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191.
To identify the cement-hardening inhibitory components of hannoki (Japanese alder,Alnus japonica Steud.), methanol extractives were fractionated by successive organic solvent extraction and column chromatography. Chromatographie analysis and inhibitory indices of the solvent-soluble fractions suggested that glucose and sucrose seem to be the main cement-hardening inhibitory components of Japanese alder. As these compounds are metabolized in vivo even after cutting, the particles after withering are desirable as raw material for wood-cement board. 相似文献
192.
Seiichi Yasuda Eri Hamaguchi Yasuyuki Matsushita Hideyuki Goto Takanori Imai 《Journal of Wood Science》1998,44(2):116-124
Highly condensed lignin can be transformed by three reactions — phenolation, hydroxymethylation, and neutral sulfonation — to water-soluble lignosulfonate. To elucidate reactivities and products in the latter two reactions, simple compounds were selected as lignin model compounds. With hydroxymethylation of creosol at 60°C, the yield of a condensed-type product with the diarylmethane structure was less than 10%. Hydroxymethylation of 1-guaiacyl-1-p-hydroxy-phenylethane (compound VI) as a phenolized guaiacyl lignin model compound gave four compounds. The initial reaction introduced the hydroxymethyl group mainly in the guaiacyl nucleus, and the additional reaction created two hydroxymethyl groups in the p-hydroxyphenyl nucleus. Contrary to our estimation, treatment of the models with 13C-labeled formaldehyde (H13CIIO) did not form any diarylmethane structure. Neutral sulfite treatment of hydroxymethylated products gave corresponding sulfonates in high yields. Phenolized guaiacylglycerol--aryl ether (compound XVI) showed a reactivity similar to that of compound VI.This paper was presented at the 45th and 46th annual meetings of the Japan Wood Research Society at Tokyo and Kumamoto, April 1995 and April 1996, respectively 相似文献
193.
To isolate and identify the cement-hardening inhibitory components of keyaki (Japanese zelkova, Zelkova serrata Makino), methanol extractives containing inhibitory components were fractionated by successive organic solvent extraction
and column chromatography, and the inhibition of these fractions was determined. Spectroscopic analysis of one isolated compound
identified it to be keyakinin with the C-glucoside structure of a flavonol. According to the inhibitory indices, the compound
was found to be the main cement-hardening inhibitory component of keyaki. Extraction of keyaki with hot water or a blend of
keyaki with up to 30% hinoki as a suitable species diminished the cement-hardening inhibition of wood-cement board to a great
extent, suggesting that such treatments are economical countermeasures to this inhibition.
Received: April 17, 2002 / Accepted: June 24, 2002
Acknowledgments The authors thank Dr. W. Nagadomi, Nichiha Co., for providing Japanese zelkova wood. This research was conducted with the
support of the TOSTEM Foundation for Construction Materials Industry Promotion. 相似文献
194.
We used unbiased next-generation sequencing (NGS) to detect unknown viruses in cats. Serum or plasma samples were obtained from clinically ill cats with suspected acute viral infections. Nucleic acid was extracted from serum or plasma samples to construct a complementary DNA library for NGS. Comprehensive nucleotide sequencing analyses enabled detection of the genomes of various viruses, including the severe fever with thrombocytopenia syndrome virus, feline immunodeficiency virus, feline morbillivirus, parvovirus, and Torque teno felis virus. Our findings indicate that comprehensive nucleotide analyses of serum or plasma samples can be used to detect infections with unknown viruses in cats. 相似文献
195.
Erry Purnomo Athaillah Mursyid Muhrizal Syarwani Ahmadi Jumberi Yasuyuki Hashidoko Toshihiro Hasegawa Saori Honma Mitsuru Osaki 《Soil Science and Plant Nutrition》2005,51(5):679-681
Local farmers who living in South Kalimantan (Banjarese farmers) apply almost none of phosphatic (P) fertilizers to grow local rice varieties. This practice has been adopted for many years. We have investigated the mechanisms involved in P availability for the crop. This study focuses on identifying microorganisms involved in solubilizing insoluble P. The study was conducted in Balandean District, South Kalimantan, Indonesia. The soil was classified as acid sulfate soil. Three out of 8 rice varieties grown were selected for net P balance in the soil-plant system and the microbial studies. We found that the P uptakes by the rice crop was much higher than the sum of P released from soil, water and soil microbial biomass P. It was also observed that these soils harboured bacteria and fungi that have the capability of dissolving aluminium phosphate (AIPO4 ) and tricalcium phosphate [Ca3 (PO4 )2 ].
Based on the area of clear zone on plates, it seem that there were variations of ability in dissolving Al-P or Ca-P. DNA sequence analysis shown that Burkholderia sp. was the common P solubilizing bacterium found in the rhizosphere of rice varieties Siam Unus, Siam Ubi and Siam Puntal. The presence of other bacteria was specific for each rice variety grown. 相似文献
Based on the area of clear zone on plates, it seem that there were variations of ability in dissolving Al-P or Ca-P. DNA sequence analysis shown that Burkholderia sp. was the common P solubilizing bacterium found in the rhizosphere of rice varieties Siam Unus, Siam Ubi and Siam Puntal. The presence of other bacteria was specific for each rice variety grown. 相似文献
196.
Yasuyuki Itano Munehiro Warashina Kaihei Takeda Hiroshi Bandow Yasuaki Maeda Masanobu Tanaka 《Water, air, and soil pollution》2001,130(1-4):403-408
The oxidation of nitric oxide (NO) to nitrogen dioxide (NO2), the initial step in formation of nitric acid, was analyzed based on atmospheric observations in urban central Osaka, Japan, focusing the relation with the behavior of photoreactive hydrocarbon (HC) species. Simultaneous observation at two vehicle exhaust monitoring stations, one has higher oxidation ratio of NO (NO2/NOx) and the other has lower NO2/NOx, in November 1998 and May 1999, had been held and investigated in current report. By using concentration ratios of reactive HCs to acetylene, obvious relation between NO2/NOx and HCs reaction was implied. In November observations, decline of aromatics to acetylene ratios with increasing NO2/NOx were observed at one station, while not appeared at the other station. Opposite tendencies were observed at the two sampling stations from November to May, implying complicated regional characteristics of photochemistries. 相似文献
197.
198.
Yasuyuki Morimoto Patrick Maundu Makoto Kawase Hiroshi Fujimaki Hiroko Morishima 《Genetic Resources and Crop Evolution》2006,53(5):963-974
The present study was performed to investigate genetic diversity of Kenyan landraces of the white-flowered gourd (Lagenaria siceraria), which exhibits tremendous morphological variation. RAPD analyses were performed on 53 landraces of the cultivated species
L. siceraria and 42 accessions of three wild species (40 L. sphaerica, 1 L. abyssinica, and 1 L. breviflora). A total of 432 polymorphic bands were detected using 54 primers. The four species were clearly differentiated from one
another. Intra-specific variations were investigated with L. siceraria and its wild relative L. sphaerica. Landraces of the cultivated species collected from different ethnic communities or regions were differentiated. Morphological
variations were not associated with RAPD variations. Bitter landraces collected in Maasai communities showed two specific
RAPD bands. In the wild species, accessions collected from the eastern and western sides of the Great Rift Valley were genetically
differentiated from each other. In both species, genetic and geographical distance matrices computed among all pairs of accessions
were significantly correlated, implying that the observed geographical variation can be explained by the 'Isolation by distance
model'. Progeny plants derived from a common mother in L. siceraria showed a low level of segregation in RAPD pattern, suggesting that collected landraces are cultivated, maintaining their
inherent traits although they are monoecious and insect-pollinated, whereas the wild relative L. sphaerica showed a higher level of segregation. The morphological diversity observed among landraces of L. siceraria is the result of human selection and their genetic identities are maintained by inbreeding probably resulting from frequent
self-pollination. 相似文献
199.
Jeon HJ Noda M Maruyama M Matoba Y Kumagai T Sugiyama M 《Journal of agricultural and food chemistry》2006,54(26):9827-9833
The present study found that the n-hexane extract of freeze-dried sake lees inhibits tyrosinase activity and showed that the constituents isolated from the n-hexane extract are the mixture of triacylglycerols. The inhibitory effects of triolein and trilinolein found as the triacylglycerols were examined using tyrosinases from mushroom and Streptomyces castaneoglobisporus. The IC50 values of the triacylglycerol mixture for the oxidase activity on mushroom and Streptomyces tyrosinases were 20 and 0.14 microg/mL, respectively. The IC50 values of trilinolein for the oxidase activity on mushroom and Streptomyces tyrosinases were 8.4 and 0.1 microM, respectively. However, the inhibitory effect of triolein (IC50=30 microM) was lower than that of trilinolein, even when the Streptomyces tyrosinase was used for the assay. Kinetic analyses indicate that both trilinolein and triolein inhibit the tyrosinase activity noncompetitively. When transformed with a plasmid carrying the Streptomyces tyrosinase gene, the melanin-synthesizing ability of the transformed Escherichia coli host was dose-dependently interfered with by trilinolein. 相似文献
200.
Nakano Y Matsuo S Tani H Sasai K Baba E 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(4):373-374
An eardrop solution of beta-thujaplicin was examined for therapeutic effects on canine Malassezia-related otitis externa. Half to one ml of beta-thujaplicin solution of 100 microg/ml including DMSO 2% was injected everyday into both external ear canals of 31 cases for test-of-cure agreement. Fifteen score phases were established from the symptoms and cerumen smear biopsy findings, and score changes were recorded at least once a week. The means of the second and the third inspection day scores decreased significantly more than the previous value of each. In addition, the numbers of yeast-like organisms clearly decreased. These results suggest that beta-thujaplicin eardrops are effective for Malassezia-related otitis externa in dogs. 相似文献