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61.
Diagnostic role of an immunoassay-detected polymorphism of factor IX for potential carriers of hemophilia B 总被引:3,自引:1,他引:3
In hemophilia B, assays based on a monoclonal antifactor IX specific for the Thr-148 variant of an exonic polymorphism have diagnosed carriers in selected families by either establishing linkage or by indicating the presence or absence of a given normal factor IX. The sensitivity of the immunoassays for detecting heterozygous women was explored by comparing results from immunoassays with solid-phase polyclonal v the monoclonal antifactor IXs. Factor IX with the normal Ala-148 variant gave a flat dilution curve, qualitatively distinct from factor IX with the Thr-148 variant in the monoclonal assay. The two were indistinguishable in the polyclonal assay. Mixtures of equal amounts of the two types gave an intermediate result, about half as reactive in the monoclonal as compared with the polyclonal assay system. Whereas mixtures with 10% Ala-148 and 90% Thr-148 factor IXs could not readily be distinguished from Thr-148 factor IX plasma, as little as 1% of the Thr-148 protein was detected in Ala-148 factor IX plasma. The frequency of the Ala-148 variant varied in individuals with different ethnic backgrounds; it was found in 29% of white, 12% of black, and none of Asian blood donors' factor IX genes in Seattle. Only 4% of samples from South African black men were nonreactive (ie, Ala- 148). The Thr/Ala-148 dimorphism is in strong linkage disequilibrium with Taql restriction fragment length polymorphisms (RFLPs). Three recombinations were noted in normal white genes and one in a normal black factor IX gene (less than 2% of those examined). In 34 white families with at least one woman being a possible carrier, genetically, the immunoassay results were informative in 18. RFLP analyses were informative in eight of the 15 families tested. In five families each, assignment of carrier status was made to a woman by only DNA or only immunoassay results, whereas the other approach was noninformative. The immunoassays provide a rapid, inexpensive screening test and complement DNA analysis in white women who are potential carriers of hemophilia B. 相似文献
62.
Priyanka Jha Liina Pder Charis Bourgioti Nishat Bharwani Sara Lewis Amita Kamath Stephanie Nougaret Philippe Soyer Michael Weston Rosa P. Castillo Aki Kido Rosemarie Forstner Gabriele Masselli 《European radiology》2020,30(5):2604-2615
This study was conducted in order to establish the joint Society of Abdominal Radiology (SAR) and European Society of Urogenital Radiology (ESUR) guidelines on placenta accreta spectrum (PAS) disorders and propose strategies to standardize image acquisition, interpretation, and reporting for this condition with MRI. The published evidence-based data and the opinion of experts were combined using the RAND–UCLA Appropriateness Method and formed the basis for these consensus guidelines. The responses of the experts to questions regarding the details of patient preparation, MRI protocol, image interpretation, and reporting were collected, analyzed, and classified as “recommended” versus “not recommended” (if at least 80% consensus among experts) or uncertain (if less than 80% consensus among experts). Consensus regarding image acquisition, interpretation, and reporting was determined using the RAND–UCLA Appropriateness Method. The use of a tailored MRI protocol and standardized report was recommended. A standardized imaging protocol and reporting system ensures recognition of the salient features of PAS disorders. These consensus recommendations should be used as a guide for the evaluation of PAS disorders with MRI.
• MRI is a powerful adjunct to ultrasound and provides valuable information on the topography and depth of placental invasion.
• Consensus statement proposed a common lexicon to allow for uniformity in MRI acquisition, interpretation, and reporting of PAS disorders.
• Seven MRI features, namely intraplacental dark T2 bands, uterine/placental bulge, loss of low T2 retroplacental line, myometrial thinning/disruption, bladder wall interruption, focal exophytic placental mass, and abnormal vasculature of the placental bed, reached consensus and are categorized as “recommended” for diagnosing PAS disorders. 相似文献
63.
Sinclair Jonathan Mann James Weston George Poulsen Nikolaj Edmundson Christopher James Bentley Ian Stone Mark 《Sport Sciences for Health》2020,16(2):227-237
Sport Sciences for Health - The aim of the current investigation was to comparatively examine the effects of knee wraps/sleeves on kinetics, three-dimensional kinematics and muscle forces during... 相似文献
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65.
Kenneth M. Yamada James A. Weston 《Proceedings of the National Academy of Sciences of the United States of America》1974,71(9):3492-3496
A cell surface component has been isolated in partially purified form from cultured chick embryo and chick heart fibroblasts. This glycoprotein is similar to a protein recently reported to be present at the surface of normal cells, and missing after neoplastic transformation. It is a major cell surface glycoprotein that is synthesized by cultured fibroblasts, but is not collagen. It is shown to be markedly trypsin-sensitive, and its recovery from the cell surface is dependent on cell density. It is excluded from Sephadex G-200, but is not rapidly sedimented by ultracentrifugation, and has an apparent molecular weight of 220,000. The isolation of this cell surface glycoprotein may now provide a means of determining its function. 相似文献
66.
Genome sequence determinations and analyses of novel circoviruses from goose and pigeon 总被引:12,自引:0,他引:12
The genomes of novel circoviruses from goose and pigeon, which were isolated using degenerate primer and inverse primer PCR methods, were cloned and sequenced. Comparative nucleotide (nt) sequence analyses showed that the goose circovirus (GCV) and pigeon circovirus (PiCV) possessed genomes which were 1821 and 2037 or 2036 nt, respectively, and which had features in common with the genomes of porcine circoviruses types 1 and 2 (PCV1, PCV2) and psittacine beak and feather disease virus (BFDV), such that they can now be assigned to the genus Circovirus of the family Circoviridae. Common features include the possession of (i) a potential stem-loop/nonanucleotide motif with which the initiation of rolling circle replication of the virus DNA is associated; (ii) two major ORFs, located on the virus (V1 ORF) and complementary (C1 ORF) strands, which encode the replication-associated protein (Rep) and capsid protein, respectively; (iii) high levels of amino acid identity (41.2--58.2%) shared with other circovirus Rep proteins; and (iv) direct/inverted repeat sequences within the putative intergenic region. On the basis of nt and amino acid sequence identities, GCV is substantially less closely related to BFDV than PiCV is to BFDV. 相似文献
67.
Zeynettin Akkus Jason Cai Arunnit Boonrod Atefeh Zeinoddini Alexander D. Weston Kenneth A. Philbrick Bradley J. Erickson 《Journal of the American College of Radiology》2019,16(9):1318-1328
Ultrasound is the most commonly used imaging modality in clinical practice because it is a nonionizing, low-cost, and portable point-of-care imaging tool that provides real-time images. Artificial intelligence (AI)–powered ultrasound is becoming more mature and getting closer to routine clinical applications in recent times because of an increased need for efficient and objective acquisition and evaluation of ultrasound images. Because ultrasound images involve operator-, patient-, and scanner-dependent variations, the adaptation of classical machine learning methods to clinical applications becomes challenging. With their self-learning ability, deep-learning (DL) methods are able to harness exponentially growing graphics processing unit computing power to identify abstract and complex imaging features. This has given rise to tremendous opportunities such as providing robust and generalizable AI models for improving image acquisition, real-time assessment of image quality, objective diagnosis and detection of diseases, and optimizing ultrasound clinical workflow. In this report, the authors review current DL approaches and research directions in rapidly advancing ultrasound technology and present their outlook on future directions and trends for DL techniques to further improve diagnosis, reduce health care cost, and optimize ultrasound clinical workflow. 相似文献
68.
Sarah Elison Samantha Weston Glyn Davies Stephanie Dugdale Jonathan Ward 《Drugs (Abingdon, England)》2016,23(2):176-185
Reshaping substance misuse treatment in prisons is central to the UK Government’s drive to address substance dependence in the prison population and reduce substance-related offending and recidivism. Therefore, a through-care project to support prisoners released from custody to community, “Gateways”, is taking place across North-West England. Amongst support with housing, education, training and employment, Gateways incorporates the Breaking Free Online (BFO) substance misuse treatment programme. Aims: To explore BFO’s potential to provide support to prisoners’ substance misuse recovery and continuity of care post-release, and examine quantitative outcomes provided by prisoners who have used the programme. Methods: Qualitative interviews with prisoners and analyses of quantitative psychometric data collected pre- and post-intervention. Findings: Themes emerging from qualitative data around prisoners’ experiences of engaging with BFO illustrate its potential for use in prison settings and also upon release to the community. Significant quantitative improvements to quality of life, severity of substance dependence and aspects of recovery progression illustrate initial effectiveness of BFO. Conclusions: The BFO programme demonstrates potential in providing effective treatment for offenders with substance misuse difficulties, and specifically in delivering continuity of care following release to the community. 相似文献
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