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31.
Katsuyoshi Hamada Yuji Tsutsumi Kazuchika Yamauchi Kazuhiko Fukushima Tomoaki Nishida 《Journal of Wood Science》2003,49(4):333-338
Ferulic acid (FA), tetradeuteroferulic acid (DFA), sinapic acid (SA), or heptadeuterosinapic acid (DSA) was exogenously supplied to poplar (Populus alba L.) callus. Administration of FA or SA increased the lignin content of the callus to about twice that of the control callus. Gas chromatographic analysis of the alkali hydrolysate of the cell wall residue revealed that only a trace amount of SA was bound to the cell wall, and the amount of FA was less than 2% of the total callus lignin. Thioacidolysis of the DFA-treated callus indicated that DFA is effectively converted to both coniferyl and sinapyl alcohols and then incorporated into the corresponding lignin. Incorporation of DSA into syringyl lignin or guaiacyl lignin was not observed, but yields of syringyl lignin thioacidolysis products were markedly increased by DSA treatment of the callus. These results suggest that SA may not be a precursor of sinapyl alcohol and syringyl lignin per se, but it may induce or enhance the biosynthesis of syringyl lignin in poplar callus. 相似文献
32.
Kazuchika Yamauchi Natthanon Phaiboonsilpa Haruo Kawamoto Shiro Saka 《Journal of Wood Science》2013,59(2):149-154
Japanese beech (Fagus crenata) wood was treated by two-step semi-flow hot-compressed water (the first stage: 230 °C/10 MPa/15 min, the second stage: 270 °C/10 MPa/15 min), and produced lignin-derived products in the hot-compressed water-soluble portions at the first and second stages, and the final residue of the second stage was characterized with alkaline nitrobenzene oxidation method and gel permeation chromatographic analysis. As a result, the lignin-derived products at the first stage, where hemicellulose was also decomposed, consisted of lignin-based monomers and dimers and oligomers/polymers in the water-soluble portion. A large part of the oligomers/polymers was, however, recovered as the precipitate during 12 h setting after hot-compressed water treatment. By the analysis of nitrobenzene oxidation products, there were relatively higher contents of ether-type lignin in the precipitate at the first stage than in original beech wood. Since the ether linkages of lignin are more preferentially cleaved by this hot-compressed water, lignin-based polymeric fractions were flowed out from the porous cell walls from which hemicellulose was removed. On the other hand, at the second stage condensed-type lignin remained in the precipitate and residue. Based on these results, decomposition behavior of lignin in Japanese beech wood as treated by the two-step semi-flow hot-compressed water was discussed regarding the topochemistry of lignin structure. 相似文献
33.
Tomohito ISHIZUKA Jun TAMURA Tsukasa NAGARO Kanako SUDO Takaharu ITAMI Mohammed Ahamed UMAR Kenjirou MIYOSHI Tadashi SANO Kazuto YAMASHITA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2014,76(12):1577-1582
Effects of intermittent
positive pressure ventilation (IPPV) on cardiopulmonary function were evaluated in horses
anesthetized with total intravenous anesthesia using constant rate infusions of
medetomidine (3.5 µg/kg/hr), lidocaine (3 mg/kg/hr), butorphanol (24
µg/kg/hr) and propofol (0.1 mg/kg/min) (MLBP-TIVA). Five horses were
anesthetized twice using MLBP-TIVA with or without IPPV at 4-week interval (crossover
study). In each occasion, the horses breathed 100% oxygen with spontaneous ventilation
(SB-group, n=5) or with IPPV (CV-group, n=5), and changes in cardiopulmonary parameters
were observed for 120 min. In the SB-group, cardiovascular parameters were maintained
within acceptable ranges (heart rate: 33–35 beats/min, cardiac output: 27–30
l/min, mean arterial blood pressure [MABP]: 114–123 mmHg, mean
pulmonary arterial pressure [MPAP]: 28–29 mmHg and mean right atrial pressure [MRAP]:
19–21 mmHg), but severe hypercapnea and insufficient oxygenation were observed (arterial
CO2 pressure [PaCO2]: 84–103 mmHg and arterial O2
pressure [PaO2]: 155–172 mmHg). In the CV-group, normocapnea (PaCO2:
42–50 mmHg) and good oxygenation (PaO2: 395–419 mmHg) were achieved by the IPPV
without apparent cardiovascular depression (heart rate: 29–31 beats/min, cardiac output:
17–21 l /min, MABP: 111–123 mmHg, MPAP: 27–30 mmHg and MRAP: 15–16 mmHg).
MLBP-TIVA preserved cardiovascular function even in horses artificially ventilated. 相似文献
34.
Japanese beech (Fagus crenata) was treated with semi-flow hot-compressed water at various temperatures of 150–230 °C under 10 MPa. The obtained various products were then analyzed with matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF/MS). In a temperature range of 150 °C up to 210 °C, however, no hydrolyzed products were found, and at 210 °C/10 MPa, O-acetyl-4-O-methylglucuronoxylo-oligosaccharides (X n Ac m MG i ) and O-acetyl-xylo-oligosaccharides (X n Ac m ) were obtained, indicating the first cleavage of native xylan β-1,4-glycosidic linkages followed by a cleavage of α-1,2-glycosidic linkage in 4-O-methylglucuronic acid (MG) residue at mainly 220–230 °C under 10 MPa. At subsequent stage of 230 °C/10 MPa, X n Ac m were predominantly recovered. As the treatment was prolonged at 230 °C, X n Ac m were reduced, but remained to some extent, indicating that the acetyl group which is hydrolyzed to be acetic acid is more resistant than MG residue. In such a stage of treatment, cellulose started to hydrolyze to cello-oligosaccharides. These lines of evidence can clearly indicate the hydrolysis pathway of native O-acetyl-4-O-methylglucuronoxylan as treated by hot-compressed water. Thus, xylo-oligosaccharides recovered in a very early stage of the semi-flow hot-compressed water treatment preserve native O-acetyl-4-O-methylglucuronoxylan. 相似文献
35.
Mori H Mizobe Y Inoue S Uenohara A Takeda M Yoshida M Miyoshi K 《The Journal of reproduction and development》2008,54(5):364-369
The present study was carried out to examine the parthenogenetic development of pig oocytes treated with different concentrations of cycloheximide for different durations following activation by ultrasound stimulation. When oocytes were treated with 10 microg/ml cycloheximide for different durations, the blastocyst formation rate of oocytes treated for 5 h was significantly (P<0.05) higher than those of oocytes treated for 0-2 h. The blastocyst formation rate of oocytes treated with 10 microg/ml cycloheximide for 5 h was significantly (P<0.05) higher than those of oocytes treated with 0-5 or 15-20 microg/ml cycloheximide for the same duration. When oocytes were treated with different concentrations of cycloheximide for 2 h, however, the blastocyst formation rate of oocytes treated with 40 microg/ml cycloheximide was significantly (P<0.05) higher than those of oocytes treated with 0-10 or 50 microg/ml cycloheximide. The blastocyst formation rate of oocytes treated with 10 microg/ml cycloheximide for 5 h was not significantly different from that of oocytes treated with 40 microg/ml cycloheximide for 2 h. These treatments did not affect the activation status of oocytes compared with controls that were not treated with cycloheximide. The results of the present study showed that cycloheximide improves the parthenogenetic development of pig oocytes activated by ultrasound stimulation. 相似文献
36.
Miyoshi K Mori H Yamamoto H Kishimoto M Yoshida M 《The Journal of reproduction and development》2008,54(2):117-121
The present study was carried out to examine whether demecolcine and sucrose affect the formation of a cytoplasmic protrusion containing chromosomes in pig oocytes independently or in combination. In the presence of 20 mM sucrose, the rates of oocytes with a cytoplasmic protrusion after culture for 60 min with 0.2-1.0 microg/ml demecolcine were significantly higher than those with 0.01-0.05 microg/ml demecolcine. When oocytes were cultured for 15 min in the presence of 0.2 microg/ml demecolcine and 20 mM sucrose, 35.1% of them extruded a cytoplasmic protrusion; this rate was significantly lower than those of oocytes cultured for 30-90 min. In the presence of 0.2 microg/ml demecolcine, significantly fewer oocytes extruded a cytoplasmic protrusion after culture for 30 min with 160 mM sucrose than with 0-80 mM sucrose. Significantly more oocytes extruded a cytoplasmic protrusion after culture for 30 min with 0.2 microg/ml demecolcine than without it, regardless of the presence or absence of 20 mM sucrose. In 88.9-100% of the oocytes, the cytoplasmic protrusions contained chromosomes with no significant differences among the different concentrations of demecolcine and sucrose and among the different treatment times. The results of the present study show that the cytoplasmic protrusion containing chromosomes in the pig oocyte is attributable to demecolcine, but sucrose does not affect its formation. 相似文献
37.
Xin Lu Kazuchika Yamauchi Natthanon Phaiboonsilpa Shiro Saka 《Journal of Wood Science》2009,55(5):367-375
A two-step hydrolysis of Japanese beech (Fagus crenata) was conducted by semi-flow treatment with hot-compressed water. The first treatment stage was conducted at 230°C/10 MPa
for 15 min and the second at 270°C/10 MPa for 15 min. Hemicellulose and lignin were found to be hydrolyzed in the first stage,
while crystalline cellulose was hydrolyzed in the second stage. The treatment solubilized 95.6% of the Japanese beech wood
flour into water with 4.4% remaining as water-insoluble residue, which was composed mainly of lignin. Hydrolysis products
from the first stage were xylose and xylo-oligosaccharides, glucuronic acid and acetic acid from O-acetyl-4-O-methylglucuronoxylan, and hydrolyzed monomeric guaiacyl and syringyl units and their dimeric condensed-type units from lignin.
Products from the second hydrolysis stage were glucose and cello-oligosaccharides from cellulose. The dehydrated products
levoglucosan, 5-hydroxymethylfurfural (5-HMF), and furfural, as well as fragmented products glycolaldehyde, methylglyoxal,
and erythrose, were recovered in the first stage from hemicellulose, and to a greater extent in the second stage from cellulose.
Furthermore, organic acids such as glycolic, formic, acetic, and lactic acids were recovered in both stages. Based on these
lines of evidence, decomposition pathways of O-acetyl-4-O-methylglucuronoxylan and cellulose are independently proposed. 相似文献
38.
A. RUNGSIPIPAT S. TATEYAMA R. YAMAGUCHI K. UCHIDA N. MIYOSHI 《Research in veterinary science》1999,66(3):205-210
An immunohistochemical study of various visceral organs of normal adult dogs, cats, pigs, horses, cows, and chickens (five of each species) and of 185 spontaneous canine tumours was carried out using paraffin wax sections and a commercially available antibody to the human c- yes oncogene product. Among the adult normal tissues of six animal species, epithelial cells of the proximal and distal renal tubules, the myocardium, hepatocytes, cerebellar Purkinje cells and adrenal cortical cells were positive for c- yes product. Among the foetal tissues of dogs and chickens, a positive reaction was observed on canine chorionic villi cells and chick yolk sac surface epithelium, and on epithelial cells of the renal tubules, hepatocytes and the myocardium. These findings suggest that the c- yes proto-oncogene may play a physiological role in the cell growth and metabolism of these adult and foetal tissues. Of the 185 tumours tested, 59 (31.9 per cent) expressed the c- yes oncogene product. The c- yes -positive tumours accounted for 44.4 per cent (12/27) of the skin tumours, 5.5 per cent (1/18) of the round cell tumours, 35. 7 per cent (10/28) of the soft tissue tumours, 21.4 per cent (3/14) of the testicular tumours, 29.1 per cent (23/79) of the mammary tumours, and 52.6 per cent (10/19) of the other tumours types. Expression of the c- yes oncogene appeared to be common in spontaneously arising canine tumours, and the degree of expression varied considerably by tumour type. 相似文献
39.
The effects of Ca(2+) concentration in activation medium and cytochalasin B treatment after activation on the parthenogenetic development of pig oocytes were examined. In addition, cloned embryos derived from miniature pig somatic cells were activated under optimal conditions and the effects of Ca(2+) in fusion medium on the development of embryos after activation was examined. When oocytes were activated in 0.1 mM Ca(2+) and then treated with cytochalasin B, the blastocyst formation rate (28.6%) was significantly higher than those activated in 0-0.05 or 1.0 mM (11.0-18.3%). Treatment with cytochalasin B decreased the second polar body extrusion rate of activated oocytes. The presence or absence of Ca(2+) in fusion medium did not affect the fusion rate of miniature pig somatic cells with recipient oocytes. A few cloned embryos developed to the blastocyst stage (2.7-9.0%) without an additional activation treatment. On the other hand, significantly more embryos developed to the blastocyst stage after activation treatment when they were fused in the absence (28.9%) of Ca(2+) rather than the presence (16.5%) of it. These results show that the highest blastocyst formation rate for miniature pig cloned embryos is obtained when donor cells and recipient oocytes are fused in the absence of Ca(2+) and then activated in 0.1 mM Ca(2+) and treated with cytochalasin B. 相似文献
40.
Activation and parthenogenetic development of pig oocytes exposed to ultrasound in media containing different concentrations of Ca2+ 总被引:1,自引:0,他引:1
The present study was carried out to examine the activation and parthenogenetic development of pig oocytes after exposure to ultrasound in sorbitol media supplemented with different concentrations of Ca2+. The activation rates (68.8-75.6%) of oocytes exposed to ultrasound in media containing 0.1-1.0 mM Ca2+ were significantly (P<0.05) higher than those (54.3-58.3%) of oocytes exposed to ultrasound in media containing 0-0.05 mM Ca2+. When oocytes were exposed to ultrasound in media containing 0.1-0.5 mM Ca2+, the blastocyst formation rates (20.5-21.3%) were significantly (P<0.05) higher than those (3.3-6.0%) of oocytes exposed to ultrasound in media containing 0, 0.05 or 1.0 mM Ca2+. The results of the present study showed that the concentration of Ca2+ in the medium used for exposure to ultrasound affects the activation and parthenogenetic development of pig oocytes and showed that the optimal Ca2+ concentration is 0.1-0.5 mM. 相似文献