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1.
Intraobserver and interobserver variation in the sonographic grading of placental maturity. 总被引:4,自引:0,他引:4
OBJECTIVES: The appearance of Grannum Grade III changes in the placenta at around 34-36 weeks is a predictor of adverse perinatal outcome, which may be reduced by reporting to the clinician. This has led to the suggestion that the placental grade should be noted during any third-trimester scan. There are no published data on the reproducibility of sonographic Grannum grading of the placenta; the objective of this study was to evaluate intra- and interobserver variation. METHODS: Fifty-five placental images from normal and complicated pregnancies of several different gestational ages were collected between April and October 2001. Three fetal medicine consultants and three experienced sonographers graded the images as 0, I, II, III or ungradeable. They then regraded the same images, presented in a different order and with different codes, 4-6 weeks later. Observers were blinded to their previous grading and to each others'. Weighted kappa (kappa), with linear weights, was used to look for strength of agreement. RESULTS: There was good agreement between the two observations of each placental image for five observers (kappa = 0.61 to 0.90), and moderate agreement for one observer (kappa = 0.56). However, the kappa-values for comparisons between the 15 pairs of observers ranged from 0.24 to 0.69 with six values below 0.41, indicating only fair agreement. This was confirmed by the overall kappa-value of 0.24 between all six observers. The agreement between the observers for Grade III placenta was poor, with an overall kappa-value of 0.09. CONCLUSIONS: Although intraobserver agreement was generally good, interobserver agreement was only fair for all grades and poor for Grade III placenta. This may be an indication that Grannum grading is not reproducible or it may reflect a need for training in those performing grading. Such variation may limit the effectiveness of reporting Grannum grades in clinical practice. 相似文献
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Codon usage studies have been carried out on the coding sequences of Thermoplasma acidophilum, which is an archaeon and grows at very low pH and high temperature. Overall codon usage data analysis indicates that all the four bases are almost equifrequent at the third position of codons, which is expected (since genomic GC % of this genome is about 46%). However, multivariate statistical analysis indicates that there are two major trends in the codon usage variation among the genes in this organism. In the first major trend it is observed that genes having G and C ending codons are clustered at one end while, A and T ending ones are clustered at the other end. We have also found a significant positive correlation between the expressivities of genes and GC contents at the synonymous third codon positions. In the second major trend, it is seen that the genes are clustered into three distinct parts. A comparative analyses of codon usage data of T. acidophilum and Sulfolobus solfataricus reveals that one of the three clusters of genes of T. acidophilum is very similar to a considerable number of S. solfataricus genes, suggesting possible occurrences of lateral gene transfer between these two microorganisms as reported by earlier workers. 相似文献
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Sau W Cheung Chad A Shaw Wei Yu Jiangzham Li Zhishuo Ou Ankita Patel Svetlana A Yatsenko Mitchell L Cooper Patti Furman Pawel Stankiewicz Pawal Stankiewicz James R Lupski A Craig Chinault Arthur L Beaudet 《Genetics in medicine》2005,7(6):422-432
PURPOSE: We developed a microarray for clinical diagnosis of chromosomal disorders using large insert genomic DNA clones as targets for comparative genomic hybridization (CGH). METHODS: The array contains 362 FISH-verified clones that span genomic regions implicated in over 40 known human genomic disorders and representative subtelomeric clones for each of the 41 clinically relevant human chromosome telomeres. Three or four clones from almost all deletion or duplication genomic regions and three or more clones for each subtelomeric region were included. We tested chromosome microarray analysis (CMA) in a masked fashion by examining genomic DNA from 25 patients who were previously ascertained in a genetic clinic and studied by conventional cytogenetics. A novel software package implemented in the R statistical programming language was developed for normalization, visualization, and inference. RESULTS: The CMA results were entirely consistent with previous cytogenetic and FISH findings. For clone by clone analysis, the sensitivity was estimated to be 96.7% and the specificity was 99.1%. Major advantages of this selected human genome array include the following: interrogation of clinically relevant genomic regions, the ability to test for a wide range of duplication and deletion syndromes in a single analysis, the ability to detect duplications that would likely be undetected by metaphase FISH, and ease of confirmation of suspected genomic changes by conventional FISH testing currently available in the cytogenetics laboratory. CONCLUSION: The array is an attractive alternative to telomere FISH and locus-specific FISH, but it does not include uniform coverage across the arms of each chromosome and is not intended to substitute for a standard karyotype. Limitations of CMA include the inability to detect both balanced chromosome changes and low levels of mosaicism. 相似文献
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The effect of age of a poly-acid-modified composite resin on repair bond strength after different methods of surface conditioning was studied. Surface conditioning methods included the following: maleic acid with resin application; polyacrylic acid with resin application; sand-blasting with resin application. Shear bond testing between the aged and new material was carried out with an Instron Universal Testing Machine. Although repair bonds strengths after all surface conditioning methods were significantly higher than the control group at 1 week, no statistically significant differences in bond strengths were noted after aging the material for 6 months. After all aging periods, surface conditioning with sand-blasting and resin application resulted in the highest repair bond for poly-acid-modified composite resins. Specimens with cohesive failure in the material gave significantly higher repair bond strengths than specimens with adhesive failure at the repaired interface. 相似文献
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A de novo 1.58 Mb deletion,including MAP2K6 and mapping 1.28 Mb upstream to SOX9, identified in a patient with Pierre Robin sequence and osteopenia with multiple fractures
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David Bin-Chia Wu Edwin Ho Ming Lee Wai Sau Chung Danielle Pui Yu Chow Vivian Wing Yan Lee Ming Cheuk Wong Kenneth Kwing Chin Lee 《Psychiatry research》2013
Schizophrenia is one of the most expensive psychiatric illnesses. This study compared retrospectively health-care resources consumed 12 months before and 24 months after risperidone long-acting injection (RLAI) treatment in Hong Kong. A mirror-image analysis was conducted using data (N=191) from three public hospitals in Hong Kong from 2003 to 2007. The main outcome measure was hospitalisation cost. Other secondary outcomes such as hospitalisation episodes, outpatient visits and adverse events were also compared. A predictive model was established using linear regression based on generalised estimating equations. Analysis showed that RLAI was associated with a reduction in hospitalisation cost by HK$10,001,390 (24.7%) (HK$40,418,694 vs. HK$30,417,303; P-value <0.05). Days of hospitalisation were reduced by 1538 days (10.1%) (15,271 vs. 13,733; P-value <0.05). The predictive model estimated that the hospitalisation cost of patients using RLAI was only 11.1% (3.1–3.93%, 95% confidence interval (CI)) compared to those receiving conventional antipsychotics combined with oral risperidone. Cost of hospitalisation was significantly reduced after RLAI therapy. However, results should be considered as indicative or suggestive only, due to potential channelling bias where certain drug regimens are preferentially prescribed to patients with particular conditions. The findings from our study may be useful in health-care decision making considering treatment options for schizophrenia in resource-limited settings. 相似文献