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71.
By the use of cloned cDNAs for protein kinase C isozymes alpha, beta I, beta II, gamma, and those for novel protein kinase C, epsilon and zeta, the expression of the corresponding mRNA species was examined in various mouse tissues, human lymphoid cell lines, and mouse cell lines of neuronal origin. In adult brain, mRNAs for all the isozymes of PKC family are expressed. However, the expression of these mRNA species in brain is low at birth. A similar pattern of expression was also observed for beta I/beta II mRNAs in spleen. These expression patterns are in clear contrast to that for beta I/beta II mRNAs in thymus where the mRNAs are expressed at birth and the levels of expression decrease with age. Human lymphoid cell lines express large amounts of PKC beta mRNAs in addition to PKC alpha. Further, nPKC epsilon mRNA is expressed in some of these cell lines. On the other hand, all the mouse cell lines of neuronal origin tested express nPKC epsilon and zeta in addition to PKC alpha. In a mouse neuroblast cell line, Neuro 2a, down modulation of mRNAs for both PKC alpha and nPKC epsilon was observed in association with in vitro differentiation.  相似文献   
72.
H Saito  T Suzuki  K Ueno  T Kubo  S Natori 《Biochemistry》1989,28(4):1749-1755
Sarcocystatin A is a cysteine proteinase inhibitor purified from the hemolymph of Sarcophaga peregrina larvae [Suzuki, T., & Natori, S. (1985) J. Biol. Chem. 260, 5115-5120]. We isolated a cDNA clone for sarcocystatin A and analyzed the structure and expression of the sarcocystatin A gene. Sarcocystatin A consists of 102 amino acid residues. Significant homology was found between amino acid sequences of sarcocystatin A and other mammalian cystatins, and highly conserved sequences among mammalian cystatins were also found in sarcocystatin A. Using cloned cDNA as a probe, we investigated expression of the sarcocystatin A gene during the development of Sarcophaga. Results showed that this gene was transiently activated in the very early embryonic stage and in the pupal stage, suggesting that sarcocystatin A participates in morphogenesis of larval and adult structures of Sarcophaga.  相似文献   
73.
Summary Carbonic anhydrase III has been localized using the avidin-biotin-glucose oxidase complex (ABC) method in the submandibular gland of the rat and hamster. This isozyme, which is predominant in skeletal muscle, was observed in intercalated duct, striated duct and excretory duct cells in the rat submandibular glands. In contrast, only some striated duct cells in hamster submandibular glands were stained.  相似文献   
74.
During our studies on toxic substances from clinically isolated Nocarida, a new isolate identified as Nocardia otitidiscaviarum from cutaneous nocardiosis was found to produce a toxic substance called HS-6 that had strong in vitro as well as in vivo toxicity. The mouse intraperitoneal LD50 value was 1.25 mg/kg and the ED50 value for L1210 cultured cells was 0.3 ng/ml. The structure of HS-6 was determined and found to belong to the 16-membered macrocyclic group with a molecular formula of C43H68O12. HS-6 also showed activity against pathogenic fungi such as Cryptococcus neoformans.  相似文献   
75.
Inbred mutant El mice are highly susceptible to convulsive seizures upon tossing stimulation. The levels of excitatory (e.g. glutamate and aspartate) and inhibitory amino acids [e.g. -aminobutyrate (GABA)] were examined in discrete regions of stimulated El mice [El(+)] non-stimulated El mice [El(-)] and ddY mice, which do not have convulsive disposition. In comparison with ddY, a general increased levels of aspartate, glutamate, glutamine, and taurine were detected in brain regions of El(-). The levels of GABA and glycine were almost the same in ddY and El(-). Compared to El(+), the levels of aspartate, glutamate, glutamine, and GABA in El(-) were either the same or higher. In the case of taurine and glycine, the levels in El(-) were either the same or lower than El(+). Alanine is special in that El(-) have a higher level than El(+) in hippocampus but lower in cerebellum. Furthermore, while marked changes were registered in several brain regions, none of the amino acids investigated showed any significant differences in the hypothalamus of three different groups of mice.  相似文献   
76.
The maximum theanine production by Camellia sinensis cultured cells was achieved by culturing in the modified MS medium containing 2 mg/l indole-3-butyric acid, 0.1 mg/l kinetin, 0 mM NH4NO3 and 39.6 mM KNO3 with 40 mM ethylamine hydrochloride or 20 mM ethylamine hydrochloride and 10 mM L-glutamic acid. Other primary amines, such as methylamine, n-butylamine, 2-hydroxyethylamine, 2cyanoethylamine, aniline, benzylamine and phenylethylamine, were also biotransformed to N5-alkyl-L-glutamine derivatives by C. sinensis cultured cells.Abbreviations IBA indole-3-butyric acid - K kinetin - MS medium Murashige and Skoog's basal medium (1962) - NMR nuclear magnetic resonance Part 70 in the series Studies on Plant Tissue Culture. For Part 69 see Furuya et al. (1990).  相似文献   
77.
In two forest stands, one domonated byAbies spectabilis, and the other byPinus wallichiana-Picea smithiana, 198 cores were taken from 105 conifers in May 1983 and the annual ring widths were measured. The annual ring widths usually had significant similarities between cores taken from the same tree and with cores taken from different trees. these similarities increased with tree size. The climatic change affected the large trees more strongly than it did the small trees. Micro environmental changes, such as canopy gap affected the small trees more strongly. Annual ring widths were also correlated with the annual precipitations at Jumla 30 km south of the plots for a recent 20 year period. A multiple regression analysis between ring width and seasonal precipitation showed that the growth ofA. spectabilis was correlated primarily with the rain from May to August and secondarily with that from September to December in the previous year.  相似文献   
78.
Pre- and postoperative intradermal administration of OK-432 enhanced the SU-PS skin reaction in patients with gastric cancer, but failed to prevent a fall in the NK activity induced by the operation.The change in NK activity was not associated with a change in the proportion of Leu 7-positive cells, but was related to Leu 11a-positive cells. Intradermal injection of OK-432 increased the proportion of Leu 7-positive cells in the patients in whom they accounted for less than 20% of lymphocyte population. The case was the same with Leu 11a-positive cells.Intravenous injection of OK-432 tended to increase suppressor-inducer T cells (CD4+2HA+ cells), B cells and Leu 7-positive cells. Particularly, the proportions of OK-M1-positive cells and MHC class II antigen-positive cells increased in all patients. Immunotherapy with OK-432 given intravenously at a dose of 0.1 KE appeared to be safe because no side effects were essentially observed.  相似文献   
79.
Binding affinities of modified steroidal anthrasteroids, 3 beta-hydroxy-3a beta,6-dimethyl-2,3,3a,4,5,8,9,10,10a beta,11,11a beta, 11b alpha-dodecahydro-1H-cyclopenta[a]anthracene-8-one (1) and 3a beta,6-dimethyl-2,3,3a,4,5,8,9,10,10a beta,11,11a beta,11b alpha-dodecahydro-1H-cyclopenta[a]anthracene-3,8-dione (2), the steroid oxendolone and the nonsteroid AA560, for the androgen receptor (AR) of Shionogi carcinoma 115 (SC115) and their effects on the growth of SC115 were investigated in vivo and in vitro. The inhibitory effects of these compounds on testosterone 5 alpha-reductase of SC115 tissues were also measured. The relative binding affinities of these compounds were 3.17-0.03% of that of dihydrotestosterone, and their rank order was (1) greater than AA560 greater than oxendolone much greater than (2). In the presence of 10(-9) M testosterone, anthrasteroids and AA560 inhibited the growth of SC115 cells at 10(-7) M in a serum-free medium, but oxendolone did not. In the absence of testosterone, (1), (2) and oxendolone promoted cell growth at 10(-6), 10(-7) and 10(-7) M, respectively. However, AA560 nearly completely blocked cell growth at 10(-5) M. At a 2 mg daily dose for 13 days, (1) and AA560 powerfully inhibited tumor growth in castrated DS mice treated with testosterone propionate but oxendolone had almost no effect. Anthrasteroids and oxendolone showed weak but significant agonistic activity in vivo. Anthrasteroids markedly inhibited 5 alpha-reductase activity of SC115, oxendolone weakly and AA560 not at all. The remarkable antiandrogenic activities of (1) and AA560 may partially result from their higher affinities for the AR of SC115 but other yet unknown mechanisms may also contribute to these activities.  相似文献   
80.
Summary The authors succeeded in establishing a murine model of systemic candidiasis being disseminated from the primary gastrointestinal lesions caused by oral inoculation of Candida albicans. Using this model, an attempt was made for detecting the Candida antigen by enzyme-linked immunosorbent assay using avidin-biotin (AB-ELISA) from the serum of infected mice.Gastrointestinal candidiasis was formed in all of the 20 mice treated with the drugs (antibiotics, antineoplastic agents, hydrocortisone, etc.) and inoculated orally with C. albicans. Fourteen of these mice suffered from submucosal candidiasis, and C. albicans was cultured from the visceral organs in 12 of them. The assay by AB-ELISA was able to detect 1.0 ng/ml Candida mannan in the mouse serum. The Candida antigen was detected in the sera of 11 of the 14 mice with submucosal candidiasis. However, the antigen could not be detected in the sera of the 6 mice with intramucosal candidiasis.The assay by AB-ELISA is more sensitive and specific for the diagnosis of systemic candidiasis than other serological assays.  相似文献   
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