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131.
OBJECTIVE: To assess the impact of a school-based nutrition education intervention aimed at increasing the consumption of fruits and vegetables. DESIGN: The intervention programme increased the provision of fruits and vegetables in schools and provided a range of point-of-purchase marketing materials, newsletters for children and parents, and teacher information. Curriculum materials at age 6-7 and 10-11 years were also developed and utilised. Evaluation was undertaken with groups of younger (aged 6-7 years) and older (aged 10-11 years) children. Methods included 3-day dietary records with interview and cognitive and attitudinal measures at baseline, with follow-up at 9 months, in intervention and control schools. SETTING: The work was undertaken in primary schools in Dundee, Scotland. SUBJECTS: Subjects comprised 511 children in two intervention schools with a further 464 children from two schools acting as controls. RESULTS: Children (n=64) in the intervention schools had an average increase in fruit intake (133+/-1.9 to 183+/-17.0 g day(-1)) that was significantly (P<0.05) greater than the increase (100+/-11.7 to 107+/-14.2 g day(-1)) estimated in children (n=65) in control schools. No other changes in food or nutrient intake were detected. Increases in scores for variables relating to knowledge about fruits and vegetables and subjective norms were also greater in the intervention than in the control group, although taste preferences for fruits and vegetables were unchanged. CONCLUSIONS: It is concluded that a whole school approach to increasing intakes of fruits and vegetables has a modest but significant effect on cognitive and attitudinal variables and on fruit intake.  相似文献   
132.
Rice tungro disease (RTD) is one of the destructive and prevalent diseases in the tropical region. RTD is caused by Rice tungro spherical virus (RTSV) and Rice tungro bacilliform virus. Cultivation of japonica rice (Oryza sativa L. ssp japonica) in tropical Asia has often been restricted because most japonica cultivars are sensitive to short photoperiod, which is characteristic of tropical conditions. Japonica1, a rice variety bred for tropical conditions, is photoperiod-insensitive, has a high yield potential, but is susceptible to RTD and has poor grain quality. To transfer RTD resistance into Japonica1, we made two backcrosses (BC) and 8 three-way crosses (3-WC) among Japonica1 and RTSV-resistant cultivars. Among 8,876 BC1F2 and 3-WCF2 plants, 342 were selected for photoperiod-insensitivity and good grain quality. Photoperiod-insensitive progenies were evaluated for RTSV resistance by a bioassay and marker-assisted selection (MAS), and 22 BC1F7 and 3-WCF7 lines were selected based on the results of an observational yield trial. The results demonstrated that conventional selection for photoperiod-insensitivity and MAS for RTSV resistance can greatly facilitate the development of japonica rice that is suitable for cultivation in tropical Asia.  相似文献   
133.
The aim of this study was to determine the immunoreactivity of normal small bronchial, bronchiolar, respiratory bronchiolar, and interalveolar epithelium using antibodies to six mucins: MUC1, MUC2, MUC4, MUC5AC, MUC5B, and MUC6. The large, gel-forming secreted mucins MUC2, MUC5AC, and MUC5B were widely expressed in the lower respiratory tract. The results of this study demonstrate that these secreted mucins form a gel to cover and protect the mucosal surface in the lower respiratory tract of pigs.  相似文献   
134.
Fasciola hepatica, the liver fluke, is a highly evolved endo-parasite that uses various mechanisms to evade the host immune system. The immunosuppressive capabilities of the parasite's excretory/secretory products have been well demonstrated by previous independent studies. However, the role of the parasite's tegument in the immune responses remains to be investigated. In this study, the effect of the tegument and other fractions of adult F. hepatica (excretory/secretory, liver fluke homogenate and liver fluke homogenate without tegument) in the activation of naïve macrophages in vitro was investigated using an ovine model. In addition, an immunoproteomic approach was used to investigate the characteristics of humoral antibody responses developed in sheep against the tegument fraction. The results indicated significantly increased arginase expression in macrophages incubated with the tegument and excretory/secretory fractions. Two dimensional gel electrophoresis of the tegument demonstrated approximately 100 protein spots, with only four of these spots were highly reactive with the positive serum as determined by 2-DE immunoblotting. These results give a preliminary indication that the liver fluke tegument may play role in avoiding hosts’ protective immune responses against itself.  相似文献   
135.
Avipoxvirus is known to be endemic in New Zealand and it is a cause of ongoing mortalities in the endangered black robin and shore plover populations. There is no information on the strains of avipoxvirus occurring in New Zealand and their likely origin or pathogenicity. This study was designed to identify the phylogenetic relationships of pathogenic avipoxvirus strains infecting introduced, native, and endemic bird species in New Zealand. Avipoxvirus 4b core protein gene was detected in tissue samples from 25/48 birds (52.1%) from 15 different species in New Zealand. Bootstrap analysis of avipoxvirus 4b core protein gene revealed that the New Zealand avipoxvirus isolates comprised of three different subclades. The majority of New Zealand avipoxvirus isolates (74%) belonged to A1 subclade which shared 100% genetic similarity with the fowlpox HPB strain. An isolate from a wood-pigeon (kereru) belonged to subclade A3, displaying 100% sequence homology to albatrosspox virus. An additional group, isolated from two shore plovers and one South Island saddleback, grouped within subclade B1 and presented 99% sequence homology to European PM33/2007 and Hawaiian HAAM 22.10H8 isolates. The results suggest that a variety of New Zealand bird species are susceptible to avipoxvirus infection, that there are more than two distinctive avipoxvirus subclades in New Zealand, and that the most prevalent A1 strain may have been introduced to New Zealand through introduced avian hosts such as passerines or poultry.  相似文献   
136.
137.
We have shown in pigs that oocytes denuded of cumulus cells at 24 h of in vitro maturation culture and subsequently matured for a total of 46 h (DO24 oocytes) have lower cytoplasmic maturity than those matured with cumulus cells for 46 h and then denuded (DO46 oocytes). In the present study, DO24 zona-free oocytes were fused with one (1C) or two (2C) cytoplasmic fragments produced by serial centrifugation ("centri-fusion") of DO46 oocytes (DO24+1C and DO24+2C oocytes, respectively). Groups of (1) DO46 (a control), (2) DO24, (3) DO24+1C and (4) DO24+2C oocytes were partheno-activated by an electrical pulse or fertilized in vitro and subsequently cultured for 6 days. In the fused groups, female pronucleus (FPN) formation rates were higher than that in the DO24 group after parthenogenetic activation (PA); however, the blastocyst rates were intermediate between those of the control and DO24 groups. After in vitro fertilization, the male pronucleus (MPN) formation rates in the fused groups were similar to that in the control group and higher than that in the DO24 group; the normal fertilization rate in the DO24+2C group was higher than that in the DO24 group and similar to that in the control group, resulting in significantly higher blastocyst rates in the DO24+2C and control groups than that in the DO24 group. These results suggest that centri-fusion using ooplasm from fully matured DO46 oocytes can offer a potentially novel approach for restoration of cytoplasmic maturity to oocytes with low developmental ability and subsequent improvement of fertilization and developmental competence.  相似文献   
138.
Culture techniques of antral follicle–like structure (AFLS) derived from cumulus–oocyte complexes (COCs) might provide important insights into follicular development and oocyte maturation. This study was undertaken to investigate the effects of embedding bovine COCs individually (one COC) or in groups (4–5 COCs) in collagen gels on the formation of AFLS and the meiotic status of oocytes. The observations of AFLS formation were performed every second day for 14 days. The AFLS was formed at Day 2 or 4 after the start of culture (Day = 0), irrespective of the culture methods. The mean diameters of AFLS during Days 4–14 using the individual culture method were significantly higher (p < 0.05) than those using the group culture method. However, the AFLS formation rate in the individual culture method was significantly lower compared to that in the group culture method (26.1% vs 62.7%, p < 0.01). Almost all oocytes had undergone the germinal vesicle breakdown stage, irrespective of the culture method or AFLS formation. In conclusion, comparison with the individual culture method revealed that the mean diameters of AFLS in the group culture method were smaller, but more COCs formed AFLS. The group culture method might be useful for evaluating the various hypotheses of follicular formation and interfollicular communication. However, improvement of the group culture system is necessary to prevent the meiotic resumption of oocytes, because the AFLS formation is dependent on the cumulus/granulosa cells surrounding oocytes.  相似文献   
139.
骆驼刺下胚轴组织培养和植株再生研究   总被引:5,自引:0,他引:5  
实验分别以MS、1/SMS为基本培养基,采用不同浓度组合的KT、NAA和蔗糖进行骆刺下胚轴组织培养再生植株过程的研究。结果表明,分化培养基MS+4.0mg/LKT+20g/L糖对诱导下胚轴分化出丛生芽效果最好。  相似文献   
140.
Canine brucellosis is a contagious disease with venereal and oral modes of transmission that produces late abortion in females, epididymides and prostates in males. Diagnosis is difficult because of unstable serum antibody titers that vary from individual to individual as well as between different methods used for their detection. The objective of this work was to evaluate the clinical utility of the immunochromatographic assay (ICA) for serodiagnosis of dogs suspected of having brucellosis, and results were compared with those obtained for hemoculture (HC) and the rapid screening agglutination with 2-mercaptoethanol (2-ME RSAT). The all experimentally infected dogs were positive in ICA, HC and 2-ME RSAT from 5 weeks, 7 weeks, and 3 weeks after infection, respectively. Also, among dogs selected from 10 different breed kennels occurred brucellosis, 24.8%, 39.5% and 39.1% of dogs tested were detected as positive with HC, 2-ME RSAT and ICA, respectively. The kappa value between 2-ME RSAT and ICA was 0.89. The results of this study showed that sensitivity and specificity of the ICA are comparable with those obtained using conventional serological and bacteriological test for brucellosis. In conclusion, the ICA kit provides a handy and accurate tool for the rapid serodiagnosis of canine brucellosis.  相似文献   
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