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11.
Shotaro NISHIMURA Hitomi SHIMODA Ichiro OSHIMA Yoshitaka ONO Kaoru OKANO Akira ISHIBASHI Shoji TABATA Hisao IWAMOTO 《Animal Science Journal》2005,76(6):575-579
Alpha‐melanocyte stimulating hormone (α‐MSH) is one of the main regulators for melanocytes, and the adenohypophysis is one of the major tissues for the synthesis of this hormone. The Silky fowl is a characteristic breed of chicken with hyperpigmentation throughout the body. The involvement of the adenohypophysis in the hyperpigmentation of this breed is not known. In the present study, the proportion of melanocyte stimulating hormone‐immunopositive cells (MSH cells) in the adenohypophysis was immunocytochemically compared between Silky, Red Cornish × New Hampshire (RN) crossbred and Japanese bantam cockerels at 15 weeks of age. After the body and gland were weighed, the adenohypophyseal cells were enzymatically dispersed and immunostained for α‐MSH, and the immunopositive MSH cells were counted. The weights of the body and adenohypophysis were heaviest in the RN crossbred, followed by the Silky and lightest in the bantam cockerels. In contrast, the ratio between adenohypophysis and bodyweight was much larger in the Silky and the bantam than in the RN crossbreed (P < 0.05). The population of MSH cells in the adenohypophysis was larger in the Silky (14.3%) than in the RN crossbreed (8.0%) and the bantam (8.1%) cockerels (P < 0.05). From these results, it was concluded that prepubertal Silky cockerel have numerous MSH cells in the adenohypophysis suggesting a relationship to hyperpigmentation. 相似文献
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13.
Yoshitaka Oishi 《Biological conservation》2009,142(12):2854-2861
Drought-sensitive bryophytes are especially vulnerable to edge effects caused by forest fragmentation. Because of increased forest fragmentation, these bryophyte species are declining and are in need of conservation. Considering that a field survey including all bryophyte species is very time consuming, methods that make identification less difficult should be tested for their usefulness in conservation. This paper describes an alternative survey method that utilizes the correlation between bryophyte life-forms and microclimates for evaluating drought-sensitive bryophytes. This survey method was examined using epiphytic bryophyte flora on tree trunks in 27 fragmented forests of Kyoto city, in the western part of Japan. The usefulness of life-forms for this evaluation was discussed based on the correlation of life-forms with species richness and microclimates. The results indicated that, while life-from richness was considered to reflect the heterogeneity of moisture availability and light intensity in bryophyte habitats, a certain life-form category (for example, fans and dendroids) seemed to correlate with drought sensitivity of bryophytes. Considering this correlation, an alternative survey method was proposed that utilizes the richness of hygrophilous life-forms. This survey method seems to be more cost-effective than a traditional all-species survey, and provides an important step toward the conservation of drought-sensitive species. 相似文献
14.
Mohammad Ashik Iqbal Khan Kihachi Ueno Sakae Horimoto Fuminori Komai Kinji Tanaka Yoshitaka Ono 《Biology and Fertility of Soils》2009,45(3):305-313
The aims of this study were to monitor the changes in physicochemical, including spectroscopic, and biological characteristics
during composting of green tea waste–rice bran compost (GRC) and to define parameters suitable for evaluating the stability
of GRC. Compost pile temperature reflected the initiation and stabilization of the composting process. The pH, electrical
conductivity, NO3
−-N content, and carbon-to-nitrogen ratio were measured as chemical properties of the compost. The color (CIELAB variables),
humification index (the absorption ratio Q
4/6 = A
472 / A
664 of 0.5 M NaOH extracts), absorption at 665 nm of acetone extracts, and Fourier-transform infrared (FT-IR) spectra were measured
to evaluate the organic matter transformation; germination of komatsuna or tomato seeds was measured to assess the potential
phytotoxicity of composting materials during composting. No single parameter was capable of giving substantial information
on the composting process, the nutrient balance, phytotoxicity, and organic matter decomposition. The FT-IR spectra at 3,300,
2,930, 2,852, and 1,065 cm−1 provided information on the molecular transformation of GRC during composting and they decreased over the composting. Most
of the assayed parameters showed no further change after about 90 days of composting suggesting that GRC can be used for agricultural
purposes after this period. 相似文献
15.
The effect of ammonium nitrogen concentration in soil solution on the establishment of rice plants was examined. The increase of the concentration decreased the percentage of establishment of seeds sown in submerged soil, although most of seeds sown on submerged soil became established. Therefore, the increase of ammonium nitrogen concentration in soil solution may impair the establishment of seeds sown in submerged soil, which would occur presumably because the increase delays the spear growth and emergence without the decline of soil redox potential. Several seed lots with various nitrogen contents were obtained from rice plants grown under various conditions. The percentage of establishment of low-nitrogen seeds sown in submerged soil was much lower than that of high-nitrogen seeds, especially in soils whose solution contained a large amount of ammonium nitrogen. However, the difference in the percentage of establishment between high- and low-nitrogen seeds sown on submerged soil was much smaller. Therefore, the increase of seed nitrogen content may improve the percentage of establishment of seeds sown in submerged soil, presumably because the increase accelerates the spear growth and emergence. Consequently, for direct sowing in submerged soil, ammonium nitrogen concentration in soil solution should remain low because ammonium nitrogen exerts an adverse effect on seedling establishment, and vigorous seeds with a high nitrogen content should be sown because seed nitrogen exerts a beneficial effect on seedling establishment. 相似文献
16.
17.
Fish‐processing wastes as an alternative diet for culturing the minute rotifer Proales similis de Beauchamp 下载免费PDF全文
Robert Nesta Kagali Eric Ochieng Ogello Yoshitaka Sakakura Atsushi Hagiwara 《Aquaculture Research》2018,49(7):2477-2485
We evaluated the suitability of fish waste diet (FWD) for culturing the minute rotifer Proales similis through the observation of their population growth and particle size selective feeding. A total of five treatments either with Nannochloropsis oculata or FWD (0.75 and 0.50 g/L) or the combination of N. oculata and FWD were set up in triplicates. P. similis were cultured in diluted natural seawater (8 g/L salinity) and 26 ± 1°C with the diet treatments being applied randomly. We daily monitored the rotifer density, the number of bacteria and the water quality in all the cultures. The population density of P. similis increased exponentially in all treatments, while the mean growth in FWD 0.75 g/L was significantly higher (p < .05) than that in the control. Addition of N. oculata to FWD resulted to lowered P. similis population growth. Bacterial colony count was high in FWD and introduction of P. similis to the diet decreased their density. The estimated bacteria ingestion rates were generally in the range of 6.03 × 102–1.24 × 104 bacteria/rotifer/hr and there was a positive linear relationship between bacterivory and rotifer population growth. We also observed a shift in the particle size distribution with a reduction in the frequency and concentration of small‐sized particles (<2.5 μm) at day 6. These results accentuate the potential of fish‐processing waste as diet for culturing P. similis which feeds on bacteria and small particles (≤2.5 μm) that are by‐products of degradation of this diet. 相似文献
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19.
Yoshitaka Hara 《Plant Production Science》2017,20(4):406-411
Seed coating with molybdenum compounds improves seedling establishment for rice, wheat, barley, and soybean when such seeds were sown under flooded conditions. Tungsten belongs to the same chemical group as molybdenum in the periodic table, and similar to molybdenum, inhibits the generation of sulfide ions. Here, the effects of tungsten and molybdenum containing seed coatings on seedling establishment under flooded conditions were compared using rice, wheat, barley, and soybean. In rice, the effects of tungsten compounds on seedling establishment varied. Tungsten trioxide had little effect but tungstic acid and ammonium phosphotungstate significantly improved seedling establishment when the amounts were at least .1–.2 mol W kg?1. Although the effect of tungsten coating varied depending on the compound used, ammonium phosphotungstate, along with other tungsten compounds, improved seedling establishment in a manner comparable with that of molybdenum compounds. For wheat and barley, ammonium phosphotungstate treatment resulted in a significant increase in establishment that was only slightly less than the results observed using molybdenum compounds. Tungstic acid and ammonium phosphotungstate treatments improved soybean establishment in a significant manner that was comparable with those of molybdenum compounds. Collectively, these results suggest that tungsten compounds, as well as molybdenum compounds, improve seedling establishment under flooded conditions. 相似文献
20.
Wei-Qin Wang Tomohide Natsuaki Yoshitaka Kosaka Seiichi Okuda 《Journal of General Plant Pathology》2006,72(1):52-56
To identify possible sites of viral attenuation, the complete nucleotide sequences of two isolates of Zucchini yellow mosaic virus (ZYMV) were determined; a severe isolate Z5-1 and an attenuated isolate from Z5-1 (designated ZYMV-2002). The viral genome
of both isolates consisted of 9593 nucleotides in size and contained an open reading frame encoding a single polyprotein of
3080 amino acids. Comparison of the nucleotide sequences for Z5-1 and ZYMV-2002 revealed 14 nucleotide mutations, resulting
in seven amino acid substitutions with four in the HC-Pro region, two in the CI region, and one in the NIb region. These results
provide a genetic basis for future manipulation of the ZYMV reverse genetics system.
The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession numbers AB188115
and AB188116 相似文献