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101.
This study evaluated the health risk due to air pollution in São Paulo State, Brazil, comparing Brazil's standards and the World Health Organization (WHO) air quality guidelines. New methodology was applied considering, as hazard parameters, the maximum average concentrations of SO2, NO2, O3, CO, and PM10 from 2007 to 2011. As exposure parameters, population density and location sensitivity were considered. A health risk index based on fuzzy logic was performed to integrate the selected parameters, giving the likelihood of reaching different risk levels. Data gathering and spatial representation of parameters and risk scores were performed by means of geographic information system (GIS). Highest values of risk were observed in the Metropolitan Area of São Paulo and near the cities of Cubatão and Piracicaba, associated to vehicular and industrial emissions and sugar cane burning. Discussions about the need to revise national air quality standards have intensified over the past years. Generally, indices used for air quality do not consider the population exposed. This study showed the integration of GIS with fuzzy logic methodology to be a useful tool for health risk assessment. When evaluating the risk, exposure parameters must be intrinsically considered to enhance the importance of population vulnerability when assessing environmental problems, especially in emerging economies.  相似文献   
102.

Objective

Research suggests autoimmune processes to be involved in psychiatric disorders. We aimed to address the prevalence and incidence of autoimmune diseases in a large Finnish patient cohort with anorexia nervosa, bulimia nervosa, and binge eating disorder.

Methods

Patients (N = 2342) treated at the Eating Disorder Unit of Helsinki University Central Hospital between 1995 and 2010 were compared with general population controls (N = 9368) matched for age, sex, and place of residence. Data of 30 autoimmune diseases from the Hospital Discharge Register from 1969 to 2010 were analyzed using conditional and Poisson regression models.

Results

Of patients, 8.9% vs. 5.4% of control individuals had been diagnosed with one or more autoimmune disease (OR 1.7, 95% CI 1.5–2.0, P<0.001). The increase in endocrinological diseases (OR 2.4, 95% CI 1.8–3.2, P<0.001) was explained by type 1 diabetes, whereas Crohn''s disease contributed most to the risk of gastroenterological diseases (OR 1.8, 95% CI 1.4–2.5, P<0.001). Higher prevalence of autoimmune diseases among patients with eating disorders was not exclusively due to endocrinological and gastroenterological diseases; when the two categories were excluded, the increase in prevalence was seen in the patients both before the onset of the eating disorder treatment (OR 1.5, 95% CI 1.1–2.1, P = 0.02) and at the end of the follow-up (OR 1.4, 95% CI 1.1–1.8, P = 0.01).

Conclusions

We observed an association between eating disorders and several autoimmune diseases with different genetic backgrounds. Our findings support the link between immune-mediated mechanisms and development of eating disorders. Future studies are needed to further explore the risk of autoimmune diseases and immunological mechanisms in individuals with eating disorders and their family members.  相似文献   
103.
104.
Germplasm from closely related diploid relatives of tobacco (Nicotiana tabacum L.) could be of value for continued genetic modification of this species and for mapping quantitative trait loci (QTLs). We examined near isogenic tobacco lines and hybrids differing for an introgressed genomic region from N. tomentosa Ruiz and Pavon designated as Many Leaves that exhibits a large influence on leaf number and correlated traits. Within a ‘Red Russian’ genetic background, the region acted in an additive to partially dominant fashion to delay flowering time, and increase leaf number, plant height, and green leaf yield. Evidence of epistasis was observed as the region affected these traits to varying degrees in diverse near isogenic hybrids. Fifteen amplified fragment length polymorphism (AFLP) markers of N. tomentosa origin were mapped within a single linkage group of 34.5 cM using a population of 207 BC1F1 individuals segregating for Many Leaves. Composite interval mapping produced 2–LOD confidence intervals for likely QTL positions influencing leaf number (3.1 cM region), plant height (2.9 cM region), and days to flowering (3.3 cM region). These intervals were overlapping. Results demonstrate that genomic regions with large genetic effects can be transferred to tobacco from closely related diploid relatives, and that sufficient recombination within these regions may permit mapping of genes controlling quantitative traits. Materials and results described here may be useful in future research to gain insight on the genetic control of the transition from vegetative to reproductive development in Nicotiana.  相似文献   
105.
Plant diversity fosters productivity in natural ecosystems. Biodiversity effects might increase agricultural yields at no cost in additional inputs. However, the effects of diversity on crop assemblages are inconsistent, probably because crops and wild plants differ in a range of traits relevant to plant–plant interactions. We tested whether domestication has changed the potential of crop mixtures to over‐yield by comparing the performance and traits of major crop species and those of their wild progenitors under varying levels of diversity. We found stronger biodiversity effects in mixtures of wild progenitors, due to larger selection effects. Variation in selection effects was partly explained by within‐mixture differences in leaf size. Our results indicate that domestication might disrupt the ability of crops to benefit from diverse neighbourhoods via reduced trait variance. These results highlight potential limitations of current crop mixtures to over‐yield and the potential of breeding to re‐establish variance and increase mixture performance.  相似文献   
106.
Molecular and Cellular Biochemistry - The present study investigated the therapeutic effect of curcumin on bleomycin (BLM)-induced alterations in glycoprotein components in the fibrotic lungs....  相似文献   
107.
Plant phenological studies in the Mediterranean have traditionally focused on the limits that summer drought exerts over plant seasonal behaviour. However, Mediterranean areas also occur across extensive regions under cooler climates. Here, we analyse phenological data of Mediterranean woody species from winter-cold sites to address the following questions: what is the most limiting period of the year for phenological development? How, and how synchronously, do different phenophases adjust to the bimodal limitation of summer drought and winter cold? How ample is the suit of phenological strategies that are successful for Mediterranean phanaerophytes from cool areas?  相似文献   
108.
Milla R  Reich PB 《Annals of botany》2011,107(3):455-465

Background and Aims

Despite long-held interest, knowledge on why leaf size varies widely among species is still incomplete. This study was conducted to assess whether abiotic factors, phylogenetic histories and multi-trait interactions act together to shape leaf size.

Methods

Fifty-seven pairs of altitudinal vicariant species were selected in northern Spain, and leaf area and a number of functionally related leaf, shoot and whole plant traits were measured for each pair. Structural equation modelling helped unravel trait interactions affecting leaf size, and Mantel tests weighed the relative relevance of phylogeny, environment and trait interactions to explain leaf size reduction with altitude.

Key Results

Leaves of highland vicariants were generally smaller than those of lowlands. However, the extent of leaf size reduction with increasing altitude was widely variable among genera: from approx. 700 cm2 reduction (96 % in Polystichum) to approx. 30 cm2 increase (37 % in Sorbus). This was partially explained by shifts in leaf, shoot and whole plant traits (35–64 % of explained variance, depending on models), with size/number trade-offs more influential than shifts in leaf form and leaf economics. Shifts in traits were more important than phylogenetic distances or site-specific environmental variation in explaining the degree of leaf size reduction with altitude.

Conclusions

Ecological filters, constraints due to phylogenetic history (albeit modest in the study system), and phenotypic integration contribute jointly to shape single-trait evolution. Here, it was found that phenotypic change was far more important than shared ancestry to explaine leaf size differences of closely related species segregated along altitudes.  相似文献   
109.
The augmentation of neurotransmitter and hormone release produced by ouabain inhibition of plasmalemmal Na+/K+-ATPase (NKA) is well established. However, the mechanism underlying this action is still controversial. Here we have shown that in bovine adrenal chromaffin cells ouabain diminished the mobility of chromaffin vesicles, an indication of greater number of docked vesicles at subplasmalemmal exocytotic sites. On the other hand, ouabain augmented the number of vesicles undergoing exocytosis in response to a K+ pulse, rather than the quantal size of single vesicles. Furthermore, ouabain produced a tiny and slow Ca2+ release from the endoplasmic reticulum (ER) and gradually augmented the transient elevations of the cytosolic Ca2+ concentrations ([Ca2+]c) triggered by K+ pulses. These effects were paralleled by gradual increments of the transient catecholamine release responses triggered by sequential K+ pulses applied to chromaffin cell populations treated with ouabain. Both, the increases of K+-elicited [Ca2+]c and secretion in ouabain-treated cells were blocked by thapsigargin (THAPSI), 2-aminoethoxydiphenyl borate (2-APB) and caffeine. These results are compatible with the view that ouabain may enhance the ER Ca2+ load and facilitate the Ca2+-induced-Ca2+ release (CICR) component of the [Ca2+]c signal generated during K+ depolarisation. This could explain the potentiating effects of ouabain on exocytosis.  相似文献   
110.
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