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71.
Iani C  Gopher D  Lavie P 《Psychophysiology》2004,41(5):789-798
We ran two experiments to investigate whether peripheral arterial tone reflects changes in mental effort. Finger pulse wave amplitude, interpulse interval, and pulse variability in the mid- and high-frequency bands were recorded by means of a newly developed finger plethysmograph during both rest and cognitive performance. Using a modified version of the Sternberg memory task, we selectively manipulated either the difficulty of the task (Experiment 1) or the subjects' level of engagement in the task (Experiment 2). We found a significant difference in finger pulse wave amplitude between rest and task periods, suggesting that the measure reflects changes in sympathetic activity due to task engagement. In addition, our results suggest that reduced pulse wave amplitude, signaling vasoconstriction, occurs when subjects are investing effort.  相似文献   
72.
Anomalies of both No. 3 chromosomes, of the t(3q?; 3q+) type can be observed in human malignancy as reported previously. It is our experience that this anomaly is found predominantly in myeloproliferative disorders, as a rather rare event, though occurring more frequently than similar exchanges between other homologous chromosomes. Previous claims about a relationship between this anomaly and thrombocytosis could not be confirmed, but the features found in a few patients indicate that further research should be undertaken to clarify this point.  相似文献   
73.
74.
We report three cases of well-differentiated neuroendocrine carcinoma originating primarily in the anterior mediastinum which had been initially investigated by fine-needle aspiration cytology in conjunction with immunocytochemistry and subsequently recognized as thymic in origin. Aspirates consisted of loosely cohesive or aggregated medium sized elements with round to oval nuclei and scanty cytoplasm. in all cases the Romanowsky stain provided an excellent delineation of definite paranuclear inclusion-like structures having a semicircular or discoid appearance which appeared to contain cytokeratin by immunocytochemical studies and were very similar to the intermediate filament paranuclear “buttons” found in neuroendocrine Merkel cell carcinoma of the skin. This appears to be a novel cytologic observation for thymic neuroendocrine carcinoma. We discuss the significance of the above cytologic and immunocytochemical findings and their possible role in the diagnosis of thymic neuroendocrine carcinoma by fine-needle aspiration biopsy. © 1995 Wiley- Liss, Inc.  相似文献   
75.
Introduction: Neuropsychiatric systemic lupus erythematosus (NPSLE) is characterized by a heterogeneity of clinical manifestations. The absence of diagnostic criteria and the lack of clinical trials is a challenge in clinical practice.

Areas covered: A literature review was performed to describe epidemiology, characterization (clinical, immunological, and imaging), diagnosis and treatment of NPSLE. Classification criteria have been the first step towards a uniform definition. More recently, different attribution models have been developed to help to determine if the NP event is due to SLE. Disease activity is a major risk factor for NP events. Cytokines and autoantibodies are associated with NP events, however, only a few studies have identified risk factors for individual NP events.

Expert opinion: Further research needs to search for and validate biomarkers for NPSLE and individual NP events, including neuroimaging findings, attribution models, and serologic markers. This will be a fundamental step in planning randomized control trials in the treatment of NPSLE to improve outcome.  相似文献   

76.
Maternal and Child Health Journal - Dietary patterns can influence maternal and child health outcomes. The study aims to characterize dietary patterns during pregnancy as well as to identify their...  相似文献   
77.
Self-management of health requires skills to obtain, process, understand, and use health-related information. Assessment of adolescents’ functional health literacy requires valid, reliable, and low-burden tools. The main objective of this study was to adapt and study the psychometric properties of the Newest Vital Sign for the Portuguese adolescents’ population (NVS-PTeen). Classic psychometric indicators of reliability and validity were combined with item response theory (IRT) analyses in a cross-sectional survey, complemented with a 3-month test-retest assessment. The NVS-PTeen was self-administered to students enrolled in grades 8 to 12 (12 to 17 years old) in a school setting. Overall, 386 students (191 girls) from 16 classes of the same school participated in the study (mean age = 14.5; SD = 1.5). Internal reliability of the NVS-PTeen was α = 0.60. The NVS-PTeen total score was positively and significantly correlated with Portuguese (r = 0.28) and mathematics scores (r = 0.31), school years (r = 0.31), and age (r = 0.19). Similar to the original scale (for the U.S.), the NVS-PTeen is composed of two dimensions, reading-related literacy and numeracy. Temporal reliability is adequate, though with a learning effect. IRT analyses revealed differences in difficulty and discriminative capacity among items, all with adequate outfit and infit values. Results showed that the NVS-PTeen is valid and reliable, sensible to inter-individual educational differences, and adequate for regular screening of functional health literacy in adolescents.  相似文献   
78.
The present study aims to evaluate the effects of an infant formula supplemented with a mixture of prebiotic short and long chain inulin-type oligosaccharides on health outcomes, safety and tolerance, as well as on fecal microbiota composition during the first year of life. In a prospective, multicenter, randomized, double-blind study, n = 160 healthy term infants under 4 months of age were randomized to receive either an infant formula enriched with 0.8 g/dL of Orafti®Synergy1 or an unsupplemented control formula until the age of 12 months. Growth, fever (>38 °C) and infections were regularly followed up by a pediatrician. Digestive symptoms, stool consistency as well as crying and sleeping patterns were recorded during one week each study month. Fecal microbiota and immunological biomarkers were determined from a subgroup of infants after 2, 6 and 12 months of life. The intention to treat (ITT) population consisted of n = 149 infants. Both formulae were well tolerated. Mean duration of infections was significantly lower in the prebiotic fed infants (p < 0.05). The prebiotic group showed higher Bifidobacterium counts at month 6 (p = 0.006), and higher proportions of Bifidobacterium in relation to total bacteria at month 2 and 6 (p = 0.042 and p = 0.013, respectively). Stools of infants receiving the prebiotic formula were softer (p < 0.05). Orafti®Synergy1 tended to beneficially impact total daily amount of crying (p = 0.0594). Supplementation with inulin-type prebiotic oligosaccharides during the first year of life beneficially modulates the infant gut microbiota towards higher Bifidobacterium levels at the first 6 months of life, and is associated with reduced duration of infections.  相似文献   
79.
Intestinal health relies on the association between the mucosal immune system, intestinal barrier and gut microbiota. Bioactive components that affect the gut microbiota composition, epithelial physical barrier and intestinal morphology were previously studied. The current systematic review evaluated evidence of anthocyanin effects and the ability to improve gut microbiota composition, their metabolites and parameters of the physical barrier; this was conducted in order to answer the question: “Does food source or extract of anthocyanin promote changes on intestinal parameters?”. The data analysis was conducted following the PRISMA guidelines with the search performed at PubMed, Cochrane and Scopus databases for experimental studies, and the risk of bias was assessed by the SYRCLE tool. Twenty-seven studies performed in animal models were included, and evaluated for limitations in heterogeneity, methodologies, absence of information regarding allocation process and investigators’ blinding. The data were analyzed, and the anthocyanin supplementation demonstrated positive effects on intestinal health. The main results identified were an increase of Bacteroidetes and a decrease of Firmicutes, an increase of short chain fatty acids production, a decrease of intestinal pH and intestinal permeability, an increase of the number of goblet cells and tight junction proteins and villi improvement in length or height. Thus, the anthocyanin supplementation has a potential effect to improve the intestinal health. PROSPERO (CRD42020204835).  相似文献   
80.
Childhood obesity has become a major global health problem. Vitamin D deficiency and poor cardiorespiratory fitness are highly prevalent in children with overweight or obesity, but little is known about their relationships. In this study, we aimed to analyze the relationship between serum 25-hydroxyvitamin D (25(OH)D) and cardiorespiratory fitness parameters in prepubertal obese and overweight children. A cross-sectional design with a sample of 57 prepubertal children, aged 9–11 years, with overweight or obesity was used. The fasting concentration of 25(OH)D was analyzed with a chemiluminescent microparticle immunoassay. Fat and lean body masses were determined by using DXA. Maximal oxygen uptake (VO2max) was measured with the maximal treadmill test. A total of 68.4% of the sample had sufficient levels of 25(OH)D. As expected, their cardiorespiratory fitness was poor compared with that of normal-weight children, but 60% of the group exceeded the median obesity-specific reference values. No differences were found between the sexes for relative VO2max or 25(OH)D levels. Moreover, no correlations were found between 25(OH)D and body composition or cardiorespiratory parameters for sex or vitamin D groups. Vitamin D status seems not to be directly related to body composition or cardiorespiratory fitness in prepubertal overweight or obese children.  相似文献   
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