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31.
The shallot is considered an important genetic resource for Allium breeding programs because, compared to the bulb onion, the shallot contains higher levels of several functional chemical compounds. However, there may be differences in content, composition and beneficial activity among shallot landraces. This study was carried out to characterize the differences in phenolic, quercetin, sugar, S-alk(en)yl-l-cystein sulfoxide (ACSO), and saponin contents and antioxidant capacities of a shallot germplasm including 31 strains derived from different regions of Vietnam and six other countries. A wide variation was observed in the quantitative analyses of the chemical contents. Shallots with high contents of polyphenols, saponins, and quercetins were found in the south of Vietnam and other low-latitude countries. Meanwhile, those possessing fairly high ACSO and sugar contents were observed in the north of Vietnam. Qualitative analysis of saponins via thin layer chromatography did not show clear variation among shallot strains, but polymorphism was observed between the shallot and other Allium species, such as A. roylei. The principal component analysis could clearly discriminate shallot strains by their geographical origins. All shallot strains showed potent antioxidant activities in a DPPH assay. The highest antioxidant capacity was in the strains possessing relatively high contents of polyphenol, quercetin, and saponin. Significant correlations were found between antioxidant capacity (IC 50 ?1 ) and four groups of chemical compounds (polyphenols, quercetins, saponins, and ACSOs) (r = 0.40–0.59). A strong correlation was observed between IC 50 ?1 and quercetin contents (r = 0.59, p < 0.01). The six Fusarium-inoculated shallot strains seemed to be adequately resistant against disease, and the levels of resistance may be related to the saponin content in the bulb tissues.  相似文献   
32.
The inheritance of organelle DNA was investigated using PCR–RFLP markers in reciprocal cross combinations of inter-subgeneric azalea hybrids between evergreen azaleas (Rhododendron nakaharai and its hybrids) and fragrant deciduous azaleas (R. arborescens and R. viscosum) for the purpose of breeding fragrant evergreen azaleas. The hybrid progenies included green leaf, pale green leaf, variegated leaf and albino seedlings. Most viable green leaf seedlings had inherited ptDNA from the deciduous parent and non-viable albino and pale green leaf seedlings had inherited ptDNA from the evergreen parent. On the other hand, variegated leaf seedlings had chimerically inherited ptDNA from both parents. Their green leaf segments had ptDNA from the deciduous parent, and the pale green and white segments had biparental or maternal ptDNA depending on the progeny. In this study, we obtained interesting inter-subgeneric azalea hybrid progenies that had chimerically inherited organelle DNA and had different colored leaf segments corresponding to the composition of ptDNA from each parent. These results suggest that variegated leaf progenies with chimeric ptDNA from both parents can be subsistent, whereas albino seedlings resulting from plastome–genome incompatibility between the plastid genome from evergreen azalea and the nuclear genome from deciduous azalea are non-viable.  相似文献   
33.
Sharka disease, caused by plum pox virus (PPV), is the most serious viral disease of stone fruit trees. Among the eight known strains of the virus, PPV-D is the most important due to its recent global spread. Although enzyme-linked immunosorbent assay (ELISA) is the most common approach for diagnosing sharka, it involves time-consuming steps and requires expensive equipment and trained technicians. In this study, an on-site PPV detection kit based on immunochromatography was developed using polyclonal antibodies against the coat protein (CP) of a PPV-D isolate. The immunochromatographic (IC) assay kit was as sensitive as a commercial ELISA system for detecting Japanese PPV-D isolates. Moreover, it was easy to use (a one-step procedure), and results could be obtained on-site within 15 min without special laboratory equipment. The IC assay kit detected the virus from every aerial part of symptomatic Japanese apricot trees. In a detailed study of viral localization in leaves, the most suitable plant parts for use in the IC assay were symptomatic mesophyll tissues and the region from the petiole to the main vein. A positive reaction was also observed using the CP of other major (PPV-M and PPV-Rec) and minor (PPV-EA, PPV-W, and PPV-T) strains.  相似文献   
34.
Paddy and Water Environment - This research focused on two large-scale paddy irrigation schemes of Doho (1000&nbsp;ha) and Lwoba (700&nbsp;ha) in Uganda for a comparative analysis of major...  相似文献   
35.
A cDNA clone encoding a prohibitin-like protein (Toprh) was isolated from a piroplasm cDNA library of Theileria orientalis and its nucleotide sequence was determined. An open reading frame, encoding a polypeptide of 278 amino acid residues, was found in Toprh cDNA sequence. An intron of 89 bp was identified when this cDNA clone was compared with the Toprh gene in the genome of T. orientalis. The deduced amino acid sequence of Toprh shares 93.8, 93.1 and 69.1% identities with the prohibitins of T. parva (from chromosome 1), T. annulata (from chromosome 1), and Plasmodium falciparum, (from chromosome 10), respectively. By Western blot analysis, Toprh was found to be expressed in the piroplasm stage of the parasites.  相似文献   
36.
Thoracic radiographs of fifteen beagles with mild-to-moderate obesity revealed that oppression of the thoracic cavity increased with increasing degree of obesity. Oppression of the thoracic cavity was evaluated based on the length, depth, width and area of the thoracic cavity. To obtain thoracic radiographs at the terminal inspiration and expiration phases, thoracic fluororadiographs were recorded with a digital video camera. Bodyweight and the depth of the back fat layer at the seventh lumbar vertebra (DB, measured by ultrasonography) were used as indicators of the degree of obesity. The length of the thoracic cavity tended to become shorter and the depth and width of the thoracic cavity tended to increase as bodyweight increased and as DB increased. On the other hand, the area of the thoracic cavity was not clearly related to bodyweight or DB. These results suggest that oppression of the thoracic cavity due to the cranial shift of the diaphragm is compensated for by increases in the depth and width of the thoracic cavity in beagles with mild-to-moderate obesity.  相似文献   
37.
Triamcinolone acetonide (TAC), a synthetic glucocorticoid, induces cleft palate resulting from poor development of palatal shelves in mice. However, TAC has no effect on medial edge epithelial cells (MEE cells) in secondary palatal shelves. In the present study, we examined the relationship between the pathogenesis of cleft palate and the effects on MEE cells and palatal mesenchymal cells in rat embryos/fetuses exposed to TAC. Pregnant Wistar Hannover rats were given TAC intramuscularly at 0.5 mg/kg at gestation days (Day) 12, 13, and 14, then embryos/fetuses were harvested on Days 14.5, 15, 16 and 20. The effects of TAC were as follows; an inhibition of palatal mesenchymal cell proliferation on Day 14.5, a decrease in the density of palatal mesenchymal cells and MEE cells, and expression of epidermal growth factor (EGF) receptors in MEE cells on Day 15, and stratified squamous differentiation of MEE cells with expression of cytokeratin and EGF receptors on Day 16. These findings indicated that TAC inhibited the proliferation of mesenchymal cells and affected the differentiation of MEE cells into stratified squamous epithelia in the palatal shelves of rat embryos. However, these stratified squamous MEE cells partially fused with each other. Thus, we suspected that a major contributing factor to the formation of TAC-induced cleft palate might not be the altered differentiation of MEE cells, but the inhibition of mesenchymal cell proliferation.  相似文献   
38.
Randomly selected serum samples from 150 dogs from Yamaguchi and neighbouring prefectures were subjected to the indirect immunofluorescent assay to detect antibodies against Ehrlichia canis, Ehrlichia chaffeensis, Ehrlichia muris and Ehrlichia from Ixodes ovatus. A total of 30 out of the 150 serum samples reacted with at least one of the antigens at a titer of 1:20 or more. Considerable cross-reactivity was seen and most samples reacted with at least two different antigens. Fifteen (10.0%) dogs had higher titers to E. canis than any of the other antigens. Four (2.7%) dogs had higher titers to Ehrlichia from Ixodes ovatus and one (0.6%) dog had higher titers to E. muris compared to the other antigens. The findings suggest that these five dogs may be infected with the domestic Ehrlichia of Japan. The remaining ten dogs had similar high titers to two or more of the antigens. This is the first serological evidence obtained of canine infection with the domestic Ehrlichia of Japan.  相似文献   
39.
In order to investigate the toxic effects of 6-mercaptopurine (6-MP) on placental development, we examined sequential morphology in the placentas from rats exposed to 6-MP. 6-MP was intraperitoneally administered at 60 mg/kg during gestation days (GDs) 11 to 12, and the placentas were sampled on GD 13, 15 or 21. In the 6-MP-treated group, maternal body weight suppression, increased death embryo/fetus ratio and some malformations were observed. The placenta weights were decreased on GDs 15 and 21. Macroscopically, placentas on GD 21 were small, brittle and thin with a white peripheral rim. Histopathologically, in the labyrinth zone, 6-MP treatment mainly evoked decreased mitosis on GDs 13 and 15, increased apoptotic cell on GDs 13, 15 and 21 and thinning on GDs 15 and 21. In the basal zone, 6-MP evoked decreased mitosis on GDs 13, and PAS-positive material in the spongiotrophoblasts was still detected on GD 15. Thickening of the basal zone was observed with cytolysis of glycogen cells, apoptosis and an increased number of composed cells on GD 21. In conclusion, 6-MP administration in pregnant rats induced growth arrest of the labyrinth zone and developmental delay in the basal zone, leading to small placentas. The fetotoxicity of 6-MP may be responsible for its direct anti-proliferative effects and resulting placental dysfunction.  相似文献   
40.
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