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The role of the radiologist in coronary angiography   总被引:1,自引:0,他引:1  
Levin  DC; Adams  DF; Abrams  HL 《Radiology》1977,125(2):313
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We analyzed the prevalence of α-thalassemia mutations in 298 subjects from Eastern Sicily (Italy) with reduced mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH), normal HbA2 and HbF, and normal serum iron. In 131 subjects (43.9%) we found six different genotypes of α-thalassemia: -α3.7/αα (36.6%), -α3.7/-α3.7 (27.5%), –MED/αα (10.0%), -α20.5/αα (9.1%), αHphIα/αα (8.4%), αHphIα/αHphIα (6.1%), and -α3.7HphIα (2.3%). Our data underline that in Eastern Sicily populations, the molecular screening of α-thalassemia mutations and/or deletions may be useful to better characterize the clinically asymptomatic subjects with a slightly reduced MCV and MCH and normal iron status.  相似文献   
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A patient with hypertrophic cardiomyopathy (HCM) and transfusion-dependent sideroblastic anemia, who presented with decompensated heart failure, is described. The present case demonstrates the usefulness of cardiac magnetic resonance imaging as a noninvasive imaging modality to assess the etiology of new systolic dysfunction in the setting of HCM. Cardiac magnetic resonance imaging is able to differentiate between the dilated ‘burned-out’ phase of HCM and a concomitant dilated cardiomyopathy secondary to myocarditis or hemosiderosis.  相似文献   
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In 2000, Teebi reported on a 4-year-old boy with a distinctive pattern of malformation, which he termed the "Nablus mask-like facial syndrome" (OMIM# 608156). Characterization of this syndrome has been difficult because of the paucity of patients described in the medical literature and its unknown etiology and pathogenesis. We present two patients with Nablus mask-like facial syndrome who both display a microdeletion in the 8q21-8q22 region detected by array-based comparative genomic hybridization. Patient 1, a boy, has a distinct facial appearance characterized by severe blepharophimosis, tight-appearing glistening facial skin, sparse and unruly hair, a flat and broad nose, and distinctive ears that are triangular in shape with prominent antihelices. He also demonstrates camptodactyly, contractures, unusual dentition, cryptorchidism, mild developmental delay, and a happy demeanor. Patient 2, a girl with a strikingly similar phenotype, was previously described in a report by Salpietro et al. 2003. She has distinctive ears, dental anomalies, and developmental delay. The etiology of her pattern of malformation was not identified at that time. Although high-resolution chromosome and subtelomeric FISH analyses were normal, array-based comparative genomic hybridization revealed an approximately 4 Mb deletion involving the 8q21.3-8q22.1 region in both patients. This region encompasses a number of genes that may contribute to this unique phenotype. These results demonstrate a chromosomal microdeletion as the etiology of Nablus mask-like facial syndrome and emphasize the diagnostic utility of array-based comparative genomic hybridization in the evaluation of multiple malformation syndromes of previously unrecognized causation.  相似文献   
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Objective

Participants in clinical trials of spinal manipulation have not been rigorously blinded to group assignment. This study reports on secondary analyses of the retention of participant blinding beyond the immediate posttreatment time frame following a single-session, randomized clinical study. A novel control cervical manipulation procedure that has previously been shown to be therapeutically inert was contrasted with a typical manipulation procedure.

Methods

A randomized clinical study of a single session of typical vs sham-control manipulation in patients with chronic neck pain was conducted. Findings of self-reported group registration at 24 to 48 hours posttreatment were computed. The Blinding Index (BI) of Bang et al was then applied to both the immediate and post–24- to 48-hour results.

Results

Twenty-four to 48 hours after treatment, 94% and 22% of participants in the typical and control groups, respectively, correctly identified their group assignment. When analyzed with the BI of Bang et al, the immediate posttreatment BI for the group receiving a typical manipulation was 0.22 (95% confidence interval [CI], − 0.03 to 0.47); for the group receiving a control manipulation, it was 0.19 (95% CI, − 0.06 to 0.43). The BI at post-24 hours was as follows: typical = 0.75 (95% CI, 0.59-0.91) and control = − 0.34 (95% CI, − 0.58 to − 0.11).

Conclusions

This study found that the novel sham-control cervical manipulation procedure may be effective in blinding sham group allocation up to 48 hours posttreatment. It appears that, at 48 hours posttreatment, the modified form of the typical cervical manipulation was not. The sham-control procedure appears to be a promising procedure for future clinical trials.  相似文献   
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