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31.
OBJECTIVE: To determine the nutrient composition of complementary foods consumed by 6-12-month-old South African infants. DESIGN: Nutrient intake was determined for infants who were recruited to participate in a randomised controlled trial using a single 24-hour dietary recall. SETTING/SUBJECTS: Infants aged 6-12 months (n=475) residing in The Valley of a Thousand Hills, a rural area in KwaZulu-Natal, South Africa. RESULTS: Energy and protein intakes from complementary foods were adequate. Infants who consumed infant products (commercially available fortified infant cereals/ready-to-eat canned baby foods/formula milk powder) had significantly higher intakes of calcium, iron, zinc, vitamin A, thiamine, riboflavin, niacin, vitamin B6, vitamin B12 and vitamin C than infants who did not consume any infant products. For infants who consumed infant cereals (n=142), these cereals provided 51% of total iron intake. Infant cereals provided more than 25% of total intake for magnesium, thiamine, niacin and vitamin B12. For infants consuming ready-to-eat canned baby foods (n=77), these products contributed less than 15% of total intake for all the micronutrients. The nutrient density of the complementary diet was less than half the desired density for calcium, iron and zinc. Animal products were consumed by 17% of infants, 26% consumed dairy products and 18% consumed vitamin-A-rich fruit and vegetables during the 24-hour recall period. CONCLUSION: The nutrient composition of complementary foods among rural South African infants was inadequate, especially for iron, zinc and calcium. Strategies should be developed to improve the nutritional quality of their diets.  相似文献   
32.
G. Mathys 《EPPO Bulletin》1977,7(3):601-629
L'alignement sur des méthodes normalisées reconnues constitue une simplification considérable du travail pour l'industrie et les instances officielles chargées dévaluer l'efficacité des nouveaux pesticides. Les résultats obtenus en application d'une méthode commune deviennent comparables et les extrapolations ou fractionnements de l'expérimentation sont alors relativement faciles. La France, en 1952 déjà, puis la République Fédérale d'Allemagne ont été parmi les premiers en Europe à reconnaître toute la valeur de létablissement de méthodes agréées par les services officiels et l'industrie. De son côté, le Comité Européen de Recherche sur les Mauvaises Herbes (EWRC) s'est penché sur létude des possibilités de parvenir à une entente sur la façon dévaluer l'efficacité des herbicides, alors que I'OEPP a commencé en 1971 ses travaux sur les rodenticides, insecticides, acaricides et nématicides, ainsi que sur les affections fongiques. Depuis, 5 méthodes intéressant 7 espèces de rongeurs ont été adoptées par les 35 pays membres de I'OEPP et publiées, alors que 5 méthodes concernant les champignons et 10 méthodes les insectes et acariens sont à l'impression; par ailleurs, 29 méthodes font présentement l'objet détudes appro-fondies. Depuis 1976, des contacts ont été pris avec l'ASTM (American Society for Testing and Materials) dans le dessein de parvenir à une harmonisation des technologies à l'échelle inter-régionale.  相似文献   
33.
Colibacillosis results from infection with avian pathogenic Escherichia coli bacteria. Healthy broilers are resistant to inhaled E. coli, but previous infection with vaccine or virulent strains of Infectious Bronchitis Virus (IBV) predisposes birds for severe colibacillosis. The aim of this study was to investigate how IBV affects the course of events upon infection with E. coli. Broilers were inoculated with IBV H120 vaccine virus or virulent M41 and challenged 5 days later with E. coli 506. A PBS and E. coli group without previous virus inoculation were included. Sections of trachea, lung and airsacs were stained for CD4, CD8, gammadelta-TCR, alphabeta1-TCR, and for macrophages (KUL-01) and both pathogens. Changes in the mucociliary barrier of trachea, lung and airsacs did not predispose for bacterial superinfection. The disease in the lungs of the E. coli group and both IBV/E. coli groups was similar. Lesions in the airsacs were more pronounced and of longer duration in the IBV/E. coli groups. The immunocytological changes differed substantially between the E. coli group and both IBV/E. coli groups. In trachea, lungs and airsacs the CD4+ and CD8+ populations were significantly larger than in the E. coli and PBS groups. In the lungs and the airsacs the macrophages were more numerous in the IBV/E. coli and the E. coli groups than in the PBS group. The presence of high numbers of T cells and macrophages in IBV infected birds most likely induced an altered immune response, which is responsible for the enhanced clinical signs of colibacillosis.  相似文献   
34.
Climate change has become a serious threat for crop productivity worldwide. The increased frequency of heat waves strongly affects reproductive success and thus yield for many crop species, implying that breeding for thermotolerant cultivars is critical for food security. Insight into the genetic architecture of reproductive heat tolerance contributes to our fundamental understanding of the stress sensitivity of this process and at the same time may have applied value. In the case of tomato (Solanum lycopersicum), germplasm screenings for thermotolerance have often used yield as the main measured trait. However, due to the complex nature of yield and the relatively narrow genetic variation present in the cultivated germplasm screened, there has been limited progress in understanding the genetic basis of reproductive heat tolerance. Extending the screening to wild accessions of related species that cover a range of climatic conditions might be an effective approach to find novel, more tolerant genetic resources. The purpose of this study was to provide insight into the sensitivity of individual reproductive key traits (i.e. the number of pollen per flower, pollen viability and style protrusion) to heat-wave like long-term mild heat (LTMH), and determine the extent to which genetic variation exists for these traits among wild tomato species. We found that these traits were highly variable among the screened accessions. Although no overall thermotolerant species were identified, several S. pimpinellifolium individuals outperformed the best performing cultivar in terms of pollen viability under LTMH. Furthermore, we reveal that there has been local adaptation of reproductive heat tolerance, as accessions from lower elevations and higher annual temperature are more likely to show high pollen viability under LTMH.  相似文献   
35.
OBJECTIVE: To describe a method of computerized ultrasonographic tissue characterization that includes structures below the size limits of resolution in equine superficial digital flexor tendons. SAMPLE POPULATION: 2 damaged and 2 structurally normal superficial digital flexor tendons. PROCEDURE: Transverse ultrasonographic images were collected along the tendon long axis. Stability of echo pattern was quantified by means of variation in gray levels of each pixel in contiguous images and expressed as correlation, entropy, and waviness ratios. RESULTS: Normal young and normal old tissues were characterized by high correlation and low entropy and waviness ratios. In necrotic tissue, collapsed intratendinous septa resulted in high correlation, moderate entropy, and high waviness ratios. In early granulation tissue, complete lack of bundle formation resulted in values of zero for correlation and waviness ratios; loose connective tissue matrix resulted in a high entropy ratio. In late granulation tissue, formation of new bundles resulted in a high correlation ratio; swollen intratendinous septa and incomplete organization of connective tissue matrix were reflected in high entropy and waviness ratios. In early fibrotic tissue, rearrangement of tendon bundles resulted in a correlation ratio within reference range and a slight increase in the waviness ratio; an increase in cellularity and lack of fibrillar arrangement led to an increase in the entropy ratio. In late fibrotic and scar tissues, inferior quality of repair with almost complete lack of organization was reflected in low to moderate correlation, low waviness, and high entropy ratios. CONCLUSIONS AND CLINICAL RELEVANCE: Stability of echo patterns accurately reflects homogeneity of tendons in horses.  相似文献   
36.
N. Mathys  S. Brochot  M. Meunier  D. Richard 《CATENA》2003,50(2-4):527-548
Erosion rates measured for 15 years in the small (ranging from 0.13 ha to nearly 1 km2) and steep (30–75%) mountainous marly basins of Draix (South Alps, France) are over 100 tons/ha/year in a badland area devoid of vegetation. In a similar basin, reforested at the end of the 19th century, the sediment yield is considerably reduced (less than 3 tons/ha/year). The analysis of the sediment yield of these torrents reveals the importance of the erosion processes on slopes at the scale of the elementary gully, and the influence of deposition, transport and scouring processes as soon as the channel network of the basin is developed.These processes were modelled by a hydrosedimentologic model developed by Cemagref for flood torrent erosion and called ETC. ETC is an integrated, spatialized and global model, working at the event scale. The rainfall–runoff component and the solid transport component, which involves scouring, deposition and armouring, are well developed. On the other hand, the erosion component is not yet a physically based model as the knowledge on the elementary processes is not enough quantitative. The ETC model was used on a badland basin of 86 ha in area, the Laval, and has shown its ability to simulate both water and sediment flows in mountainous and steep basins. The erosion modelling highlighted the need for a better representation of the slope processes and for more information on the storing of sediments in the channel network. Observations carried out on the influence of the vegetation cover patterns and the links between slopes and channels should be taken into account to improve the model.  相似文献   
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38.
Voluntary approaches have been recently used in the horticultural sector to deal with the introduction and spread of invasive alien plants. In Belgium, the first Code of conduct has been developed within the frame of the AlterIAS project, a LIFE+ “Information & Communication” project aiming at raising the awareness of horticulture professionals and gardeners on the invasive plants issue. The Belgian Code was prepared in consultation with representatives from the ornamental sector, public authorities and the scientific community. The Code was promoted throughout the country with a specific communication campaign entitled “Plant different”. Thanks to communication efforts, a positive dynamic of involvement was observed over time. Surveys were performed to assess the changes of attitudes and the perception of the Code by the target audience of the project. Positive results were achieved for horticulture professionals. However, the Code will require more time to be widely adopted by the ornamental sector in Belgium.  相似文献   
39.
Although it is well accepted that the present Asian H5N1 panzootic is predominantly an animal health problem, the human health implications and the risk of human pandemic have highlighted the need for more information and collaboration in the field of veterinary and human health. H5 and H7 avian influenza (AI) viruses have the unique property of becoming highly pathogenic (HPAI) during circulation in poultry. Therefore, the final objective of poultry vaccination against AI must be eradication of the virus and the disease. Actually, important differences exist in the control of avian and human influenza viruses. Firstly, unlike human vaccines that must be adapted to the circulating strain to provide adequate protection, avian influenza vaccination provides broader protection against HPAI viruses. Secondly, although clinical protection is the primary goal of human vaccines, poultry vaccination must also stop transmission to achieve efficient control of the disease. This paper addresses these differences by reviewing the current and future influenza vaccines and vaccination strategies in birds.  相似文献   
40.
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