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1.
We investigated the effects of near-infrared irradiation on the photoconversion of Chenopodium album water-soluble chlorophyll-binding protein (CaWSCP) in the presence of sodium hydrosulfite and found a further photoconversion from CP742 to CP763, a novel form of CaWSCP. Interestingly, one-third of the absorption peak at 668 nm was recovered in CP763, but re-irradiation under oxidative conditions eliminated the photo convertibility of CaWSCP. 相似文献
2.
3.
Yasushi Harada 《Journal of Ethology》1989,7(1):17-25
A theory on the evolution of human primary sex ratio is proposed. Effects of parental preference for sons, reflected in birth
control based on offspring sex ratio and female biased infanticide, on the evolution of primary sex ratio are analyzed. Both
are shown to select for female bias in primary sex ratio. The gene-culture coevolution of female infanticide and primary sex
ratio is also studied and it is shown that female infanticide develops more in societies in which the father plays a more
important role in the transmission of culture than the mother does. 相似文献
4.
5.
Isamu Tanaka Akio Horie Joji Haratake Yasushi Kodama Kenzaburo Tsuchiya 《Biological trace element research》1988,16(1):19-26
There are few inhalation studies of nickel carcinogenesis. In this study, Wistar male rats were exposed to green nickel oxide
(NiO(G)) aerosols (mass median aerodynamic diameter, 0.6 μm) for 7 h/d, 5 d/wk for up to 12 mo. The average exposure concentration
was controlled at 0.3 and 1.2 mg/m3 during the exposure. For histopathological examination and measurement of the nickel concentration in rat organs, the rats
were sacrificed at 3, 6, and 12 mo of exposure and 8 mo clearance period following 12 mo of exposure.
The nickel content in rat lungs that was observed up to 2.6 mg after 12 mo exposure, was proportional to the exposure concentration
during the exposure. The clearance of the nickel from the lungs was very slow and the biological half time was determined
7.7 mo.
Although the rats were exposed continuously to NiO(G), for 12 mo and kept for 8 mo clearance period, there were no malignant
tumors in any of the exposed animals. 相似文献
6.
Masaki Fujimura Yasushi Miyake Kohhei Uotani Kazunori Kanamori Tamotsu Matsuda 《Prostaglandins & other lipid mediators》1988,35(3)
Effect of a thromboxane synthetase inhibitor (OKY-046) on bronchoconstriction induced by aerosol leukotriene C4 and histamine was studied in anesthetized, artificially ventilated guinea pigs in order to examine whether secondary release of thromboxane A2 is produced by aerosol leukotriene C4 or not. 0.01–1.0μg/ml of leukotriene C4 and 12.5–400μg/ml of histamine inhaled from ultrasonic nebulizer developed for small animals caused dose-dependent increase of pressure at airway opening (Pao) which is considered to be an index representing bronchial response. Pretreatment of the animals with intravenous OKY-046 (100mg/kg) significantly reduced the airway responses produced by inhalation of 0.1, 0.33 and 1.0μg/ml of leukotriene C4, while the pretreatment did not affect the histamine dose-response curve. Based on these findings and previous reports (6, 7), it is suggested that aerosol leukotriene C4 activates arachidonate cyclooxygenase pathway including thromboxane A2 synthesis and the released cyclooxygenase products have bronchodilating effect as a whole 相似文献
7.
8.
Takayuki Hoson Seiichiro Kamisaka Yoshio Masuda Masamichi Yamashita 《Journal of plant research》1992,105(1):53-70
We developed a three-dimensional (3-D) clinostat to simulate a microgravity environment and studied the changes in plant growth processes under this condition. The rate of germination of cress (Lepidium sativum), maize (Zea mays), rice (Oryza sativa), pea (Pisum sativum), or azuki bean (Vigna angularis) was not affected on the clinostat. The clinostat rotation did not influence the growth rate of their roots or shoots, except for a slight promotion of growth in azuki roots and epicotyls. On the contrary, the direction of growth of plant organs clearly changed on the 3-D clinostat. On the surface of the earth, roots grow downward while shoots upward in parallel to the gravity vector. On the 3-D clinostat, roots of cress elongated along the direction of the tip of root primordia after having changed the direction continuously. Rice roots also grew parallel to the direction of the tip of root primordia. On the other hand, roots of maize, pea, and azuki bean grew in a random fashion. The direction of growth of shoots was more controlled even on the 3-D clinostat. In a front view of embryos, shoots grew mostly along the direction of the tip of primordia. In a side view, rice coleoptiles showed an adaxial (toward the caryopsis) while coleoptiles of maize and epicotyls of pea and azuki bean an abaxial curvature. The curvature of shoots became larger with their growth. Such an autotropism may have an important role in regulation of life cycle of higher plants under a microgravity environment. 相似文献
9.
Organic anion transport study in mutant rats with autosomal recessive conjugated hyperbilirubinemia 总被引:2,自引:0,他引:2
H Kurisu K Kamisaka T Koyo S Yamasuge H Igarashi H Maezawa T Uesugi O Tagaya 《Life sciences》1991,49(14):1003-1011
The EHBR is a mutant rat strain with congenital conjugated hyperbilirubinemia bred from a Sprague-Dawley rat. Transport of conjugated bilirubin, indocyanine green, and tetrabromosulfophtalein from liver to bile is severely impaired in these rats. Serum bilirubin amounts to 6.0 +/- 0.05 mg/dl (n = 4) in adult rats, with 97% conjugates. The bile flow is reduced to about 65% of the control group, whereas total bile acid in 10-min bile samples is similar. Liver histology of 10 week-old rats revealed neither intracellular pigmentation nor architectural abnormalities. 相似文献
10.
Kah-Siew Tan Takayuki Hoson Yoshio Masuda Seiichiro Kamisaka 《Physiologia plantarum》1991,83(3):397-403
Rice ( Oryza sativa L. cv. Sasanishiki) coleoptiles grown under water achieved greater length than those grown either in air or under water with constant air bubbling. The extensibility of cell walls in coleoptiles grown under water was larger than that in the other treatments. Per unit length of the coleoptile, the content of ferulic and diferulic acids ester-linked to hemicelluloses was higher in air and bubbling type coleoptiles than in water type ones. The extensibility of the coleoptile cell walls correlated with the content of diferulic acids per unit length and per hemicellulose, suggesting that the enhancement of the formation of diferulic acid bridges in hemicelluloses in air or under water with air bubbling makes the cell walls mechanically rigid; thereby inhibiting cell elongation in rice coleoptiles. In addition, the ratio of diferulic acid to ferulic acid was almost constant irrespective of coleoptile age, zone and growth conditions, suggesting that the feruloylation of hemicelluloses is rate-limiting in the formation of diferulic acid bridges in the cell walls of rice coleoptiles. 相似文献