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71.
72.
The analgesic actions of some synthetically prepared peptides having the Tyr-D-Arg unit at the N terminal portion of met- and leu-enkephalin were measured by the intra-cisternal injection method in mice. Among them, Tyr-D-Arg-Gly-Phe (DR-4) induced the most potent naloxone-reversible analgesia and was also effective by s.c. injection. DR-4 showed the good affinity to mu-receptor, and the resistance to the enzymatic degradation. 相似文献
73.
Junichi Kitajima Tetsuya Komori Toshio Kawasaki Hans-rolf Schulten 《Phytochemistry》1982,21(1):187-192
From the aerial parts of Fritillaria thunbergii, three glycosidal Solanum alkaloids (basic steroid saponins) were isolated together with minor 相似文献
74.
Pui-Wah Lau Cynthia Hung Kayoko Minakata Elias Schwartz Toshio Asakura 《生物化学与生物物理学报:生物膜》1979,552(3):499-508
A maleimide spin label (N-(1-oxyl-2,2,5,5-tetramethylpyrrolidinyl)-maleimide) was reacted with oxyhemoglobin-free cell stromata of normal and sickle cells. The EPR spectrum of spin-labeled red cell membranes showed that the spin labels are attached to at least two different binding sites. There was a major signal, A, which characterized a strongly immobilized environment and a minor signal, B, which characterized a weakly immobilized environment. Quantitative EPR measurements using equal amounts of Hb AA and Hb SS red blood cells demonstrated that Hb SS red cell membranes had an approximately four times higher EPR signal intensity than Hb AA red cell membranes ((7.98 ± 1.14) · 105 and (2.2 ± 1.2) · 105 spin labels/cell, respectively). Moreover, the ratio of signal intensities A and B are different in these cells. Comparative spectrophotometric studies of membrane-associated denatured hemoglobins of Hb AA and Hb SS red cell membranes suggested that the EPR signal A is derived from spin labels attached to membrane-associated denatured hemoglobin, while signal B is mainly from spin labels attached to membrane-associated denatured hemoglobin, while signal B is mainly from spin labels attached to membranes. The combination of EPR spectrum of Hb AA membranes pretreated with N-ethyl-maleimide and that of spin-labeled precipitated hemoglobin further strengthened this conclusion. 相似文献
75.
76.
77.
The quantity of organic acids ( lactic acid, acetic acid, propionic acid and butyric acid ) in the content of the gastrointestinal tract of germ-free and conventional rats and the effects of the organic acid on the motility of the gastrointestinal tract of rats were investigated.Organic acids were detected only in the gastrointestinal contents of conventional rats but not in those of germ-free rats.Lactic acid detected in the stomach of rats stimulated the motility of both small and large bowel while acetic acid, propionic acid and butyric acid found in the cecum stimulated the motility of the large bowel but not of small bowel. 相似文献
78.
Y Kanbayashi T Nakamura K Hosoda K Nogimori M Yajima M Ui 《Journal of biochemistry》1978,84(2):453-460
Based on the finding reported in the preceding paper (Kanbayashi, et al.: J. Biochem) that subunits of islets-activating protein (IAP), a new protein purified from the culture media of Bordetella pertussis, were inactive as such, but regained the original biological activities when recombined, the conditions required for recovery of the biological activities were studied. Essentially the same biological activities as the native IAP were recovered when the smallest subunit, F-3, was incubated with one of the other subunits, F-1 and F-2, at a pH of around 7, at temperatures below 30 degrees C and for longer than 12 h. During the incubation, association products were formed which were isolated by gel filtration as homogenous proteins that consisted of two subunits probably in a molar ratio of 1 : 1. The native IAP (consisting of two IAP subunits including F-3) were equipotent in enhancing insulin secretory responses, in inhibiting epinephrine-induced hyperglycemia, in inducing leukocytosis and in increasing histamine sensitivity in experimental animals. 相似文献
79.
The chemical synthesis of two new glycerophosphatide analogues containing steroid groups, i.e., 1,2-dipalmitoyl-rac-glyceryl-3-phosphoryl-3′β-cholesterol and 1,2-dipalmitoyl-rac-glyceryl-3-phosphoryl-20′-(3β-hydroxy norpregn-5-ene) is described. 相似文献
80.
George G. Rose M.D. Toshihiko Yajima 《In vitro cellular & developmental biology. Plant》1977,13(11):749-768
Summary Fetal mouse lungs were cultivated, using the dual-rotary circumfusion system for tissue culture, and their histotypic development
was surveyed for 75 days by phase-contrast and electron microscopy. Alveoli, terminal bronchioles and alveolar macrophages
were photographed periodically with still and time-lapse phase-contrast microscopy. Their histotypic appearance was confirmed
by electron micrographs of the 1- and 2 1/2-month-old specimens. These revealed typical alveoli surrounded by a basal lamina
and composed of types I and II pneumocytes containing various lamellar-body forms within the type II cells, the alveolar lumen,
and the alveolar macrophages. There was a shift from almost all type II cells in the 1-month-old alveoli to the presence of
frequent type I cells as constituents of the alveoli in the 2 1/2-month-old cultures. The terminal bronchioles were tubules
consisting of ciliated cells with Clara cells interspersed between them. The ciliated cells contained as many as 30 cilia
or basal bodies per section and numerous microvilli. They were attached to each other and to the Clara cells by junctional
complexes and accessory desmosomes which were generally in the apical ends of the cells. The Clara cells typically had glycogen
granules interspersed between lamellae of the endoplasmic reticulum, contained numerous well dispersed mitochondria, occasional
lysosome-like granules and crystalloid bodies which appeared to be tubular. Some Clara cells presented a moderately dense
secretory granule in the center of the whorl of the endoplasmic reticulum.
This work supported by Grant HL19684 from the National Heart and Lung Institute, National Institutes of Health.
Pregnant Strong A mice were kindly supplied by Dr. Henry Browning of the Department of Anatomy. 相似文献