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61.
Haruo Nagayama Koji Nagano Akira Ikezaki Tetsuo Tashiro 《Chronobiology international》1991,8(3):203-209
To investigate the possibility of chronotherapy with antidepressants for patients with depression, we gave single daily doses of clomipramine 150 mg/day to 30 patients with depression at three different times of day, i.e., morning, noon, or before bedtime, using a double-blind method over a 4-week period. Beneficial effects differed according to the administration time of day, with the most effective result being found for the administration at noon. Time-dependent differences in side effects were observed in tremors and dryness of mouth. An additional 10 patients were administered their medications three times a day by traditional, equally divided doses, and the efficacy was inferior than daily single doses at noon. The study results showed the significance of the administration time of day for the benefits and side effects of antidepressant therapy for depression. 相似文献
62.
Kazunori Maruyama Kouji Nagata Minoru Tanaka Hiromichi Nagasawa Akira Isogai Hironori Ishizaki Akinori Suzuki 《The protein journal》1992,11(1):1-12
We report the synthesis of bombyxin-IV, a disulfide-linked, heterodimeric, insulin superfamily peptide from the silkworm,Bombyx mori. The two chains (A- and B-chains) were synthesized separately by the solid-phase method using fluoren-9-ylmethoxycarbonyl (Fmoc) group as a protecting group for α-amino group. Three disulfide bonds were bridged step by step (A6–A11, A20–B22, and A7–B10) in a good yield. Synthetic bombyxin-IV was identical with natural one with regard to the retention time on a reversed-phase column and the molecular weight measured by mass spectrometry. Circular dichroism (CD) spectrum of the synthetic bombyxin-IV was very similar to that of the natural one. The specific activity of synthetic bombyxin-IV is equal to that of natural one (0.1 ng/Samia unit). These results suggest that the synthetic bombyxin-IV has the tertiary structure identical with the natural peptide. Our method developed for synthesis of bombyxin-IV would be generally applicable to the synthesis of insulin-like heterodimeric peptides. 相似文献
63.
Developmental Changes in the Bombyxin-and Insulin-like Immunoreactive Neurosecretory System in the Wax Moth, Galleria mellonella 总被引:1,自引:1,他引:0
Dun itn Frantiek Sehnal Akira Mizoguchi Hironori Ishizaki Hiromichi Nagasawa Akinori Suzuki 《Development, growth & differentiation》1990,32(6):637-645
Four medial neurosecretory cells (MNC) and 4 lateral neurosecretory cells (LNC) in each brain hemisphere, and one pair of cells in each thoracic ganglion (TG) of Galleria larva react with antibodies against bombyxin and insulin. Material secreted from the MNC and LNC is released mainly in the corpora allata, and that from the TG through the ventral median nerves. Intrinsic secretory cells of the corpora cardiaca (CC) also contain bombyxin-like, but not insulin-like material. The immunoreactivities all disappear during molts and reappear with resumption of feeding. In the MNC and TG they reappear for less than a day, but in cells of the CC immunoreactivity reappears for the whole feeding period. Before pupation, the LNC become temporarily immunopositive towards the end of feeding period, and the MNC and TG during the wandering period, i.e. at the time of prothoracic gland stimulation. Immunoreactivity disappears during the pupal molt. In pupae it is present in the 4 pairs of MNC and 1–2 pairs of LNC 12–48 hr after ecdysis, and in cells of the CC from 12 hr after ecdysis until the end of the pupal instar. In adult, immunoreactivity is restricted to 2 pairs of the LNC and to CC cells. 相似文献
64.
Three-dimensional structure of the crystalloid in the microbody of Kloeckera sp.: composite crystal model. 总被引:2,自引:1,他引:1
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Electron microscopic investigations using the cryosectioning technique, together with electron diffraction, optical diffraction, and computer simulation, were carried out for the determination of the intrinsic structure of the crystalloid in the microbody of Kloeckera sp. The lattice images seen in the cryosections could be changed from one to another by tilting the specimen at an appropriate angle, the images obtained being well consistent with those obtained by computer simulation. The electron diffraction patterns also agreed with those obtained by optical diffraction. The results demonstrated that the crystalloid was composed of two different types of particles, large and small ones, arranged alternately and making up the composite crystal of rock salt structure. Large particles seemed to consist of alcohol oxidase molecules, while the small particles were presumably made up of catalase molecules. 相似文献
65.
A gamma-like DNA polymerase devoid of DNA polymerase-alpha and -beta activities was prepared from the nuclear fraction of blastulae of the sea urchin, Hemicentrotus pulcherrimus. The enzyme sedimented at the position of an approximate sedimentation coefficient of 3.3 S under high salt conditions by sucrose gradient centrifugation. An isoelectric point was determined to be pH 5.8. The enzyme activity was sensitive to sulfhydryl blocking reagents. Poly(rA) . oligo(dT)12--18 followed by poly(dA) . oligo(dT)12--18 was effectively utilized as a template-primer. From the above results, this polymerase seems to resemble the vertebrate DNA polymerase-gamma. 相似文献
66.
Kaname Kawajiri Hiromichi Yonekawa Eiichi Hara Yusaku Tagashira 《Biochemical and biophysical research communications》1978,85(3):959-965
Studies were made on why guinea pigs are resistant to carcinogenesis by 2-acetylaminofluorene. Cytochrome P-448 and arylhydrocarbon hydroxylase were not induced in either the microsomes and nuclei of guinea pigs by 3-methylcholanthrene treatment. 3-Methylcholanthrene treatment caused only 2-fold increase in the binding of 2-acetylaminofluorene to DNA in nuclei isolated from guinea pigs, while it caused 17-fold increase in the binding in rat nuclei. Microsomes from 3-methylcholanthrene treated rats had 5 times more effect than Microsomes from 3-methylcholanthrene treated guinea pigs on the binding of 2-acetylaminofluorene to DNA of nuclei from untreated guinea pigs. N-Hydroxy-2-acetylaminofluorene combined equally well with the DNA of rats and guinea pigs. In guinea pigs, there was a good correlation between the low inducibility of cytochrome P-448 and the low binding of 2-acetylaminofluorene to DNA. Our results clearly showed that guinea pigs are resistant to tumor induction by 2-acetylaminofluorene through inability to carry out the first step of activation of 2-acetylaminofluorene. 相似文献
67.
The activity of Ca2+-dependent ATP pyrophosphohydrolase was found to fluctuate during spherule formation of the acellular slime mold Physarum polycephalum under starving incubation. The enzyme activity increased up to 16-fold at the 3rd day of the starvation, then decreased drastically to less than its original level. Column chromatography of the enzyme preparation suggested that the increase in the activity was due to de novo synthesis of a new isozyme. Cycloheximide inhibited the synthesis. The two isozymes were different in their Ca2+ sensitivity, the new one being less sensitive. 相似文献
68.
Hiromichi Sakaguchi Marvin Silver Arpad E. Torma 《Biotechnology and bioengineering》1976,18(8):1091-1101
The microbiological leaching of a chalcopyrite concentrate has been investigated using a pure strain of Thiobacillus ferrooxidans. The optimum leaching conditions regarding pH, temperature, and pulp density were found to be 2.3, 35°C, and 22%, respectively. The energy of activation was calculated to be 16.7 kcal/mol. During these experiments the maximum rate of copper dissolution was about 215 mg/liters/hr and the final copper concentration was as high as 55 g/liter. This latter value is in the range of copper concentrations which may be used for direct electrorecovery of copper. Jarosite formation was observed during the leaching of the chalcopyrite concentrate. When the leach residue was reground to expose new substrate surface, subsequent leaching resulted in copper extractions up to about 80%. On the basis of this experimental work, a flow sheet has been proposed for commercial scale biohydrometallurgical treatment of high-grade chalcopyrite materials. 相似文献
69.
Serum lipoproteins of the bullfrog, Rana catesbeiana, were studied during metamorphosis. Adult bullfrog has essentially one lipoprotein, designated β-lipoprotein. This β-lipoprotein migrates during electrophoresis to β-globulin region and it has a low hydrated density such that it exhibits floatation in a solvent of density 1.063. On the other hand, tadpole serum has one more lipoprotein, designated as α-lipoprotein, in addition to the β-lipoprotein. The α-lipoprotein migrates to the α-globulin region in zone electrophoresis and corresponds to the so called high density lipoprotein judging from ultracentrifugal behavior. Serum α-lipoprotein disappears and β-lipoprotein content decreases during metamorphosis. 相似文献
70.
M Fukushima Y Suzuki Y Toira I Matsunaga K Ochi H Nagano 《Biochemical and biophysical research communications》1975,66(2):632-638
The metabolism of 1α-hydroxyvitamin D3 (1α-OH-D3) was studied in rat liver perfused with [3H]-1α-OH-D3. [3H]-1α-OH-D3 was converted very rapidly to a more polar metabolite, which was identified as 1α,25-dihydroxy-vitamin D3 [1α,25-(OH)2-D3] by co-chromatography with synthetic 1α,25-(OH)2-D3 as well as by gas chromatography-mass spectrometry. [3H]-1α,25-(OH)2-D3 appeared in the perfusate as early as 20 min after addition of [3H]-1α-OH-D3, and its level in the perfusate increased linearly for at least 120 min. These data strongly indicate that 1α-OH-D3 is metabolized to 1α,25-(OH)2-D3, which exerts biological effects on bone and intestine. 相似文献