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51.
Yoshida K Hishida A Iida O Hosokawa K Kawabata J 《Journal of agricultural and food chemistry》2008,56(12):4367-4371
In the screening experiments for rat intestinal alpha-glucosidase inhibitors in 218 plants cultivated in the Japanese temperate region, potent maltase-inhibiting activity was found in the extract of flowers of Spiraea cantoniensis. The enzyme assay guided fractionation of the extract led to the isolation of three flavonol caffeoylglycosides, quercetin 3- O-(6- O-caffeoyl)-beta-galactoside ( 1), kaempferol 3- O-(6- O-caffeoyl)-beta-galactoside ( 2), and kaempferol 3- O-(6- O-caffeoyl)-beta-glucoside ( 3), as rat intestinal maltase inhibitors. This is the first report on the alpha-glucosidase-inhibitory activity of those flavonol caffeoylglycosides. Comparison in the activity of the isolates indicated the importance of caffeoyl substructures in the molecule for the alpha-glucosidase-inhibiting activity. The relatively high contents of the active isolates in the plant suggest that S. cantoniensis could be physiologically useful for treatment of diabetes. 相似文献
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53.
Cyprinid herpesvirus 3 (CyHV-3), which causes a lethal disease in common carp, Cyprinus carpio L., and koi, C. carpio koi , first occurred in Lake Biwa, Japan in 2004. To elucidate distribution of CyHV-3 in a wild common carp population, we conducted a PCR survey of CyHV-3 among such fish in Lake Biwa in 2006. Only 6% (1/18) of the common carp smaller than 300 mm were positive with PCR, whereas 31% (18/58) of fish larger than 300 mm were positive. To evaluate their past exposure to CyHV-3 infection based on the presence of antibodies, we also measured the levels of serum anti-CyHV-3 antibodies in the carp, using an enzyme-linked immunosorbent assay. None (0/26) of the fish smaller than 300 mm was positive for the antibodies, whereas 54% (33/61) of fish larger than 300 mm were positive. Of the antibody-positive individuals, 44% (14/32) were also positive by PCR strongly suggesting that wild common carp that survived infection become CyHV-3 carriers. Five individuals were positive by PCR but negative for antibodies indicating that their infection with CyHV-3 had occurred recently. These results suggest that transmission of CyHV-3 from carriers to naïve common carp is still occurring in Lake Biwa. 相似文献
54.
T Nakamura S Yoshino E Iida Y Wakao M Muto M Takahashi 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1990,52(2):285-292
Using adult mongrel dogs, experiments were performed to elucidate the relationship between the changes in the myocardial oxygen tension (PmO2) in anoxia and disturbances of cardiac function. Dogs, forced to inspire 100% N2, suffered from a respiratory arrest after 5 min, and developed acute anoxia. However, by 100% O2 inhalation 2 min after the onset of the respiratory arrest, the anoxia rapidly resolved. The arterial oxygen tension (PaO2), left intra ventricular oxygen tension (PLVO2) and PmO2 showed the most pronounced fall 2 min after the respiratory arrest induced by N2 inhalation. The arterial carbon deoxide tension (PaCO2) decreased until the respiratory arrest, after which it started to rise. When inhalation of 100% O2 was initiated at the anoxia, the PaO2, PLVO2 and PmO2 recovered within 1 min followed by a rise beyond the baseline value. Left ventricular end-diastolic pressure (LVEDP), left atrial mean pressure (LAm), left ventricular systolic pressure (LVSP), aortic mean pressure (Aom), maximum rate of force development by left ventricle (LVmax.dp/dt), total peripheral resistance (TPR), cardiac output (CO) and heart rate (HR) were measured. At the onset of anoxia, these parameters decreased sharply. When inhalation of 100% O2 was initiated within 2 min of the respiratory arrest, these disturbances of cardiac function recovered rapidly. The fall of PmO2 plays an important role in the impairment of cardiac function. 相似文献
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56.
Fukuda S Iida H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(7):755-760
Age-related changes in bone mineral density (BMD) and cross-sectional area and bone strength index (SSI) of the femur, tibia, humerus, and first lumbar vertebra in female Wistar (WM/MsNrs) rats were examined by a quantitative computed tomography (pQCT) method. One hundred and sixteen virgin female Wistar (WM/MsNrs) rats aged 2-33 months were used. The data indicate that the total BMD values of metaphyses and diaphyses of long bones increased until 12 months, then decreased to a varying degree depending on the bone after 15-24 months, but the values of cortical and trabecular BMD with age were not always similar to the total BMD value. Nevertheless, the values for cross-sectional area and SSI in the long bones increased regardless of the total BMD decrease with age, indicating that this increase might have been due to a characteristic of the modeling pattern in rats. The total and cortical BMD values in the first lumbar vertebra decreased after 18 months, and SSI did after 15 months. The data obtained in this study were compared with those obtained from males in a previous study. In conclusion, it was indicated that in this strain the rats over 12 months with the highest total BMD values in the femur and tibia, and before the onset of various tumors, are useful as a model animal for osteoporosis experiments and observation of senile bone change. 相似文献
57.
Fukui Y Togawa M Abe N Takano Y Asada M Okada A Iida K Ishikawa H Ohsumi S 《The Journal of reproduction and development》2004,50(1):147-154
The object of the present study was to investigate the validation of the sperm quality analyzer (SQA) and the hypo-osmotic swelling (HOS) test with standard sperm analysis methods in frozen-thawed ram and minke whale spermatozoa. In rams, highly significant correlations were observed in the percentage of motile spermatozoa (P<0.01) and sperm concentration (P<0.01) between the standard and SQA methods. But, the percentage of morphologically normal spermatozoa did not significantly correlate between the standard and SQA methods. The percentages of swollen spermatozoa at 15 minutes by the HOS test were significantly correlated with the motility by the standard (P<0.05) and by the SQA (P<0.05) methods. For minke whale spermatozoa, the SVI (sperm viability index) values by the standard method were significantly (P<0.001) correlated with the sperm motility index (SMI) values by SQA. The percentage of motile spermatozoa was also significantly correlated (P<0.01) with the motility measured by SQA. Using different hypo-osmotic solutions and incubation times, the HOS test with 25, 100 and 150 mOsM did not show significant variations. Motility observed by the standard method and the percentage of swollen spermatozoa were significantly correlated (P<0.05). These results indicate that the SQA and HOS test can be utilized to assess the post-thawing motility of ram and minke whale spermatozoa, and that the SQA and HOS test values are significantly correlated in ram spermatozoa. However, sperm concentration and morphologically normal spermatozoa are not assessed accurately by SQA in minke whales. 相似文献
58.
Iida K Kobayashi N Kohno H Miyamoto A Fukui Y 《The Journal of reproduction and development》2004,50(1):63-69
The aim of the present study was to compare three methods of estrus synchronization in ewes during the non-breeding season. Forty-two ewes were randomly grouped for three treatments with different intravaginal devices for 12 days: Group A) CIDR, Group B) Self-made P sponge, Group C) MAP (medroxyprogesterone acetate) cream sponge. Furthermore, all groups were divided into two treatments with (R) or without ram presence to examine the "ram effect". Blood was collected from all treated ewes, and progesterone (P(4)), estradiol 17-beta (E(2)) and luteinizing hormone (LH) concentrations were measured by enzyme-immunoassay. All ewes showed estrus behavior between Day 0 to 3 after device removal, and the mean onset times of their estrus were 23.0, 33.0 and 21.0 h for Groups AR, BR and CR, respectively. On Day 5 as examined by laparoscopy, the ovulation rates (and number of ovulated ewes) were 1.45 (11/11), 1.25 (12/14) and 1.21 (14/14) for Groups A, B and C, respectively. In Group C, the time to LH surge was significantly (P<0.05) later (32.4 h) than those in Groups A (27.0 h) and B (25.5 h). Ram presence did not affect the number of ovulated ewes, ovulation rate or time to LH surge. The ram introduction group had significantly (P<0.05) lower E(2) concentrations during the period from 0 h to 36 h than the groups without ram presence. These results suggest that the self-made P sponge or MAP cream sponge was effective as well as CIDR, and ram introduction was not necessary, for induction of estrus and ovulation during the non-breeding season. 相似文献
59.
Michihisa Iida Donghyeon Kang Mitsuru Taniwaki Mutsumi Tanaka Mikio Umeda 《Computers and Electronics in Agriculture》2008,63(1):73-robotics
A hexapod robot was developed to explore an agricultural field and gather agronomical information such as soil nutrients and plant growth. In addition, a sensor device for the robot to track a gas source was developed. The sensor device consisted of a CO2 gas sensor and an anemoscope. The gas sensor detected the concentration of CO2 in the surroundings, and the anemoscope indicated the upwind direction from the robot. An indoor test was conducted during which the hexapod robot tracked windward direction using the sensor device. According to the results, the hexapod robot with the sensor device successfully localized a CO2 source that was in the upwind direction. The robot paused on the spot under windless conditions, and walked windward as soon as the wind started blowing again. 相似文献