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11.
Takeshi Katayama Jyoji Tsutsui Kazuo Tsueda Takao Miki Yasuhiro Yamada Murao Sogo 《Journal of Wood Science》2000,46(6):458-465
When (±)--oxo-guaiacylglycerol--(vanillic acid) ether (1) is degraded byFusarium solani M-13-1, the-ketone is initially reduced to giveerythro andthreo guaiacylglycerol--(vanillic acid) ethers (2), arylglycerol--aryl ethers, both of which are enantiomerically pure. The absolute configuration in each2 was determined by Mosher's method; the products were converted to,-di-(R)--methoxy--trifluoromethylphenylacetates (MTPA esters) (3) oferythro (-)- andthreo (+)-veratrylglycerol--(methyl vanillate) ethers (3), whose1H nuclear magnetic resonance (NMR) spectra were examined and compared with those of four di-(R)-MTPA ester (3) diastereomers from chemically synthesizederythro (±)-3 andthreo (±)-3. To assign the- and-MTPA-OCH3 peaks, the1H NMR scans of several compounds that have substructures of 3 and their 3,4,5-trimethoxyphenyl analogues were examined. When a racemic alcohol reacts with (R)-MTPA to give a pair of (R)-MTPA ester diastereomers, the value was defined as the absolute value of the difference in the1H chemical shifts of the peak between the diastereomers. It was found that the values of-MTPA-OCH3 were larger than those of-MTPA-OCH3 owing to a shielding effect of the veratryl ring located on the-MTPA-OCH3, and that the-MTPA-OCH3 peaks in the 3,4,5-trimethoxyphenyl compounds shifted downfield relative to those in the veratryl compounds. On the basis of the1h NMR data of (R)-MTPA esters, the absolute configuration of the four chemically prepared diastereomers (3) were determined. The catabolicerythro
3 [fromerythro (-)-3] andthreo
3 [fromthreo (+)-3] were identical to (R, S, R)-erythro
3 and (R, S, S)- threo
3, respectively. An hydrogen species in the fungal reduction would attack the-ketone fromre-face of both (R)-1 and (S)-1, givingerythro (S, R)-2 andthreo (S, S)-2, respectively.Part of this paper was presented at the 33rd Lignin Symposium, Tsukuba, November 1988 相似文献
12.
Keiji?SakamotoEmail author Naoko?Miki Taiyo?Tsuzuki Takashi?Nishimoto Ken?Yoshikawa 《Journal of Forest Research》2003,8(4):303-309
In pine forests damaged by pine wilt disease, in western Japan, the effect of protection regimes of pine trees on the stand dynamics were examined in the following four stands: (1) lightly damaged stand (age 30–40 years) with no procedure in operation for protecting pine trees; (2) severely damaged stand (age 30–40 years) with no procedure in place for protecting pine trees; (3) severely damaged stand (age 50 years) with a selective cutting of infected trees; (4) severely damaged stand (age 30–40 years) with a selective cutting of infected trees. All the stands had been abandoned before the pine wilt disease damage. The understory structure of the severely damaged stand with no protection procedure was similar to that of the lightly damaged stand. Frequent invasion by tree species and acceleration in the growth of understory trees occurred after the dieback in the selective cutting stand. These results suggest that a deficiency in the canopy layer caused by the dieback resulted in low disturbance intensity in the early stages after the dieback, but the selective cutting increased the intensity by the reduction in the understory as well as the canopy layer. The intensity of the disturbance in the selective cutting stands was larger in the younger stand because it had a higher density of selectively cut pine trees. The different stand structure of pine forests occurred after the dieback because the intensity of the disturbance varied as a result of the selective cutting operation and the stand age. 相似文献
13.
14.
Shun HIRASAWA Miki SHIMIZU Yuumi MARUI Miori KISHIMOTO Seiichi OKUNO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2014,76(12):1603-1607
We designed a new method of
measuring the length of the ulnar nerve and determining standard values for F-wave
parameters of the ulnar nerve in clinically normal beagles. Nerve length must be precisely
measured to determine F-wave latency and conduction velocity. The length of the forelimb
has served as the length of the ulnar nerve for F-wave assessments, but report indicates
that F-wave latency is proportional to the length of the pathway traveled by nerve
impulses. Therefore, we measured the surface distance from a stimulus point to the spinous
process of the first thoracic vertebra (nerve length 1) and the anterior horn of the
scapula (nerve length 2) as landmarks through the olecranon and the shoulder blade
acromion. The correlation coefficients between the shortest F-wave latency and the length
of nerves 1, 2 or the forelimb were 0.61, 0.7 and 0.58. Nerve length 2 generated the
highest value. Furthermore, the anterior horn of the scapula was easily palpated in any
dog regardless of well-fed body. We concluded that nerve length 2 was optimal for
measuring the length of the ulnar nerve. 相似文献
15.
Lingli Yang Naoko H. Miki Naoko Matsuo Guosheng Zhang Linhe Wang Ken Yoshikawa 《农业科学与技术》2014,(3):251-259
duniperus sabina Linnaeus, an evergreen shrub with prostrate life form, can effectively prevent sand moving and is an important tree species for reforestation in semiarid areas of China. It has laterally distributed adventitious roots and a deeply distributed main root system. To detect water movement between the main root system and adventitious roots, we adopted heat pulse sensors using the Heat Ratio Method, a high precision method for measuring low sap flow rates. Two sensors were implanted in each individual in the stem between the main root system and adventitious roots, and another two in lateral stems distal to all the roots. Positive sap flows during nighttime, even under saturated air moisture conditions, were detected only between the main root system and adventitious roots under drought conditions, and the rate of flow increased as drought progressed and decreased or disappeared after rain events. The results demonstrated the existence of water movement from the main root system to adventitious roots, and combined with the high contribution of nighttime sap flow to transpiration (11%-16%) the results indicate that it also involves the process of hydraulic lift, a water movement from moist subsoil to dry surface soils. Integrated water use strategy between the main root system and adventitious roots via the process of hydraulic lift of soil water maximizes water acquisition efficiency from both subsoil water and water from rain pulses on the soil surface; this increases survivability in the water-limited environment of semiarid areas. 相似文献
16.
J. Shen Q. Zhao H. Tang F. Zhang Z. Feng T. Okita N. Ogura T. Totsuka 《Water, air, and soil pollution》1995,85(3):1299-1304
During the period from 25 May 1991 to 30 May 1992 the atmospheric concentrations and depositions of oxides of sulfur were continuously measured in a suburban masson pine forest which is currently experiencing severe dieback, in Chongqing, China. The annual mean concentrations of SO2 and particulate SO4 2? were 220 μ g/m3 (77 ppbv) and 32 μ g/m3 respectively. The atmospheric concentrations of these sulfur compounds were high in late autumn and winter. The annual wet and dry depositions of sulfur to the forest as measured by throughfall and stemflow were 93.1 and 46.6 kgSha?1a?1 respectively. These depositions are among the highest level ever reported in the world. Althogh the cause of the dieback of the masson pine trees has not been unequivocally determined, it is probable that the direct impact of SO2 is more likely the cause than acid deposition. 相似文献
17.
Expression cDNA cloning of the KGF receptor by creation of a transforming autocrine loop. 总被引:72,自引:0,他引:72
T Miki T P Fleming D P Bottaro J S Rubin D Ron S A Aaronson 《Science (New York, N.Y.)》1991,251(4989):72-75
An expression cloning strategy was devised to isolate the keratinocyte growth factor (KGF) receptor complementary DNA. NIH/3T3 fibroblasts, which secrete this epithelial cell-specific mitogen, were transfected with a keratinocyte expression complementary DNA library. Among several transformed foci identified, one demonstrated the acquisition of specific high-affinity KGF binding sites. The pattern of binding competition by related fibroblast growth factors (FGFs) indicated that this receptor had high affinity for acidic FGF as well as KGF. The rescued 4.2-kilobase complementary DNA was shown to encode a predicted membrane-spanning tyrosine kinase related to but distinct from the basic FGF receptor. This expression cloning approach may be generally applicable to the isolation of genes that constitute limiting steps in mitogenic signaling pathways. 相似文献
18.
Ken‐ichi YAMANAKA Masahiro KANEDA Yasushi INABA Koji SAITO Kaiyu KUBOTA Miki SAKATANI Satoshi SUGIMURA Kei IMAI Shinya WATANABE Masashi TAKAHASHI 《Animal Science Journal》2011,82(4):523-530
Many observations have been made on cloned embryos and on adult clones by somatic cell nuclear transfer (SCNT), but it is still unclear whether the progeny of cloned animals is presenting normal epigenetic status. Here, in order to accumulate the information for evaluating the normality of cloned cattle, we analyzed the DNA methylation status on satellite I region in blastocysts obtained from cloned cattle. Embryos were produced by artificial insemination (AI) to non‐cloned or cloned dams using semen from non‐cloned or cloned sires. After 7 days of AI, embryos at blastocyst stage were collected by uterine flushing. The DNA methylation levels in embryos obtained by using semen and/or oocytes from cloned cattle were similar to those in in vivo embryos from non‐cloned cattle. In contrast, the DNA methylation levels in SCNT embryos were significantly higher (P < 0.01) than those in in vivo embryos from non‐cloned and cloned cattle, approximately similar to those in somatic cells used as donor cells. Thus, this study provides useful information that epigenetic status may be normal in the progeny of cloned cattle, suggesting the normality of germline cells in cloned cattle. 相似文献
19.
Aoshima H Okita Y Hossain SJ Fukue K Mito M Orihara Y Yokoyama T Yamada M Kumagai A Nagaoka Y Uesato S Hara Y 《Journal of agricultural and food chemistry》2005,53(6):1955-1959
Recently, 3-O-octanoyl-(+)-catechin (OC) was synthesized from (+)-catechin (C) by incorporation of an octanoyl chain into C in the light of (-)-epicatechin gallate (ECg) and (-)-epigallocatechin gallate (EGCg), which are the major polyphenols found in green tea and have strong physiological activities. OC was found to inhibit the response of ionotropic gamma-aminobutyric acid (GABA) receptors (GABA(A) receptors) and Na+/glucose cotransporters expressed in Xenopus oocytes in a noncompetitive manner more strongly than does C. OC also induced a nonspecific membrane current and decreased the membrane potential of the oocyte, and thus death of the oocyte occurred even at lower concentrations than that induced by C or EGCg. Although EGCg produced H2O2 in aqueous solution, OC did not. This newly synthesized catechin derivative OC possibly binds to the lipid membrane more strongly than does C, Ecg, or EGCg and as a result perturbs the membrane structure. 相似文献
20.
Shimamura S Shimizu M Kobayashi M Hirao H Tanaka R Yamane Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(9):935-937
A seven-year-old, female, domestic short hair cat was presented with a history of chronic anorexia. Radiographic examination revealed a large space-occupying calcified mass in the abdominal cavity. The mass was located in pylorus and did not extend into the duodenum and surrounding tissues. Billroth I gastroduodenostomy was conducted to remove the mass. Histopathological examination of the mass showed a lymphoma. Although Recovery following the operation was excellent, the patient showed intermittent vomiting unrelated to feeding. Radiographical examination revealed a megaesophagus, which was assumed to be a complication of the Billroth I procedure, since the condition was not observed before the procedure. 相似文献