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排序方式: 共有2234条查询结果,搜索用时 15 毫秒
1.
Luana Lopes Padilha Elcio Oliveira Vianna Andressa Talícia Machado Vale Joelma Ximenes Prado Teixeira Nascimento Antônio Augusto Moura da Silva Cecilia Claudia Costa Ribeiro 《Pediatric allergy and immunology》2020,31(5):480-488
Studies on the exposure of children to sugar-sweetened beverages (SSBs) at an early age may contribute to better understand the common causes and the temporal order of the relationships between obesity and asthma in early childhood. The objective of this study was to estimate the association between SSB and child asthma traits in the 2nd year of life, modeling direct and indirect pathways mediated by the highest BMI-z of the child and allergic inflammation. Data from the BRISA cohort, São Luís-MA, Brazil (n = 1140), were obtained from the baseline and from the follow-up performed at the 2nd year of life. The main explanatory variable was the calories from added sugars in SSBs as a percentage of the total daily energy intake. The outcome child asthma traits was a latent variable deduced from four indicators: medical diagnosis of asthma, wheezing, emergency visit due to intense wheezing, and medical diagnosis of rhinitis. A high percentage of daily calories from sugars added to SSBs was directly associated with higher values of child asthma traits (standardized coefficient (SC = 0.073; P = .030)). High levels of eosinophils were also directly associated with child asthma traits (SC = 0.118; P = .049). No mediation pathways were observed via greater BMI-z or eosinophil counts. Therefore, early exposure of children to SSB may contribute to increased risk of childhood asthma, preceding the link between sugar consumption and overweight/obesity, not yet evident in children in the first 2 years of life. 相似文献
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P Yagupsky E Shahak A Tal J E Bearman I Zuili S Shany 《The Journal of pediatrics》1992,120(5):802-805
Lipid profiles were determined in three groups of children: children with asthma receiving long-term therapy with slow-releasing theophylline, children with asthma not treated with theophylline, and a control group of children without asthma. Total cholesterol, high-density lipoprotein cholesterol, and apolipoprotein A levels and the high-density lipoprotein/low-density lipoprotein ratio were significantly higher among theophylline-treated children. The observed changes do not seem to increase the risks of atherosclerotic coronary artery disease. 相似文献
4.
Integrated plasma cortisol concentration in children with asthma receiving long-term inhaled corticosteroids. 总被引:2,自引:0,他引:2
We assessed the effect of long-term therapy with inhaled beclomethasone dipropionate (BDP) on the pituitary-adrenal axis, by measuring the integrated concentration (IC) of plasma cortisol in eight children with asthma (age, 6-16 years) who regularly used inhaled BDP in doses ranging from 8 to 26.5 micrograms/kg (200-450 micrograms/day) for 6 months to 4 years. The control group included six children (age, 6-16 years) who had the IC of plasma cortisol measured as part of an endocrinological evaluation and were found to be healthy. Cortisol concentration was measured in blood samples collected continuously over a 24-hr period. Mean IC of plasma cortisol in the study group was significantly lower than in the healthy controls (mean +/- SD, 4.9 +/- 3.3 vs 9.1 +/- 1.9 micrograms/mL; P less than 0.02). Cortisol response to 0.25 mg ACTH (iv) was abnormal in one of the eight BDP-treated patients. No correlation was found between IC of plasma cortisol and the BDP dose, severity of asthma, height percentile, or the Tanner stage. We conclude that long-term therapy, even with relatively conventional doses of inhaled BDP may cause reduction in the normal physiological secretion of cortisol. The clinical relevance of low IC of plasma cortisol is not clear, but it may reflect partial suppression of the pituitary-adrenal axis. 相似文献
5.
Human mesenchymal stem cells from adipose tissue: Differentiation into hepatic lineage. 总被引:4,自引:0,他引:4
R Taléns-Visconti A Bonora R Jover V Mirabet F Carbonell J V Castell M J Gómez-Lechón 《Toxicology in vitro》2007,21(2):324-329
Adipose tissue represents an accessible source of mesenchymal stem cells (ADSCs), with similar characteristics to bone marrow-derived stem cells. The aim of this work was to investigate the transdifferentiation of ADSCs into hepatic lineage cells in vitro. ADSCs were obtained from human adipose tissue from lipectomy. Cells were grown in medium containing 15% AB human serum. Cultures were serum deprived for two days and exposed to a two-step protocol with two different media using growth factors and cytokines. Hepatic differentiation was assessed by RT-PCR of liver-marker genes. ADSCs exhibited a fibroblastic morphology that changed to a cuboidal shape when cells differentiated. Expression of liver genes increased when using one of the two studied media consisting of DMEM supplemented with HGF, bFGF and nicotinamide for 14 days. The results indicate that, under certain specific inducing conditions, ADSCs can be induced to differentiate into hepatic lineage in vitro. Adipose tissue may be an ideal source of high amounts of autologous stem cells. 相似文献
6.
Hagit Cohen Joseph Zohar Michael A Matar Zeev Kaplan Amir B Geva 《Neuropsychopharmacology》2005,58(8):640-650
BACKGROUND: Unsupervised fuzzy clustering (UFC) analysis is a mathematical technique that groups together objects in the multidimensional feature space according to a specified similarity measurement, thereby yielding clusters of similar data points that can be represented by a set of prototypes or centroids. METHODS: Since clinical studies of mental disorders distinguish between affected and unaffected individuals, we designed an inclusion/exclusion criteria (cutoff behavioral criteria [CBC]) approach for animal behavioral studies. The effect of classifying the study population into clearly affected versus clearly unaffected individuals according to behaviors on two behavioral paradigms was statistically significant. RESULTS: Here the raw data from previous studies were subjected to UFC algorithms as a means of objectively testing the validity of the concept of the CBC for our experimental model. The first UFC algorithm yielded two clearly discrete clusters, found to consist almost exclusively of the exposed animals in the one and unexposed animals in the other. The second algorithm yielded three clusters corresponding to animals designated as clearly affected, partially affected, and clearly unaffected. The algorithm for physiological data in addition to behavioral data failed to elicit discrete clusters. CONCLUSIONS: The UFC analysis yielded data that support the conceptual contention of the CBC and lends additional validity to our previous behavioral studies. 相似文献
7.
Nir Lubezky Ur Metser Ravit Geva Richard Nakache Einat Shmueli Joseph M. Klausner Einat Even-Sapir Arie Figer Menahem Ben-Haim 《Journal of gastrointestinal surgery》2007,11(4):472-478
Background Recent data confirmed the importance of 18-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) in the selection of patients with colorectal hepatic metastases for surgery.
Neoadjuvant chemotherapy before hepatic resection in selected cases may improve outcome. The influence of chemotherapy on
the sensitivity of FDG-PET and CT in detecting liver metastases is not known.
Methods Patients were assigned to either neoadjuvant treatment or immediate hepatic resection according to resectability, risk of
recurrence, extrahepatic disease, and patient preference. Two-thirds of them underwent FDG-PET/CT before chemotherapy; all
underwent preoperative contrast-enhanced CT and FDG-PET/CT. Those without extensive extrahepatic disease underwent open exploration
and resection of all the metastases according to original imaging findings. Operative and pathological findings were compared
to imaging results.
Results Twenty-seven patients (33 lesions) underwent immediate hepatic resection (group 1), and 48 patients (122 lesions) received
preoperative neoadjuvant chemotherapy (group 2). Sensitivity of FDG-PET and CT in detecting colorectal (CR) metastases was
significantly higher in group 1 than in group 2 (FDG-PET: 93.3 vs 49%, P < 0.0001; CT: 87.5 vs 65.3, P = 0.038). CT had a higher sensitivity than FDG-PET in detecting CR metastases following neoadjuvant therapy (65.3 vs 49%,
P < 0.0001). Sensitivity of FDG-PET, but not of CT, was lower in group 2 patients whose chemotherapy included bevacizumab compared
to patients who did not receive bevacizumab (39 vs 59%, P = 0.068).
Conclusions FDG-PET/CT sensitivity is lowered by neoadjuvant chemotherapy. CT is more sensitive than FDG-PET in detecting CR metastases
following neoadjuvant therapy. Surgical decision-making requires information from multiple imaging modalities and pretreatment
findings. Baseline FDG-PET and CT before neoadjuvant therapy are mandatory.
The abstract was presented before the 58th Cancer Symposium of the Society of Surgical Oncology, Atlanta, GA, USA, 2005, and
before the 2005 Congress of the American Hepato-Pancreato-Biliary Association, Fort-Lauderdale, FL, USA. 相似文献
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PURPOSE: Two studies are presented here. Study 1 was aimed at evaluating whether the voice characteristics of women who use birth control pills that contain different progestins differ from the voice characteristics of a control group. Study 2 presents a meta-analysis that combined the results of Study 1 with those from 3 recent studies that compared voices of women who use and do not use birth control pills. METHOD: In Study 1, voice samples from 30 women with no history of voice training, who use pills with different progestins (drospirenone, desogestrel, gestodene), and 10 women who do not use the pill were recorded at specific time points across the menstrual cycle and were analyzed acoustically. In Study 2, results from Study 1 were analyzed jointly with results from three recent studies, which used similar methodologies. RESULTS: Results of Study 1 did not reveal acoustic differences in sustained phonation of vowels across the pill groups and controls. Results of the meta-analysis performed in Study 2 indicated that pill users exhibited lower jitter and shimmer values on sustained vowels, whereas no difference of fundamental frequency was observed among women who use the pill. CONCLUSIONS: These results support findings from previous studies, which suggested that no adverse effect on voice was detected among nonprofessional speakers who use new-generation monophasic birth control pills, for the measures studied. Furthermore, results of the meta-analysis suggested that some acoustic properties of the voice, which are reflected in perturbation measures in sustained vowels, may be improved among women who use the pill. 相似文献
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