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121.
Hideaki Tanoue Teruhisa Komatsu Takurou Tsujino Ippei Suzuki Masayoshi Watanabe Hideki Goto Nobuyuki Miyazaki 《Fisheries Science》2012,78(3):533-538
The feeding events of wild animals have been widely researched in recent decades. The use of invasive methods to determine
stomach contents in which the fish is killed can, however, be considered to be unjustifiable in the case of an endangered
fish, such as the Japanese late. Here, we report on a method that can be used to verify feeding events of a fish species without
the need for killing the fish through the use of a high-speed video camera and a three-axis micro-acceleration data-logger.
High-quality images obtained by the video showed that the fish opens its mouth with a quick downward movement of the mandibles
and ingests prey via suction feeding. The movement of the mandibles was also simultaneously recorded by changes in the three-axis
accelerations obtained by the logger attached to the dorsum. We attached the logger with an automatic release system to the
dorsum of one captive Japanese lates and two wild fish together with an acoustic transmitter and then released the fish in
the Shimanto River in Japan. After retrieving the logger, the movement records of the fish obtained by the three-axis accelerometer
showed the same pattern of feeding events as those in captivity. A total of 13 feeding events at night and five during the
daytime were obtained for the three fish during a total 129.7 h of recording. 相似文献
122.
Chotichayapong C Wiengsamut K Chanthai S Sattayasai N Tamiya T Kanzawa N Tsuchiya T 《Fish physiology and biochemistry》2012,38(5):1533-1543
Myoglobin from Asian swamp eel Monopterus albus was purified from fish muscle using salt fractionation followed by column chromatography and molecular filtration. The purified Mb of 0.68?mg/g wet weight of muscle was determined for its molecular mass by MALDI-TOF-MS to be 15,525.18?Da. Using isoelectric focusing technique, the purified Mb showed two derivatives with pI of 6.40 and 7.12. Six peptide fragments of this protein identified by LC-MS/MS were homologous to Mbs of sea raven Hemitripterus americanus, yellowfin tuna Thunnus albacores, blue marlin Makaira nigicans, common carp Cyprinus carpio, and goldfish Carassius auratus. According to the Mb denaturation, the swamp eel Mb had thermal stability higher than walking catfish Clarias batrachus Mb and striped catfish Pangasius hypophthalmus Mb, between 30 and 60?(°)C. For the thermal stability of Mb, the swamp eel Mb showed a biphasic behavior due to the O(2) dissociation and the heme orientation disorder, with the lowest increase in both Kd(f) and Kd(s). The thermal sensitivity of swamp eel Mb was lower than those of the other Mbs for both of fast and slow reaction stages. These results suggest that the swamp eel Mb globin structure is thermally stable, which is consistent with heat-tolerant behavior of the swamp eel particularly in drought habitat. 相似文献
123.
Atsuya Yamashita Yuusuke Fujimoto Mayumi Tamaki Andi Setiawan Tomohisa Tanaka Kaori Okuyama-Dobashi Hirotake Kasai Koichi Watashi Takaji Wakita Masaaki Toyama Masanori Baba Nicole J. de Voogd Shinya Maekawa Nobuyuki Enomoto Junichi Tanaka Kohji Moriishi 《Marine drugs》2015,13(11):6759-6773
The current treatments of chronic hepatitis B (CHB) face a limited choice of vaccine, antibody and antiviral agents. The development of additional antiviral agents is still needed for improvement of CHB therapy. In this study, we established a screening system in order to identify compounds inhibiting the core promoter activity of hepatitis B virus (HBV). We prepared 80 extracts of marine organisms from the coral reefs of Indonesia and screened them by using this system. Eventually, two extracts showed high inhibitory activity (>95%) and low cytotoxicity (66% to 77%). Solvent fractionation, column chromatography and NMR analysis revealed that 3,5-dibromo-2-(2,4-dibromophenoxy)-phenol (compound 1) and 3,4,5-tribromo-2-(2,4-dibromophenoxy)-phenol (compound 2), which are classified as polybrominated diphenyl ethers (PBDEs), were identified as anti-HBV agents in the extracts. Compounds 1 and 2 inhibited HBV core promoter activity as well as HBV production from HepG2.2.15.7 cells in a dose-dependent manner. The EC50 values of compounds 1 and 2 were 0.23 and 0.80 µM, respectively, while selectivity indexes of compound 1 and 2 were 18.2 and 12.8, respectively. These results suggest that our cell-based HBV core promoter assay system is useful to determine anti-HBV compounds, and that two PBDE compounds are expected to be candidates of lead compounds for the development of anti-HBV drugs. 相似文献
124.
125.
126.
Molla Rahman Shaibur Nobuyuki Kitajima Reiko Sugawara Toshihito Kondo Shah Alam S. M. Imamul Huq Shigenao Kawai 《Water, air, and soil pollution》2008,189(1-4):279-289
In this study, NO2 and SO2 levels during a specific winter episode in the city of Istanbul were researched with regard to the respective impact of weather conditions. The city under study has the largest population and is one of the most polluted cities of Turkey. Furthermore, Istanbul is vulnerable to trans-boundary transport of air pollutants from Europe, because its location is on the eastern end of the Continent, where westerly winds prevail. However, there has neither been any comprehensive study nor any regulation to fix and solve the air quality problem in the city so far. A framework was prepared to model air quality using MM5 for meteorological modeling and CMAQ for transport and chemistry modeling. This study was supported by the tracer and the trajectory investigations over the area of interest. The model results underestimated the concentration of air pollutants over Istanbul as expected. But, in spite of the coarse emission inventory, the similarity of the time series between the model and observation values during the simulation period is very encouraging for future studies. That is to say, the tracer and the trajectory studies indicated that trans-boundary sources are responsible for the poor air quality of Istanbul under specific weather conditions. It must be pointed out, though, that a high-resolution national emission inventory is needed to get more accurate results. 相似文献
127.
Shoji Nakagawa Nobuyuki Okajima Tetsuo Kitahaba Keiichiro Nishimura Toshio Fujita Minoru Nakajima 《Pesticide biochemistry and physiology》1982,17(3):243-258
A number of substituted benzyl (1R)-trans-chrysanthemates and related compounds were synthesized. Their symptomatic activities in terms of levels which induce convulsions as well as cause death in American cockroaches were determined by injection with and without application of synergists as inhibitors of metabolism. The neuroexcitatory and neuroblocking activities were also determined in terms of minimum effective concentrations to induce repetitive train of impulses and conduction blockage, respectively, to central nerve cords excised from the cockroaches and immersed in Ringer's solution. Correlations between symptomatic and neurophysiological activities were analyzed quantitatively with the aid of molecular hydrophobicity parameter and regression analysis. Each symptomatic activity from which the effect of metabolism is eliminated was found to be analyzable by means of a linear combination of indices for two types of neurophysiological activity when the transport factor is separated by using the hydrophobicity parameter. A closer correlation was found between neuroblocking activity and the “convulsive” effect than between neuroexcitatory activity and the “convulsive” effect, whereas both neurophysiological effects operate together on the cockroaches resulting in paralysis and death. 相似文献
128.
Tsutsui T Tezuka T Mikasa Y Sugisawa H Kirihara N Hori T Kawakami E 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(3):307-312
Cooled canine semen solutions for storage were investigated with three stock solutions: egg yolk-citrate-glycine-glucose solution, egg yolk Tris-fructose citrate solution (EYT-FC), and egg yolk sodium citrate dihydrate solution (EYCD). For the control group, the second fraction of semen was examined. Nine male beagles and 37 female (47 experimental cases) beagles for artificial insemination (AI) were used. The qualities of semen stored at 4 degrees C deteriorated earlier in the control and EYCD groups. In the other two groups, sperm motility was 60% or higher after storage for 6 days and 20% or higher after storage for 12 days. On a comparison of these two groups, the sperm motility and viability were slightly higher in the EYT-FC group. A high conception rate was obtained by AI using semen stored at a low temperature for a maximum of two days in the control group and four days in the EYT-FC group. 相似文献
129.
Nobuyuki Okajima Isao Aoki Takashi Kuragano Yoshiyuki Okada 《Pest management science》1991,31(1):91-128
A series of 2-(1,3-dimethyl-4-substituted-5-pyrazolyl)sulfonylimino-5,7-disubstituted-2H-1,2,4-thiadiazolo[2,3-a]pyrimidines was synthesized and tested for herbicidal effects. The compounds showed potent activity and improved selectivity to rice when compared with analogous sulfonylurea derivatives. 相似文献
130.