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991.
XIN JIANG MEIJIE LIAO YONGJIAN LIU TIANXIANG GAO GUANPIN YANG 《Molecular ecology resources》2007,7(3):492-494
Japanese sea bass (Laterolabrax japonicus) inhabits the coast of East Asia and is cage‐cultured currently in China as well. Twenty‐two microsatellite DNA markers were developed and used to type 35 individuals collected along the Chinese coast. The number of alleles per locus ranged from three to 23. The expected heterozygosity ranged from 0.111 to 0.938, while the observed heterozygosity ranged from 0.114 to 0.914. All 22 loci are neutral and independent of each other; two deviated significantly from Hardy–Weinberg equilibrium. These microsatellite DNA markers are moderately informative, which will certainly facilitate the management and exploitation of the genetic resource of L. japonicus. 相似文献
992.
Yong Wook Kim So Young Park In Sun Park Heung Kyu Moon 《Plant biotechnology reports》2007,1(4):237-242
We have tested plantlet formation by somatic embryogenesis using immature seeds of Magnolia obovata. Seed collection date appeared to be critical for embryogenic cell induction. The optimal collection date was 3–4 weeks postanthesis.
The embryogenic cells proliferated, formed somatic embryos, and were subsequently converted into normal plantlets under optimized
culture conditions. Somatic embryo formation from the embryogenic calli was better on sucrose medium than on glucose medium.
The optimum level of sucrose appeared to be 3% with an average of 28 somatic embryos per plate. About 25% of somatic embryos
were converted into normal plantlets in 1/2 MS medium containing gibberellic acid (GA3). During somatic embryo germination, secondary embryogenesis was frequently observed in the lower part of the hypocotyl or
radicle ends of germinating somatic embryos. Finally, about 85% of converted plantlets survived in an artificial soil mixture,
were transferred to a nursery, and have grown normally. 相似文献
993.
Brian M. Polster Rafael Arze Matthew H. Lyttle David G. Nicholls Derek Hudson 《International journal of peptide research and therapeutics》2007,13(1-2):83-91
A step-by-step evaluation of dual-labeled FRET substrates for the protease calpain is reported. The study led to cell permeable
selections, with optimized specificity and effectiveness for the target enzyme, and improved stability to non-specific degrading
enzymes. 相似文献
994.
The present study was conducted to investigate the mRNA expression of the two estrogen receptor (ER) subtypes ERalpha and ERbeta in the brain of Japanese quail embryos. We found expression of both ERalpha and ERbeta mRNA in homogenate of whole head from 6-day-old embryos, and in brain homogenate from 9- and 12-day-old embryos using real-time PCR. In 9- and 12-day-old embryos the ERalpha expression was higher in females than in males. We used in situ hybridization to examine the localization of the ERs in sections from male and female brains on day 9 and day 17 of incubation. On day 9, ERbeta mRNA was detected in the developing medial preoptic nucleus (POM), in the medial part of the bed nucleus of the striae terminalis (BSTm), and in the tuberal region of the hypothalamus. ERalpha signal could not be detected in the POM, the BSTm or the tuberal region in 9-day-old embryos. In 17-day-old embryos, ERbeta was highly expressed in the preoptic area, the nucleus Taeniae of the Amygdala (TnA) and the BSTm. Expression of ERalpha mRNA was detected in parts of the preoptic area and in the telencephalic TnA. No ERalpha expression was found in the BSTm, an area known to be sexually dimorphic in adults. The high embryonic expression of ERbeta in brain areas linked to sexual behavior indicates that ERbeta plays a role in sexual differentiation of the Japanese quail brain. 相似文献
995.
Toshiaki Jo Hiroaki Murakami Satoshi Yamamoto Reiji Masuda Toshifumi Minamoto 《Ecology and evolution》2019,9(3):1135-1146
Environmental DNA (eDNA) analysis has successfully detected organisms in various aquatic environments. However, there is little basic information on eDNA, including the eDNA shedding and degradation processes. This study focused on water temperature and fish biomass and showed that eDNA shedding, degradation, and size distribution varied depending on water temperature and fish biomass. The tank experiments consisted of four temperature levels and three fish biomass levels. The total eDNA and size‐fractioned eDNA from Japanese Jack Mackerels (Trachurus japonicus) were quantified before and after removing the fish. The results showed that the eDNA shedding rate increased at higher water temperature and larger fish biomass, and the eDNA decay rate also increased at higher temperature and fish biomass. In addition, the small‐sized eDNA fractions were proportionally larger at higher temperatures, and these proportions varied among fish biomass. After removing the fish from the tanks, the percentage of eDNA temporally decreased when the eDNA size fraction was >10 µm, while the smaller size fractions increased. These results have the potential to make the use of eDNA analysis more widespread in the future. 相似文献
996.
黑麂食物组成及其季节变化 总被引:3,自引:0,他引:3
2002年12月至2003年11月在浙江省九龙山和古田山自然保护区,分季节采集黑麂 (Muntiacus crinifrons)粪便,采用粪便显微组织学分析方法为主,辅以野外观察,对其食性进行研究。结果表明 :黑麂食物包括29科43种(属)植物。食物中的植物类型包括乔木、灌木、藤本、非禾草类草本和禾草类草本五种类型;灌木是黑麂全年的主要食物,它在食物组成所占的比例为55.4%;三尖杉 (Cephalotaxus fortunei)、光叶菝葜(Smilax glabra)、矩圆叶鼠刺(Itea chinensis var. oblonga)、南五味子(Kadsura longipedunculata)和络石(Trachelospermum jasminoides)为黑麂四季都取食且在食物组成中所占比例较高的植物,分别为 17%、16.5%、9%、8.7%和 4.3%,是黑麂取食的主要食物。方差分析表明 :黑麂的主要食物及其主要种类都存在季节变化。夏秋季节,乔木植物在黑麂食物组成的比例低于冬春季节 ,而藤本植物和草本植物则相反,灌木植物变化较小;黑麂取食的五种主要食物中,其中三尖杉和光叶菝葜季节变化极显著,在冬季,三尖杉和光叶菝葜在食物组成比例中最高,达到 21.7%和 24 .3%;在夏季,它们在食物组成比例中下降到最低点,分别是 11.3%和 11.6%,但相对密度(RD)值仍保持最高序位 ;矩圆叶鼠刺和南五味子变化较平缓 ,基本变化趋势相同:冬春季节比例较高,夏秋季节比例有所下降;络石季节变化不明显;由于黑麂的食物组成中禾草类占的比例很小,说明黑麂更接近嫩食者 相似文献
997.
Guan JZ Maeda T Sugano M Oyama J Higuchi Y Makino N 《Molecular and cellular biochemistry》2007,304(1-2):353-360
Telomeres play a role in cellular aging and they may also contribute to the genetic basis of human aging and longevity. A
gradual loss of the telomeric repeat sequences has been reported in adult tissue specimens. This study determined the percentage
of telomere restriction fragment in various molecular-sized regions in addition to measuring the average telomere length.
Mean telomere restriction fragment (TRF) length was determined by Southern blot analysis using a longer telomeric repeat probe
with higher sensitivity. A significant decrease in longer telomere fragments and a quick increase in the shortest fragments
were observed, especially in male subjects. There was a tendency that the age-adjusted telomere length was longer in females
than that observed in males, while males lose the telomeric sequence faster than females. These data indicated that the percentage
of longer telomeres fragments decreased, while the shortest fragments increased quickly with age. In addition, the longest
telomere fragments decreased and the short fragments increased with a relatively stable frequency with age. There was also
a significant difference in the longest telomere fragment percentage between males and female in their 40s and 50s, whereas
no difference was observed in the mean TRF length. Interestingly, the changing rate of the longest and the shortest range
group of TRF percentage associated with aging seemed quite different between before and after 50-year old with a gender-related
contrast. This contrast implies a drastic change around the age of 50 of unknown factors that affect telomere attrition.
The first two authors equally contributed to this article. 相似文献
998.
Zamin Shaheed Siddiqui 《Acta Physiologiae Plantarum》2007,29(4):303-308
The possible physiological mechanisms behind the allelopathic effects of three concentrations of black pepper (Piper nigrum) whole plants leachings on germination, seedling growth, chlorophyll and chlorophyll supply-orientation (precursors for chlorophyll
biosynthesis) in Vigna mungo var. NIAB were investigated. Fifty and 75% leaching solutions negatively affected germination and seedling growth of V. mungo. Maximum inhibition (58.11%) was recorded in germination at 75% leaching-treated seeds. In addition, seedling growth was
also retarded by the application of leachings. Especially the affect on shoot growth was more evident with the increasing
concentrations compared to root growth. In other experiment 10-day old etiolated seedlings of V. mungo were cultured in growth chamber in one-tenth Hoagland culture solution with or without leaching-concentrations. Leaves were
harvested randomly at 0, 6, 12, 24 and 48-h time interval after treatment. The concentrations of chlorophyll, porphyrin and
its three biosynthetic precursors such as proto porphyrin IX (Proto), Mg-proto porphyrin IX (Mg-Proto), and proto-chlorophyllide
(Pchlide) were determined. Synthesis of chlorophyll and porphyrin was inhibited as the leaching concentrations increased.
The mole percent of Mg-Proto affected by the leachings exhibited the same pattern as that of Pchlide and Proto. The data suggest
that enzymes responsible for the conversion of porphyrin precursors may be the major targets of the leaching causing the significant
decrease in chlorophyll concentration. 相似文献
999.
Olive fruits harvested at cherry and black stages of ripening were processed according the table olive black oxidising processing and sampled after the three main steps: storage in brine, lye treatment and thermal treatment (final product). The results show that the storage in brine contributed positively to the stabilisation of cell wall polysaccharides of olive pulp as the amounts of main polysaccharides practically were maintained in both stages of ripening. The lye treatment introduced degradation of cell walls due to the generalised loss of pectic and hemicellulosic polysaccharides and cellulose, caused by the breakage of ester and hydrogen bonds. On the other hand, the lye treatment introduced shifts in the solubilisation of polysaccharides rendering them more difficult to extract by alkali solutions and enabling their retention in the cellulosic residue, which should contribute positively to cell wall firmness. The thermal treatment introduced degradation of cellulose and increased the solubilisation of polysaccharides with a higher extent in the black olives. This work showed that the differences on the cell wall polysaccharides between stages of ripening are magnified after processing and allowed to conclude that the stage of ripening of olive fruits is determinant for obtaining a final product with adequate texture properties for table olive consumption. 相似文献
1000.
Korénekova B Skalická M Nad P Sály J Korének M 《Biological trace element research》2007,116(1):103-109
We report the effects of cadmium (Cd) and zinc (Zn) on the quality of Japanese quail's eggs. For this study, 60 birds were
divided into 3 groups of 20 subjects each. The animals in group 1 received 4 mg Zn/d, whereas those in group 2 were given
a combination of 4 mg Zn/d and 0.12 mg Cd/d. The quails in group 3 were not given any supplements, acting as controls. The
distribution of Cd and Zn in the eggs, the eggs' mass, and the strength and thickness of the shells were determined after
35 and 58 d of supplementation. Zinc showed a positive effect on the mass of eggs and accumulated mainly in the egg white.
The content of Cd was significantly lower in the egg yolk of birds in group 1 (p<0.001), whereas those in group 2 had decreased eggshell thickness and strength in comparison to groups 1 and 3 (p<0.001). These results suggest that the adverse effects of Cd on the quality parameters of eggs from commercially important
bird species can be, at least in part, counteracted by Zn supplementation. 相似文献