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91.
92.

Background  

Self-tests are available to consumers for more than 25 conditions, ranging from infectious diseases to cardiovascular risk factors. Self-tests are defined as in-vitro tests on body materials such as blood, urine, faeces, or saliva that are initiated by consumers to diagnose a particular disorder or risk factor without involving a medical professional. In 2006, 16% of a sample of Dutch Internet users had ever used at least one self-test and 17% intended to use a self-test in the future. The objectives of this study are to determine (1) the frequency of self-test use, (2) the consumers' reasons for using or not using a self-test, (3) the information that is used by self-testers in the different self-test stages and the consumers' interpretation of the quality of this information, (4) the consumers' response to self-test results in terms of their confidence in the result, reassurance by the test result, and follow-up behaviour, (5) the information consumers report to need in the decision making process of using or not using a self-test, and in further management on the basis of the self-test result, and (6) the quality of the currently available consumer information on a selected set of self-tests.  相似文献   
93.
A questionnaire survey (QS) among stakeholders in Tanzania had shown that in-kind drug donations (DDs) are important to boost the drug supply system. Major problems were their insufficient quantity for sustainable treatment and the discrepancy between the needs of the recipients and the donors' supply. Objectives in this study were to discuss these findings and to learn from key informants (KIs) how to improve the DD process. Data were collected through KI interviews in 2001/2002.A 30% gap in drug supply has to be bridged by DDs. KIs confirmed the importance of the World Health Organisation and Tanzanian DD guidelines as a tool for good donation practice and emphasized the role of the government in their implementation. They requested that donors meet the recipient country's regulatory requirements. In contrast to QS respondents, KIs did not view DD quality as a minor problem, and proposed that DD quality should be adapted to the national quality assurance procedures. DD processes could be improved through (a) effective implementation of DD guidelines as an aid for decision-making and for quality assurance, (b) availability of data to improve communication between donors and recipients, (c) transparency between recipients and donors and (d) clearly defined accountability.  相似文献   
94.

BACKGROUND

The etiology of infantile hypertrophic pyloric stenosis (IHPS) remains a mystery. Some suspected risk factors include birth rank, maternal age, sex, family history and monozygosity in twins. Various theories attempt to explain the etiology of IHPS. Scientific research suggests that enteric neuronal damage and nitric oxide synthase dysfunction may be implicated, but the consensus is that environmental modification must exist to account for the variability in its occurrence.

METHOD

Four cases of concordant occurrences of IHPS in twins were examined to determine the history and outcome of IHPS development in twins. Three sets were dizygotic and one was monozygotic. Of the eight infants, three were female, including the one monozygotic pair. In all four cases, a time lag existed between the development of symptomatic onset of IHPS in twin A and twin B. In one set, sonographic confirmation, performed because of IHPS diagnosis in the twin sibling, occurred concurrently with onset of vomiting, leading to early surgery before fluid and electrolyte imbalances developed.

CONCLUSIONS

Despite the lack of agreement as to whether the cause of IHPS is genetic, environmental or both, the high concordance rate seen in twins is indisputable. Thus, the empirical evidence provides credence to consider examining the asymptomatic co-twin when one of the twins presents with IHPS.  相似文献   
95.
96.

Introduction

To date, there is no universal varicella vaccination in the Netherlands. We studied the seroprevalence of varicella zoster virus (VZV) specific antibodies and determinants for seropositivity among participants of a serosurveillance study, conducted in 2006/2007 among Dutch inhabitants 0–79 years of age.

Materials and methods

Serological testing of 6386 blood samples for VZV was performed with a fluorescent bead-based multiplex immunoassay. Seroprevalence and geometric mean concentration (GMC) were weighted for age, sex, ethnicity, and urbanization rate to the total Dutch population. Determinants for VZV seropositivity were identified among children younger than 6 years of age using a logistic regression model.

Results

The overall seroprevalence of VZV specific antibodies in the Dutch population was 94.6% (95% CI: 93.2–96.0%). This seroprevalence increased rapidly with age: at 6 years of age, more than 95% were seropositive. Determinants associated with lower VZV seropositivity were: young age, first-generation non-Dutch ethnicity, and low frequency of attendance at a day care center or nursery school. The GMC increased with age and was lower for women than for men from the age of 20 years onwards.

Conclusions

This study confirmed that VZV infection occurs at a younger age in the Netherlands compared to other countries, which might explain the low disease burden due to varicella. Introduction of universal varicella vaccination is not a foregone conclusion in the Netherlands. Changes in migration and day care usage will influence the age-specific risk on varicella and should therefore be monitored. Further research might elucidate the sex differences in VZV specific GMC.  相似文献   
97.
98.
99.
Abnormalities in the brain generally manifest on MRI as changes in shape (morphometry) or changes in the nature of the tissue (signal intensity). Voxel Based Morphometry (VBM) is a whole brain quantitative way of assessing morphometric changes. Voxel Based Relaxometry (VBR) directly assesses signal intensity changes in quantitative maps of T2 relaxation time, but this requires specialised multiple-echo acquisition sequences that are not usually available at clinical sites. This paper introduces and assesses an objective voxel-based statistical method for evaluation of signal intensity in groups of routinely acquired qualitative images. We call the method Voxel-Based Iterative Sensitivity (VBIS) analysis. It adaptively optimises the relative global scaling of images to maximise sensitivity to regional effects. We apply and validate the method of analysis for T2-weighted images of the human brain. To validate the method, it was directly compared with VBR by extracting T2-weighted images of a single echo from multi-echo T2 relaxometry acquisitions from a group of 24 patients with left hemisphere hippocampal sclerosis and 97 healthy controls. Expected signal abnormalities in the patients were detectable with VBIS-T2, confirming the feasibility of the technique. This opens the door to the use of a voxel-based analysis approach on the vast amount of T2-weighted image data that has been and is being acquired on MRI scanners. When a quantitative modality is not available, VBIS can be an effective way to quantify differences between groups. We expect the method could also assist quantitative analysis of other qualitative modalities such as T1-weighted MRI, SPECT and CT.  相似文献   
100.
Computed tomography (CT) has emerged in the past decade as an important tool in the evaluation of cardiac pathology, specifically in the diagnosis of coronary artery disease (CAD). This article will review the technique and role of CT and CT angiography (CTA) in modern cardiovascular care. CT techniques are described, as are the applications of CT in the assessment of CAD including both calcium scoring and CTA. Although CAD is the mainstay of cardiac CT, important noncoronary cardiac applications including the evaluation of cardiac function, masses, valvular disease, and pericardial disease, are reviewed as well. The nursing care of the patient undergoing CTA is reviewed as are future developments within this field.  相似文献   
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