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141.
Bphs controls Bordetella pertussis toxin (PTX)-induced vasoactive amine sensitization elicited by histamine (VAASH) and has an established role in autoimmunity. We report that congenic mapping links Bphs to the histamine H1 receptor gene (Hrh1/H1R) and that H1R differs at three amino acid residues in VAASH-susceptible and -resistant mice. Hrh1-/- mice are protected from VAASH, which can be restored by genetic complementation with a susceptible Bphs/Hrh1 allele, and experimental allergic encephalomyelitis and autoimmune orchitis due to immune deviation. Thus, natural alleles of Hrh1 control both the autoimmune T cell and vascular responses regulated by histamine after PTX sensitization.  相似文献   
142.
  1. Taoyuan Algal Reef is a biodiverse coralline algal reef in north-west Taiwan, that is currently threatened by coastal development and industrial waste runoff.
  2. As the reef lies in an exposed area that is frequently disturbed by monsoons, it is difficult to survey using traditional methods. Knowledge of the reef is therefore limited, and has until recently, long been regarded as a barren environment.
  3. However, recent studies have revealed that the reef is inhabited by a diverse array of organisms, particularly at Datan, where a natural gas receiving terminal is planned for construction. Due to challenging environmental conditions, otolith assemblage and soundscape analyses were used to supplement traditional sampling methods including clove oil, netting, and pole-and-line fishing in order to assess the diversity of the fish community at Taoyuan Algal Reef.
  4. Several fish species that had not been recorded by previous surveys were observed. Fish diversity and the average size of commercially targeted species were greatest at Datan G2. Predatory reef fishes such as groupers (Serranidae) and snappers (Lutjanidae), as well as several small endangered scalloped hammerhead sharks Sphyrna lewini were recorded at G2, where otolith assemblage analysis also indicated increased predatory activity. However, fewer individuals and species were recorded from tidal pools across all sites compared to previous surveys, suggesting a loss of biodiversity.
  5. If construction work resumes at Datan, it will be likely to have adverse consequences for the reef itself, the species that inhabit it, and by extension, the local fishermen that rely upon it. Halting additional coastal development, reducing industrial and domestic pollution, as well as improving the management of traditional fisheries is recommended to protect this unique reef ecosystem from further degradation.
  相似文献   
143.
Pham X. Tung 《Euphytica》1992,61(1):73-80
Summary Genetic variance components and heritability were estimated for resistance to bacterial wilt in a population of tetraploid potato with resistance derived from several specific sources. Both additive and non-additive variance components were significant. Their relative magnitudes indicated the importance of non-additive gene action in the genetic control of the resistance. Narrow-sense heritability was relatively low for both disease index and % survival indicating that progress in population development would be slow. Broad-sense heritability was, however, relatively high which promises success of clonal selection in developing clonal resistant cultivars.  相似文献   
144.
Summary Effects of resistance genes and heat tolerance genes on expression of resistance to bacterial wilt caused by Pseudomonas solanacearum were investigated in 30 F1 progenies from parents with different levels of bacterial wilt resistance and heat tolerance. A race 1 and a race 3 isolate of the bacterium were used for inoculation under screenhouse conditions at two locations. Results obtained indicated that with reduction in levels of parental resistance, resistance in the F1 progenies was also reduced. Under hot conditions, a reduced heat tolerance in the genetic background also resulted in lower levels of resistance expression. The effect of heat tolerance tended to diminish at lower temperatures leaving the effect of resistance genes more consistent. There existed a strong interaction between resistance genes and genes for heat tolerance. The nature of resistance to bacterial wilt in potato and implications for breeding for resistance are discussed.Effects of reciprocal crosses on expression of resistance to a race 1 isolate under hot screenhouse conditions, were studied in 5 sets of reciprocal F1 progenies involving different resistant and susceptible parents. The reciprocal differences observed were not significant suggesting absence of cytoplasmic effects on expression of resistance.  相似文献   
145.
Quality tuber planting material is unavailable in the Red River Delta (RRD). The use of True Potato Seed (TPS) was considered as an alternative planting material. During the 1985–86 and 1986–87 seasons, 21 and 40 kilos of open pollinated TPS, respectively, were collected in the southern highlands and distributed to over 40 cooperative groups of farmers in the RRD. Fifty-two hectares (1985-86) and 120 hectares (1986-87) of potatoes were produced from transplants in the two years of on-farm production. Approximately 50% of the farmers were successful in both years. Lack of experience and too wet or too dry growing conditions caused most of the failures. Yields from transplants ranged from 5 to 13 t/ha with 150 to 300 seedling tubers/m2. Seedling tubers can be stored for eight months with low storage losses and when replanted give substantially higher yields than those obtained from locally grown, degenerated seed tubers.  相似文献   
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