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101.
Gangliosides of thymuses from rabbit, mouse, rat, calf, and man were analyzed. The ganglioside compositions of the thymuses showed species specificities, and the compositions of the species other than the rabbit were found to be markedly different from that of the rabbit, which contained characteristically substantial amounts of IV3NeuGc-nLc4Cer and VI3NeuGc-nLc6Cer (Iwamori, M. & Nagai, Y. (1981) Biochim. Biophys. Acta 665, 214-220). The inter-species differences in the thymus ganglioside compositions were not remarkable in the 8 mouse and 2 rabbit strains examined. Rabbit thymocytes, but not those of mouse and rat, were lysed with human Hanganutziu-Deicher serum in the presence of guinea pig complement, reflecting the high content of gangliosides containing N-glycolylneuraminic acid in rabbit thymus. As to age-dependent changes of gangliosides in rabbit thymus and spleen, the concentrations gradually decreased with age, while the molar ratio of total gangliosides to total phospholipids was constant in the spleen throughout life and in the thymus at 3, 4, and 6 weeks of age. It was noted that old (180 weeks of age) rabbit thymus, which is occupied largely by fat tissue, still contained a significant amount of neolactoseries gangliosides. 相似文献
102.
A series of fatty acid ethyl esters ranging from C14 to C24 was isolated from a hexane extract of the liverwort Conocephalum conicum, these esters accounted for 77% of the extract. The ethyl esters consisting of even-numbered fatty acids were predominant and ethyl palmitate was the major constituent. 相似文献
103.
Responses of isolated rat iris dilator to some agents and to electrical stimulation were examined. Norepinephrine and epinephrine produced contraction, which was antagonized by 0.03 μM phentolamine. Acetylcholine produced relaxation at low concentrations (1 nM ? 1 μM) as great as 80 % of the resting tone while contraction at high concentrations (≥1 μM). Both responses were suppressed by 0.02 μM atropine and enhanced by 0.03 μM physostigmine. Electrical stimulation at low voltage or low frequency (up to 10 Hz) elicited relaxation while stimulation at high voltage or high frequency (30 Hz) produced contraction. Stimulation with intermediate strength elicited biphasic response. The contraction and relaxation induced by electrical stimulation were abolished by 3 μM phentolamine or by 0.05 μM atropine, respectively. Both phases were abolished by tetrodotoxin (0.3 μM). It is suggested that in the rat the cholinergic relaxation of the dilator may assist the cholinergic contraction of the sphincter (1). The pronounced cholinergic relaxation of nonvascular tissue is to be noted. 相似文献
104.
H Nagai M Kumimoto K Yoshitake T Iwama A Arimura A Koda 《Prostaglandins, leukotrienes, and essential fatty acids》1992,45(3):233-238
The effects were studied of three novel thromboxane A2 (TXA2) receptor antagonists (S-1452, AA-2414 and ONO-3708) on the increase in pulmonary pressure caused by Forssman anaphylaxis in guinea-pigs. Three TXA2 antagonists at doses of between 1 and 10 mg/kg administered orally 1 h before the challenge clearly inhibited the pulmonary pressure increase. At a dose of 10 mg/kg, all three antagonists inhibited the pulmonary pressure increase caused by leukotriene D4 (LTD4) and U-46619, but not that caused by histamine. The decrease in peripheral platelet counts caused by Forssman anaphylaxis was also clearly inhibited by the three TXA2 antagonists. However, the decreased peripheral leukocyte counts were unaffected by the three agents. The decrease in serum complement activity (CH50) was inhibited by S-1452 and AA-2414 at a dose of 10 mg/kg. In bronchoalveolar lavage fluid (BALF), significant increases in eosinophils and neutrophils were observed after Forssman anaphylaxis. Three TXA2 antagonists at a dose of 10 mg/kg (except for AA-2414 on eosinophils) did not affect the changes of leukocyte counts in BALF. Moreover, increases in the TXB2 and 6-keto-PGF1 alpha levels of the BALF brought about by Forssman anaphylaxis were unaffected by the three TXA2 receptor antagonists. Histamine and LTD4 were not changed in the BALF after Forssman anaphylaxis. These results indicate the efficacy of TXA2 receptor antagonists on the increase in pulmonary pressure caused by Forssman anaphylaxis in guinea-pigs by direct antagonism to released TXA2. 相似文献
105.
106.
Chick embryos grown in ex ovo culture by the modified Cornish pasty method reported in Nagai, Lin and Sheng in this issue. 相似文献
107.
108.
Furihata Ryuji Kizuki Jun Yamano Yuya Mizoguchi Yasuhide Nakajima Suguru Nagai Kou Kaneko Yoshiyuki Yamada Koju Suzuki Masahiro Uchiyama Makoto 《Sleep and biological rhythms》2020,18(2):155-157
Sleep and Biological Rhythms - A 39-year-old married woman was referred to a psychiatry outpatient clinic for treatment of major depressive disorder (MDD). The dose of zolpidem she had been taking... 相似文献
109.
A winter geometrid moth, Inurois punctigera, shows sympatric and genetically isolated seasonal populations (i.e. early‐ and late‐winter populations) in the cold regions of Japan, whereas it shows only mid‐winter populations in the warm regions. Variation in adult flight phenology on a large geographic scale along latitudinal environmental gradients has been described, but the phenological variation on a more local scale along altitudinal environmental gradients has not yet been characterized. In the present study, we assessed the flight phenology at high‐ and low‐elevation areas in Mt. Rokko, Hyogo, Japan. First, we revealed that flight period was not disrupted in mid‐winter, even at high‐elevation areas (>660 m) but the population abundance was much lower in high‐elevation areas than in low‐elevation areas. Then, in the following two seasons, we investigated I. punctigera abundance, winter harshness (i.e. winter temperature) and their host plant abundance in nine closely located stations in Mt. Rokko. A generalized linear mixed model analysis indicated a greater effect of winter temperature on I. punctigera abundance compared to available food resources, suggesting that differences in winter harshness among elevation shapes the gradient of I. punctigera abundance along altitude. Our findings suggest that harsh conditions during winter function as selective agents on mid‐winter types of I. punctigera, and this could be involved in the divergence between sympatric early‐ and late‐winter populations of I. punctigera. 相似文献
110.
A Geometry-Based Multiple Testing Correction for Contingency Tables by Truncated Normal Distribution
Basak Tapati Nagashima Kazuhisa Kajimoto Satoshi Kawaguchi Takahisa Tabara Yasuharu Matsuda Fumihiko Yamada Ryo 《Statistics in biosciences》2020,12(1):63-77
Statistics in Biosciences - Inference procedure is a critical step of experimental researches to draw scientific conclusions especially in multiple testing. The false positive rate increases unless... 相似文献