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991.
Spotted fever group rickettsia in dogs in Japan 总被引:1,自引:0,他引:1
C Morita Y Tsuboi A Iida S Mohri S Handa M Fukui 《Japanese journal of medical science & biology》1989,42(4):143-147
Prevalence of antibody against spotted fever group-rickettsia in dogs (14/134) from the northern part of Shikoku Island, where spotted fever group rickettsia infection in human is endemic, is significantly higher than that in dogs (4/189) from nonendemic areas. 相似文献
992.
N Matsuura J Konishi S Harada K Yuri K Fujieda K Kasagi Y Iida S Fujimoto M Fukushi N Takasugi 《Endocrinologia japonica》1989,36(6):865-871
To elucidate the relationship between the mother's TSH-receptor antibody activities and the status of thyroid dysfunction in their offspring, blood was taken from 5 mothers with chronic thyroiditis with potent thyrotropin (TSH)-receptor blocking activity, and the potency of TBII and TSBAb activity was assayed more quantitatively. In those mothers whose infants suffered from neonatal hypothyroidism, the 50% inhibition of binding of labeled TSH to its receptors was obtained at more than 30 to 50-fold dilution, while in those mothers whose infants had transiently increased TSH or were euthyroid, the titers were of less than 30-fold dilution. Similarly, in those mother whose infants suffered from neonatal hypothyroidism, the 50% inhibition of TSH-induced cAMP accumulation was obtained at approximately 400 to 3000-fold dilution, while in those mothers whose infants had transiently increased TSH or were euthyroid, the titers were of less than 50-fold dilution. On the other hand TBII activity was much less potent in serum from patients with Graves' disease. These results suggested that the titration of serum with dilution to obtain 50% inhibition of labelled TSH binding to its receptor may be the simplest way to predict thyroid dysfunction of the newborn infants born to mothers with chronic thyroiditis. 相似文献
993.
Kaoru Miyamoto Yoshihisa Hasegawa Takashi Minegishi Mitsuo Nomura Yoshitaka Takahashi Masao Igarashi Kenji Kangawa Hisayuki Matsuo 《Biochemical and biophysical research communications》1982,107(3):820-827
A peptide having gonadotropin-releasing activity was isolated in a yield of 2.5 μg from an extract of 2,000 chicken hypothalami. The biopotency was monitored using rat anterior pituitary cell culture system. The peptide differs from mammalian Luteinizing Hormone-Releasing Hormone (LH-RH) in its behavior during chromatographic separation (ionexchange and high performance liquid chromatography) and in its reaction towards anti-LH-RH antiserum directed against the C-terminal region of the LH-RH molecule. The peptide (chicken LH-RH) stimulates secretion of both LH and FSH from rat anterior pituitary cells. The biological potency of this peptide was about 4 % of that of the authentic decapeptide estimated in the rat anterior pituitary system. The amino acid composition is (Ser, Pro, Glx2, Gly2, Leu, Tyr, His, Trp), which differs from mammalian LH-RH only in that one Arg residue is replaced by a Glx residue. Based on the behavior on CM cellulose chromatography and the reaction towards anti-LH-RH antiserum, one possible structural candidate for this peptide (chicken LH-RH) is [Gln8]-LH-RH. 相似文献
994.
Yôichi Iida 《Journal of molecular biology》1982,159(1):167-177
Calmodulin is one of the calcium-binding proteins and is distributed widely in eukaryotes. The amino acid sequences were studied of calmodulin taken from bovine brain, scallop (Patinopecten), sea anemone (Metridium senile) and tetrahymena (Tetrahymena pyriformis). One notable feature of the primary structure of calmodulin is its internal homology. It can be subdivided into four domains with similar amino acid sequences. This homology implies that the primary structure of calmodulin has been elongated twice by intragenic duplication. Using this intragenic duplication model, the amino acid sequences of calmodulin from those four species were analyzed in detail. This kind of approach has proved very useful for investigation of the origin and evolution of this protein. 相似文献
995.
Sixty-seven compounds were characterized in the wax of Sargassum fulvellum. Characteristic components were the 5-methylhexyl esters of octanoic, decanoic, lauric, myristic, palmitic, palmitoleic, stearic, oleic, linoleic and linolenic, and the 2-ethylhexyl esters of the same acids. The wax of S. fulvellum contains hydrocarbons (1.6%), esters (21.8%), free acids (74.9%) and free alcohols (0.3%). The principal free alcohols range in chain length only from C6 to C7. 相似文献
996.
Takamiya Ken-ichiro; Kimura Keiko; Doi Michio; Nishimura Mitsuo 《Plant & cell physiology》1980,21(3):405-411
The O2 uptake linked to NADH2 and succinate oxidation was observedin chromatophores from photosynthetically grown Chromatium vinosum. The maximal rate was 60120 nmoles of O2 uptake per minper {diaeresis}mole of bacterio-chlorophyll. The rate of O2uptake linked to NADH2 oxidation was higher in the neutral-to-acidicpH range than in the alkaline range, whereas that linked tosuccinate oxidation was higher in the alkaline range. The O2 uptake linked to NADH2 oxidation was inhibited by rotenone,amytal, antimycin A, KCN and NaN3, while that linked to succinateoxidation was inhibited by antimycin A, KCN and NaN3. Malate,citrate, pyruvate, acetate, -ketoglutarate, NADPH2 and thiosulfatedid not serve as substrates for the O2 uptake of isolated chromatophores. The rates of the O2 uptake linked to both NADH2 and succinateoxidation were not stimulated by adding uncouplers or underphosphorylating conditions. Little or no ATP was synthesizedin the dark, coupled to either NADH2 or succinate oxidation,in spite of a high activity of photophosphorylation in Chromatiumchromatophores. (Received February 26, 1980; ) 相似文献
997.
Toshihiko Osawa Harue Ishibashi Mitsuo Namiki Tsuneo Kada 《Biochemical and biophysical research communications》1980,95(2):835-841
Mutagenicity of 1,4-dinitro-2-methyl pyrrole, a new mutagen isolated from the reaction mixture of sorbic acid and sodium nitrite, was found to be destroyed by treatment with ascorbic acid or cysteine. Chemical studies revealed that the loss of mutagenicity was due to reduction from the C-nitro to C-amino group. 相似文献
998.
Tamura Noriaki; Itoh Shigeru; Yamamoto Yasusi; Nishimura Mitsuo 《Plant & cell physiology》1981,22(4):603-612
The nature of the electron transfer reaction between reducedplastocyanin and P700 oxidized by flash illumination was studiedin P700-enriched Triton subchloroplast fraction 1 particles.An addition of monovalent salts to the suspension at neutralpH increased the reaction rate at low concentrations (>20mM). Salts of divalent cations showed a similar effect at muchlower concentrations (>2 mM), This effect was not dependenton the concentration and the valence of anions. The increaseof rate at low salt concentrations was observed at pH's above5, but below pH 5 the rate was decreased by adding salts. Atabout pH 5, the rate was not affected by salts. Apart from thesesalt effects, the optimum pH for the reaction rate was observedbetween 5.5 and 6.5. The reduction rate depended sigmoidally on the added plastocyaninconcentration at pH 6.8 and 4. A Michaelis-Menten type relationshipwas observed at about pH 5. The half-saturation concentrationof plastocyanin became lower as the salt concentration increasedat pH 6.8, while it became higher by adding salt at pH 4. The effects of salts on the rate of electron donation from othermetalloproteins and artificial electron donors to P700 werealso studied. It is concluded, from the analysis with the Gouy-Chapmantheory, that the net charges on the electron donors and themembrane surfaces mainly determine the response of the P700reduction rate to salt addition. The salt addition changes mainlythe local concentration or accessibility of electron donorsto P700. (Received January 12, 1981; Accepted March 6, 1981) 相似文献
999.
Itoh Shigeru; Kuramitsu Shinichi; Oku Tatsuo; Nishimura Mitsuo 《Plant & cell physiology》1981,22(5):881-889
Photoactivation of the oxygen-evolving system in intact leavesand in isolated chloroplasts of dark-grown spruce (Picea abies)seedlings was studied by measuring the transient time coursesof the delayed and prompt fluorescence of chlorophyll. The delayedfluorescence (measured between 0.5 and 12.5 msec after 15 msecillumination) as well as the prompt fluorescence of intact leavesincreased in intensity when the oxygen-evolving system was activatedby a short period of illumination. After illumination of chloroplastsisolated from the dark-grown seedlings, the long-lived componentof delayed fluorescence (> 100 msec) was enhanced, but notthat in the millisecond time range. An analysis of the ionicdependencies of the intensities of prompt and delayed fluorescenceshowed that the thylakoid membranes of chloroplasts isolatedfrom dark-grown seedlings had almost the same electrostaticproperties as those of mature angiosperm chloroplast membranes.
3Present address: Faculty of Education, Hiroshima University,Hiroshima 730, Japan. (Received February 25, 1981; Accepted June 5, 1981) 相似文献
1000.
Akira Watanabe Mitsuo Takeuchi Masafumi Nagata Kazuichi Nakamura Hiroyuki Nakao Hirofumi Yamashita Susumu Makino Minoru Harada Tsutomu Hirasawa 《Experimental Animals》2003,52(5):419-423
The DS-Nh (DS Non-hair) mouse is a spontaneous hairless mutant of the DS mouse. The inheritance mode of the Nh mutation is autosomal dominant, and the Nh locus is mapped to Chromosome 11. The roles of the Nh mutation in spontaneous dermatitis and IgE hyperproduction were studied using an Nh congenic strain with a genetic background from the BALB/c mouse. In contrast to DS-Nh (Nh/+) mice, BALB/c-Nh (Nh/+) mice under conventional conditions showed a marked increase in serum IgE, without the development of dermatitis. These results suggest that IgE hyperproduction is regulated by the Nh mutation, while other genetic factor(s) are also involved in the development of dermatitis. 相似文献