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P.C.Odén 《林业研究》2011,21(1):21-26
Improvement in seed and seedling quality of Acacia auriculiformis after culling phenotypically inferior trees was studied in a 6-year old seed production area (SPA). A 5-ha plantation was identified, of which 2.3 ha was converted into SPA. The initial stocking, 1 612 trees·ha−1, was thinned down to 982 trees·ha−1 based on growth characteristics. The following fruiting season, seeds were collected from 10 randomly selected trees in culled and non-culled stands, and seed physical characters, germination and seedling traits were assessed. Seed weight, seed thickness and percentage germination increased by 32.1%, 4.43% and 22.37%, respectively in the culled stand compared to the non-culled stand. Culling also increased the speed of germination, seedling dry weight and seedling vigor index. Heritability values were high for seed weight (0.974) and seed thickness (0.948) while medium values were observed for percentage germination (0.577) and total dry weight (0.534). Predicted genetic gain was 11.13% and 11.22% for seed weight and percentage germination, respectively. The actual gain was 32.1, 51.9 and 22.9% for seed weight, percentage germination and total dry matter, respectively. In conclusion, SPAs established by culling inferior trees could serve as sources of good quality seeds for reforestation programs until genetically improved seeds are made available.  相似文献   
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Kassim M  Yusoff KM  Ong G  Sekaran S  Yusof MY  Mansor M 《Fitoterapia》2012,83(6):1054-1059
Malaysian Gelam honey has anti-inflammatory and antibacterial properties, a high antioxidant capacity, and free radical-scavenging activity. Lipopolysaccharide (LPS) stimulates immune cells to sequentially release early pro- and anti-inflammatory cytokines and induces the synthesis of several related enzymes. The aim of this study was to investigate the effect of the intravenous injection of honey in rats with LPS-induced endotoxemia. The results showed that after 4h of treatment, honey reduced cytokine (tumor necrosis factor-α, interleukins 1β, and 10) and NO levels and increased heme oxygenase-1 levels. After 24h, a decrease in cytokines and NO and an increase in HO-1 were seen in all groups, whereas a reduction in HMGB1 occurred only in the honey-treated groups. These results support the further examination of honey as a natural compound for the treatment of a wide range of inflammatory diseases.  相似文献   
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Tropical Animal Health and Production - Pneumonic pasteurellosis is an economically important infectious disease in the small ruminant industry which causes sudden death and loss for farmers....  相似文献   
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Implicit economic values of physical attributes of teak logs (girth, length, straightness and soundness) were estimated using hedonic regression. The influence of spatial and temporal variations on teak wood prices was also estimated. The auction prices of teak wood at various Timber Sales Depots of the Forest Department of Kerala State in India during the period 2006–2010 were used for the study. Traders ascribed over 80 % of variation in teak wood prices to girth, straightness and soundness of logs. A reduction in age at felling of teak plantations in forest areas is proposed. The study also underlines the need to continue tree improvement programs and silvicultural operations for the production of high quality teak wood and thereby increase the profitability of teak plantations.  相似文献   
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Purified lipopolysaccharide (LPS) of Pasteurella multocida type 6:B, while toxic at higher doses, was protective at lower dose levels against experimentally-induced pasteurellosis in mice. However, the observed protection was abrogated if such LPS was digested with proteinase K prior to use in immunisation. The O-antigen polysaccharide side-chain (OS) of LPS did not appear to contribute to the observed protection as judged by the fact that immunisation of mice with purified OS or OS-protein conjugates, all of which were non-toxic, failed to confer protection against challenge with homologous virulent organisms. This was despite generation of significant levels of OS-specific antibodies, predominantly either of the IgM or IgG isotypes, in immunised mice.

Résumé

Le lipopolysaccharide purifié (LPS) de Pasteurella multocida type 6:B, toxique à haute dose, est protecteur à faible dose contre la pasteurellose expérimentale de la souris. Cependant, la protection observée est supprimée si le LPS est soumis à l'action de la protéinase K avant immunisation. L'antigène O polysaccharidique du LPS ne semble pas contribuer à la protection observée si l'on en juge par le fait que l'immunisation des souris à l'aide de l'antigène O purifé ou conjugué avec des protéines -- non toxiques -- ne confère pas de protection contre une épreuve virulente homologue. Ceci en dépit de l'apparition de taux significatif d'anticorps anti O principalement soit du type IgM ou IgG chez la souris.  相似文献   

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The outer membrane proteins (OMP) were extracted from the P. haemolytica A2, A7 and A9 to determine their potential as immunogens and their capability for cross-protection. Sixty lambs of approximately 9 months old were divided into four main groups. Animals in Group 1 were vaccinated with 2ml vaccine containing 100microg/ml of the outer membrane proteins of P. haemolytica A2. Animals in Group 2 were similarly vaccinated with the OMPs of P. haemolytica A7 while Group 3 with OMPs of P. haemolytica A9. Animals in Group 4 were unvaccinated control. During the course of the study, serum was collected to evaluate the antibody levels toward each OMP. There appeared to be good immune responses. However, high antibody levels did not necessarily result in good protection of the animals, particularly against cross-infection with P. haemolytica A9 in animals vaccinated with the OMPs of P. haemolytica A2. It seemed that the antibody responses were more specific toward the homologous challenge but generally did not cross-protect against heterologous serotype challenge. However, the OMPs of P. haemolytica A7 produced good in vivo cross-protection and excellent correlations when good antibody responses against all serotypes led to successful reductions of the extent of lung lesions following homologous and heterologous challenge exposures. Thus, the OMPs of P. haemolytica A7 was effective in protecting animals against homologous and heterologous infection by live P. haemolytica A2, A7 and A9.  相似文献   
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