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91.
Hiroki Yoshimi Shigeru Matsukura Satoru Sueoka Masaaki Fukase Makoto Yokota Yukio Hirata Hiroo Imura 《Life sciences》1978,22(24):2189-2195
A sensitive and specific radioimmunoassay for β-endorphin has been developed with an antiserum obtained in a rabbit immunized with β-endorphin contained in crude porcineACTH preparations. The minimal detectable quantity was 5 pg. The antiserum used reacted slightly with ovine β-lipotropin (5.5 %), but showed negligible cross-reactivity with other fragments of β-lipotropin, α-MSH and ACTH. Using this radioimmunoassay we have observed the presence of “big-big” β-endorphin (“big” β-lipotropin) with apparent molecular weights of 37,000 and 31,000 in human and rat pituitaries respectively, in addition to β-lipotropin and β-endorphin, by Sephadex gel-chromatography and sodium dodecyl sulfate polyacrylamide gel electrophoresis. 相似文献
92.
93.
Clostridium botulinum type A spore challenges were given orogastrically to adult mice that had been treated with metronidazole. The organism multiplied in the intestinal tract for up to five days if it was administered 9–48 h after the last dose of metronidazole. The known antibacterial spectrum of metronidazole indicated that obligate anaerobic bacteria are important in the natural resistance of adult mice to colonization byC. botulinum, but treatment with the antimicrobial agent did not reduce the number of these bacteria in the cecum and colon. 相似文献
94.
Effects of an inhibitor of glucosylceramide synthase on glycosphingolipid synthesis and neurite outgrowth in murine neuroblastoma cell lines. 总被引:2,自引:0,他引:2
1-Phenyl-2-decanolyamino-3-morpholino-1-propanol (PDMP), an effective inhibitor of UDP-glucose:ceramide glucosyltransferase, caused inhibition of cell growth in murine neuroblastoma cell lines. Metabolic labeling of glycosphingolipids with [14C]galactose in NS-20Y, Neuro2a, and N1E-115 cells showed reduced incorporation of radioactivity into gangliosides and neutral glycosphingolipids when threo-PDMP was present in the medium. Treatment of NS-20Y cells with threo-PDMP resulted in a time-dependent decrease in mass levels of gangliosides and neutral glycosphingolipids. After 24 h in the presence of 50 microM threo-PDMP, neutral glycosphingolipid mass was reduced to 32%, where glucosylceramide was the most affected (90% decrease). The ganglioside mass was reduced to 57% of the original content. Neurite outgrowth from neuroblastoma cells in serum-free medium was significantly inhibited by threo-PDMP in a dose-dependent manner. Threo-PDMP also caused retraction of neurites which had been induced to extend in serum-free medium. Pretreatment of cells with GM1 partially restored the ability of NS-20Y cells for neurite outgrowth in the medium containing threo-PDMP. These results suggest a possible role for glycosphingolipids in neurite outgrowth of murine neuroblastoma cells. 相似文献
95.
T R Saito S Aoki Y Shutoh R Hokao Y Sasaki H Amao Y Wakafuji M Sugiyama K W Takahashi 《Jikken dobutsu》1991,40(4):561-563
The ejaculatory response induced by p-chloroamphetamine (PCA) in male rats, hamsters and mice was observed during 2 hours after the injection. The animals were treated intraperitoneally with PCA at doses ranging from 0.78125 to 160 mg/kg. The ED50 (effective dose in 50% of animals) values of PCA for the initiation of ejaculation in rats and hamsters were 1.3397 (1.0732-1.6725) and 0.1105 (0.0802-0.1522) mg/kg, respectively. On the other hand, no ejaculation was observed in any mice at any doses examined. So we concluded that there are species differences in the ejaculatory response, induced by PCA, among rats, hamsters and mice. 相似文献
96.
Mated female mice of the IVCS strain, aged 90 (control group), 180, 210, 240, 270, 300, 330, 360 and 420 days old, were studied for pre- and post-implantation loss of embryos. The percentage of pre-implantation loss in mice aged 90 to 210 days was 1.7/11.8 (14.4%) to 2.7/11.7 (23.1%). In mice aged 240 to 300 days it increased significantly as compared to the controls (46.5-90.2% versus 14.4%). It reached 100% in 300-days-old mice. The post-implantation loss of embryos and/or fetuses in mice aged 90 to 240 days was 1.0/10.2 (9.8%) to 2.5/9.0 (27.8%). In mice aged 270 to 300 days it increased significantly compared to the controls (100% versus 9.8%). The decrease in reproductive activity appeared first in a decrease in litter size, followed by a decrease in the number of blastocyst and implantation sites, and finally by anovulation during the process of aging in IVCS mice. 相似文献
97.
T R Saito R Hokao S Aoki N Chiba M Terada M Saito A Dohbutsu H Amao Y Wakafuji M Sugiyama 《Jikken dobutsu》1991,40(3):337-341
It is well known that yohimbine has a history of popular use because of its supposed aphrodisiac properties. The present study was done to determine whether yohimbine can modify the copulatory behavior of aged male rats. Adult male rats of the Wistar-Imamichi strain, 52 weeks of age and weighing 600-650g, were injected intracerebroventricularly with yohimbine hydrochloride (5, 10 micrograms/10 microliters/rat) or vehicle. Each male was then given the opportunity to mate with a receptive female for 30 min after administration of yohimbine or vehicle. Yohimbine produced significant decreases in the latency to initial mounting and significant increases in the number of mountings. However, there was no ejaculation in the yohimbine-and vehicle-treated males. This study is the first to clearly establish an important modulator of sexual arousal for yohimbine in aged male rats. 相似文献
98.
99.
The synthesis patterns of female-specific proteins of Schistosoma japonicum were further investigated with particular reference to the 34 kDa putative eggshell precursor protein. Adult male and female worms of S. japonicum were metabolically labelled with 14C-tyrosine, 14C-glycine and 35S-methionine in vitro. The rates of amino acid incorporation for female worms were significantly higher than for males in all radiolabelling experiments. Labelled proteins were resolved by two-dimensional gel electrophoresis and visualized by fluorography. By using 14C-tyrosine and 14C-glycine, the 34 kDa female protein band resolved into three major spots with pI 6.0, 5.8 and 5.6. On the other hand, labelling studies using 35S-methionine failed to reveal synthesis of any corresponding spots at Mr 34 kDa. These results, together with the observations that eggshell hydrolysates are very rich in glycine but poor in methionine, suggested that the 34 kDa putative eggshell precursor protein of S. japonicum consists of at least three isoelectric forms. In addition, we have demonstrated several other female-specific polypeptides synthesized by this worm. 相似文献
100.
M Taniguchi H Sawaki H Sasakawa T Hase T Sugiyama 《European journal of biochemistry》1992,204(2):611-620
The cytosolic and mitochondrial isozymes of aspartate aminotransferase (AspAT) function in the C4 dicarboxylate cycle of photosynthesis. We constructed a cDNA library from leaf tissues of Panicum miliaceum, an NAD-malic-enzyme-type C4 plant and screened the library for AspAT isozymes. A full-length cDNA clone for cytosolic AspAT was isolated. This clone contains an open reading frame that encodes 409 amino acids. We also isolated two cDNA clones for different precursors of mitochondrial AspAT. Comparing these two sequences in the coding regions, we found 12 amino acid substitutions out of 28 base substitutions. The encoded amino acid sequences predict that mitochondrial AspAT are synthesized as precursor proteins of 428 amino acid residues, which each consist of a mature enzyme of 400 amino acid residues and a 28-amino-acid presequence. This prediction coincides with the observation that the in vitro translation product of the mRNA for mitochondrial AspAT was substantially larger than the mature form. A comparison of the amino acid sequences of the AspAT isozymes from P. miliaceum with the published sequences for the enzymes from various animals and microorganisms reveals that functionally and/or structurally important residues are almost entirely conserved in all AspAT species. 相似文献