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101.
Nutrition research, like most biomedical disciplines, adopted and often uses experimental approaches based on Beadle and Tatum’s one gene—one polypeptide hypothesis, thereby reducing biological processes to single reactions or pathways. Systems thinking is needed to understand the complexity of health and disease processes requiring measurements of physiological processes, as well as environmental and social factors, which may alter the expression of genetic information. Analysis of physiological processes with omics technologies to assess systems’ responses has only become available over the past decade and remains costly. Studies of environmental and social conditions known to alter health are often not connected to biomedical research. While these facts are widely accepted, developing and conducting comprehensive research programs for health are often beyond financial and human resources of single research groups. We propose a new research program on essential nutrients for optimal underpinning of growth and health (ENOUGH) that will use systems approaches with more comprehensive measurements and biostatistical analysis of the many biological and environmental factors that influence undernutrition. Creating a knowledge base for nutrition and health is a necessary first step toward developing solutions targeted to different populations in diverse social and physical environments for the two billion undernourished people in developed and developing economies.  相似文献   
102.
We studied the effect of a forest edge management quasi-experiment on hazel dormouse (Muscardinus avellanarius) nest numbers in the reproductive season in the Netherlands. We found that the number of nests increased significantly from 2009 to 2013 in managed edges after clearing 75–100 % of mature trees, with a peak in the second year, whereas those in unmanaged edges decreased. In addition, we studied habitat characteristics in forest edges and hedgerows, and found a positive effect of a high upper shrub layer and a high abundance of blackberry (Rubus fruticosus agg. and Rubus spp.), rowan (Sorbus aucuparia) and common hawthorn (Crataegus monogyna) on nest densities. Based on these results, we propose a potential dormouse management strategy that extends conventionally advocated coppice management for regions with well-developed forest edges by (i) postulating a blackberry-oriented landscape restoration approach and (ii) using clearing of mature trees as a tool to boost local dormouse populations in forest edges that have become unsuitable as dormouse habitat due to vegetational succession.  相似文献   
103.
104.

Background

Same-day diagnosis based on histology is increasingly being offered to patients suspected of breast cancer. We evaluated to which extent same-day diagnosis affected diagnostic accuracy and patients'' anxiety levels during the diagnostic phase.

Patients and methods

All 759 women referred for same-day evaluation of suspicious breast lesions between November 2011–March 2013 were included. Diagnostic accuracy was assessed by linking all patients to the national pathology database to identify diagnostic discrepancies, in which case slides were reviewed. Patients'' anxiety was measured in 127 patients by the State Trait and Anxiety Inventory on six moments during the diagnostic workup and changes over time (< = 1 week) were analyzed by mixed effect models.

Results

Core-needle biopsy was indicated in 374/759 patients (49.3%) and in 205/759 (27%) patients, invasive or in situ cancer was found. Final diagnosis on the same day was provided for 606/759 (79.8%) patients. Overall, 3/759 (0.4%) discordant findings were identified. Anxiety levels decreased significantly over time from 45.2 to 30.0 (P = <0.001). Anxiety levels decreased from 44.4 to 25.9 (P = <0.001) for patients with benign disease, and remained unchanged for patients diagnosed with malignancies (48.6 to 46.7, P = 0.933). Time trends in anxiety were not affected by other patient or disease characteristics like age, education level or (family) history of breast cancer.

Conclusion

Same-day histological diagnosis is feasible in the vast majority of patients, without impairing diagnostic accuracy. Patients'' anxiety rapidly decreased in patients with a benign diagnosis and remained constant in patients with malignancy.  相似文献   
105.
It has been shown that dominant individuals sustain eye-contact when non-consciously confronted with angry faces, suggesting reflexive mechanisms underlying dominance behaviors. However, dominance and submission can be conveyed and provoked by means of not only facial but also bodily features. So far few studies have investigated the interplay of body postures with personality traits and behavior, despite the biological relevance and ecological validity of these postures. Here we investigate whether non-conscious exposure to bodily expressions of anger evokes reflex-like dominance behavior. In an interactive eye-tracking experiment thirty-two participants completed three social dominance tasks with angry, happy and neutral facial, bodily and face and body compound expressions that were masked from consciousness. We confirmed our predictions of slower gaze-aversion from both non-conscious bodily and compound expressions of anger compared to happiness in high dominant individuals. Results from a follow-up experiment suggest that the dominance behavior triggered by exposure to bodily anger occurs with basic detection of the category, but not recognition of the emotional content. Together these results suggest that dominant staring behavior is reflexively driven by non-conscious perception of the emotional content and triggered by not only facial but also bodily expression of anger.  相似文献   
106.
To reduce the volume of drinks and the risk of overconsumption, health professionals recommend the use of tall skinny instead of short wide glasses. Yet the results of the present study contradict this health advice. Participants who generously filled up a glass with lemonade served 9% more in tall narrow compared with short wide glasses (p<0.05). In addition, when pouring a small amount (i.e., a shot), participants poured 3% more in a short wide than in a tall narrow glass (p<0.05). Elongation may bias the perceived volume that is poured but also the perceived volume of the free space in the glass. We hypothesised that shifting attention from the bottom to the brim of the glass when filling it close to capacity might reverse the glass elongation effect on the quantity poured. This hypothesis was tested, by investigating two pouring tasks that differed in the required focus of attention. When the instruction was to match a reference volume, participants poured more liquid in the short wide compared with the tall narrow glass (p<0.05). The effect of glass elongation on poured volume was the opposite when the instruction was to leave space in the glasses for the reference volume. It seems likely that task and individual factors affect the pourer''s viewing strategy and thus may determine the direction of the glass elongation effect on the volume poured.  相似文献   
107.
Tyrosine kinases are important regulators of synaptic strength. Here, we describe a key component of the synaptic vesicle release machinery, Munc18‐1, as a phosphorylation target for neuronal Src family kinases (SFKs). Phosphomimetic Y473D mutation of a SFK phosphorylation site previously identified by brain phospho‐proteomics abolished the stimulatory effect of Munc18‐1 on SNARE complex formation (“SNARE‐templating”) and membrane fusion in vitro. Furthermore, priming but not docking of synaptic vesicles was disrupted in hippocampal munc18‐1‐null neurons expressing Munc18‐1Y473D. Synaptic transmission was temporarily restored by high‐frequency stimulation, as well as by a Munc18‐1 mutation that results in helix 12 extension, a critical conformational step in vesicle priming. On the other hand, expression of non‐phosphorylatable Munc18‐1 supported normal synaptic transmission. We propose that SFK‐dependent Munc18‐1 phosphorylation may constitute a potent, previously unknown mechanism to shut down synaptic transmission, via direct occlusion of a Synaptobrevin/VAMP2 binding groove and subsequent hindrance of conformational changes in domain 3a responsible for vesicle priming. This would strongly interfere with the essential post‐docking SNARE‐templating role of Munc18‐1, resulting in a largely abolished pool of releasable synaptic vesicles.  相似文献   
108.
109.
In the present study we investigated whether age-related changes in the composition and functional properties of murine CD4+ T cells are reflected in vivo by a changed humoral response to influenza vaccine in aged mice. After the primary immunization, the titers of influenza-specific IgM, IgG1, IgG2a, and IgG2b, but not of IgG3 and IgE, were significantly reduced in aged mice compared to young mice. Treatment of aged mice with anti-IFN-γ, anti-IL-4, or anti-IL-10 resulted in levels of IgM and IgG1 comparable to those found in young mice, whereas IgG2a and IgG2b were further decreased. After the booster immunization IgE was significantly enhanced in aged mice, whereas no differences were observed with regard to the other isotypes. During the primary response in young mice, anti-IFN-γ stimulated IgG1 and IgE, whereas an inhibition of IgG2a, IgG2b, and IgG3 was observed. Anti-IL-4 caused a decrease only in IgG3 while anti-IL-10 increased IgM and IgG1 and decreased IgG2b and IgG3. During the primary response in aged mice, all anti-cytokine antibodies enhanced IgM and IgG1 while IgE was only enhanced by anti-IL-10. By contrast, IgG3 was inhibited by anti-IFN-γ and anti-IL-10. Anti-cytokine treatment of young mice increased all isotypes, except IgG3, in the secondary response, whereas the secondary response in aged mice was largely insensitive to anti-cytokine treatment. These data therefore support the idea that the in vivo effects of cytokines on isotype switching are dependent on the differentiation stage of B cells which may be different in young and aged mice.  相似文献   
110.
An improved method for preparing partially digested tomato DNA has been developed, that is suitable for YAC cloning. It involves (i) isolation of high molecular-weight DNA from agarose-embedded leaf protoplasts, (ii) controlled partial digestion in situ using Eco RI endonuclease in the presence of Eco RI methylase (M. Eco RI), and (iii) fractionation of the partial digest on a Clamped Homogeneous Electric Fields (CHEF) gel. Unlike methods commonly used for generating partial digests, the present method allows one to produce digests in which the bulk of restriction fragments are of the desired size. Use of these partial digests in constructing YAC libraries of the tomato lines Moneymaker- Cf4 and VFNT Cherry resulted in libraries (total 21 060 clones, 5.5 genome equivalents) in which 80% of the YACs have inserts between 200 and 600 kb. Both libraries have been screened with selected RFLP markers linked to the Cladosporium fulvum Cf4 locus on chromosome 1, using a three-dimensional PCR-based screening technique. To this end, the RFLP markers have been sequenced to allow for the synthesis of specific primers. Thus, for each marker tested several YAC clones have been isolated, including a family of clones that carry leucine-rich repeat sequences located around the Cf4/ Cf9 locus.  相似文献   
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