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At least 217 records · Page 12Linked to original sources
PubMedDate not supplied

[Thrombosis of legs arteries: imputability of anti-phosphatidylethanolamine antibodies?].

BACKGROUND: At the beginning the antiphospholipid antibodies syndrome was associated with systemic lupus erythematosus. But since 1988 it has become a sole entity. Its current definition is based on the criteria established in 1999 by Sapporo and consists of associating the clinical criteria of thrombosis of arteries or peripheral veins and of miscarriage of pregnancy with the biological criteria. Either anti-cardiolipin antibodies or lupus anticoagulant must be present. Anti-phosphatidylethanolamine antibodies are not included in the Sapporo criteria. CASE REPORT: A non smoking, 43 year-old man showed a clinical manifestation of livedo on the thighs, and left knee and foot, associated with a rapidly extending cutaneous necrosis on the left toes. One year earlier his right leg was amputated up to half of the calf following distal gangrene. The gangrene was consecutive to a stent implantation after a significant stenosis of the right superficial femoral artery. The etiological investigations revealed neither thrombophily nor cholesterol embolism nor vasculitis. No sign of underlying neoplasia could be found. These clinical symptoms as well as the anamnesis were strongly suggestive of an antiphospholipid antibodies syndrome. The immunological dosages revealed isolated positive anti-phosphatidylethanolamine antibodies, persistent six weeks later. DISCUSSION: Several cases of clinical manifestations of the antiphospholipid antibodies syndrome have been described, without any anti-cardiolipin antibodies or lupus anticoagulant, but with presence of anti-phosphatidylethanolamine antibodies. In cases of these strong evocative symptoms but no evidence of the classical biological Sapporo criteria, these antibodies should be systematically searched for.

Adult↗
PubMed2005

Accounting for decay of linkage disequilibrium in haplotype inference and missing-data imputation.

Although many algorithms exist for estimating haplotypes from genotype data, none of them take full account of both the decay of linkage disequilibrium (LD) with distance and the order and spacing of genotyped markers. Here, we describe an algorithm that does take these factors into account, using a flexible model for the decay of LD with distance that can handle both "blocklike" and "nonblocklike" patterns of LD. We compare the accuracy of this approach with a range of other available algorithms in three ways: for reconstruction of randomly paired, molecularly determined male X chromosome haplotypes; for reconstruction of haplotypes obtained from trios in an autosomal region; and for estimation of missing genotypes in 50 autosomal genes that have been completely resequenced in 24 African Americans and 23 individuals of European descent. For the autosomal data sets, our new approach clearly outperforms the best available methods, whereas its accuracy in inferring the X chromosome haplotypes is only slightly superior. For estimation of missing genotypes, our method performed slightly better when the two subsamples were combined than when they were analyzed separately, which illustrates its robustness to population stratification. Our method is implemented in the software package PHASE (v2.1.1), available from the Stephens Lab Web site.

Algorithms↗
PubMed1976

Is Hodgkin's disease infectious? Discussion of an epidemiologic method used to impute that it is.

A method proposed by MacMahon for the differentiation between familial and environmental causes for disease has recently been applied to demonstrate an environmental etiology for Hodgkin's disease. It is shown that the method, which depends on the comparison of time-of-onset differences with age-at-onset differences for familial pairs with disease, is biased toward results suggestive of an environmental etiology when applied to data of the kind typically analyzed--data restricted to instances in which both members of a familial pair develop disease in a specified, limited time interval. Other features of such data are discussed.

Age Factors↗
PubMed2004

Imputing missing data.

Explore the source record for details and available documents.

Data Interpretation, Statistical↗
PubMed2003

Genome sharing in large pedigrees: multiple imputation of ibd for linkage detection.

Our objective is the development of robust methods for assessment of evidence for linkage of loci affecting a complex trait to a marker linkage group, using data on extended pedigrees. Using Markov chain Monte Carlo (MCMC) methods, it is possible to sample realizations from the distribution of gene identity by descent (IBD) patterns on a pedigree, conditional on observed data YM at multiple marker loci. Measures of gene IBDW which capture joint genome sharing in extended pedigrees often have unknown and highly skewed distributions, particularly when conditioned on marker data. MCMC provides a direct estimate of the distribution of such measures. Let W be the IBD measure from data YM, and W* the IBD measure from pseudo-data Y*M simulated with the same data availability and genetic marker model as the true data YM, but in the absence of linkage. Then measures of the difference in distributions of W and W* provide evidence for linkage. This approach extracts more information from the data YM than either comparison to the pedigree prior distribution of W or use of statistics that are expectations of W given the data YM. A small example is presented.

Chromosome Mapping↗
PubMed2000

[Imputable cutaneous eruption caused by ticlopidine after implantation of a coronary endoprosthesis: why not continue treatment?].

BACKGROUND: The decision to interrupt a ticlopidine regimen in a patient who develops an adverse effect can be particularly difficult when discontinuing the drug could lead to a high risk situation. CASE REPORT: A 64-year old patient developed a skin rash after taking ticlopidine for coronary artery stenting. Stopping ticlopidine could have led to stent occlusion and no alternative therapy seemed to be suitable. We therefore decided to carry on the treatment under close clinical surveillance. The skin signs rapidly resolved. DISCUSSION: This cases shows that ticlopidine may be continued in patients who develop an adverse skin reaction. The rapid involution of the cutaneous signs in our patient demonstrated that the risk of discontinuing treatment can be greater than that of continuing.

Angioplasty, Balloon, Coronary↗
PubMedDate not supplied

[Model of the impulse activity of a neuron receiving a stationary impulse imput].

The stationary model of spike activity of a single neuron is considered. This model exponential decay and constant threshold can be described as discontinuous one. The problem of calculation of Laplas' transform the probability density function (PDF) of interspike interval (ISI) can be reduced to the boundary problem for the usual differential equation. For the exponential PDF of the magnitude of the PSP the Laplas' transform of ISI PDF is expressed by special functions. The mean and standard deviation of ISI for different combinations of parameters were plotted with the aid of computer. The experiment without intracellular recoding, allowing to estimate the values of certain physiological parameters of a neuron on the basis of the model is proposed.

Models, Neurological↗
PubMed1993

Hierarchical logistic regression models for imputation of unresolved enumeration status in undercount estimation.

"In this article we describe a logistic regression modeling approach for nonresponse in the [U.S.] Post-Enumeration Survey (PES) that has desirable theoretical properties and that has performed well in practice.... In the 1990 PES, interviews were not obtained from approximately 1.2% of households in the sample, and approximately 2.1% of the individuals in interviewed households were considered unresolved after follow-up....The missing binary enumeration statuses for these unresolved cases were replaced with probabilities estimated under a statistical model that incorporated covariate information observed for these cases. This article describes an approach to modeling missing binary outcomes when there are a large number of covariates."

Americas↗