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41.
Samples described in the previous paper were analyzed for humus composition by the method of Kumada el al,, elementary composition of humic acids, nitrogen distribution among humic acid, fulvic acid, and humin, and organic matter composition by the modified Waksman method. The samples obtained by physical fractionation from each horizon of Higashiyama soil were as follows: f1 and f2 from the L layer, f1, f2 and f3 from the F layer, f1 f2, sand, silt, and clay fractions from the H-A and A horizons. With the progress of decomposition, the following tendencies were rather clearly observed. The extraction ratio of soluble humus, amounts of humic acid and fulvic acid, and PQ, value tended to increase with some exceptions. The degree of humification of humic acid proceeded. Most humic acids belonged to the Rp type, but those of the clay fractions belonged to the B type. As for the elementary composition of humic acid, transitional changes from the Lf1 to the clay fraction of the A horizon were observed. But differences in elementary composition among humic acids were far less, compared with those among whole fractions. Nitrogen contents in humic, fulvic, and humin fractions increased with the progress of decomposition and humiliation, and the largest relative increase was found in fulvic acid nitrogen. According to the modified Waksman's method, the amounts of residues and protein increased, while the total amounts of each extract, except for the HCl extract, and the amounts of sugars and starch, phenolic substances, hemicelluloses and pectin, and cellulose decreased. Sugars and starch comprised only a small portion of the hot water extract, and polyphenols substances comparable to sugars and starch were also found in the extract. Hemicelluloses and pectin accounted for only about one-half of the HCl extract. Several characteristic differences in the elementary composition of extracts and residues were found. Pheopigments existed in benzene-ethanol extracts and their amounts seemed to decrease from Lf1 to Ff2. 相似文献
42.
The results of elementary analysis of each fraction separated physically from each horizon of five forest soils were described. The biggest fraction was Lf2 (fresh litter) in L layers, Ff2 (>2 mm) or Ff2 (2-1 mm) is F layers and Hf4 in H layers. Of all the changes in various parameters which accompanied decomposition and humification, the change in C/N ratio was the most obvious; the C/N ratio for plant remains easily decreased to 25 or 30 during decomposition, but any further decrease in this value occurred with difficulty. It was specifically pointed out that Hf7 and Hf2 were fairly different materials from the other fractions. As for A horizons, both carbon and nitrogen contents increased, and CIN ratios decreased in the order of sand, silt and clay fractions. 相似文献
43.
Preparation of strongly acidic cation-exchange resins from gymnosperm acid hydrolysis lignin 总被引:1,自引:0,他引:1
The chemical preparation of strongly acidic cation-exchange resin from sulfuric acid lignin (Klason lignin) (SAL), a typical acid hydrolysis lignin, was investigated. Sulfonation of resinified SAL itself gave a resin with an ion-exchange capacity of 2.3 mEq/g. After resinification with formaldehyde, the phenolized SAL with a reactivep-hydroxyphenyl group yielded a resin with an ion-exchange capacity of 3.2 mEq/g. The latter capacity is superior to that of the corresponding commercial phenol-type resins (2–3 mEq/g), but did not reach the level of the corresponding commercial styrene-type resins (4-5 mEq/g).This paper was presented at the 43th Lignin Symposium, Fuchu, October 1998 相似文献
44.
45.
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
46.
Yasuyuki TANAHASHI Ban WANG Yuri MURAKAMI Toshihiro UNNO Hayato MATSUYAMA Hiroshi NAGANO Seiichi KOMORI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):203-211
In order to investigate the effects of (SKF), which is a non-selective cationic channel blocker, on
K+ channel currents, we recorded currents through ATP sensitive K+ (IKATP),
voltage-gated K+ (IKv) and Ca2+ activated K+ channels
(IBK) in the absence and presence of SKF in single small intestinal myocytes of mice with
patch-clamp techniques. SKF (10 µM) reversibly abolished IKATP that was induced by
cromakalim (10 µM), which is a selective ATP sensitive K+ channel opener. These
inhibitory effects were induced in a concentration-dependent and voltage-independent manner. The 50%
inhibitory concentration (IC50) was 0.85 µM, which was obviously lower than that
reported for the muscarinic cationic current. In addition, SKF (1 µM ≈ the IC50
value in IKATP suppression) reversibly inhibited the IKv that was induced by repetitive
depolarizing pulses from −80 to 20 mV. However, the extent of the inhibitory effects was only ~30%. In
contrast, SKF (1 µM) had no significant effects on spontaneous transient IBK and
caffeine-induced IBK. These results indicated that SKF inhibited ATP sensitive K+
channels and voltage-gated K+ channels, with the ATP sensitive K+ channels being more
sensitive than the voltage-gated K+ channels. These inhibitory effects on K+ channels
should be considered when SKF is used as a cationic channel blocker. SKF96365相似文献
47.
Yasuyuki?MatsushitaEmail author Akihiro?Kakehi Shigeru?Miyawaki Seiichi?Yasuda 《Journal of Wood Science》2004,50(2):136-141
To elucidate the formation and chemical structures of water-soluble material in acid-soluble lignin (ASL), lignin aromatic nuclei model compounds of creosol (I) and 5-methoxycreosol (II) were reacted with xylose or xylan in the presence of apocynol as a counterpart for condensation in 72% sulfuric acid (SA). The reaction of I gave mainly condensation product. However, the condensation reaction of II with apocynol was suppressed because of steric hindrance from the methoxyl group, and II yielded a C-xyloside after refluxing in 3% SA together with condensation products. To obtain information on CHCl3-soluble material in ASL, model compounds of arylglycerol--aryl ethers with guaiacyl (VIII) and syringyl (X) nuclei were treated by the Klason procedure. VIII gave only insoluble polymerized product, while X gave insoluble polymerized product and CHCl3-soluble low molecular weight products, which were dissolved in 3% SA. These results prove earlier views that water-soluble material in ASL consists of condensation products formed from syringyl lignin and monosaccharide units in hemicellulose. In addition, the CHCl3-soluble material in ASL appears to be composed of low molecular weight degradation products from SA treatment of Klason lignin with the syringyl nucleus.Part of this report was presented at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001 and at the 47th Lignin Symposium, Fukuoka, October 2002, and was reviewed in Mokuzai Gakkaishi (2002) 48:55–62 相似文献
48.
Preparation of anion-exchange resins from pine sulfuric acid lignin,one of the acid hydrolysis lignins 总被引:4,自引:0,他引:4
To utilize acid hydrolysis lignin effectively, chemical conversion to anion-exchange resin was investigated by two methods. Sulfuric acid lignin (SAL) was selected as a typical acid hydrolysis lignin in this experiment. Because it is less reactive, SAL was phenolated with sulfuric acid catalyst to yield reactive phenolized SAL (P-SAL) with p-hydroxyphenyl nuclei. One method was the restricted resinification of P-SAL followed by the Mannich reaction with formaldehyde and dimethylamine to yield a weakly basic anion-exchange resin with an ion-exchange capacity of 2.4mEq/g. Another method was to react resinified P-SAL with glycidyltrimethylammonium chloride to yield a strongly basic anion-exchange resin with an ion-exchange capacity of 2.0mEq/g. The reaction of a simple P-SAL model compound with an epoxide suggested that the phenolic hydroxyl group of the p-hydroxyphenyl nucleus had slightly higher reactivity than that of the guaiacyl nucleus.Part of this report was presented at the 47th Lignin Symposium, Fukuoka, October 2002 相似文献
49.
Watanabe D Hirano T Sugimoto Y Ogata Y Abe S Ando T Ohtsuka H Kunieda T Kawamura S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(12):1251-1255
Blood examinations and genotyping of Factor XI (F11) were performed in growth retardation Japanese Black cattle and their dams. Genotyping of F11 revealed that the recessive homozygous and heterozygous genotype frequencies were 5.2% and 50.0% in the Claudin-16 (CL-16) deficiency group (n=58), 0% and 14.2% in the renal dysplasia group (n=7), 0% and 26.1% in the non-CL-16 deficiency nephritis group (n=23), 8.9% and 46.7% in the hypogenesis syndrome group (n=45), 6.2% and 25.0% in the neonatal weak calf syndrome group (n=32), 9.1% and 38.6% in the respective dams group (n=44), 0% and 23.1% in the normal cattle group (n=13), and 5.9% and 38.2% in total (n=222), respectively. These results showed that the carrier rate of F11 deficiency was high in Japanese Black cattle, and that the CL-16 deficiency, hypogenesis syndrome, neonatal weak calf syndrome, and dams groups had a large amount of recessive homozygous genotype than the other groups. No abnormal bleeding was observed clinically in the present study, and 4 of the recessive homozygous dams showed normal growth and parturition. 相似文献
50.
Kakizaki T Hamada N Funayama T Sakashita T Wada S Hohdatsu T Natsuhori M Sano T Kobayashi Y Ito N 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(12):1269-1273
High linear energy transfer (LET) heavy charged particles have previously been applied clinically to human cancer radiotherapy because of their excellent physical properties of selective dose distribution and higher relative biological effectiveness (RBE) for human; however, such an approach has yet to be applied to cat patients. The present study investigates the biological effectiveness of low-LET gamma-rays (0.2 keV/micro m) compared to high-LET carbon ions (114 keV/micro m) in feline T- lymphocyte FeT-J cells. Clonogenic survival analysis revealed that the RBE value of carbon ions was 2.98 relative to a 10% survival dose (D(10)) by gamma-rays, and that the inactivation cross-section in cells exposed to gamma-rays and carbon ions was 0.023 and 38.9 micro m(2), respectively. Terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL) analysis revealed that TUNEL-positive frequency in carbon-irradiation cells is higher than for gamma-irradiated cells against exposure to the same physical doses, but that very little difference in TUNEL-positive frequency is observed between cells exposed to the respective D(10) dose of gamma-rays. Our data thus indicate that carbon ions are more effective for cell killing than gamma-rays at the same physical doses, but kill cells to an extent that is comparable to gamma-rays at the same biological doses. Carbon ion radiotherapy is therefore a promising modality for cat patients. 相似文献