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11.
Kenta Adachi Keiko Ohnishi Takashi Kuramochi Tatsuki Yoshinaga Sei-Ichi Okumura 《Fisheries Science》2014,80(3):445-450
Octopus (Amphioctopus) areolatus is an important marine cephalopod in Japan. We examined its diploid chromosome number, karyotype, and genome size (C value), and performed fluorescence in situ hybridization (FISH) using a vertebrate telomeric probe. The diploid chromosome number was 60 in embryonic cells, with 24 pairs of metacentric chromosomes, four pairs of metacentric/submetacentric chromosomes, and two pairs of submetacentric chromosomes. The mean C value was estimated to be 5.47 pg. From these findings, and those reported previously for other octopus species, we suggest that the factor causing the quantum change of C value in O. (A.) areolatus was genome duplication, and not polyploidy. In telomeric FISH analysis, hybridization signals were clearly observed in the telomeric regions of the chromosomes. This is the first report of FISH analysis of cephalopod chromosomes, and our findings suggest that the telomere sequence of O. (A.) areolatus is (TTAGGG) n , which may allow gene mapping in the future. 相似文献
12.
Scallop aquaculture has grown to become the most successful marine shellfish farming venture in Japan. To ensure long-term
sustainability of scallop production, suitable sites need to be selected. This study was conducted to identify the most suitable
sites for hanging culture of Japanese scallop (Mizuhopecten yessoensis) based on measured biophysical parameters and modeled using geographic information system (GIS) models. Four biophysical
parameters that influence Japanese scallop aquaculture in Funka Bay were selected: sea temperature, food availability (chlorophyll-a), suspended solid, and bathymetry. The SeaWiFS and MODIS images were used to extract most of these parameters. A series of
GIS models was developed to identify suitable sites for scallop culture using a multi-criteria evaluation (MCE) known as weighted
linear combination. Suitability scores were ranked on a scale from 1 (least suitable) to 8 (most suitable), and about 83%
of the total potential area with bottom depths less than 60 m had scores of 7 and 8. The final model outputs were compared
with field verification data and found to be consistent. Local sensitivity analysis was used to test the robustness of the
model output. Based on this analysis, the order of importance of the variables affecting the model was as follows: suspended
solid > chlorophyll-a > sea temperature. 相似文献
13.
Hori Y Kanai K Nakao R Hoshi F Higuchi S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(4):359-366
We developed a novel index to assess left ventricular (LV) relaxation as the ratio of transmitral early diastolic velocity to pulmonary diastolic velocity (E/D ratio). Mixed breed dogs (n=7) were anesthetized and their respiration was controlled. A 3.5-Fr micromanometer-tipped catheter was placed into the left ventricle. Dobutamine (5.0 or 10 microg/kg/min) or esmolol (100 or 500 microg/kg/min) was administered via the cephalic vein. The transmitral flow (TMF) and pulmonary venous flow (PVF) were recorded using transthoracic echocardiography from the apical long-axis view. The heart rate, systolic LV pressure, +dP/dt, and -dP/dt were significantly elevated by dobutamine, but significantly reduced by esmolol. Dobutamine significantly decreased tau, whereas esmolol significantly increased tau. The TMF-derived E and PVF-derived D wave velocities increased significantly with dobutamine, but decreased significantly with esmolol. A significant correlation was detected between the E and D wave velocities (r=0.92). Consequently, the E/D ratio was decreased significantly with dobutamine, and increased significantly with esmolol. Furthermore, the E/D ratio was significantly correlated with -dP/dt (r= -0.64) and tau (r=0.84). Our results suggest that the E/D ratio reflects LV relaxation, and may potentially provide further information on LV relaxation. 相似文献
14.
Zahida Iqbal Syuntaro Hiradate Akio Noda Sei-Ichi Isojima Yoshiharu Fujii 《Weed Biology and Management》2002,2(2):110-115
The allelopathic potential of buckwheat ( Fagopyrum esculentum ) was investigated. Field study showed that living buckwheat reduced weed biomass compared with plots without buckwheat. Laboratory study revealed that root exudates suppressed root and shoot growth of weeds and reduced weed dry weight. Sequential partitioning of the aqueous ethanolic extract of the aerial parts of buckwheat showed that the chloroform extract caused an 80% reduction in radicle elongation of lettuce seedlings at a concentration of less than 100 p.p.m. Fagomine, 4-piperidone and 2-piperidinemethanol were isolated and identified by 1 H and 13 C nuclear magnetic resonance from the chloroform extract. These compounds caused a 50% inhibition of radicle elongation in lettuce seedlings at concentrations of less than 100 p.p.m. These results suggest that compounds 1, 2, and 3 might act as allelochemicals and affect the growth or germination of different plant species. 相似文献