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171.
Ishii N Nakahigashi K Baba T Robert M Soga T Kanai A Hirasawa T Naba M Hirai K Hoque A Ho PY Kakazu Y Sugawara K Igarashi S Harada S Masuda T Sugiyama N Togashi T Hasegawa M Takai Y Yugi K Arakawa K Iwata N Toya Y Nakayama Y Nishioka T Shimizu K Mori H Tomita M 《Science (New York, N.Y.)》2007,316(5824):593-597
Analysis of cellular components at multiple levels of biological information can provide valuable functional insights. We performed multiple high-throughput measurements to study the response of Escherichia coli cells to genetic and environmental perturbations. Analysis of metabolic enzyme gene disruptants revealed unexpectedly small changes in messenger RNA and proteins for most disruptants. Overall, metabolite levels were also stable, reflecting the rerouting of fluxes in the metabolic network. In contrast, E. coli actively regulated enzyme levels to maintain a stable metabolic state in response to changes in growth rate. E. coli thus seems to use complementary strategies that result in a metabolic network robust against perturbations. 相似文献
172.
Tomonori Kume Yuka Onozawa Hikaru Komatsu Kenji Tsuruta Yoshinori Shinohara Toshihiro Umebayashi Kyoichi Otsuki 《Forest Ecology and Management》2010
The applicability of sap flux (Fd) measurements to bamboo forests has not been studied. This study was undertaken to establish an optimal and effective design for stand-scale transpiration (E) estimates in a Moso bamboo forest. To this aim, we validated Fd measurements in Moso bamboos in a cut bamboo experiment. In addition, we analyzed how sample sizes affect the reliability of E estimates calculated from Fd and conducting culm area (AS_b). In the cut bamboo experiments, we found that Fd measurement using a 10 mm probe was a valid means of determining the water-use behavior of a Moso bamboo, although a specific correction was needed. Furthermore, we calculated E from stand AS_b (AS_stand) and mean stand Fd (JS). Employing Monte Carlo analysis, we examined potential errors associated with sample size in E, AS_stand, and JS using an original dataset with AS_b and Fd measured for 40 and 16 individuals, respectively. Consequently, we determined the optimal sample size for both AS_stand and JS estimates as 11. The optimal sample sizes for JS were almost the same under different vapor pressure deficit and soil moisture conditions. The optimal sample size for JS at the study site was less than that of a coniferous plantation in the same region probably owing to small individual-to-individual variations in sap flux in the Moso bamboo forest. Our study concludes that sap flux measurements are an applicable technique for assessing water use in Moso bamboo forests. 相似文献
173.
174.
Acetylation of wood was carried out in acetic anhydride only, acetic anhydride/xylene 1:1 (v/v), and acetic anhydride/pyridine 4:1 (v/v) solutions. The antishrink efficiency (ASE), hygroscopic properties, vibrational properties, and bending strength were compared among the three reaction solutions. The ASE was a simple function of weight gain (WG); the equilibrium moisture content at a given WG differed among the reaction solutions. Based on this fact and the results of repeated water soaking and oven-drying tests, it was found that the bulking effect was a major factor, and that decreased hygroscopicity contributes only slightly to the dimensional stabilization by acetylation. The difference in equilibrium moisture content among reaction solutions appears more significant in block samples than wood meal, probably due to the fiber-to-fiber bonds in the former. The tendencies for change in the specific Youngs modulus and the loss tangent differed among reaction solutions, whereas in the static bending test the difference was not marked.Part of this report was represented at the 52nd Annual Meeting of the Japan Wood Research Society, Gifu, April 2002 相似文献
175.
176.
Yosuke Iimura Madoka Yoshizumi Tomonori Sonoki Mikiko Uesugi Kenji Tatsumi Ken-ichi Horiuchi Shinya Kajita Yoshihiro Katayama 《Journal of Wood Science》2007,53(6):541-544
To assess the possible utility of a fungal gene for manganese-dependent peroxidase (MnP) produced by a transgenic plant in
phytoremediation, we transformed hybrid aspen with a chimeric gene for MnP. Our gene construct allowed expression of the gene
for MnP in plants and relatively high MnP activity was detected in the hydroponic medium in which roots of plants that expressed
the transgene had been cultured. Some of our transgenic plants were able to remove bisphenol A from the medium more efficiently
than wild-type plants. Our results demonstrate that, without any modification of the coding sequence, a chimeric gene for
fungal MnP can be expressed in a woody plant, with secretion of active MnP from roots into the rhizosphere. Our strategy suggests
new options using woody plants for phytoremediation. 相似文献
177.
Aito-Inoue M Ohtsuki K Nakamura Y Park EY Iwai K Morimatsu F Sato K 《Journal of agricultural and food chemistry》2006,54(15):5261-5266
For the isolation and detection of food-derived peptides in blood, an approach based on the derivatization of peptides with phenyl isothiocyanate (PITC) was developed. This approach allows hydrophilic peptides to be resolved and specifically detected by reversed-phase (RP) HPLC. For the rapid capturing and clarification of peptides in human plasma, solid-phase extraction by using a mini spin column (5 mmx5 mm) packed with a strong cation exchanger was used. The clarified peptide fraction was further fractionated by size-exclusion chromatography (SEC). The peptides in the SEC fractions were derivatized with PITC, and the derivatives were resolved by RP-HPLC by using an ammonium acetate buffer or a trifluoroacetic acid system. An automatic peptide sequencer based on Edman degradation with a modified program can directly analyze the resolved derivatives. Some synthetic peptides and food-derived peptides in human plasma were successfully isolated and identified by this approach. 相似文献
178.
The wood-based moldings were fabricated by using only citric acid as an adhesive. The mechanical properties, water resistances,
thermal properties and chemical structure were investigated. Wood powder obtained from Acacia mangium was mixed with citric acid under certain weight ratios (0–40 wt%), and each powder mixture was molded using two types of
metal molds at 200°C and 4 MPa for 10 min. The modulus of rupture and the modulus of elasticity values of the wood-based molding
containing 20 wt% citric acid were 35.8 MPa and 5.4 GPa, respectively. The maximum impact strength was 0.94 kJ/m2 with the same citric acid content. The water resistance increased with increasing citric acid content, and the good resistance
to boiling water was also recognized. However, some elution of substances derived from citric acid was observed at high levels
of citric acid, causing a decrease in the thermal properties. The ester linkages were detected by Fourier transform infrared
spectroscopy, indicating that the citric acid reacted with the wood. Our results demonstrated that citric acid brought about
good adhesiveness for fabricating the wood-based molding. 相似文献
179.
Sunaga T Oh N Hosoya K Takagi S Okumura M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(6):745-750
Canine osteoarthritis occurs frequently and causes secondary synovitis. Administration of nonsteroidal anti-inflammatory drugs (NSAIDs) is one of the major therapeutic options for pain management of joint diseases. Tepoxalin has an unique property as an NSAIDs that suppresses both cyclooxygenase and lipoxygenase. The purpose of this study was to evaluate antiproliferative effects of tepoxalin on cultured canine synovial cells. Cytotoxic effects of tepoxalin, carprofen, meloxicam and AA-861 on cultured canine synoviocytes were evaluated by MTT colorimetric assay. Apoptosis was detected by morphological observations with Giemsa or annexin V/Hoechst 33342 staining and by the inhibition of caspase-3 activity with N-Ac-Asp-Glu-Val-Asp-CHO (Ac-DEVD-CHO). Cytotoxic effects of tepoxalin were evident in comparison with the effects of carprofen or meloxicam. The same tendency of cytotoxicity was observed when 5-lipoxygenase was inhibited by AA-861. The morphological findings and contradictory effects of Ac-DEVD-CHO with regard to the cytotoxicity proved the proapoptotic effects of tepoxalin. In conclusion, tepoxalin might control osteoarthritic synovitis by inducing apoptosis in proliferating synoviocytes, while most NSAIDs that selectively inhibit cyclooxygenase-2 most likely would not suppress synovial proliferation. 相似文献
180.
Endo Y Tsuchiya T Sato F Murase H Omura T Korosue K Nambo Y Ishimaru M Wakui Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(8):1079-1081
Prevalence of equine gastric ulcer syndrome in 85 young Thoroughbreds was investigated. The presence of gastric ulcers was confirmed in 27.1% (23/85) of the horses by endoscopic examination. Sixty-two horses without gastric ulcers were allocated randomly to either the treated group (31 horses) or sham-dosed control group (31 horses) in order to investigate the efficacy of omeprazole oral paste in the prevention of gastric ulcers. At the second endoscopic examination conducted after 28 days of administration, only 1 horse in the treated group developed gastric ulcers, while 12 horses developed gastric ulcers in the control group. Based on these data, the efficacy of omeprazole in prevention of equine gastric ulcers in young Thoroughbreds during the training period was confirmed. 相似文献