms, use of coronary angiography in patients hospitalized for presumed cardiac symptoms, or average interval to hospitalization. In contrast, restenosis and the need for additional revascularization procedures were higher in the BMS group. The primary indication for additional revascularization was restenosis in the BMS group and progression of coronary artery disease in the DES group. In the DES group, the need for revascularization was significantly higher in patients with multi- versus single-vessel coronary artery disease (26% vs 7%, p < 0.05). In conclusion, the rate of hospitalization and use of coronary angiography in patients with recurrent symptoms were similar in patients who received a BMS or DES, despite the decreased rates of restenosis and additional revascularization procedures observed with DESs.  相似文献   
28.
Hypophosphatasia is caused by deficiency of activity of the tissue-nonspecific alkaline phosphatase (TNSALP), resulting in a defect of bone mineralization. Enzyme replacement therapy (ERT) with partially purified plasma enzyme was attempted but with little clinical improvement. Attaining clinical effectiveness with ERT for hypophosphatasia may require delivering functional TNSALP enzyme to bone. We tagged the C-terminal-anchorless TNSALP enzyme with an acidic oligopeptide (a six or eight residue stretch of L-Asp), and compared the biochemical properties of the purified tagged and untagged enzymes derived from Chinese hamster ovary cell lines. The specific activities of the purified enzymes tagged with the acidic oligopeptide were the same as the untagged enzyme. In vitro affinity experiments showed the tagged enzymes had 30-fold higher affinity for hydroxyapatite than the untagged enzyme. Lectin affinity chromatography for carbohydrate structure showed little difference among the three enzymes. Biodistribution pattern from single infusion of the fluorescence-labeled enzymes into mice showed delayed clearance from the plasma up to 18 h post infusion and the amount of tagged enzyme retained in bone was 4-fold greater than that of the untagged enzyme. In vitro mineralization assays with the bone marrow from a hypophosphatasia patient using each of the three enzymes in the presence of high concentrations of pyrophosphate provided evidence of bone mineralization. These results show the anchorless enzymes tagged with an acidic oligopeptide are delivered efficiently to bone and function bioactively in bone mineralization, at least in vitro. They suggest potential advantages for use of these tagged enzymes in ERT for hypophosphatasia, which should be explored.  相似文献   
29.
A survey conducted by cardiologists in Mozambique provided an opportunity for assessing the prevalence of congenital heart disease in public school children in Maputo. After randomization, a total of 2170 children were examined. Five children had clinical and echographic evidence of congenital heart disease, corresponding to a prevalence of 2.3 in 1000 (95% confidence interval: 1.0 to 5.4), 80% newly discovered during the survey. These findings confirm that congenital heart disease is at least as common in this South African black community as in Caucasians. Early detection of these cardiac diseases in children is important in order to prevent serious complications and to institute endocarditis prevention.  相似文献   
30.

Objectives

To examine the nature of the symptom cluster of emotional distress, fatigue, and cognitive difficulties in young and older breast cancer survivors (BCS); To assess the mediating role of subjective stress and coping strategies (emotional control and meaning-focused coping) in the association between age and symptom cluster.

Materials and Methods

Participants were 170 BCS, stages I-III, 1–12?months post-chemotherapy, filled-out the Fatigue, Emotional Control, Meaning—focused Coping, Emotional Distress and the Cognitive Difficulties Questionnaires. Statistical analyses included tests for difference between-groups Pearson correlations and Structural Equation Modeling for the assessment of the study model.

Results

Older BCS (aged 60–82) reported lower levels of emotional distress (M?=?0.87, SD?=?0.87), fatigue (M?=?3.85, SD?=?2.38), and cognitive difficulties (M?=?1.17, SD?=?1.07) compared to the younger BCS (aged 24–59) (emotional distress M?=?1.17, SD?=?0.85, fatigue M?=?5.02, SD?=?2.32, and cognitive difficulties M?=?1.66, SD?=?1.23, p?<?.01–,05). The older survivors reported lower levels of subjective stress and used more emotional control strategies compared to the younger BCS. The empirical model had good fit indices (χ2?=?27.60, p?=?0.20, χ2/df?=?1.26; CFI?=?0.98; TLI?=?0.98; NFI?=?0.95; RMSEA?=?0.04 (90% CI?=?0.00, 10) and showed that subjective stress, but not coping strategies, mediated the effect of age on symptom cluster severity.

Conclusions

Lower levels of subjective stress, but not coping strategies, mediated the association of age with the symptom cluster of emotional distress, fatigue and cognitive difficulties. Further research is needed to explore differences in subjective stress by age.  相似文献   
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