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1.
Two fast magnetic resonance (MR) imaging techniques, advanced Fourier and partial-flip imaging, were used at 0.35 T to examine 21 patients with suspected intracranial lesions; the results were quantitatively compared with a conventional spin-echo study. Both of the fast MR techniques yielded a fourfold reduction in imaging time per section. The advanced Fourier sequence showed contrast that was identical to the conventional spin-echo study with signal-to-noise ratios of 58% and 57% for the first and second echoes, respectively. The partial-flip sequence showed a contrast of 109% and 57% for lesions versus substantia alba, and 107% and 78% for substantia grisea versus substantia alba relative to the first and second echoes of the conventional spin-echo study. The partial-flip sequence was particularly sensitive to magnetic susceptibility; this produced artifacts that may undermine the usefulness of partial flip for routine screening in certain parts of the brain. However, this susceptibility significantly improved the detection of intracranial hemorrhage when compared with the spin-echo sequence, particularly when combined with phase mapping of the partial-flip study. 相似文献
2.
Missense mutation in a von Willebrand factor type A domain of the alpha 3(VI) collagen gene (COL6A3) in a family with Bethlem myopathy 总被引:2,自引:0,他引:2
Pan TC; Zhang RZ; Pericak-Vance MA; Tandan R; Fries T; Stajich JM; Viles K; Vance JM; Chu ML; Speer MC 《Human molecular genetics》1998,7(5):807-812
The Bethlem myopathy is a rare autosomal dominant proximal myopathy
characterized by early childhood onset and joint contractures. Evidence for
linkage and genetic heterogeneity has been established, with the majority
of families linked to 21q22.3 and one large family linked to 2q37,
implicating the three type VI collagen subunit genes, COL6A1 (chromosome
21), COL6A2 (chromosome 21) and COL6A3 (chromosome 2) as candidate genes.
Mutations of the invariant glycine residues in the triple-helical
domain-coding region of COL6A1 and COL6A2 have been reported previously in
the chromosome 21-linked families. We report here the identification of a
G-->A mutation in the N-terminal globular domain-coding region of COL6A3
in a large American pedigree (19 affected, 12 unaffected), leading to the
substitution of glycine by glutamic acid in the N2 motif, which is
homologous to the type A domains of the von Willebrand factor. This
mutation segregated to all affected family members, to no unaffected family
members, and was not identified in 338 unrelated Caucasian control
chromosomes. Thus mutations in either the triple-helical domain or the
globular domain of type VI collagen appear to cause Bethlem myopathy.
相似文献
3.
PURPOSE: Since 1998, prestorage leucoreduction of cellular blood components (BC) is mandatory in France. The French Blood Service needs to follow the data on the quality of the BC prepared by blood centers. This article gives an overview of the quality control (QC) data from 2001 to 2006. MATERIAL AND METHODS: QC data are submitted to a central data bank by each centre. The data are stratified according to preparation process for analysis of key performance criteria - residual leukocytes and haemoglobin or platelet content. BC preparation processes, methods for measuring haemoglobin and platelet content, and for counting residual leukocytes are those routinely employed by centers. RESULTS: The preparation process of red cell concentrates (RCC) influences the haemoglobin content: 57.6+/-6.8 g per unit versus 50.9+/-5.4 g per unit for whole blood or RCC filtration, respectively. Apheresis RCC exhibits a reduced variability (51.2+/-3.4 g per unit). For apheresis platelet concentrates, the median residual leukocyte count remains low for all separators (0.019-0.044 x 10(6)leukocytes per unit, in 2006). However, the percentage of units exceeding 1 x 10(6)leukocytes per unit is significantly higher with one separator (1.8% versus 0.8%, in 2006). For pooled buffy-coat derived platelets, we observed a significant increase in platelet recovery throughout the years (0.66-0.77 x 10(11)platelets per buffy-coat in 2001 and 2006, respectively). CONCLUSION: Our QC data show an overall compliance with the requirements for cellular BC. Our data bank is useful to inform on the performance of leucoreduced BC preparation processes carried out with market available devices. 相似文献
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CC Thorn M Smith O Aziz TC Holme 《Annals of the Royal College of Surgeons of England》2013,95(1):52-56
Introduction
Perioperative scoring systems aim to predict outcome following surgery and are used in preoperative counselling to guide management and to facilitate internal or external audit. The Waterlow score is used prospectively in many UK hospitals to stratify the risk of decubitus ulcer development. The primary aim of this study was to assess the potential value of this existing scoring system in the prediction of mortality and morbidity in a general surgical and vascular cohort.Methods
A total of 101 consecutive moderate to high risk emergency and elective surgical patients were identified through a single institution database. The preoperative Waterlow score and outcome data pertaining to that admission were collected. The discriminatory power of the Waterlow score was compared against that of the American Society of Anesthesiologists (ASA) grade and the Portsmouth Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity (P-POSSUM).Results
The inpatient mortality rate was 17% and the 30-day morbidity rate was 29%. A statistically significant association was demonstrated between the preoperative Waterlow score and inpatient mortality (p<0.0001) and 30-day morbidity (p=0.0002). Using a threshold Waterlow score of 20 to dichotomise risk, accuracies of 0.84 and 0.76 for prediction of mortality and morbidity were demonstrated. In comparison with P-POSSUM, the preoperative Waterlow score performed well on receiver operating characteristic analysis. With respect to mortality, the area under the curve was 0.81 (0.80–0.85) and for morbidity it was 0.72 (0.69–0.76). The ASA grade achieved a similar level of discrimination.Conclusions
The Waterlow score is collected routinely by nursing staff in many hospitals and might therefore be an attractive means of predicting postoperative morbidity and mortality. It might also function to stratify perioperative risk for comparison of surgical outcome data. A prospective study comparing these risk prediction scores is required to support these findings. 相似文献8.
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DK Bilku AR Dennison TC Hall MS Metcalfe G Garcea 《Annals of the Royal College of Surgeons of England》2014,96(1):15-22