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71.
72.
and
1986. Complete resistance to challenges with Hymenolepis nana cysticercoids derived from mouse, rat and beetle in mice. International Journal for Parasitology 16: 623–628. When BALB/c and dd strains of mice were given eggs of Hymenolepis nana, they all became completely resistant not only to challenge with mouse-derived cysticercoids but also to challenges with rat-derived and beetle-derived cysticercoids. Serum IgG antibodies at 47–60 days post egg inoculation reacted strongly with these three different host-derived cysticercoids when examined by IFA test, but IgA and IgM isotypes reacted very weakly. Antibodies of infected mouse sera (IgG, IgM and IgA were examined) reacted not only with the protoscolex (scolex of the excysted juvenile) but also with the outer cyst wall. By contrast, uninfected mouse sera and immune sera prepared seven days post cysticercoid inoculation did not react at all. Antigens of both cyst wall and protoscolex appeared to be of parasite origin and not of host origin, and appeared similar in parasites from the different host species. 相似文献
73.
Ieharu Hishinuma Tetsuro Ishii Hiroyuki Watanabe Shiro Bannai 《In vitro cellular & developmental biology. Plant》1986,22(3):127-134
Summary Mouse lymphoma L1210 cells maintained in vitro at a high cell density for a certain time period adapted themselves to the
in vitro environment and were able to grow indefinitely. From these adapted cells, more than 30 clones were isolated. They
all had much higher activity to take up cystine than the original L1210 cells, supporting a previous view that the deficiency
of the cystine uptake limits the survival and growth of L1210 cells in vitro. The cystine uptake of one cloned cell line was
characterized. The enhanced uptake of cystine in these cells was mainly mediated by a Na+-independent, saturable system and was potently inhibited by glutamate and some other anionic amino acids, but less by aspartate.
Such activity of cystine uptake was not observed in the original L1210 cells. The results suggest that, upon adaptation in
vitro, L1210 cells acquire a new cystine transport activity necessary for survival and growth in vitro. 相似文献
74.
The effect of a 0.25% clofibrate diet for 2 weeks on peroxisomal and mitochondrial beta-oxidation in chicken liver was studied. The activities of antimycin antimycin A-insensitive palmitoyl-CoA oxidation (peroxisomal beta-oxidation) and carnitine acetyltransferase increased about two-fold. The activities of palmitoyl-CoA-dependent O2 consumption (mitochondrial beta-oxidation) and carnitine palmitoyltransferase were also slightly activated by the administration of clofibrate, but not significant. Thus, clofibrate may be a typical drug which activates the peroxisomal beta-oxidation more than the mitochondrial one in various species. The effect of clofibrate on peroxisomal carnitine acetyltransferase was the same as that on the mitochondrial one in chicken liver. Serum lipids were not lowered, but hepatomegaly was observed in the present experiment with chicken. 相似文献
75.
M Kiyoki N Kurihara S Ishizuka S Ishii Y Hakeda M Kumegawa A W Norman 《Biochemical and biophysical research communications》1985,127(2):693-698
[23 (S), 25 (R)]-1 alpha,25-Dihydroxyvitamin D3-26,23-lactone [( 23 (S),25 (R)]-1 alpha,25-(OH) 2D3-26,23-lactone) increased dose-dependently alkaline phosphatase activity in osteoblastic cells, clone MC3T3-E1, in medium containing 0.1% bovine serum albumin. The maximal stimulated enzyme activity per mg protein was 1.6-fold over that of control cultures at 250 pg/ml. The metabolite also increased collagen synthesis in a dose-related fashion. On the other hand, [23 (S),25 (R)]-1 alpha,25-(OH)2D3-26,23-lactone decreased slightly but significantly 45Ca mobilization, and blocked the resorptive action of 1 alpha,25-dihydroxyvitamin D3 but not that of parathyroid hormone, in mouse calvaria in organ culture. These results indicate that [23 (S),25 (R)]-1 alpha, 25-(OH)2D3-26,23-lactone stimulates the differentiation of osteoblasts and inhibits bone resorption in vitro. 相似文献
76.
Isolation and characterization of the bacteriophage T4 tail-associated lysozyme. 总被引:8,自引:0,他引:8
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Direct evidence has been obtained that the tail-associated lysozyme of bacteriophage T4 (tail-lysozyme) is gp5, which is a protein component of the hub of the baseplate. Tails were treated with 3 M guanidine hydrochloride containing 1% Triton X-100, and the tail-lysozyme was separated from other tail components by preparative isoelectric focusing electrophoresis as a peak with a pI of 8.4. The molecular weight as determined from sodium dodecyl sulfate electrophoresis was 42,000. The tail-lysozyme was unambiguously identified as gp5 when the position of the lysozyme was compared with that of gp5 of tube-baseplates from 5ts1/23amH11/eL1ainfected Escherichia coli cells by two-dimensional gel electrophoresis. The tail-lysozyme has N-acetylmuramidase activity and the same substrate specificity as gene e lysozyme; the optimum pH is around 5.8, about 1 pH unit lower than for the e lysozyme. We assume that the tail-lysozyme plays an essential role in locally digesting the peptidoglycan layer to let the tube penetrate into the periplasmic space. The tail-lysozyme is presumably also responsible for "lysis from without." 相似文献
77.
The xyloglucan present in the 24% KOH extract of the cell wallsof suspension-cultured rice cells was characterized by fragmentationanalysis with Trichoderma viride cellulase and Aspergillus oryzaeß-D-glucosidase. The xyloglucan is composed mainlyof the following oligosaccharide units: Results showed that the xyloglucan of suspension-cultured ricecells is more extensively branched than is that of rice seedlings.Another structural characteristic of the former xyloglucan isthe presence of D-galactosyl-D-xylosyl side chains that arenot found in the latter. (Received June 15, 1984; Accepted January 11, 1985) 相似文献
78.
N Hamada T Ishii M Hasegawa N Ishikawa T Tabata Y Okuno K Ito S Matsuura H Morii M Wada 《Hormones et métabolisme》1985,17(6):301-305
In a 19-year-old Japanese male (case 1) with thyrotoxic periodic paralysis (TPP), an increase of plasma glucose concentration together with abnormally high levels of serum immunoreactive insulin (IRI) was observed preceding a spontaneous attack of paralysis. Therefore, the plasma glucose, glucagon, epinephrine, norepinephrine, serum IRI, growth hormone and cortisol levels, and the erythrocyte insulin receptors were measured in case 1 and a 40-year-old Japanese male (case 2) with TPP during attacks of paralysis induced by prolonged glucose loading. In case 1, the serum IRI concentration was elevated to the extraordinarily high level of 655.0 microU/ml at the beginning of paralysis, and at that time, the plasma glucose concentration was 147 mg/dl. However, when paralysis was not induced by a similar glucose loading during methimazole treatment, the serum IRI and plasma glucose levels at the corresponding time after glucose loading were 20.9 microU/ml and 87 mg/dl, respectively. Furthermore, the affinity of the erythrocyte insulin receptors was decreased during the attack. In case 2, plasma glucose and serum IRI concentrations were increased in accordance with the initiation of paralysis although the blood levels of hormones counteracting insulin were not significantly changed. These findings suggest that there is something interacting with the normal action of the insulin in the early phase of paralysis. 相似文献
79.
Genome type analysis of adenovirus type 4 isolates, recently obtained from clinically different syndromes in some areas in Japan 总被引:1,自引:0,他引:1
C S Ren N Nakazono S Ishida S Fujii T Yoshii S Yamazaki K Ishii K Fujinaga 《Japanese journal of medical science & biology》1985,38(4):195-199
DNA cleavage analyses with EcoRI, HindIII and BamHI were carried out to investigate genome types of recent Ad 4 isolates obtained from acute respiratory disease (8 strains), and ocular disease (11 strains) in Japan. DNA cleavage patterns of all 19 isolates studied were identical regardless of whether they were recovered from respiratory tract or conjunctiva, but were distinct from that of the prototype strain. 相似文献
80.
Pyroglutamyl-lysyl-leucyl-argininal (Pyr-Lys-Leu-Argal) immobilized on gel matrix through the epsilon-amino group of its lysine residue was shown to be an efficient biospecific affinity adsorbent for purification of urokinase. Pyr-Lys-Leu-Argal dibutylacetal, a precursor of this immobilized ligand, was synthesized by a fragment condensation procedure, in which one of the thermolysin-digestion products of leupeptin dibutylacetal, H-Leu-Argal dibutylacetal, was used as a key intermediate. The precursor was coupled to CH-Sepharose 4B with the aid of a water-soluble carbodiimide, and its acetal protecting group was then removed by mild acid treatment to free the essential aldehyde function. The Sepharose derivative thus prepared was shown to adsorb urokinase selectively and effectively from a crude human urine preparation at neutral pH and to release the bound enzyme under mild acidic conditions. The present technique afforded a highly purified urokinase preparation abundant in the high-molecular form with 90% recovery. The complex formed between urokinase and the immobilized ligand was found to have a dissociation constant of about 2 X 10(-4)M. 相似文献