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841.
Objective To assess whether hyponatremia in acute neurological patients is associated with the syndrome of inappropriate antidiuretic
hormone secretion (SIADH) or with the cerebral salt-wasting syndrome (CSWS).
Design Clinical, controlled, prospective study.
Setting Department of intensive care of a tertiary care academic hospital.
Patients Forty acute neurological patients with hyponatremia suggesting SIADH or CSWS (20) or with normonatremia (20).
Interventions None.
Measurements and main results Measurement of clinical and biological variables. Measurement of blood, plasma, and red blood cell volumes to discriminate
SIADH and CSWS. Renal, adrenal and thyroid functions were normal in all patients. Average blood, plasma, and red blood cell
volumes were 54, 37 and 17 ml/kg in control patients and 54, 37 and 18 ml/kg in hyponatremic patients, respectively.
Conclusions The adequate blood volumes in hyponatremic patients confirm the diagnosis of SIADH and do not support the concept of CSWS.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
842.
Husmann L Wiegand M Valenta I Gaemperli O Schepis T Siegrist PT Namdar M Wyss CA Alkadhi H Kaufmann PA 《The international journal of cardiovascular imaging》2008,24(5):511-518
Objective The aim of this study was to compare the diagnostic accuracy of myocardial perfusion imaging (MPI) by positron emission tomography
(PET) with the diagnostic accuracy of MPI by single photon emission computed tomography (SPECT) in two comparable patient
cohorts, using coronary angiography (CA) as the standard of reference. Methods A “SPECT-group” of 80 patients (15 female, 65 male; mean age 60 ± 9 years) and a “PET-group” of 70 patients (14 female, 56
male; mean age 57 ± 10 years) underwent a one day stress/rest examination either with attenuation-corrected 13N-ammonia PET or attenuation-corrected 201TlCl SPECT or 99mTc-hexakis-methoxy-isobutyl-isonitril (MIBI) SPECT. PET and SPECT results were semiquantitatively graded using a 6-segment
heart model. All patients underwent CA, and stenoses were graded as a diameter reduction ≥50%. Results Coronary findings between both groups did not significantly differ at CA. For the SPECT-group overall sensitivity and specificity
for localisation of stenoses was 77% and 84%. Respective values for the PET-group were 97% and 84%. The specificity of MPI
by SPECT in the detection of ischemia was 74% and 91% for MPI by PET. The diagnostic accuracy of MPI improves when the individual
coronary dominance and previous coronary revascularisations are taken into account. Conclusion MPI by 13N-ammonia PET is more sensitive in the detection and localisation of coronary stenoses, and more specific in the detection
of ischemia than MPI by 201TlCl/99mMIBI SPECT. 相似文献
843.
Schraml C Clasen S Schwenzer NF Koenigsrainer I Herberts T Claussen CD Pereira PL 《Abdominal imaging》2008,33(6):643-651
Background To determine the accuracy of contrast-enhanced multislice computed tomography (CT) in the assessment of treatment success
immediately after CT-guided radiofrequency (RF) ablation.
Methods 26 patients with 38 Colorectal liver metastasis (CRM) were treated by CT-guided RF ablation. Pre-contrast and portal phase
CT features before and immediately after ablation were retrospectively evaluated quantitatively and qualitatively: Influence
of attenuation characteristics, safety margin, congruency between tumor and coagulation, and morphological criteria (shape,
margin distinction, margin configuration, and margin continuity) were investigated. Findings were statistically analyzed with
regard to local tumor progression.
Results Mean observation period for follow-up scans was 6.4 months (range: 3–40 months). Attenuation characteristics, safety margin,
and congruency had no significant effect on the probability of local tumor progression. Coagulations whose margin was categorized
as “discontinuous” were significantly more often associated with local recurrence (p = 0.038). No significant influence on local recurrence could be detected regarding coagulation shape, margin distinction,
and configuration.
Conclusion Computed tomography imaging immediately after RF ablation allows for morphological characterization of the coagulation and
provides a valid baseline status for follow-up imaging. However, in CRM, morphological image criteria and attenuation characteristics
have limited predictive value for immediate detection of persistent tumor. 相似文献
844.
Background
Data on the effect of contraceptive methods, other than the condom, on HIV acquisition is not clear. The aim of this study was to describe hormonal contraceptive use, sexual behaviour and HIV prevalence among women in Cameroon in order to provide baseline information for future analytical studies. 相似文献845.
Annabelle M Wilson Anthea M Magarey Nadia Mastersson 《The international journal of behavioral nutrition and physical activity》2008,5(1):5
Background
Food behaviours, attitudes, environments and knowledge are relevant to professionals in childhood obesity prevention, as are dietary patterns which promote positive energy balance. There is a lack of valid and reliable tools to measure these parameters. The aim of this study was to determine the reliability and relative validity of a child nutrition questionnaire assessing all of these parameters, used in the evaluation of a community-based childhood obesity prevention project. 相似文献846.
847.
848.
849.
850.
Metabolomics is one of the newer omics fields, and has enabled researchers to complement genomic and protein level analysis of disease with both semi-quantitative and quantitative metabolite levels, which are the chemical mediators that constitute a given phenotype. Over more than a decade, methodologies have advanced for both targeted (quantification of specific analytes) as well as untargeted metabolomics (biomarker discovery and global metabolite profiling). Untargeted metabolomics is especially useful when there is no a priori metabolic hypothesis. Liquid chromatography coupled to mass spectrometry (LC-MS) has been the preferred choice for untargeted metabolomics, given the versatility in metabolite coverage and sensitivity of these instruments. Resolving and profiling many hundreds to thousands of metabolites with varying chemical properties in a biological sample presents unique challenges, or pitfalls. In this review, we address the various obstacles and corrective measures available in four major aspects associated with an untargeted metabolomics experiment: (1) experimental design, (2) pre-analytical (sample collection and preparation), (3) analytical (chromatography and detection), and (4) post-analytical (data processing). 相似文献