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排序方式: 共有1004条查询结果,搜索用时 15 毫秒
31.
Gabriele B. Murrmann Femke H.M. van Vollenhoven Loven Moodley 《Journal of thoracic disease》2014,6(3):237-248
A new solid solitary pulmonary nodule (SPN) is a common feature in the daily practice of physicians, pulmonologists and thoracic surgeons. The etiology and consequently the diagnostic approach is very different in various parts of the world. Identification of malignant nodules is the universal goal to proceed to a potential curable therapy. In countries with a low incidence of inflammatory disease and a high incidence of lung cancer the diagnostic work up includes a positron emission tomography (PET) scan or PET-computer tomography (CT) as a main pillar. In countries with a high incidence of inflammatory and infectious disease and a low incidence in lung cancer this diagnostic work up needs to be adapted. In these settings a PET scan has a limited role and tissue diagnosis, whether with a trans-thoracic, trans-bronchial biopsy or a video-assisted wedge resection is the most targeted approach to determine or exclude malignancy. The evaluation of a solid SPN in the two different situations is outlined in our algorithm. Recommendations stress the value of clinical judgement in different settings, determination of probabilities of malignancy, cost-effective use of diagnostic tools and evaluation of various management alternatives according to the risk profile and the patients preferences.KEYWORDS : Solitary pulmonary nodule (SPN), diagnostic work up, lung neoplasms, inflammatory lung disease, algorithm 相似文献
32.
Lower birth weight because of fetal growth restriction is associated with higher blood pressure later in life, but the extent to which preterm birth (<37 completed weeks' gestation) or very low birth weight (<1500 g) predicts higher blood pressure is less clear. We performed a systematic review of 27 observational studies that compared the resting or ambulatory systolic blood pressure or diagnosis of hypertension among children, adolescents, and adults born preterm or very low birth weight with those born at term. We performed a meta-analysis with the subset of 10 studies that reported the resting systolic blood pressure difference in millimeters of mercury with 95% CIs or SEs. We assessed methodologic quality with a modified Newcastle-Ottawa Scale. The 10 studies were composed of 1342 preterm or very low birth weight and 1738 term participants from 8 countries. The mean gestational age at birth of the preterm participants was 30.2 weeks (range: 28.8-34.1 weeks), birth weight was 1280 g (range: 1098-1958 g), and age at systolic blood pressure measurement was 17.8 years (range: 6.3-22.4 years). Former preterm or very low birth weight infants had higher systolic blood pressure than term infants (pooled estimate: 2.5 mm Hg [95% CI: 1.7-3.3 mm Hg]). For the 5 highest quality studies, the systolic blood pressure difference was slightly greater, at 3.8 mm Hg (95% CI: 2.6-5.0 mm Hg). We conclude that infants who are born preterm or very low birth weight have modestly higher systolic blood pressure later in life and may be at increased risk for developing hypertension and its sequelae. 相似文献
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34.
Brain-Computer Interface (BCI) research and (future) applications raise important ethical issues that need to be addressed to promote societal acceptance and adequate policies. Here we report on a survey we conducted among 145 BCI researchers at the 4th International BCI conference, which took place in May–June 2010 in Asilomar, California. We assessed respondents’ opinions about a number of topics. First, we investigated preferences for terminology and definitions relating to BCIs. Second, we assessed respondents’ expectations on the marketability of different BCI applications (BCIs for healthy people, BCIs for assistive technology, BCIs-controlled neuroprostheses and BCIs as therapy tools). Third, we investigated opinions about ethical issues related to BCI research for the development of assistive technology: informed consent process with locked-in patients, risk-benefit analyses, team responsibility, consequences of BCI on patients’ and families’ lives, liability and personal identity and interaction with the media. Finally, we asked respondents which issues are urgent in BCI research. 相似文献
35.
Femke?DH?Koedijk Birgit?HB?van BenthemEmail author Eliane?MDC?Vrolings Wim?Zuilhof Marianne?AB?van der Sande 《Emerging themes in epidemiology》2014,11(1):12
Background
Men having sex with men (MSM) remain the largest high-risk group involved in on-going transmission of sexually transmitted infections (STI), including HIV, in the Netherlands. As risk behaviour may change with age, it is important to explore potential heterogeneity in risks by age. To improve our understanding of this epidemic, we analysed the prevalence of and risk factors for selected STI in MSM attending STI clinics in the Netherlands by age group.Methods
Analysis of data from the national STI surveillance system for the period 2006–2012. Selected STI were chlamydia, gonorrhoea, infectious syphilis and/or a new HIV infection. Logistic regression was used to identify factors associated with these selected STI and with overall STI positivity. Analyses were done separately for MSM aged younger than 25 years and MSM aged 25 years and older.Results
In young MSM a significant increase in positivity rate was seen over time (p?<?0.01), mainly driven by increasing gonorrhoea diagnoses, while in MSM aged 25 and older a significant decrease was observed (p?<?0.01). In multivariate analyses for young MSM, those who were involved in commercial sex were at higher risk (OR: 1.5, 95% CI: 1.2-1.9). For MSM aged 25 years and older this was not the case. Having a previous negative HIV test was protective among older MSM compared to those not tested for HIV before (OR: 0.8, 95% CI: 0.8-0.8), but not among younger MSM.Conclusions
MSM visiting STI clinics remain a high-risk group for STI infections and transmission, but are not a homogenous group. While in MSM aged older than 25 years, STI positivity rate is decreasing, positivity rate in young MSM increased over time. Therefore specific attention needs to be paid towards targeted counselling and reaching particular MSM sub-groups, taken into account different behavioural profiles.36.
37.
Hepatitis C virus (HCV) has emerged as a sexually transmitted infection among HIV-positive men who have sex with men (MSM) in high-income countries. Little is reported about HCV awareness among MSM, although this is essential for developing targeted prevention strategies. We, therefore, studied HCV awareness and knowledge among HIV-positive and HIV-negative MSM from the Amsterdam Cohort Studies (ACS). During two visits, 1 year apart and starting in October 2007, MSM from the ACS answered questions regarding HCV awareness, knowledge of HCV transmission (7 items), complications (8 items) and sexual risk behaviour. We examined the percentage of HCV awareness and correctly answered knowledge items, and whether awareness and knowledge improved significantly over time. Using logistic regression, we studied whether HIV status and sexual risk behaviour were associated with awareness. Seventy percent (312/444) of HIV-negative and 80% (74/92) of HIV-positive MSM reported to have ever heard of HCV on the first visit. Overall, awareness increased with 9% between the first and second visit (p < 0.001). In multivariate analysis the association of group sex with HCV awareness was borderline significant (OR 1.49, 95% CI 0.97–2.30). Compared with knowledge of transmission routes, knowledge of complications appeared to be limited. In the ACS, awareness of HCV is high, particularly among those reporting group sex, an important risk factor for HCV transmission. The majority of participants had good knowledge of transmission routes, but limited knowledge of complications of chronic HCV infection. HCV prevention messages could be strengthened, therefore, by further addressing the complications of HCV infection. 相似文献
38.
39.
Background
The Netherlands Armed Forces (NLAF) are using −80°C deep-frozen thrombocyte concentrate (DTC) since 2001. The aim of this study is to investigate the effect of storage duration and alterations in production/measurement techniques on DTC quality. It is expected that DTC quality is unaffected by storage duration and in compliance with the European guidelines for fresh and cryopreserved platelets.Study Design and Methods
Pre-freeze and post-thaw product platelet content and recovery were collected to analyze the effects of dimethyl sulfoxide (DMSO) type, duration of frozen storage (DMSO-1 max 12 years and DMSO-2 frozen DTC max 4 years at −80°C) and type of plasma used to suspend DTC. Coagulation characteristics of thawed DTC, plasma and supernatant of DTC (2× 2500 G) were measured with Kaolin thromboelastography (TEG) and phospholipid (PPL) activity assay.Results
Platelet content and recovery of DTC is ±10%–15% lower in short-stored products and remained stable when stored beyond 0.5 years. Thawed DTC (n = 1724) were compliant to the European guidelines (98.1% post-thaw product recovery ≥50% from original product, 98.3% ≥200 × 109 platelets/unit). Compared to DMSO-1, products frozen with DMSO-2 showed ±8% reduced thaw–freeze recovery, a higher TEG clot strength (MA 58 [6] vs. 64 [8] mm) and same ±11 s PPL clotting time. The use of cold-stored thawed plasma instead of fresh thawed plasma did not influence product recovery or TEG-MA.Discussion
Regardless of alterations, product quality was in compliance with European guidelines and unaffected by storage duration up to 12 years of −80°C frozen storage. 相似文献40.
Lieke S Kamphuis Femke Bonte‐Mineur Jan A van Laar P Martin van Hagen Paul L van Daele 《Journal of bone and mineral research》2014,29(11):2498-2503
Granulomas in sarcoidosis express high levels of 1α‐hydroxylase, an enzyme that catalyzes the hydroxylation of 25‐OH vitamin D to its active form, 1,25(OH)2 vitamin D. Overproduction of 1α‐hydroxylase is held responsible for the development of hypercalcemia in sarcoidosis patients. Corticosteroids are used as first‐line treatment in organ‐threatening sarcoidosis. In this light, osteoporosis prevention with calcium and vitamin D (CAD) supplementation is often warranted. However, sarcoidosis patients are at risk for hypercalcemia, and CAD supplementation affects the calcium metabolism. We studied calcium and vitamin D disorders in a large cohort of sarcoidosis patients and investigated if CAD supplementation is safe. Retrospectively, data of 301 sarcoidosis patients from July 1986 to June 2009 were analyzed for serum calcium, 25‐hydroxy vitamin D (25‐(OH)D), 1,25‐dihydroxy vitamin D (1,25(OH)2D), and use of CAD supplementation. Disease activity of sarcoidosis was compared with serum levels of vitamin D. Hypercalcemia occurred in 8%. A significant negative correlation was found between 25‐(OH)D and disease activity of sarcoidosis measured by somatostatin receptor scintigraphy. In our study, 5 of the 104 CAD‐supplemented patients developed hypercalcemia, but CAD supplementation was not the cause of hypercalcemia. Patients without CAD supplementation were at higher risk for developing hypercalcemia. During CAD supplementation, no hypercalcemia developed as a result of supplementation. Hypovitaminosis D seems to be related with more disease activity of sarcoidosis and, therefore, could be a potential risk factor for disease activity of sarcoidosis. Thus, vitamin D–deficient sarcoidosis patients should be supplemented. © 2014 American Society for Bone and Mineral Research. 相似文献