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31.
The mean percentage of cells forming rosettes with 2-aminoethyl isothiouronium bromide-treated sheep erythrocytes (EAETRFC) in the peripheral blood of 10 horn cancer-affected cattle (40.05 +/- 2.91) was significantly low in comparison to the value in unaffected control animals (58.61 +/- 1.68). Immunotherapy with a saline phenol extract of allogeneic tumour tissue resulted in a gradual increase in the mean percentage of EAETRFC on each subsequent week. The increase was statistically significant from the second week onwards and on the sixth week, the percentage of EAETRFC in horn cancer affected cattle (56.80 +/- 1.38) closely approximated the value in unaffected controls. 相似文献
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1. The means, standard errors and coefficients of variation for body weight at fortnightly intervals from day 1 to day 90 of five indigenous strains of White Leghorn were estimated. 2. The differences between the strain and body weight were significant at all ages while the differences between sex were significant from day 45. 3. Phenotypic correlations between body weight at day 1 with that of day 30, 60 and 90 were 0-237, -0-007 and -0.07. 4. The heritability by paternal half-sib method ranged from 0-32 to 0-54 for body weights from day 1 to day 90. 相似文献
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To improve the breeding of chickpea varieties with resistance to Fusarium wilt, an attempt was made to analyse the biochemical basis of disease resistance by measuring levels of chitinase, β-1,3-glucanase, protease and proteinase inhibitor activities in dry and soaked seeds and in root and shoot tissues of wilt-resistant and wilt-susceptible cultivars. Marginal variation was observed in the levels of the candidate proteins in dry or soaked seeds. Chitinase activity was higher in roots than in shoots or cotyledons. No proteinase inhibitor activity was detected in root and shoot tissue of any of the cultivars. When the levels of these proteins were analysed in resistant (Vijay) and susceptible (JG-62) cultivars during development of wilt by growing plants in soil infested with F. oxysporum f.sp. ciceri , race 1, both cultivars showed induction of chitinase activity in the roots. However, the induced activity in JG-62 (3.82 U g−1 ) was equivalent to the constitutive level in Vijay (3.90 U g−1 ) and much lower than that induced in Vijay (5.18 U g−1 ). Induction of protease activity was observed only in root extracts of Vijay when challenged by the pathogen. The root extract of Vijay showed in vitro antifungal activity in a plate assay. Simultaneous induction of proteolytic and chitinolytic activities specifically in the resistant cultivar was correlated with antifungal properties of root extracts effective in conferring resistance. 相似文献