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951.
Summary The role of water on the continous synthesis of geranyl esters by immobilized lipase fromHumicola lanuginosa No. 3 was studied in a packed-bed column reactor (PBR) installed with a molecular sieve column for water extraction. The conversion degress by PBR were highly influenced by the water concentration throughout the reaction which acted as a determinant on the reaction equilibrium. Almost 100% conversion of geranyl laurate could be achieved under the optimum water-controlled conditions. The stability of the PBR system was for 35 days with the half-life of 38 days. 相似文献
952.
Summary Methane was produced from H2 and CO2 byMethanobacterium
thermoautotrophicum cells fixed on the surface of hollow fibers. The mineral solution permeated through the inside of fibers was consumed by the cells, while the gaseous substrate flowing outside the fibers was directly metabolized to methane. Methane production was proportional to hollow fiber length i.e., contact area between cell layer and gas phase. In repeated batch cultures, the production rates of methane and cell mass were 33.1 L/L reactor/day and 1.75 g cells/L reactor/day, respectively with 90% conversion rate. 相似文献
953.
Protein kinase C phosphorylation of protamine is Ca2+ independent, but the addition of DNA renders it Ca2+ dependent 总被引:1,自引:0,他引:1
Protamine is a unique substrate of protein kinase C for its Ca2+-independent phosphorylation. The interaction between protein kinase C and protamine and the effect of DNA on the interaction was studied. Protein kinase C was retained in a protamine-immobilized Sepharose 4B column, even in the absence of Ca2+ and was eluted with ammonium sulfate or L-arginine. The eluted enzyme was fully activated by phosphatidylserine alone, when protamine was used as substrate. When DNA was included in the assay system, the activity elicited by phosphatidylserine alone was inhibited. The DNA effect on the activity in the presence of both Ca2+ and phosphatidylserine was much lower than on the activity elicited by phosphatidylserine alone, thereby demonstrating the Ca2+ sensitivity of protamine phosphorylation. 相似文献
954.
The 1H-nmr studies were extensively carried out to elucidate preferred conformations of dipeptides CH3C*O—X—NHCH3, with X = Abu, nVal, and Val in various solvents. The vicinal 1H—1H coupling constants for the NH—CαH moiety and those around the Cα—Cβ bond in the articulated side chain provided the information regarding the average conformation of these molecules. The results indicate that transformation of skeletal conformations takes place in solution among conformers having similar dihedral angles, θ, in the Karplus expression. 相似文献
955.
By means of one-dimensional polyacrylamide slab gel electrophoresis nonhistone nuclear proteins were compared in murine embryonal carcinoma cell clones with two X chromosomes; both are active in some clones and one of them is inactive in others and in a population of cells having only one X chromosome. Under our experimental conditions, we succeeded in finding two extra bands at approximately 46,000 Da in cells having an inactive X chromosome. Furthermore, a band at approximately 71,000 Da was significantly heavier in cells having an inactive X chromosome than in those having two active X or those having only one X chromosome. 相似文献
956.
E Odagiri R Demura H Demura T Suda N Ishiwatari Y Abe K Jibiki K Shizume 《Endocrinologia japonica》1988,35(6):795-802
We studied the suppressibility of cortisol secretion in 15 patients with Cushing's disease by measuring morning plasma cortisol level as well as the 24-hour urinary free corisol (UFC) excretion following single doses of increasing amounts of dexamethasone (ranging from 0.5 to 32 mg) given at 11 p.m. The mean plasma cortisol level in patients with Cushing's disease was twice as high as in normal subjects, whereas the mean UFC in these patients was 6 times as high. Plasma cortisol in seven patients were suppressed by less than 4 mg of dexamethasone (in 2 cases, less than 0.5 mg; in 3 cases, less than 2 mg; and in 2 cases less than 4 mg). In these cases, basal plasma cortisol and UFC were less than 25 micrograms/dl and 350 micrograms/day, respectively. Among the other eight patients, plasma cortisol was partially suppressed in 5 cases and not suppressed in 3 cases by high doses of dexamethasone (16-32 mg). In these cases the basal plasma cortisol and UFC were more than 25 micrograms/dl and 350 micrograms/day, respectively. There was a significant correlation between the basal plasma cortisol and UFC (r = 0.687, p less than 0.01). These data suggest that the suppression by increasing amounts of dexamethasone in most cases with Cushing's disease was related to the severity of hypercortisolism. 相似文献
957.
A balanced reciprocal translocation, 46,XY, t(2;12), was detected in a male infant who had the characteristic features of Sotos syndrome. His father's karyotype was normal, but his mother and an older brother had the same chromosomal abnormality without a history or clinical features of Sotos syndrome. 相似文献
958.
M Kodama H Kanaide S Abe K Hirano H Kai M Nakamura 《Biochemical and biophysical research communications》1989,160(3):1302-1308
Front surface fluorometry and porcine coronary arterial strips loaded with fura-2 were used to investigate the effect of endothelin on cytosolic Ca concentrations, [Ca]i, and on contractile force, the objective being to elucidate the mechanism of action. Both in the presence and absence of extracellular Ca, endothelin induced rapid and dose-dependent increases in [Ca]i and in contraction. When caffeine-sensitive and histamine-sensitive intracellular Ca stores were depleted, in Ca-free medium, a transient contraction but no increase in [Ca]i followed the subsequent application of endothelin. This Ca-independent component was largely inhibited by the relative protein kinase C inhibitor, H-7, but not inhibited by W-7, calmodulin antagonist. This component is probably linked to activation of protein kinase C. 相似文献
959.
Molecular cloning of an ice nucleation gene from Erwinia ananas and its expression in Escherichia coli 总被引:1,自引:0,他引:1
Soichi Arai Keiko Abe Satoshi Watabe Yasufumi Emori Michiko Watanabe 《FEMS microbiology letters》1989,61(1-2):53-56
Abstract An approximately 7 kbp genomic DNA fragment was cloned from an ice nucleation-active (ina) strain of Erwinia ananas and defined as to its restriction enzyme site. When the DNA fragment was introduced into E. coli MM294, a potent ice nucleation activity was expressed. Both 0.7 kbp truncation from the 5'-end and 1.7 kbp truncation from the 3'-end were also effective in expressing the ice nucleation activity in E. coli . Therefore, the resulting DNA fragment of approximately 5 kbp was considered to be an ina gene and named ina A. It existed as a unique gene in this strain of E. ananas . No corresponding ina gene existed in an ice nucleation-inactive strain of E. milletiae . 相似文献
960.
J. Abe H. Okamura Dr. Y. Ibata A. Motoyama I. Wakabayashi N. Ling W. K. Paull 《Histochemistry and cell biology》1990,94(2):127-133
Summary GnRH-associated peptide (GAP)-like immunoreactive elements located in the human hypothalamus were investigated by PAP immunocytochemistry
using specific antiserum against [pro-GnRH (14–69) OH]. Immunoreactive neuronal perikarya were distributed in the MPOA, PVN
and infundibular nucleus, with the largest numbers of GAP-like immunoreactive perikarya found in the infundibular nucleus.
We also detected the coexistence of GAP-like and GnRH-like immunoreactivities in the same neuronal perikarya in the MPOA by
using a double immunolabelling procedure. In addition to the above regions immunoreactive neuronal perikarya were present
in the region dorsal to the medial mammillary nucleus. GAP-like immunoreactive fibers were distributed in same areas that
immunoreactive perikarya were observed. Many immunoreactive terminals were found adjacent to capillaries in the infundibulum.
Immunoreactive dots, presumably terminals, were observed in the posterior pituitary and these were particularly evident along
the margin adjacent to the anterior pituitary. The distribution pattern and density of GAP-like immunoreactive neuronal elements
are compared with those of other mammalian species. We also compared GAP-like immunoreactive elements with that of GnRH as
has been previously observed in the human hypothalamus. 相似文献