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Risk factors for extrahepatic biliary tract carcinoma in men: medical conditions and lifestyle: results from a European multicentre case-control study

OBJECTIVES: To identify risk factors of carcinoma of the extrahepatic biliary tract in men. METHODS: Newly diagnosed and histologically confirmed patients, 35-70 years old, were interviewed between 1995 and 1997 in Denmark, Sweden, France, Germany and Italy. Population controls were frequency-matched by age and region. Adjusted odds ratios and 95%-confidence intervals were estimated by logistic re

Genetic diversity and phenotypic variation in marginal populations of the locally endangered species Hordeum secanlinum (Poaceae).

Electrophoresis was used to compare variation in hordein polypeptide patterns and isozymes in five marginal populations ofHordeum secalinum (four Swedish and one Danish population) and four populations along the Atlantic coast from Denmark to Spain. Hordein patterns were uniform within and among Swedish and Danish populations whereas the materials from France and Spain were divergent. The banding

A comparison of two feedforward control structure assessment methods

The most common loop in an industrial plant is a SISO-loop with a PI(D)controller. If the loop is affected by disturbances,these can be handled by adding a feedforward control action. In an industrial control system there are many measured signals, apart from those of the loop, available. The question we address in this article is how to select the feedforward variable out of the available measure

Effects of enrichment on simple aquatic food webs

Simple models, based on Lotka-Volterra types of interactions between predator and prey, predict that enrichment will have a destabilizing effect on populations and that equilibrium population densities will change at the top trophic level and every second level below. We experimentally tested these predictions in three aquatic food web configurations subjected to either high or low nutrient additi

Bioavailability and sources of DOC and DON in macrophyte stands of a tropical coastal lake

Dissolved organic carbon (DOC) and nitrogen (DON) derived from aquatic and terrestrial vascular plants provide a major energy and nutrient source for freshwater and coastal marine biota. The bioavailability of this material may to a large extent depend on plant species. In this study, we have compared the bioavailability of DOC and DON sampled in two distinct stands of Typha domingensis and Eleoch

Monte Carlo simulations of polyelectrolytes inside viral capsids

Structural features of polyelectrolytes as single-stranded RNA or double-stranded DNA confined inside viral capsids and the thermodynamics of the encapsidation of the polyelectrolyte into the viral capsid have been examined for various polyelectrolyte lengths by using a coarse-grained model solved by Monte Carlo simulations. The capsid was modeled as a spherical shell with embedded charges and the

Concentrations of 60 elements in the soil solution as related to the soil acidity

Little is known about solubility and soil solution concentrations of most elements occurring in the solid phase of soils. This study reports changes in solution concentrations of 60 mineral elements following CaCO3 addition to a moderately acid semi-natural soil, and possible mechanisms accounting for the differing solubility patterns as related to soil acidity are discussed. Soil solutions were o

The nutritional quality of an infant food from quinoa and its effect on the plasma level of insulin-like growth factor-1 (IGF-1) in undernourished children.

An infant food product was manufactured by drum drying a pre-cooked slurry of quinoa (Chenopodium quinoa, Willd) flour. The chemical composition shows that the product is a potential source of valuable nutrients, like protein (16%), vitamin E (19 mg/kg), thiamine (0.7 mg/100 g), iron (70 mg/kg), zinc (48 mg/kg) and magnesium (1.8 g/kg), all the values expressed on dry basis, to pre-school children

WrbA bridges bacterial flavodoxins and eukaryotic NAD(P)H: quinone oxidoreductases

The crystal structure of the flavodoxin-like protein WrbA with oxidized FMN bound reveals a close relationship to mammalian NAD(P) H:quinone oxidoreductase, Nqo1. Structural comparison of WrbA, flavodoxin, and Nqo1 indicates how the twisted open-sheet fold of flavodoxins is elaborated to form multimers that extend catalytic function from one-electron transfer between protein partners using FMN to

Synthesis and transfection efficiencies of new lipophilic polyamines

A homologous series of lipophilic polyamines was synthesized and evaluated for DNA delivery and transfection efficiency. The series contained 1,4-butanediamine, 1,8-octanediamine, 2-[2-(2-amino-ethoxy)-ethoxy]-ethylamine, homospermidine, and homospermine covalently attached via their N-1 terminus to a 3,4-bis(oleyloxy)-benzyl motif. In addition, homospermidine and homospermine were also attached v

Decoherence and current fluctuations in tunneling through coupled quantum dots

The electronic transport through two coupled quantum dots in series can be described either in a fully coherent approach (e.g. density matrix description or nonequilibrium Green's functions) or in a simple sequential tunneling treatment (Pauli master equation with Fermi's Golden rule for coupling between the quantum dots). It turns out that both descriptions provide the same average current for no

Dispersion of atrial repolarization in patients with paroxysmal atrial fibrillation

To study the role of the dispersion of atrial repolarization (DAR) in the genesis of atrial fibrillation (AF), monophasic action potentials (MAP) were recorded simultaneously from a catheter at the high lateral right atrium (HLRA) and a catheter moving around the high, middle and low lateral right atrium (RA) the high, anterior and posterior septal RA and the RA appendage in 15 patients with parox

Redox signalling in chloroplasts and mitochondria: genomic and biochemical evidence for two-component regulatory systems in bioenergetic organelles

Redox chemistry is central to the primary functions of chloroplasts and mitochondria, that is, to energy conversion in photosynthesis and respiration. However, these bioenergetic organelles always contain very small, specialized genetic systems, relics of their bacterial origin. At huge cost, organellar genomes contain, typically, a mere 0.1% of the genetic information in a eukaryotic cell. There

Challenges Associated with Scaling up Artemisinin Combination Therapy in Sub-Saharan Africa A Review Article

Malaria is the leading cause of morbidity and mortality in Sub-Saharan Africa. One key strategic intervention is provision of early diagnosis and prompt effective treatment. A major setback has been the development of drug resistance to commonly used antimalarials. To overcome this, most countries in Sub-Saharan Africa have adopted Artemisinin Combination Therapy (ACT) as a first line treatment fo

A functional polymorphism in the SULT1A1 gene (G638A) is associated with risk of lung cancer in relation to tobacco smoking

Sulfotransferase 1A1, an important member of sulfotransferase superfamily, is involved in the biotransformation of many compounds including tobacco carcinogens. A single nucleotide polymorphism (G638A) in the sulfotransferase 1A1 (SULT1A1) gene causes Arg213His amino acid change and consequently results in significantly reduced enzyme activity and thermostability. We thus hypothesized that the var