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61.
62.
Masao Kawai Kenji Yoshiba Shigeru Ando Shigeru Azuma 《Primates; journal of primatology》1968,9(1-2):1-12
The social behavior pattern of a solitary male at Koshima was studied by means of radio-telemetry. The relationship between the solitary males and the troop was estimated from radio-tracking data of the former's location and movement, and by direct observation of the latter at each corresponding hour.For most of day, the solitary male stayed within a distance of about 20 to 150 m from the central part of the troop, occasionally approaching it. His movement also was synchronized with that of the troop. For two nights, the solitary male slept at places which were about 200 m from the sleeping sites of the troop and faced them across the beach. The relationship between the solitary male and the troop did not seem to be strongly antagonistic.It can be assumed that the solitary male was moving according to certain pre-determined relationships or social contacts with the troop. The example of this solitary male shows the existence of the solitary male that follows and maintains contact with the troop, even outside the copulatory season.This study was sponsored by Scientific Research Grant No. 91620 of the Ministry of Education to the Japan Monkey Centre. 相似文献
63.
Chao-Wu Xiao Carla M. Wood Eleonora Swist Reiko Nagasaka Kurtis Sarafin Claude Gagnon Lois Fernandez Sylvie Faucher Hong-Xing Wu Laura Kenney Walisundera M. N. Ratnayake 《PloS one》2016,11(1)
Objectives
This study compared cardio-metabolic disease risk factors and their associations with serum vitamin D and omega-3 status in South Asian (SAC) and White Canadians (WC) living in Canada’s capital region.Methods
Fasting blood samples were taken from 235 SAC and 279 WC aged 20 to 79 years in Ottawa, and 22 risk factors were measured.Results
SAC men and women had significantly higher fasting glucose, insulin, homeostasis model assessment for insulin resistance (HOMA-IR), apolipoprotein B (ApoB), ratios of total (TC) to HDL cholesterol (HDLC) and ApoB to ApoA1, leptin, E-selectin, P-selectin, ICAM-1 and omega-3 (p < 0.05), but lower HDLC, ApoA1, vitamin D levels than WC (p < 0.05). SAC women had higher CRP and VEGF than WC women. Adequate (50–74.9 nmol/L) or optimal (≥ 75 nmol/L) levels of 25(OH)D were associated with lower BMI, glucose, insulin, HOMA-IR, TG, TC, low density lipoprotein cholesterol (LDLC), ApoB/ApoA1 ratio, CRP, leptin, and higher HDLC, ApoA1, omega-3 index, L-selectin levels in WC, but not in SAC. Intermediate (>4%-<8%) or high (≥ 8%) levels of omega-3 indices were related to lower E-selectin, P-selectin, ICAM-1 and higher HDLC, 25(OH)D levels in WC, but not in SAC. The BMIs of ≤ 25 kg/m2 were related to lower LDLC, ApoB, VEGF, creatinine and higher 25(OH)D in WC, but not in SAC.Conclusions
The associations of vitamin D, omega-3 status, BMI and risk factors were more profound in the WC than SAC. Compared to WC, vitamin D status and omega-3 index may not be good predictive risk factors for the prevalence of CVD and diabetes in SAC. 相似文献64.
65.
Hiroshi Hayakawa Kanji Ishizaki Masao Inoue Takashi Yagi Mutsuo Sekiguchi Hiraku Takebe 《Mutation research》1981,80(2)
DNA-repair characteristics of xeroderma pigmentosum belonging to complementation group F were investigated. The cells exhibited an intermediate level of repair as measured in terms of (1) disappearance of T4 endonuclease-V-susceptible sites from DNA, (2) formation of ultraviolet-induced strand breaks in DNA, and (3) ultraviolet-induced unscheduled DNA synthesis during post-irradiation incubation. The impaired ability of XP3YO to perform unscheduled DNA synthesis was restored, to half the normal level, by the concomitant treatment with T4 endonuclease V and ultraviolet-inactivated Sendai virus. It is suggested that xeroderma pigmentosum cells of group F may be defective, at least in part, in the incision step of excision repair. 相似文献
66.
A New System for Stringent, High-Titer Vesicular Stomatitis Virus G Protein-Pseudotyped Retrovirus Vector Induction by Introduction of Cre Recombinase into Stable Prepackaging Cell Lines 总被引:1,自引:2,他引:1 下载免费PDF全文
67.
68.
Shin-ichiro Katsuda Hidefumi Waki Masao Yamasaki Tadanori Nagayama Hirotaka O-Ishi Kiyoaki Katahira Noboru Machida Masamitsu Hasegawa Tsuyoshi Shimizu 《Experimental Animals》2002,51(1):83-93
Postnatal changes in the rheological properties of the aortic wall were investigated in relation to morphological development of the wall in Sprague-Dawley (SD) rats at 3, 8 and 20 weeks old. The mechanical tensile characteristics of the longitudinal wall strip excised from the proximal thoracic aorta were assessed with stress-strain and stress-relaxation tests. Wall tension in the low and medium strain ranges was significantly lower in 3-week-old rats than in 8-week-old rats and in 8-week-old rats than in 20-week-old rats. Wall stress was significantly lower in 3-week-old rats than in 8- and 20-week-old rats mainly in the medium strain range, but was significantly greater in 3-week-old rats than in 8- and 20-week-old rats in the high strain range. The value of incremental elastic modulus at 3 weeks old was significantly smaller than that at 8 and 20 weeks old at a strain of 0.25 and significantly larger than that at 8 and 20 weeks old at a strain of 0.50. The value of relaxation strength at 5 min after the stretching was significantly greater at 3 weeks old than that at 8 and 20 weeks old. The wall was viscoelastic in the low and medium strain ranges at 3 weeks though large wall stress was generated in the high strain range. Histological investigation revealed that the smooth muscle layer, fine elastin fiber connecting thick elastin fibers and wall thickness were thin at 3 weeks old in comparison with those at 8 and 20 weeks old, though there was no significant difference in number of nuclei of the smooth muscle cells among the three age groups. Changes in the tensile characteristics of the wall reflected well those of the microstructure of the wall with growth. The rheological properties and microstructure of the aortic wall were close to maturation at 8 weeks in SD rats. 相似文献
69.
Hideki Endo Hiroyuki Sasaki Yoshihiro Hayashi Evageny A. Petrov Masao Amano Nobuyuki Miyazaki 《Marine Mammal Science》1998,14(4):778-788
This study was performed to determine if, as expected, the enlarged eye of the Baikal seal ( Phoca sibirica ) has an influence on the form and function of the skull and facial muscles. Macroscopic observation of these muscles demonstrated that the M. orbicularis oculi expands around the palpebral fissure and that some facial muscles attach and insert in the M. orbicularis oculi , possibly supporting M. orbicularis oculi function. We suggest that these muscles move the eye and palpebral area and constitute a morphological and synergistic facial muscle complex system. Further, the development of the M. rectus lateralis around the sclera of the eye indicates that this muscle is also involved in eye movement. 相似文献
70.
The malarial parasite has two hosts in its life cycle, a vertebrate and a mosquito. We report here that malarial invasion into these hosts is mediated by a protein, designated cell-traversal protein for ookinetes and sporozoites (CelTOS), which is localized to micronemes that are organelles for parasite invasive motility. Targeted disruption of the CelTOS gene in Plasmodium berghei reduced parasite infectivity in the mosquito host approximately 200-fold. The disruption also reduced the sporozoite infectivity in the liver and almost abolished its cell-passage ability. Liver infectivity was restored in Kupffer cell-depleted rats, indicating that CelTOS is necessary for sporozoite passage from the circulatory system to hepatocytes through the liver sinusoidal cell layer. Electron microscopic analysis revealed that celtos-disrupted ookinetes invade the midgut epithelial cell by rupturing the cell membrane, but then fail to cross the cell, indicating that CelTOS is necessary for migration through the cytoplasm. These results suggest that conserved cell-passage mechanisms are used by both sporozoites and ookinetes to breach host cellular barriers. Elucidation of these mechanisms might lead to novel antimalarial strategies to block parasite's transmission. 相似文献