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31.
32.
Acrylamide exposure was investigated in subgroups of the EPIC study population (510 subjects from 9 European countries, randomly selected and stratified by age, gender, and smoking status) using hemoglobin adducts of acrylamide (HbAA) and its primary metabolite glycidamide (HbGA). Blood samples were analyzed for HbAA and HbGA by HPLC/MS/MS. Statistical models for HbAA and HbGA were developed including body mass index (BMI), educational level, and physical activity. A large variability in acrylamide exposure and metabolism between individuals and country groups was observed with HbAA and HbGA values ranging between 15-623 and 8-377 pmol/g of Hb, respectively. Both adducts differed significantly by country, sex, and smoking status. HbGA values were significantly lower in high alcohol consumers than in moderate consumers. With increasing BMI, HbGA in nonsmokers and HbAA in smokers decreased significantly. In the assessment of potential health effects related to acrylamide exposure, country of origin, BMI, alcohol consumption, sex, and smoking status should be considered.  相似文献   
33.
This study investigated the responses of soil animal communities, soil functioning and humus forms to forest dynamics and solar radiation. We examined changes in invertebrate communities and soil features in two subalpine spruce forests (Eastern Italian Alps, Trento) growing on a calcareous bedrock, with different sun exposures (north and south), each forming a chronosequence of three developmental phases: clearing, regeneration stand (25-year-old trees) and mature stand (170-year-old trees). Our results indicate that the two forest sites differed in solar energy input, soil chemical properties and the relationships between forest dynamics and animal communities. In the north-facing site, soil fauna communities were very similar in the three forest developmental phases. Conversely, in the south-facing site, the composition of invertebrate communities and the diversity of zoological groups varied greatly among developmental phases. The highest abundance of total invertebrates, and mites in particular, occurred in the south-facing mature stands while the south-facing regeneration stand was characterised by higher densities of Collembola, Chilopoda, Symphyla, Protura and Aranea. The structure of communities in clearings was the same as in regeneration stands but with lower invertebrate abundance. Humus forms and soil features changed with developmental phases in both the south- and north-facing sites, although variations were more pronounced in the southern exposure. Mature stands were characterised by high levels of soil organic carbon and nitrogen, C/N values and low pH, the clearings and regeneration stands being characterised by a greater release of mineral nitrogen. The diversity of zoological groups (Shannon–Wiener index) was linearly correlated to soil pH, Humus Index, the amount of organic carbon and the species richness of herbaceous plants. Our results about the composition and the diversity of invertebrate communities are consistent with the observations of other authors studying south-exposed forests growing on different bedrock types, indicating that such relationships are widespread. The higher densities of invertebrates in the south-facing site may be attributed to higher solar radiation, and the positive correlation observed between total soil fauna abundance and solar energy supports the “more individuals” hypothesis that assumes a positive relationship between the number of individuals and energy availability. Possible ways by which forest dynamics control soil invertebrate communities are discussed.  相似文献   
34.
In order to study the salt effect on the wild wheat and durum wheat, three accessions of Aegilops geniculata L. from Ain zana, Zaghouan, and Sbitla and one variety of wheat (Triticum durum L.) have been grown in the INRAT green house and treated with different salt concentrations. The morphological, phenological and yield characters have been measured for each plant and analyzed using SAS software. This study has shown a high degree of variation of these characters mainly related to geographical origin. It was observed also that Sbitla accession was less affected by the imposed salt stress than all the others while Ain zana was the most affected one.  相似文献   
35.
All native fishes living in the Caribbean island rivers are considered diadromous but few species have been validated as diadromous. In Guadeloupe (Lesser Antilles) as well as in the other tropical islands, the riverine habitats are subject to strong anthropogenic pressure due to resource modifications or dams. The management of fish biodiversity requires knowledge concerning their life history traits and behaviour that are still unknown for most species at a local scale and at the whole distribution area of the species. In a Guadeloupe river, we inferred the migratory patterns of four freshwater fishes common to Caribbean rivers by the analysis of otolith microchemistry. We found two species Eleotris perniger (Eleotridae) and Sicydium plumieri (Gobiidae) to be completely amphidromous with a marine larval phase and a freshwater adult phase. Agonostomus monticola (Mugilidae) was also found to be amphidromous in this system. The fourth species Gobiesox cephalus (Gobiesocidae) showed elemental ratios suggesting an estuarine larval phase and was defined as “limited amphidromous”. The identification of such life history traits, with limited dispersion abilities, argues for specific management measures in tropical island rivers at a basin scale for the conservation of biodiversity.  相似文献   
36.
Quinoa is recently introduced to Pakistan as a salt‐tolerant crop of high nutritional value. Open field trials were conducted to evaluate its performance on normal and salinity/sodicity‐degraded lands at two locations of different salinity/sodicity levels, S1 (UAF Farm, Normal Soil), S2 (Paroka Farm UAF, saline sodic), S3 (SSRI Farm, normal) and S4 (SSRI Farm, saline sodic) during 2013–2014. Two genotypes (Q‐2 and Q‐7) were grown in lines and were allowed to grow till maturity under RCBD split‐plot arrangement. Maximum seed yield (3,062 kg/ha) was achieved by Q‐7 at normal field (S1) soil which was statistically similar with yield of same genotype obtained from salt‐affected field S2 (2,870 kg/ha). Furthermore, low yield was seen from both genotypes from both S3 and S4 as compared to S1 and S2. Q‐7 was best under all four conditions. Minimum yield was recorded from Q‐2 (1,587 kg/ha) at S4. Q‐7 had higher SOD, proline, phenolic and K+ contents, and lower Na+ content in leaves as compared to Q‐2. High levels of antioxidants and K+/Na+ of Q‐7 helped to withstand salt stress and might be the cause of higher yields under both normal and salt‐affected soils. Seed quality (mineral and protein) did not decrease considerably under salt‐affected soils even improved seed K+, Mg2+ and Mn2+.  相似文献   
37.
This study was to investigate the effects of Epigallocatechin‐3‐gallate (EGCG) on intestinal morphology, antioxidant capacity and anti‐inflammatory response in heat‐stressed broiler. A total of 192 2‐week‐old Arbour Acres broilers chickens were divided into four groups with six replicates per group and eight chickens per replicate: one thermoneutral control group (28°C, group TN), which was fed the basal diet; and three cyclic high‐temperature groups (35°C from 7:00 to 19:00 hr; 28°C from 19:00 hr to 7:00 hr, heat stress group), which were fed the basal diet supplementation with EGCG 0 mg/kg (group HS0), 300 mg/kg (group HS300) and 600 mg/kg (group HS600). The gut morphology and intestinal mucosal oxidative stress indicators, as well as intestinal barrier‐related gene expression, were analysed. The results showed that compared with group TN, heat stress reduced the villus height (VH), activities of glutathione peroxidase (GSH‐Px), superoxide dismutase (SOD)and catalase (CAT), increased the crypt depth (CD) and malondialdehyde (MDA)content at 21, 28 and 35 days (p < 0.05). After the heat‐stressed broilers were supplemented with EGCG, VH, VH/CD (V/C), and the activities of GSH‐Px, SOD and CAT were increased, and CD and MDA content were reduced compared with those in group HS0 without EGCG supplementation at 21, 28 and 35 days (p < 0.05). The EGCG supplementation promoted the gene expression of nuclear factor‐erythroid 2‐related factor 2 (Nrf2), Claudin‐1, Mucin 2 (Muc2) and alleviated the nuclear factor‐kappa B (NF‐κB) and lipopolysaccharide‐induced tumour necrosis factor (LITAF) gene expression compared with group HS0 (p < 0.05). Moreover, intestinal morphology was strongly correlated with antioxidant ability and inflammatory response. In conclusion, EGCG alleviated the gut oxidative injury of heat‐stressed broilers by enhancing antioxidant capacity and inhibiting inflammatory response.  相似文献   
38.
Tropical Animal Health and Production - Mastitis is the inflammation of the mammary gland due to microbial infiltration causing a reduced mammary function. This study aims at developing a vaccine...  相似文献   
39.
Tropical Animal Health and Production - Corynebacterium pseudotuberculosis is the causative agent of caseous lymphadenitis, a debilitating chronic disease of sheep and goats. Little is known about...  相似文献   
40.
Tropical Animal Health and Production - Fourteen body measurements of 132 adult female camels belonging to three populations Guerzni (60), Khouari (28), and Marmouri (44) reared in 38 herds of 8...  相似文献   
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