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941.
Background
Adolescents are at risk for acquiring sexually transmitted infections (STIs). However, test rates among adolescents in the Netherlands are low and effective interventions that encourage STI testing are scarce. Adolescents who attend vocational schools are particularly at risk for STI. The purpose of this study is to inform the development of motivational health promotion messages by identifying the psychosocial correlates of STI testing intention among adolescents with sexual experience attending vocational schools. 相似文献942.
943.
rCBF differences between panic disorder patients and control subjects during anticipatory anxiety and rest. 总被引:8,自引:0,他引:8
Marjolein L Boshuisen Gert J Ter Horst Anne M J Paans A A T Simone Reinders Johan A den Boer 《Neuropsychopharmacology》2002,52(2):126-135
BACKGROUND: Our goal was to identify brain structures involved in anticipatory anxiety in panic disorder (PD) patients compared to control subjects. METHODS: Seventeen PD patients and 21 healthy control subjects were studied with H(2)(15)O positron emission tomography scan, before and after a pentagastrin challenge. RESULTS: During anticipatory anxiety we found hypoactivity in the precentral gyrus, the inferior frontal gyrus, the right amygdala, and the anterior insula in PD patients compared to control subjects. Hyperactivity in patients compared to control subjects was observed in the parahippocampal gyrus, the superior temporal lobe, the hypothalamus, the anterior cingulate gyrus, and the midbrain. After the challenge, the patients showed decreases compared to the control subjects in the precentral gyrus, the inferior frontal gyrus, and the anterior insula. Regions of increased activity in the patients compared to the control subjects were the parahippocampal gyrus, the superior temporal lobe, the anterior cingulate gyrus, and the midbrain. CONCLUSIONS: The pattern of regional cerebral blood flow activations and deactivations we observed both before and after the pentagastrin challenge was the same, although different in intensity. During anticipatory anxiety more voxels were (de)activated than during rest after the challenge. 相似文献
944.
Ileana Hancu Johan R C van der Maarel Fernando E Boada 《Magnetic resonance in medicine》2002,47(1):68-74
A new method for selectively detecting sodium ions in anisotropic environments is presented. A spin-lock (SL) sequence, followed by a coherence transfer pulse, generates rank-two zero-quantum coherences, and converts them into observable transverse magnetization. The quadrupolar polarization is only generated when there are residual quadrupolar couplings in the sample, and provided the SL field strength is comparable to these couplings. This filter has proved to be more efficient than a double-quantum magic-angle (DQ-MA) filter in generating observable signal from ions in anisotropic media in both a nasal bovine cartilage sample and a liquid crystalline DNA sample. Finally, the SL filtering technique does not rely on a flip angle effect for the selection of the desired signal component, as does a DQ-MA filter, and may therefore prove desirable in an imaging experiment, due to its better tolerance to phase and flip angle imperfections. 相似文献
945.
Anna Sidorchuk Emilie E. Agardh Olatunde Aremu Johan Hallqvist Peter Allebeck Tahereh Moradi 《Cancer causes & control : CCC》2009,20(4):459-471
Objective To investigate the associations between various socioeconomic indicators and lung cancer incidence.
Methods We searched PubMed and EMBASE databases for studies on socioeconomic position (SEP) and lung cancer incidence published through
October 2007. Random-effect model was used to pool the risk estimates from the individual studies. We stratified the analysis
by adjustment strategy to investigate the influence of smoking on socioeconomic gradient in lung cancer incidence.
Results Out of 3,288 citations, we identified 64 studies eligible for inclusion. Compared to the highest SEP level, we observed an
overall increased risk in lung cancer incidence among people with low educational SEP (61%), low occupational SEP (48%), and
low income-based SEP (37%). The negative social gradient for lung cancer incidence remained for most of the possible sets
of pooled estimates obtained in subgroup analyses for occupational and educational SEP with less consistency for SEP based
on income in studies adjusted and unadjusted for smoking. No evidence of publication bias was apparent.
Conclusion Lung cancer incidence was associated with low educational, occupational, and income-based SEP. The association, adjusted or
unadjusted for smoking, points out the importance of social position to be addressed in all discussions on cancer preventive
measures.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
This work was performed in the Department of Public Health Sciences, Division of Social Medicine/Epidemiology, Karolinska
Institutet, Stockholm, Sweden. 相似文献
946.
947.
Johan L. Gabrielsson Per Johansson Ulf Bondesson Mats Karlsson Lennart K. Paalzow 《Journal of pharmacokinetics and pharmacodynamics》1986,14(4):381-395
The disposition of pethidine (meperidine) in the pregnant rat is described by means of a physiological flow model. The model includes arterial and venous blood, brain, fat, fetal, hepatic, intestinal, muscular, pulmonar, and renal tissues. The concentration-time profiles of pethidine calculated by the model are consistent with experimental data, except for the brain and renal tissues, where the model predicts initially higher concentrations. Simulations are carried out to further explore the contribution from different organs on the kinetics in blood and tissues. The tissue-to-blood partition coefficients vary over a range from 5 to 316, where fat has the lowest and liver the highest after a correction is made due to hepatic extraction. Rapid uptake occurs into highly perfused organs such as brain, kidneys, liver, and lungs, followed by fetus, intestines, muscle, and fat. Data indicate no marked membrane resistance to pethidine of the investigated organs, except for fetal tissues, but rather a perfusion-limited uptake. Simulations suggest that muscles and adipose tissue play an important role in the rat, becoming the major reservoir of drug during the intermediate and terminal elimination phase, respectively. Volume of distribution and the biological half-life agree with reported findings. Pethidine is subject to a high systemic blood clearance, which exceeds the total hepatic blood flow in the rat. No degradation of pethidine is found in blood, and therefore a pulmonary expression for pethidine clearance is added as a potential source of pethidine elimination. The elimination of pethidine after a single i.v. bolus dose is found to be dependent on simulated changes in cardiac output and hepatic blood flow. A simulation is performed with the scaled model to mimic the human concentration-time profiles in maternal blood and brain tissues and fetal tissue during repetitive doses of pethidine. 相似文献
948.
949.
Biologically relevant bioassays are needed to test various endocrine disrupters (EDs). A mouse follicle culture model could allow measuring steroidogenic enzyme function in combination with oocyte growth and meiotic maturation using routine methodology. Three steroidogenesis-disrupting ‘model’ chemicals were tested; vorozole (VOR), aminoglutethimide (AMG), and ketoconazole (KCZ). Along with visual assessment of follicular growth, differentiation and oocyte growth and maturation by conventional light microscopy, steroid secretion measurements allowed to confirm literature findings from in vivo animal studies and more complex in vitro tests. The bioassay was applied for a dose–response study of mono(2-ethylhexyl)phthalate (MEHP), a chemical known to disrupt several steroidogenic enzymes. This bioassay was able to confirm an increased inactivation of E2 to E1 and an induced precocious progesterone increase, implying that MEHP can disrupt follicle differentiation and impact the reproductive axis. This in vitro ovarian model allows to reduce animal use by performing synchronous culture of large numbers of early preantral ovarian mouse follicles and is informative on multiple fertility-related endpoints. 相似文献
950.
Eva Brink Yvonne Brändström Christina Cliffordsson Johan Herlitz Björn W. Karlson 《Journal of advanced nursing》2008,64(6):587-594
Aim. This paper is a report of a study to explore health problems, physical and mental functioning, and physical activity in working‐age patients after myocardial infarction, in order to assess the possible effects of these factors on return to work. Background. A diagnosis of myocardial infarction may discourage patients from continuing an active working life. Enabling myocardial infarction patients to return to work has benefits for both individuals and society. Methods. A convenience sample was recruited of 88 patients, ≤65 years of age, who had suffered a myocardial infarction. Assessments of employment, health‐related quality of life and physical activity (footsteps per day) were conducted in 2005–2006, 4–6 months after myocardial infarction. To explore data and compare groups, t‐tests were applied. Logistic regression analyses were performed to identify variables that best predicted return to work. Results. Differences were identified between individuals who were employed after myocardial infarction and those who were not. Those not in work scored lower on variables related to the physical dimension of health‐related quality of life and on physical activity. Logistic regression revealed that a multivariate model including age, physical dimension of health‐related quality of life and footsteps per day predicted return to work in 68% of all cases (R2 = 0·344). Conclusion. Low physical health and low physical activity after myocardial infarction negatively affect returning to work. These findings stress the importance of clinical assessment of myocardial infarction patients’ daily physical activity and physical functioning. 相似文献