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排序方式: 共有940条查询结果,搜索用时 31 毫秒
101.
102.
Nora Pashayan Paul DP Pharoah Johanna Schleutker Kirsi Talala Teuvo LJ Tammela Liisa M??tt?nen Patricia Harrington Jonathan Tyrer Rosalind Eeles Stephen W Duffy Anssi Auvinen 《British journal of cancer》2015,113(7):1086-1093
Background:
We derived estimates of overdiagnosis by polygenic risk groups and examined whether polygenic risk-stratified screening for prostate cancer reduces overdiagnosis.Methods:
We calculated the polygenic risk score based on genotypes of 66 known prostate cancer loci for 4967 men from the Finnish section of the European Randomised Study of Screening for Prostate Cancer. We stratified the 72 072 men in the trial into those with polygenic risk below and above the median. Using a maximum likelihood method based on interval cancers, we estimated the mean sojourn time (MST) and episode sensitivity. For each polygenic risk group, we estimated the proportion of screen-detected cancers that are likely to be overdiagnosed from the difference between the observed and expected number of screen-detected cancers.Results:
Of the prostate cancers, 74% occurred among men with polygenic risk above population median. The sensitivity was 0.55 (95% confidence interval (CI) 0.45–0.65) and MST 6.3 (95% CI 4.2–8.3) years. The overall overdiagnosis was 42% (95% CI 37–52) of the screen-detected cancers, with 58% (95% CI 54–65) in men with the lower and 37% (95% CI 31–47) in those with higher polygenic risk.Conclusion:
Targeting screening to men at higher polygenic risk could reduce the proportion of cancers overdiagnosed. 相似文献103.
104.
Differential synthesis of spore coat proteins in prespore and prestalk cells of Dictyostelium. 总被引:11,自引:1,他引:11
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K M Devine J H Morrissey W F Loomis 《Proceedings of the National Academy of Sciences of the United States of America》1982,79(23):7361-7365
The major spore coat proteins (SP60, SP70, and SP96) of Dictyostelium discoideum have been analyzed by using two-dimensional nonequilibrium pH gradient electrophoresis. These proteins have been characterized with respect to electrophoretic behavior, metachromatic staining with silver, and posttranslational modifications; these techniques allow unambiguous identification of these proteins in silver-stained gels and autofluorograms of total cell extracts. They are synthesized by cells in the prespore region of migrating slugs, ultimately becoming major components of mature spores, but are not detectable either in cells in the prestalk region of slugs or in mature stalk cells. The ease with which these relatively abundant proteins can be recognized on two-dimensional gels makes them very useful markers for spatial and temporal differentiation in this organism. 相似文献
105.
Preparation of factor IX deficient human plasma by immunoaffinity chromatography using a monoclonal antibody 总被引:1,自引:0,他引:1
Goodall AH; Kemble G; O'Brien DP; Rawlings E; Rotblat F; Russell GC; Janossy G; Tuddenham EG 《Blood》1982,59(3):664-670
A murine hybridoma clone is described that grows continuously in culture and produces a monoclonal antibody we have called Royal Free Monoclonal Antibody to factor IX No. 1 (RFF-IX/1). This has high affinity for a coagulation site on factor IX. RFF-IX/1 immobilised on sepharose can be used to deplete factor IX from normal human plasma. This immunoaffinity depleted plasma is indistinguishable from severe Christmas disease plasma and can be used as the substrate in a one stage coagulation assay for factor IX. The affinity column has high capacity and can be regenerated so that large scale production from normal plasma of factor IX deficient plasma as a diagnostic reagent is now feasible. 相似文献
106.
Alterations in neutrophil subpopulations during human hemodialysis or following injection of C5a des arg into rabbits were studied. Whereas baseline peripheral blood neutrophils contained approximately 80% of cells that formed rosettes with IgG-sensitized erythrocytes, neutrophils harvested at the granulocyte nadir (20 min after initiating hemodialysis or the injection of C5a des arg) were markedly depleted of this population. This was seen in a change in ratio of rosette-forming neutrophils (RFN) to non-rosette-forming neutrophils (non-RFN) from 4:1 at 0 time to 1:2 at 20 min. Since non-RFN are less active in assays of adherence and chemotaxis, these alterations in circulating neutrophil populations were reflected in abnormal functional capacity of neutrophils harvested at 20 min. To study the mechanism of RFN depletion, we investigated the ability of C5a des arg to aggregate various human neutrophil suspensions. Unfractionated neutrophils and RFN demonstrated prompt in vitro aggregation in response to C5a des arg, whereas this activated complement fragment induced little aggregation in a population enriched for non-RFN. These results may explain the alterations in neutrophil adherence, chemotaxis, phagocytosis, and bactericidal activity, which have been reported to accompany clinical disorders characterized by in vivo complement activation (i.e., hemodialysis or gram-negative sepsis). 相似文献
107.
CH Reynolds BBSc DP Crewther PhD SG Crewther PhD SJ West BSc 《Clinical & experimental ophthalmology》1998,26(S1):S117-S119
108.
109.
110.
A PIL for every ill? Patient information leaflets (PILs): a review of past, present and future use 总被引:9,自引:0,他引:9
Kenny T; Wilson RG; Purves IN; Clark J Sr; Newton LD; Newton DP; Moseley DV 《Family practice》1998,15(5):471-479
This article reviews the usefulness and importance of written information,
specifically leaflets, being given to patients. Evidence suggesting how
both patient and doctor may benefit from the giving of written information
is reviewed. Identification of good practice relating to the content and
readability of leaflets is discussed. An argument is put forward that the
giving of written information is an under-utilized resource in contributing
to improving patient outcomes but that this may be changing with the
increasing use of patient leaflet databases. The advantages and
disadvantages of computer- generated patient leaflets are discussed and
desirable further areas of research on computer-generated leaflets are
proposed.
相似文献