Search results

Filter

Filetype

Your search for "*" yielded 530849 hits

Exercise during growth and bone mineral density and fractures in old age

If exercise is to be recommended during growth, benefits in bone mineral density (BMD) must be maintained in old age and shown to prevent fractures. Our cross-sectional study of soccer players suggests that a high BMD is no longer recorded after retirement and fracture frequency is no less than predicted in old age.

Does Helicobacter pylori infection per se cause gastric cancer or duodenal ulcer? Inadequate evidence in Mongolian gerbils and inbred mice

A role for Helicobacter pylori infection in the development of gastric cancer in humans is well established; however, evidence for its carcinogenicity in animals remains inadequate. Mongolian gerbils and mice are commonly used to investigate the carcinogenicity of H. pylori, yet it is unclear whether H. pylori infection per se causes gastric cancer or duodenal ulcers in these animal models. Gastri

Sympathomimetic drug allergy: cross-reactivity study by patch test

INTRODUCTION: Sympathomimetic (alpha-adrenergic) drugs are mainly used because of their vasoconstrictor properties, for nasal congestion, or as mydriatics. Although sympathomimetic drugs are used often, allergic reactions are rare, especially when the drugs are administered systemically. Cross-reactivity may exist among catecholamine derivatives, although reported data on this are contradictory. I

A test for multivariate ARCH effects

This paper extends Engle's LM test for ARCH affects to multivariate cases. The size and power properties of this multivariate test for ARCH effects in VAR models are investigated based on asymptotic and bootstrap distributions. Using the asymptotic distribution, deviations of actual size from nominal size do not appear to be very excessive. Nevertheless, there is a tendency for the actual size to

Molecular imprinting: Synthetic materials as substitutes for biological antibodies and receptors

Molecular imprinting is a versatile technique providing functional materials able to recognize and in some cases respond to biological and chemical agents of interest. In contrast to biological antibodies, the best known receptors derived from biological combinatorial processes, molecularly imprinted polymers (MIPs) are obtained by template-directed synthesis. Thus, molecular imprinting can more p

A time-variant analysis of fundamental 1/f3 phase noise in CMOS parallel LC-tank quadrature oscillators

This paper presents a rigorous time-variant analysis of the 1/f MOS device noise upconversion into 1/f^3 phase noise for two of the most popular parallel-coupled quadrature CMOS harmonic oscillators. Simple closed-form equations for the fundamental 1/f^3 phase-noise spectrum are derived and validated through SpectreRF simulations, proving that the two topologies display remarkably different sensit

Wash-in kinetics for sevoflurane using a disposable delivery system (AnaConDa (R)) in cardiac surgery patients

The use of volatile anaesthetics has increased in situations where conventional anaesthetic machines are inadequate or unavailable, for example, cardiac surgery and intensive care. The disposable anaesthetic conserving device, AnaConDa (R), allows vaporization of liquid volatile anaesthetics from a syringe pump and rebreathing of exhaled anaesthetic. Clinical use requires understanding of device-s

C-13 incorporation into signature fatty acids as an assay for carbon allocation in arbuscular mycorrhiza

The ubiquitous arbuscular mycorrhizal fungi consume significant amounts of plant assimilated C, but this C flow has been difficult to quantify. The neutral lipid fatty acid 16:1ω 5 is a quantitative signature for most arbuscular mycorrhizal fungi in roots and soil. We measured carbon transfer from four plant species to the arbuscular mycorrhizal fungus Glomus intraradices by estimating C-13 enrich

Bayesian Time Delay Estimation of GNSS Signals in Dynamic Multipath Environments

A sequential Bayesian estimation algorithm for multipath mitigation is presented, with an underlying movement model that is especially designed for dynamic channel scenarios. In order to facilitate efficient integration into receiver tracking loops, it builds upon complexity reduction concepts that previously have been applied within maximum likelihood (ML) estimators. To demonstrate its capabilit

The meaning of preceptorship: nurses' lived experience of being a preceptor

AIM OF THE STUDY: This phenomenological study is aimed at illuminating nurses' lived experience of the process of preceptoring and the meaning of preceptorship in a Swedish context. METHODS: Seventeen nurses from the North of Sweden with varied previous experience of preceptorship volunteered to participate. Their narratives, describing their experience of being a personal preceptor for a student

A potential transmitter architecture for future generation green wireless base station

Current radio frequency power amplifiers in 3G base stations have very high power consumption leading to a hefty cost and negative environmental impact. In this paper, we propose a potential architecture design for future wireless base station. Issues associated with components of the architecture are investigated. The all-digital transmitter architecture uses a combination of envelope elimination

Recommendations for the standardization and interpretation of the electrocardiogram: part I: the electrocardiogram and its technology a scientific statement from the American Heart Association Electrocardiography and Arrhythmias Committee, Council on Clinical Cardiology; the American College of Cardiology Foundation; and the Heart Rhythm Society endorsed by the International Society for Computerized Electrocardiology

This statement examines the relation of the resting ECG to its technology. Its purpose is to foster understanding of how the modern ECG is derived and displayed and to establish standards that will improve the accuracy and usefulness of the ECG in practice. Derivation of representative waveforms and measurements based on global intervals are described. Special emphasis is placed on digital signal

Multiplexed Lipid Dip-Pen Nanolithography on Subcellular Scales for the Templating of Functional Proteins and Cell Culture

Molecular patterning processes taking place in biological systems are challenging to study in vivo because of their dynamic behavior, subcellular size, and high degree of complexity. In vitro patterning of biomolecules using nanolithography allows simplification of the processes and detailed study of the dynamic interactions. Parallel dip-pen nanolithography (DPN) is uniquely capable of integratin

Safety culture on board six Swedish passenger ships

This paper presents the results of a Swedish study on maritime safety culture. The study aims to increase knowledge about the characteristics of safety culture in the maritime setting and the relationship between safety culture and organizational climate. This knowledge can be vital in the process of developing and improving a safety culture. The paper reports the results of safety culture assessm

Allelic polymorphism in MHC class IIB in four populations of Atlantic salmon (Salmo salar)

We sequenced exon 2 of the MHC class II B gene in Atlantic salmon from the Baltic Sea and identified 17 different exon 2 alleles among 22 different restriction fragment length polymorphism haplotypes. The sequences differed at between I and 34 bases. Two different tests were used to estimate the importance of recombination in the generation of new alleles. Recombination events appear to have occur

Marine glacial and interglacial stratigraphy in Vendsyssel, northern Denmark: foraminifera and stable isotopes

The marine Quaternary of Vendsyssel has been studied in a series of new boreholes in the area, and the climatic development is discussed on the basis of foraminiferal assemblages and stable isotopes. The foraminiferal zones are correlated with previously published records from northern Denmark, and the spatial local and regional distribution is discussed in details based on the new evidence. The n

Detection of a t(1;22)(q23;q 12) translocation leading to an EWSR1-PBX1 fusion gene in a myoepithelioma

Chromosome banding as well as molecular cytogenetic methods are of great help in the diagnosis of mesenchymal tumors. Myoepithelial neoplasms of soft tissue including myoepitheliomas, mixed tumors, and parachordomas are diagnoses that have been increasingly recognized the last few years. It is still debated which neoplasms should be included in these morphologically heterogeneous entities, and the

Mechanism of action for N-substituted benzamide-induced apoptosis.

We have analysed the mechanism of action for induction of apoptosis by N-substituted benzamides using declopramide as a lead compound. We show here that declopramide at doses above 250 microM in the mouse 70Z/3 pre-B cell line or in the human promyeolocytic cancer cell line HL60 induced cytochrome c release into the cytosol and caspase-9 activation. The broad spectrum caspase inhibitor zVADfmk and