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71.
The ears of paddy rice at boot stage, that is, just before heading, are being imbeded in the boot leaves' sheaths and are known to produce much guttation li:juid from their spikelets. 相似文献
72.
Fatty acid composition of the crude lipid fraction of peat was investigated using several typical peat profiles in Japan. Fatty acid composition varied with the peat layers accumulated in a peat profile since 32,000 years BP. Deposition of long-range transported volcanic ash tephras also affected the composition remarkably due to the acceleration of decomposition. Fatty acid composition differed among high moor, transitional moor, and low moor peat profiles sampled in several locations in Hokkaido, Japan. The difference in the plants involved in the formation of peat was considered to be a very important factor determining the fatty acid composition. For example, arachidic acid was considered to be a good indicator for the presence of reed, while the percentage of stearic acid tended to be high in the high moor peat profiles dominated by sphagnum. As the fatty acids with a longer chain length were more stable than those with a shorter chain length, the percentage of longer fatty acids (C24 and C26) tended to increase and that of shorter fatty acids (CI4 and CI6) to decrease in the lower peat profiles. The drying of peatland also exerted a similar effect on the fatty acid composition. 相似文献
73.
In order to verify the precursory role of methionine (Met) in the biosynthesis of the mugineic acid family of phytosiderophores (MAs), feeding experiments of 14C-Iabeled compounds to barley (Hordeum vulgare L. cv. Minorimugi) roots grown hydroponically were conducted. When both l4C-Glucose (Glc) and unlabeled Met were fed to segmented roots, 14C was incorporated into Met and MAs in the roots. Molar-radioactivity of Met was higher than that of the amino-butanoic-acid unit in MAs in the roots. When l4C-Glc and unlabeled homoserine (Hse) were fed to decapitated roots, l4C was incorporated into Met but not into Hse. Therefore, it was considered that Hse might not be a major precursor of MAs. In addition, 14C was incorporated into Met and MAs in the roots when both 14C-glycerol (Gol) and unlabeled Met were fed to segmented roots. It is suggested that MAs may be synthesized from Glc via Met, bypassing Hse, and that the MAs biosynthesis may involve an unknown pathway associated with Gol and leading to Met. 相似文献
74.
Takeshi Yokono Yutaka Tamai Tomonori Azuma Yoh Sakuma Kiyoshi Miura Yasuo Kojima Masahide Sunagawa Masatake Ohmasa 《Journal of Wood Science》2000,46(6):480-484
The purpose of this research was to analyze the karyotype of the interspecific fusants of twoPleurotus species. Auxotrophic mutants derived from the cultivated strain ofP. ostreatus andP. cornucopiae were used. Protoplasts were fused electrically, and the fusants were selected under auxotrophic complementation. Esterase isozyme analysis showed that several fusants had isozyme bands originating from both parental strains, and others had unilateral isozyme bands. The fusant that had expressed isozyme bands of both parental strains showed chromosomal DNA bands of both of the parental strains in pulsedfield gel electrophoresis analysis. Despite the above results, the chromosomal composition of the fusants obtained by the pulsed-field gel electrophoresis did not exhibit all of the bands of both fusion parents. 相似文献
75.
Doolyi Kim Yutaka Tamai Tomonori Azuma Akira Harada Akira Ando Yoh Sakuma Kiyoshi Miura 《Journal of Wood Science》2000,46(6):466-469
The karyotype ofFlammulina velutipes (Curt.: Fr.) Sing. was analyzed electrophoretically using contourclamped homogeneous electric field gel electrophoresis and hybridization with DNA probes. The chromosomal DNA from the monokaryon (Fv-4K) and the dikaryon (Fv-4) were resolved into six and eight bands, respectively. The sizes of the chromosomes ranged from 1.9 to 6.0 megabase (Mb) pairs. Each of the separated bands of chromosomal DNA was identified by use of five cloned probes. The number of these chromosomes was estimated to be 6 and 12, respectively; and the size of the entire genome was estimated to be about 20.1 and 38.6Mb, respectively. From a comparison of the hybridization patterns, the existence of allelic chromosomes of different sizes was deduced in the Fv-4 strain. 相似文献
76.
DNA polymorphism in the chicken growth hormone gene: Association with egg production 总被引:3,自引:0,他引:3
Norio KANSAKU Asako NAKADA Hisato OKABAYASHI Daniel GUÉMENÉ Urs KUHNLEIN David ZADWORNY Kiyoshi SHIMADA 《Animal Science Journal》2003,74(3):243-244
Restriction fragment length polymorphic markers in the chicken growth hormone (GH) gene were tested for their association with egg production traits. Alleles of GH were determined in 3 non‐inbred strains from different genetic bases. The frequency of PS1 (+) allele in the three strains was very low in contrast to the layer strain previously reported. Results of the present study indicate that the frequency of PS (+) is related to egg production and that the PS1 (+) allele may be used as a genetic marker for selection in egg production. 相似文献
77.
Fumie Kawasaki Ioanna Katsiadaki Alexander P. Scott Takahiro Matsubara Kiyoshi Osatomi Kiyoshi Soyano Akihiko Hara Koji Arizono Masaki Nagae 《Fish physiology and biochemistry》2003,28(1-4):425-425
Two types of spiggin cDNAs were isolated from the three-spined stickleback. Northern blot analysis revealed that glue protein is composed of multiple spiggin molecules, and that their synthesis in kidney is strongly up-regulated by androgens. 相似文献
78.
Makoto NISHIZAWA Nobuaki TAKAHASHI Kumiko SHIMOZAWA Takako AOYAMA Kouichi JINBOW Yukari NOGUCHI Kiyoshi HORITA Hideo BANDO Takashi YAMAGISHI 《Fisheries Science》2003,69(3):639-643
ABSTRACT: Four steroidal ketones were isolated from the holdfast of cultivated Laminaria japonica . The structures were characterized as ergosta-4,24(28)-diene-3-one (1), ergosta-4,24(28)-diene-3,6-dione (2), stigmasta-4,24(28)-diene-3-one (3) and stigmasta-4,24(28)-diene-3,6-dione (4), by spectral data. Compounds 2 and 4 were shown to be cytotoxic against the MCF-7 human breast cancer cell, and the growth of MCF-7 was inhibited by 96% and 79%, respectively, at 10 µg/mL. It is the first report on the isolation of cytotoxic steroidal ketones from the kelp in the genus of Laminaria. 相似文献
79.
SUMMARY: Laboratory-hatched juvenile yellowtails (mean fork length, 9.3 cm) were reared for 2 months in two groups on different kinds of food, mysid and squid in one group and fish in the other, and the gustatory neural responses to seven chemicals (adenosine-5'-monophosphate, alanine, arginine, betaine, proline, tryptophan, and valine) were recorded in fish before and after the 2-month rearing period. Large variances in the responses to some chemicals were noticed in the juveniles before the rearing experiment. Mann–Whitney U -tests on the neural responses indicated significant changes in the magnitude of the responses to valine and some other chemicals relative to that for proline or tryptophan between the pre- and the two post-rearing groups. No significant differences in the response magnitude for the seven chemicals were observed for the two post-rearing groups suggesting that the response changes during the 2-month rearing might have been intrinsic and not due to specific food items in the diet. The dose–response relationship for some chemicals was also examined in the juveniles before and after the 2-month rearing. A slight lowering of threshold was noticed for alanine and valine after the rearing. Data on the responses of wild yellowtails were in support of the changing responsiveness of gustatory receptors during development of juvenile yellowtails. 相似文献