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1.
Five popular but iron-inefficient cultivars were crossed with three efficient genotypes and both parents and F1s were evaluated for iron-efficiency in potted calcareous and noncalcareous soil. The iron-efficient genotypes were dark green or green in both noncalcareous and calcareous soils whereas inefficient types were light green to yellow in calcareous soil. The chlorophyll and active iron (Fe2+) concentration of leaves was less in iron-efficient genotypes compared to efficient types in calcareous soil and reduction of both the parameters from noncalcareous to calcareous soil was considerably high in iron-inefficient lines. There was significant correlation between visual scores, chlorophyll and active iron content. There were no differences among F1s for iron chlorosis and they were all iron-inefficient. The frequency of iron-inefficient plants was higher than the efficient plants in all F2 populations. But most of the productive plants came from iron-efficient segregants indicating strong association between iron-efficiency and productivity. Based on the results selection for iron-efficiency in early generations and extensive evaluation for productivity in advanced generations is suggested for developing varieties for cultivation in calcareous soils. 相似文献
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The short-term and long-term effects of two most commonly used brown and black masheri were studied in Swiss mice and Syrian golden hamsters. In short-term studies, both the types of masheri extracts (ME) at 3/4 LD50 dose given ip did not have any effect on either liver or plasma vitamin C levels (both species). However, a decrease in liver vitamin A was observed only in hamsters injected with black ME. Similar effect was not observed in mice injected with both the types of masheri extracts. In long-term studies, when both the types of masheri were fed through diet at 10% level for 20 months, no effect was observed on hepatic or plasma vitamin C levels in mice (both sexes), while an increase in vitamin C levels was observed in black masheri diet fed hamsters. A depletion in liver vitamin A was observed in hamsters fed both the types of masheri. Such an effect was observed only in black masheri diet fed Swiss mice (both sexes) and brown masheri diet fed Swiss females. 相似文献
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The A, B, O, D, Du, C, c, E, e, M, N, S, s, Kell and Duffy antigens were determined on 190 blood samples from Hausas in the north of Nigeria. The highest gene frequencies in the rhesus system were cDe (0.648) and cde (0.176). Su gene frequency was 0.270. The great majority of subjects were Kell negative (98.9%) and Duffy negative (98.8%). As the MNSs group determinants are carried by glycophorins, which are also receptor sites for Plasmodium falciparum, and the Duffy antigen marks the receptor for P. vivax, the present study provides data of interest in the epidemiology and genetics of malaria. 相似文献
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Adsorption of fungal spores on a synthetic polymer - High Density Polyethylene was successfully achieved using different pretreatments. Sonication of beads followed by ferric nitrate treatment or use of 0.1% tributyrin gave adsorption upto 46%. Use of dichloromethane as a solvent for sonication is recommended for its better performance in reuse studies (upto 5 times without much decrease in activity). 100 g of immobilized biocatabyst in a 7 L Fluidized Bed Bioreactor was found to perform better than shaker flask at a much lower power input. 相似文献
8.
Changes in peroxidase activity during pregnancy were examined in CD-1 mice. Peroxidase activity was measured with guaiacol as the substrate in uterine extracts of nonpregnant mice and in uterine, placental, and fetal extracts of pregnant mice on days 9, 12, 14, 16, and 18 of gestation. Uterine peroxidase activity in nonpregnant mice was high, but declined logarithmically to only 0.2% by day 18 of pregnancy. In contrast to this decline, a concomitant 50-fold logarithmic increase in fetal peroxidase activity was observed between day 12 and 18. Activity in placental extracts did not change significantly throughout the gestational period examined. These results suggest that membrane bound peroxidase in mouse uterus and fetus undergoes major shifts during pregnancy. 相似文献
9.
Changes in ovarian follicular kinetics were studied in relation to aging in the Indian skipper frog
Rana cyanophlyctis.Age was determined by skeletochronology, by counting the number of growth rings and lines of arrest of growth from the cross
sections of 4th phalange of 4th toe. For follicular kinetics study oocytes were counted under binocular using 10% of Bouin’s
fixed ovary and they were classified into first growth phase, medium-sized second growth phase, large-sized second growth
phase and atretic follicles.
Analysis of phalangeal cross sections indicated that frogs ranging 14–54 g in body weight and 4.9–8.9 cm in body size showed
1–7 year rings. Frogs that weighed 14–16 g showed 1 year ring, and contained immature ovaries; those with 18 g body weight
had one to two year rings, in which second growth phase oocytes appeared for the first time in the primiparous ovary. Frogs
with 20–54 g body weight showed 2–5 year rings in which ovary contained 5–24% of second growth phase oocytes. Further, body
weight, body size, ovarian weight, number and size of second growth phase oocytes and total number of oocytes showed a significant
(P < 0.05) positive correlation, while, the number of first growth phase and atretic follicles showed a poor correlation with
age.
The results suggest that in nature, the age of
Rana cyanophlyctis
ranges between 1–7 years. Phalangeal growth rings are formed annually. Females attain sexual maturity in 2nd year. Frogs with
2–5 years of age may constitute breeding females. Body weight, body size, ovarian mass, number of second growth phase and
total oocytes, and egg size increase with age up to 5 years. 相似文献
10.
The cytolytic activity of pulmonary CD8+ lymphocytes, induced by infection with a vaccinia virus recombinant expressing the M2 protein of respiratory syncytial virus (RSV), correlates with resistance to RSV infection in mice. 总被引:7,自引:6,他引:1 下载免费PDF全文
A B Kulkarni M Connors C Y Firestone H C Morse rd B R Murphy 《Journal of virology》1993,67(2):1044-1049
Previous studies demonstrated that the pulmonary resistance to respiratory syncytial virus (RSV) challenge induced by immunization with a recombinant vaccinia virus expressing the M2 protein of RSV (vac-M2) was significantly greater 9 days after immunization than at 28 days and was mediated predominantly by CD8+ T cells. In this study, we have extended these findings and sought to determine whether the level of CD8+ cytotoxic T-lymphocyte (CTL) activity measured in vitro correlates with the resistance to RSV challenge in vivo. Three lines of evidence documented an association between the presence of pulmonary CTL activity and resistance to RSV challenge. First, vac-M2 immunization induced pulmonary CD8+ CTL activity and pulmonary resistance to RSV infection in BALB/c (H-2d) mice, whereas significant levels of pulmonary CTL activity and resistance to RSV infection were not seen in BALB.K (H-2k) or BALB.B (H-2b) mice. Second, pulmonary CD8+ CTL activity was not induced by infection with other vaccinia virus-RSV recombinants that did not induce resistance to RSV challenge. Third, the peak of pulmonary CTL activity correlated with the peak of resistance to RSV replication (day 6), with little resistance being observed 45 days after immunization. An accelerated clearance of virus was not observed when mice were challenged with RSV 45 days after immunization with vac-M2. The results indicate that resistance to RSV induced by immunization with vac-M2 is mainly mediated by primary pulmonary CTLs and that this resistance decreases to very low levels within 2 months following immunization. The implications for inclusion of CTL epitopes into RSV vaccines are discussed in the context of these observations. 相似文献