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161.

Objective

Offering calories on restaurant websites might be particularly important for consumer meal planning, but the availability of and ease of accessing this information are unknown.

Methods

We assessed websites for the top 100 U.S. chain restaurants to determine the availability of and ease of access to calorie information as well as website design characteristics. We also examined potential predictors of calorie availability and ease of access.

Results

Eighty-two percent of restaurants provided calorie information on their websites; 25% presented calories on a mobile-formatted website. On average, calories could be accessed in 2.35±0.99 clicks. About half of sites (51.2%) linked to calorie information via the homepage. Fewer than half had a separate section identifying healthful options (46.3%), or utilized interactive meal planning tools (35.4%). Quick service/fast casual, larger restaurants, and those with less expensive entrées and lower revenue were more likely to make calorie information available. There were no predictors of ease of access.

Conclusion

Calorie information is both available and largely accessible on the websites of America’s leading restaurants. It is unclear whether consumer behavior is affected by the variability in the presentation of calorie information.  相似文献   
162.
As pollination biology undergoes unprecedented growth as a discipline, confusion in the use of terms has become increasingly common. The need for a flexible yet unambiguous terminology has become urgent. As an example we discuss how the term “pollination efficiency” is used differently by 18 studies, and “pollinator effectiveness” by seven others. Here we present flowcharts of two general models of pollination systems (biotic and abiotic) that trace all the events from pollen production to development of seed or fruit, and we develop a lexicon for the quantities of pollen, processes of transfers (to a vector, to a stigma), and ratios of quantities that are of interest in studies of pollination and mating systems. An appendix includes a glossary of the definitions we suggest.  相似文献   
163.
Monosialoganglioside (GM1) is a neuroprotective agent that has been reported to scavenge free radicals generated during reperfusion and to protect receptors and enzymes from oxidative damage. However, only a few studies have attempted to investigate the effects of GM1 on enzymatic antioxidant defenses of the brain. In the present study, we evaluate the effects of the systemic administration of GM1 on the activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px), and on spontaneous chemiluminescence and total radical-trapping potential (TRAP) in cerebral cortex of rats ex vivo. The effects of GM1 on CAT activity and spontaneous chemiluminescence in vitro were also determined.

Animals received two injections of GM1 (50?mg/kg, i.p.) or saline (0.85% NaCl, i.p.) spaced 24?h apart. Thirty minutes after the second injection the animals were sacrificed and enzyme activities and spontaneous chemiluminescence and TRAP were measured in cell-free homogenates. GM1 administration reduced spontaneous chemiluminescence and increased catalase activity ex vivo, but had no effect on TRAP, SOD or GSH-Px activities. GM1, at high concentrations, reduced CAT activity in vitro. We suggest that the antioxidant activity of GM1 ganglioside in the cerebral cortex may be due to an increased catalase activity.  相似文献   
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165.
It has been established that substantial amounts of fungal mass accumulate in standing decaying smooth cordgrass (Spartina alterniflora) marshes in the southeastern United States (e.g., in standing decaying leaf blades with a total fungal organic mass that accounts for about 20% of the decay system organic mass), but it has been hypothesized that in marshes farther north this is not true. We obtained samples of autumnal standing decaying smooth cordgrass from sites in Florida to Maine over a 3-year period. The variation in latitude could not explain any of the variation in the living fungal standing crop (as determined by ergosterol content) or in the instantaneous rates of fungal growth (as determined by acetate incorporation into ergosterol at a standard temperature, 20°C), which led to the conclusion that the potential levels of fungal production per unit of naturally decaying grass are not different in northern and southern marshes. Twenty-one percent of the variation in the size of the living fungal standing crop could be explained by variation in the C/N ratio (the higher the C/N ratio the smaller the fungal crop), but the C/P ratio was not related to the size of the fungal crop. Instantaneous rates of fungal growth were negatively related to the size of the living fungal crop (r = −0.35), but these rates were not correlated with C/nutrient ratios. The same two predominant species of ascomycetes (one Phaeosphaeria species and one Mycosphaerella species) were found ejecting ascospores from standing decaying smooth cordgrass blades at all of the sites examined from Florida to Maine.  相似文献   
166.
Interleukin‐8 (CXCL8, IL‐8) is a proinflammatory chemokine important for the regulation of inflammatory and immune responses via its interaction with G‐protein coupled receptors, including CXC receptor 1 (CXCR1). CXCL8 exists as both a monomer and as a dimer at physiological concentrations, yet the molecular basis of CXCL8 interaction with its receptor as well as the importance of CXCL8 dimer formation remain poorly characterized. Although several biological studies have indicated that both the CXCL8 monomer and dimer are active, biophysical studies have reported conflicting results regarding the binding of CXCL8 to CXCR1. To clarify this problem, we expressed and purified a peptide (hCXCR1pep) corresponding to the N‐terminal region of human CXCR1 (hCXCR1) and utilized nuclear magnetic resonance (NMR) spectroscopy to interrogate the binding of wild‐type CXCL8 and a previously reported mutant (CXCL8M) that stabilizes the monomeric form. Our data reveal that the CXCL8 monomer engages hCXCR1pep with a slightly higher affinity than the CXCL8 dimer, but that the CXCL8 dimer does not dissociate upon binding hCXCR1pep. These investigations also showed that CXCL8 is dynamic on multiple timescales, which may help explain the versatility in this interleukin for engaging its target receptors.  相似文献   
167.
168.
Cerebral cavernous malformations (CCMs) are vascular abnormalities that may cause seizures, intracerebral haemorrhages, and focal neurological deficits. Familial form shows an autosomal dominant pattern of inheritance with incomplete penetrance and variable clinical expression. Three genes have been identified causing familial CCM: KRIT1/CCM1, MGC4607/CCM2, and PDCD10/CCM3. Aim of this study is to report additional PDCD10/CCM3 families poorly described so far which account for 10-15% of hereditary cerebral cavernous malformations. Our group investigated 87 consecutive Italian affected individuals (i.e. positive Magnetic Resonance Imaging) with multiple/familial CCM through direct sequencing and Multiplex Ligation-Dependent Probe Amplification (MLPA) analysis. We identified mutations in over 97.7% of cases, and PDCD10/CCM3 accounts for 13.1%. PDCD10/CCM3 molecular screening revealed four already known mutations and four novel ones. The mutated patients show an earlier onset of clinical manifestations as compared to CCM1/CCM2 mutated patients. The study of further families carrying mutations in PDCD10/CCM3 may help define a possible correlation between genotype and phenotype; an accurate clinical follow up of the subjects would help define more precisely whether mutations in PDCD10/CCM3 lead to a characteristic phenotype.  相似文献   
169.
170.
Cerebral white matter injury in premature infants, known as periventricular leukomalacia (PVL), is common after hypoxia-ischemia (HI). While ionotropic glutamate receptors (iGluRs) can mediate immature white matter injury, we have previously shown that excitotoxic injury to premyelinating oligodendrocytes (preOLs) in vitro can be attenuated by group I metabotropic glutamate receptor (mGluR) agonists. Thus, we evaluated mGluR expression in developing white matter in rat and human brain, and tested the protective efficacy of a central nervous system (CNS)-penetrating mGluR agonist on injury to developing oligodendrocytes (OLs) in vivo. Group I mGluRs (mGluR1 and mGluR5) were strongly expressed on OLs in neonatal rodent cerebral white matter throughout normal development, with highest expression early in development on preOLs. Specifically at P6, mGluR1 and mGLuR5 were most highly expressed on GalC-positive OLs compared to neurons, axons, astrocytes and microglia. Systemic administration of (1S,3R) 1-aminocyclopentane-trans-1,3,-dicarboxylic acid (ACPD) significantly attenuated the loss of myelin basic protein in the white matter following HI in P6 rats. Assessment of postmortem human tissue showed both mGluR1 and mGluR5 localized on immature OLs in white matter throughout development, with mGluR5 highest in the preterm period. These data indicate group I mGluRs are highly expressed on OLs during the peak period of vulnerability to HI and modulation of mGluRs is protective in a rodent model of PVL. Group I mGluRs may represent important therapeutic targets for protection from HI-mediated white matter injury.  相似文献   
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