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Properties of a filamentous virus of the honey bee (Apis mellifera)   总被引:2,自引:0,他引:2  
An ellipsoidal particle, measuring 450 x 150 nm, from honey bees comprises a nucleocapsid measuring 3000 x 40 nm, containing double-stranded DNA with a molecular weight of approximately 12 x 10(6), which is coiled within a membrane. The buoyant densities in CsCl of the whole particle, nucleocapsid, DNA and DNA with ethidium bromide are 1.28, 1.36, 1.71 and 1.61 g/ml, respectively. The particle contains about 12 proteins, with molecular weights ranging from 13,000 to 70,000, which are distributed approximately equally between the membrane and the nucleocapsid.  相似文献   
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Determined the efficacy of profile analysis with a prison population (63 white, 63 black) of the Petersburg Federal Correctional Institution as Ss. By use of Veldman's Hierarchical Profile Analysis, five distinctive WAIS profile types were derived empirically for each racial group. Analyses of covariance that controlled for full-scale IQ differences revealed significant differences among the profile types within each race in terms of Stanford Achievement Test scores and MMPI T-scores. Further, partial correlations indepepdent of full-scale IQ revealed significant relationships between some of the profile types and the commission of rule infractions while incarcerated. These findings are interpreted as supportive of profile analysis with inmate populations. However, it is suggested that further research be effected to cross-validate these findings.  相似文献   
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Twelve IUDs that had been worn from 8 years 10 months to 24 years were examined by SEM. Photomicrographs of selected samples are shown, and a discussion of the nature of the surface encrustations is provided. The authors are of the opinion that surface encrustations are generic to different types of IUDs and that their clinical significance is presently unknown.
Resumen Doce DIU que fueron usados de 8 años 10 meses a 24 años, se examinaron por microscopio de barrido. Se muestran microfotografías de especímenes seleccionados y se especula sobre la naturaleza de las incrustaciones en la superficie. Los autores son de opinión que las incrustaciones en la superficie son comunes para los distintos tipos de DIU y que actualmente se desconoce su significado clínico.

Résumé Douze stérilets qui ont été utilisés pendant une période allant de 8 ans et 10 mois à 24 ans ont fait object 'dun examen sous microscope électronique. Des microphotographies de spécimens sélectionnés illustrent ce document. Après avoir examiné la nature des incrustations superficielles, les auterus en ont tiré la conclusion que les différents types de stérilets présentent tous les mêmes incrustations dont on ne connaît pas encore la signification clinique.


Presented at the 3rd International Meeting of the Society for the Advancement of Contraception, Bordeaux, France, September, 1985  相似文献   
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BackgroundCystic Fibrosis (CF) is a multi-systemic disorder resulting from genetic variation in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene which can result in bronchiectasis, chronic sinusitis, pancreatic malabsorption, cholestatic liver disease and distal intestinal obstructive syndrome. This study generates multi-dimensional clinical phenotypes that capture the complexity and spectrum of the disease manifestations seen in adult CF patients using statistically robust techniques.MethodsPre-transplant clinical data from adult (age ≥18 years) CF patients (n = 992) seen in six regionally distinct US CF centers between 1/1/2014 and 6/30/2015 were included. Demographic, spirometry, nutritional, microbiological and therapy data were used to generate clusters using the Random Forests statistical-learning and Partitioning around Medoids (PAM) clustering algorithms. Five commonly measured demographic, physiological and nutritional parameters were needed to create the final phenotypes that are highly similar to a regionally matched group of patients from the CF Foundation Patient RegistryResultsThis approach identified high-risk phenotypes with expected characteristics including high rates of pancreatic insufficiency, diabetes and Pseudomonas aeruginosa colonization. It also identified unexpected populations including a) a male-dominated, well-nourished group with good lung function with a high prevalence of severe genotypes (i.e. 60% subjects had two minimal function CFTR variations), b) and an older, “survivor” phenotype that had high rates of chronic P. aeruginosa infection.ConclusionsThis study identified recognizable phenotypes that capture the clinical complexity in a statistically robust manner and which may aide in the identification of specific genetic and environmental factors responsible for these disease manifestation patterns.  相似文献   
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Total-body positron emission tomography (PET) is a useful diagnostic tool for evaluating malignant disease. However, tumour detection is limited by image artefacts due to the lack of attenuation correction and noise. Attenuation correction may be possible using transmission data acquired after or simultaneously with emission data. Despite the elimination of attenuation artefacts, however, tumour detection is still hampered by noise, which is amplified during image reconstruction by filtered backprojection (FBP). We have investigated, as an alternative to FBP, an accelerated expectation maximization (EM) algorithm for its potential to improve tumour detectability in total-body PET. Signal to noise ratio (SNR), calculated for a tumour with respect to the surrounding background, is used as a figure of merit. A software tumour phantom, with conditions typical of those encountered in a total-body PET study using simultaneous acquisition, is used to optimize and compare various reconstruction approaches. Accelerated EM reconstruction followed by two-dimensional filtering is shown to yield significantly higher SNR than FBP for a range of tumour sizes, concentrations and counting statistics (deltaSNR = 6.3 +/- 3.9, p < 0.001). The methods developed are illustrated by examples derived from physical phantom and patient data.  相似文献   
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