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151.
Boniface Baboreka KAYANG Miho INOUE-MURAYAMA Hideaki TAKAHASHI Mitsuru MINEZAWA Masaoki TSUDZUKI Makoto MIZUTANI Shin'ichi ITO 《Animal Science Journal》2003,74(4):255-259
Twenty‐eight original chicken microsatellite markers were isolated and characterized to determine their utility as cross‐reactive markers for comparative genetic mapping in the order Galliformes. Primer pairs were typed in 12 unrelated chickens and also tested on Japanese quail and helmeted guinea fowl deoxyribonucleic acid (DNA). Polymorphism was observed in 23 (82.1%) of the markers and the average number of alleles per locus was 2.9 while the mean heterozygosity was 0.19. Eleven (39.3%) of the chicken markers cross‐reacted with Japanese quail DNA and 2 (7.1%) with helmeted guinea fowl DNA. The cross‐reactive markers described would serve as useful resources for comparative genetic mapping in poultry species belonging to the order Galliformes. 相似文献
152.
Successful interspecific hybridization between Cucumis sativus L. and C. hystrix Chakr. 总被引:13,自引:0,他引:13
Jin-feng Chen Jack E. Staub Yosuke Tashiro Shiro Isshiki Sadami Miyazaki 《Euphytica》1997,96(3):413-419
Interspecific F1 hybrids were obtained from a cross between Cucumis sativus L. (2n = 2x = 14) and C. hystrix Chakr. (2n = 2x = 24). Controlled
crossing resulted in fruit containing embryos which were excised and rescued on a Murashige and Skoog solid medium. A total
of 59 vigorous plants were obtained from a fruit containing 159 embryos (37.3% regeneration rate). Hybrid plants were morphologically
uniform. The multiple branching habit, densely brown hairs (especially on corolla and pistil), orange-yellow collora, and
ovate fruit of F1 hybrid plants were similar to that of the C. hystrix paternal parent. While appearance of the first pistillate flower was
more similar to that of C. sativus maternal parent than to C. hystrix, staminate flower appearance was mid-parent in occurence.
The diameter and internode length of stem, shape and size of leaves and flowers were intermediate when compared to the parents.
An elongated green, trilobate style/stigma which was not apparent in either parent was observed in staminate flowers of F1 plants. Similarly, the style/stigma of pistillate flower of F1 plants were longger when compared to their parents. The brown pubescence observed on pistillate flowers of the F1 and C. hystrix was not observed on the C. sativus parent. The somatic chromosome number of F1 plants was 19. Two morphologically distinct groups of chromosomes were observed in the F1 hybrid; 7 relatively large chromosomes characteristic of C. sativus, and 12 smaller chromosomes characteristic of C. hystrix.
Analysis of malate dehydrogenase isozyme banding patterns provided additional comfirmation of hybridity. Reciprocal crossing
of F1 plants to either parent and self-crossing indicated that the hybrids were male and female sterile.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
153.
154.
155.
A novel black tea pigment and two new oxidation products of epigallocatechin-3-O-gallate 总被引:3,自引:0,他引:3
During tea fermentation, oxidation-reduction dismutation of a number of quinone metabolites of tea catechins yields numerous minor products, which make it difficult to separate and purify black tea polyphenols. In this study, epigallocatechin-3-O-gallate was enzymatically oxidized and then the unstable quinone metabolites in the oxidation mixture were hydrogenated with 2-mercaptoethanol to reduce production of inseparable minor dismutation products. As a result, three new oxidation products including a new black tea pigment were isolated, and their structures were determined based on chemical and spectroscopic data. Dehydrotheasinensin AQ is a new reddish-orange pigment with a 1,2-diketone structure, and its presence in commercial black tea was confirmed. In addition, a new quinone dimer with a complex caged structure and a trimer of epigallocatechin-3-O-gallate were also isolated and their production mechanisms are proposed. The presence of this trimer suggested participation of galloyl quinones in production of minor polyphenols in black tea. 相似文献
156.
Analysis of the nitrogen nutrition of soybean plants with deep placement of coated urea and lime nitrogen 总被引:1,自引:0,他引:1
157.
Yosuke Kuroda Hathairat Urairong Yo-Ichiro Sato 《Genetic Resources and Crop Evolution》2005,52(2):151-160
Asian common wild rice (Oryza rufipogon) is a polycarpic perennial plant with a mixed inbreeder/outbreeder strategy. Seeds and clones are both reproductive components of the population. However, when collected in the flowering stage, the two differ substantially as to whether they have experienced natural selection directly or not. This study is aimed at evaluating mechanisms for the survival of a population by comparing genetic structure among subpopulations that are classified in terms of: (1) reproductive systems (clones or seeds); and also (2) location (fringe or inside). First, the genotypes determined at seven SSR (Simple Sequence Repeat) loci showed that parameters of observed heterozygosity (HO) and outcrossing rate (t) were clearly higher in clones (HO = 0.609, t = 82.4%) than in seeds (HO = 0.346, t = 35.5%), although the two had approximately the same values for the number of alleles (A) and expected heterozygosity (HE)(A = 4.43 in both clones and seeds, HE = 0.709, 0.692 in clones and seeds, respectively). This result indicates that the individuals showing heterosis, with high numbers of heterozygous loci and outcrossing rates, are more likely to survive in the natural habitat. Secondly, parameters of observed heterozygosity and outcrossing rates were lower for seeds from the fringe area (HO = 0.238, t = 24.6%) compared to seeds from the inside area (HO = 0.443, t = 60.7%), although values were similar in clones of both the fringe and inside areas. This result suggests that the edge effect might be due mainly to the restriction of wind strength in fringe area of the forested swamp. 相似文献
158.
Keita Ishikawa Radostina Doneva Evgeniy G. Raichev Stanislava Peeva Valentin D. Doichev Yosuke Amaike Yoshinori Nishita Yayoi Kaneko Ryuichi Masuda 《Animal Science Journal》2021,92(1):e13630
The East Balkan Swine (EBS) is the only indigenous pig breed in Bulgaria. We analyzed the mitochondrial DNA (mtDNA) control region and 21 microsatellite loci for 198 individuals from 11 farms in Bulgaria. Obtained 11 mtDNA haplotypes including three novel ones were grouped to two major clades, European clade E1 (146/198 individuals, 73.7%) and Asian clade A (52/198, 26.3%). The mixture of the two clades may have resulted from historical crossbreeding between the European and Asian pig breeds. Clade A was frequent in southeastern Bulgaria (Burgas Province), but less frequent or absent in northeastern Bulgaria (Varna and Shumen Provinces). The distribution of Europe- and Asia-specific haplotypes relative to EBS farm locations could be attributed to regional differences of breeding systems (e.g., crossbreeding with imported commercial pigs). A microsatellite analysis showed high heterozygosities for all the EBS farms, and negative inbreeding coefficients presumably due to crossing with commercial pigs or wild boars and/or efforts to reduce inbreeding by farmers. Bayesian clustering analyses showed that all farm populations are genetically well distinguishable from one another. Although diversity has been maintained by the efforts of farmers and a breeding association, the effective population size remains small, and conservation efforts should be continued. 相似文献
159.
Kimie NIIMI Eiki TAKAHASHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(5):784
Wasting marmoset syndrome (WMS) is a serious disease in captive common marmoset (Callithrix jacchus) colonies. Because of the high mortality rates, elucidation of the underlying mechanisms is essential. In this study, we compared the histopathology, the number of each epithelial cell in the jejunum and colon, and the expression patterns of some molecular markers between healthy and WMS-affected marmosets. Atrophy of villi in the jejunum and mononuclear cell infiltration in the lamina propria were observed in the intestinal tract of WMS-affected marmosets. Although the numbers of transient amplifying cells and tuft cells were increased, the number of goblet cells was obviously decreased in the jejunum and colon of WMS-affected marmosets compared to healthy marmosets. In addition, the number of enterocytes in the jejunum was decreased in WMS animals. There was no apparent difference in the numbers of stem cells, enteroendocrine cells, or Paneth cells. The expression of β-catenin and Tcf7l2 was increased in WMS, and the co-existence of β-catenin and Tcf7l2/Cyclin D1 was observed around the crypts in WMS-affected marmosets. These findings suggest that cell proliferation continues, but cell differentiation is halted in the intestinal tract due to the enhanced β-catenin/Tcf7l2/Cyclin D1signaling pathway in WMS, which results in malfunction of the villus and mucosa. 相似文献
160.
ABSTRACT: Heating temperatures of 30–40°C and KCl concentrations of 0.1–0.5 M altered the denaturation mode of carp myofibrils. In 0.1 M KCl medium, heating temperature affected the denaturation of rod more significantly than of subfragment-1 (S-1), and a slow decrease in solubility at 30°C was accompanied by a slow denaturation of rod. KCl concentration at heating altered the denaturation mode differently at 30°C and 40°C. Increased KCl concentrations for heating reduced the rod denaturation rate at 40°C, but it was increased at 30°C. At concentrations above 0.3*Τ*M KCl, the denaturation rate for rod became identical to that for S-1 at both temperatures. Upon heating of chymotryptic digest of myofibrils, S-1 denaturation was similarly detected as in intact myofibrils, whereas practically no rod denaturation was detected. Thus, it was concluded that myosin structure connecting S-1 and rod has an important role in the denaturation process. 相似文献