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排序方式: 共有517条查询结果,搜索用时 15 毫秒
1.
Seigo Sato Toshio Yajima Sukekuni Mukataka Joji Takahashi 《Biotechnology Techniques》1995,9(6):383-388
Summary Repeated batch hydrolysis of casein using immobilized protease were carried out at various do tensions and pH. At any of the pH tested, microbial contamination could be satisfactorily suppressed by maintaining high do. In continuous reaction, contamination could be suppressed throughout 40 days under the do of 190 ppm, whereas contamination was observed after 24 hours with the do of 2.5 ppm. 相似文献
2.
3.
T Yajima 《Histochemistry》1988,90(4):245-253
The ultrastructural localization of acid phosphatase (ACPase) activity was examined in cultured human gingival fibroblasts in the formative and resorptive phases. In the collagen-secreting fibroblasts, weak ACPase activity was demonstrated in the lysosomes, inner Golgi cisternae, and condensing vacuoles, and none was found in the Golgi-associated endoplasmic reticulum-lysosome system (GERL), presecretory granules, or secretory granules. On the contrary, collagen phagocytosis induced strong ACPase activity in the GERL, which was in addition to the weaker activity found in the same sites as those in the collagen-secreting cells. At the same time, collagen secretion was suppressed, and dense elongated secretory bodies associated with ACPase activity accumulated within the cells. When collagen fibrils had been interiorized in whole or in part within the phagosomes, primary lysosomes derived from the Golgi-GERL complex then fused with them to form phagolysosomes. Collagen degradation occurred within these bodies. The observations indicate significant differences in ACPase activity used as a marker for lysosomal enzyme activities in the different functional phases of fibroblasts. These results suggest that fibroblasts work only one way at a given time, viz., collagen synthesis or collagen degradation. 相似文献
4.
Inhibitory effect of norepinephrine on immunoreactive corticotropin-releasing factor release from the rat hypothalamus in vitro 总被引:2,自引:0,他引:2
T Suda F Yajima N Tomori T Sumitomo Y Nakagami T Ushiyama H Demura K Shizume 《Life sciences》1987,40(17):1645-1649
Effects of catecholamines on immunoreactive corticotropin-releasing factor (I-CRF) release from the rat hypothalamus were examined using a rat hypothalamic perifusion system and a rat CRF RIA in vitro. Norepinephrine had a potent inhibitory effect on I-CRF release in a dose-dependent manner at 0.1 nM-1 microM concentrations, but dopamine did not. This inhibitory effect of norepinephrine was completely blocked by propranolol, but only partially blocked by phentolamine. Isoproterenol also had a potent inhibitory effect at 0.01-100 nM concentrations, and a high dose of phenylephrine (10 nM) inhibited I-CRF release. Clonidine did not influence I-CRF release. These results suggest that norepinephrine inhibits I-CRF release mainly through the beta-adrenergic receptor and partially through the alpha 1-receptor. 相似文献
5.
Hisataka Shikama Motoyuki Yajima Michio Ui 《Biochimica et Biophysica Acta (BBA)/General Subjects》1980,631(2):278-288
Hepatic glycogen metabolism was studied in rats during the period of transition from the fed to fasted states. Glycogenic activity was measured in vivo based on the incorporation of [14C]glucose into liver glycogen. Its changes were almost parallel to the changes in glucogen synthase activity. Progressive accumulation of liver glycogen that occurred in the fed state was associated with a proportional increase in glycogenic activity. Within 4 h after the cessation of food intake, glycogenic activity showd a precipitous fall from the peak to its nadir without significant changes in glycogen content. Meanwhile, the glucose concentration in the portal vein decreased. Upon further development of fasting, glycogenic activity displayed a progressive regain, reciprocally as glycogen contents gradually decreased. The precipitous fall of glycogenic activity during the transition from the fed to fasted states was associated with a transient increase in plasma glucagon, and was partly overcome by the injection of anti-glucagon serum. It is concluded that the fall of portal venous concentration of glucose and secretion of glucagon act as a signal to initiate liver glycogen metabolism characteristics of the fasted or postabsorptive state. 相似文献
6.
Genetic affinities of inbred mouse strains of uncertain origin 总被引:5,自引:1,他引:4
Phylogenetic analyses of genetic data arising from 144 gene loci are used
to describe the interrelationships among 24 widely used inbred strains of
mice. An unordered-parsimony analysis gives a cladogram that is virtually
identical to the known genealogy of the mouse strains. A loss-parsimony
analysis is used to evaluate the hypothesis that the observed patterns of
genetic divergence among these 24 strains can be explained by the
segregation of residual heterozygosity arising from a small population of
highly heterozygous mice. The loss-parsimony cladogram is very similar to
both the unordered-parsimony cladogram and the known genealogy of the mice.
The phylogenetic analyses of these 144 loci are integrated with data on the
type and origin of the Y chromosome. Inclusion of the Y-chromosome data
provides additional insights into the genetic composition of several of the
original stocks used to produce the current inbred strains of mice. Ten
strains of uncertain origin are contained in these analyses, including AKR,
BUB, CE, I, NZB, P, RF, SJL, ST, and SWR. SJL is hypothesized to have been
derived from the same Swiss albino stock previously used to produce SWR.
The BUB strain appears to have had a complex origin and shows closest
genetic similarity to SWR and ST. AKR and RF are shown to be closely
related, while the I strain shows greatest genetic similarity to DBA/2 for
the 144 loci. However, I and DBA possess different types of Y chromosome.
The NZB strain shows genetic similarity to several stocks of both U.S. and
European origins. The power of the genetic data used in these analyses
reiterates that inbred strains of mice can be a valuable paradigm for
studies in evolutionary biology.
相似文献
7.
Kaeko Tozawa Eiji Arakawa Toshiyuki Chikuma Yoshihiro Oh-hashi Ryuichi Yajima Katsumichi Takeda Hiroshi Shinozaki† Takeshi Kato† 《Journal of neurochemistry》1990,55(3):745-749
Axonal transport of peptidylglycine alpha-amidating monooxygenase (PAM) activity was studied in rat sciatic nerves from 12 to 120 h after double ligations. The anterograde axonal transport increased and reached a plateau between 48 and 72 h and then decreased. The flow rate was 100 mm/day, and the molecular mass of the active entity was 70 kDa, which was determined by gel filtration. In contrast, there was no evidence for significant retrograde axonal transport. Anterograde axonal transport of immunoreactive cholecystokinin, a carboxy-terminal-amidated putative neuropeptide, was also found. These results suggest that PAM is transported by a rapid axonal flow and may play a role as a processing enzyme during transport or in the terminals of rat sciatic nerves. 相似文献
8.
γ-Isomer of 1,2,3,4,5,6-hexachlorocyclohexane (BHC) showed greater decomposition on γ or UV irradiation of five isomers of BHC in crystalline state or in 2-propanol solution. The α- and δ-isomer of BHC and known la, 2a, 3e, 4e, 5e-pentachlorocyclohexane were separated from the irradiation product of crystalline γ-BHC. Four compounds were isolated from the irradiation product of γ-BHC in 2-propanol. Two compounds were tetrachloro-cyclohexenes (C6H6C14): γ-isomer (mp 86 ~87°C) and ?-isomer (mp 99 ~ 100°C). The other two were isomers of pentachlorocyclohexane (C6H7C15). One of them (mp 78 ~ 8.5°C) was consistent with known meso-1e,2a,3a,4a,5e isomer. The molecular structure of the other (mp 75°C) established by X-ray crystal structure analysis was 1α, 2α, 3α, 4β, 5α configuration or le 2a 3e 4e 5e conformation of CI atoms. A reaction mechanism was proposed that included a radical chain reaction and chlorine atom migration. 相似文献
9.
The attempts of applying chiroptical spectroscopy to supramolecular chirality are reviewed with a focus on vibrational circular dichroism (VCD). Examples were taken from gels, solids, and monolayers formed by low‐molecular mass weight chiral gelators. Particular attention was paid to a group of gelators with perfluoroalkyl chains. The effects of the helical conformation of the perfluoroalkyl chains on the formation of chiral architectures are reported. It is described how the conformation of a chiral gelator was determined by comparing the experimental and theoretical VCD spectra together with a model proposed for the molecular aggregation in fibrils. The results demonstrate the potential utility of the chiroptical method in analyzing organized chiral aggregates. Chirality 27:659–666, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
10.
Ectomycorrhizal (ECM) syntheses between four ECM fungi, Laccaria amethystina, Hebeloma mesophaeum, Thelephora terrestris, and Tomentella sp., and Populus maximowiczii seedlings that are known to form ECM at a denuded area of Mt. Usu were performed in volcanic debris in a controlled growth
chamber. The percentage of ECM colonization and seedling growth were determined 3 months after inoculation. Seedlings were
successfully colonized by the inoculated ECM fungi with low contamination ratios. Seedling height and biomass were larger
in the inoculated seedlings than in the control, although the effects of inoculation on seedling growth varied with the ECM
fungus. 相似文献