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41.
The distribution density of opioid receptors in the brain of El mice (seizure-susceptible strain) was examined to determine the relation between seizures and the opioid system. Saturation curves and Scatchard plots of [3H]2-d-alamine-5-d-leucine enkephalin binding revealed that the opioid delta receptor density in adult El mice during interictal periods was significantly increased in the cerebral cortex, hippocampus, and septal area. It was further shown that the concentration of such receptors in 25-day-old El mice that had no seizures was also significantly increased in the hippocampus and septal area, with no changes in apparent affinities, as compared with in the corresponding regions in ddY mice (seizure-nonsusceptible strain; the mother strain of El). Such up-regulation of opioid receptors in the El mouse brain could result from deficits in endogenous opioid peptides, which could be associated with the pathogenesis of seizure diathesis in the El mouse.  相似文献   
42.
Biological activities of two groups of synthesized lipid A analogs, the counterpart of biosynthetic precursor, Lehmann's Ia type, 406, and E. coli lipid A type, 506, as well as their non-phosphorylated, and mono-phosphorylated analogs were investigated. The activities employed included four bone marrow cell reactions in mice, mice skin reaction, leukocytes migration in rabbits' cornea, and hemagglutination. Compound 406 and 506 elicited bone marrow reactions in mice and hemagglutination of mouse RBC, although 406 failed to elicit hemorrhage and necrosis also in mice skin. Compound 406 did not elicit corneal reaction in rabbits. The results suggest that for elicitation of this reaction and mice skin reaction, acyloxyacyl structure is required. Cytotoxicity and thromboplastin production of four bone marrow reactions had been reported by us to be endotoxic reactions, since these had not been elicited by peptidoglycan of Lactobacillus and Staphylococcus (1981) and 300 series synthesized analogs (1984) which did not have endotoxic structures. From these results, it seems that these two marrow reactions and hemagglutination require, as does the limulus test, the lipid A part structure as is present in 406.  相似文献   
43.
Summary Maximum production of alkaline serine protease by Bacillus alcalophilus subsp. halodurans KP 1239 was achieved after 24 h cultivation, at an initial pH of 7.6, on a medium containing 1.0% sodium citrate, 0.3% yeast extract, and 0.3% KH2PO4. The enzyme was purified to crystalline form from culture broth. The enzyme was most active at 60° C and at pH 11.5. The molecular weight, isoelectric point and sedimentation coefficient in water at 20° C were estimated as 29 000, 8.8 and 3.3S, respectively. The N-terminal amino acid sequence was Ala-Gln-Ser-Val-Pro-Trp-Gly-Ile-Ser-Arg-Val-Gln-Ala-Pro-Ala-Ala-His-Asn-Arg-Gly-. The enzyme shared its antigenic determinants with B. alcalophilus ATCC 21522 serine protease, but not with the subtilisins Carlsberg and BPN. Offprint requests to: Yuzuru Suzuki  相似文献   
44.
We report a missense mutation in an adult Japanese patient with acid alpha-glucosidase (GAA) deficiency. A TC to GT transition at nucleotides 1585–1586, was identified. This transition resulted in an amino acid substitution of Ser-529 to Val (S529V) in exon 11. We also have demonstrated that the S529V mutation abolishes the catalytic activity of the enzyme. Our data suggest that this mutation is the cause of the clinical manifestation known as adult-onset GAA deficiency. The missense mutation described here is a new mutation, and the first identified in Japanese patients with GAA deficiency. Received: 23 May 1995  相似文献   
45.
Water extracts of the compost produced from activated sludge and coffee residue were found to be selectively inhibitory to seed germination of some legumes. Germination rate of white clover (Trifolium repens L.), red clover (Trifolium pratense L.) and alfalfa (Medicago sativa L.) seeds were reduced to 2, 29 and 73% of the control, respectively, by water extracts of the compost (20 g l–1). However, the extracts did not show any inhibition to seed germination of sorghum (Sorghum bicolor Moench), African millet (Eleusine coracana Gaertn.), and Komatsuna (Brassica rapa L.) at the same concentration. The inhibitors in the compost extracts were separated by ion-exchange chromatography and reverse-phase high performance liquid chromatography (HPLC) and the inhibitory activities of seed germination were tested with white clover seeds. Five inhibitors were isolated and identified as 3,4-dichlorophenylacetic acid (3,4-DCP), 3,4-dichlorobenzoic acid (3,4-DCB), 3,4,5-trichlorophenylacetic acid, 3,4,5-trichlorobenzoic acid and mono-2-ethylhexylphthalate by 1H-, 13C-NMR spectroscopy and mass spectrometry. The inhibitory activities of some authentic chemicals of the inhibitors and the related compounds were compared. The results indicated that the main inhibitor in the compost could be 3,4-DCB, which was contained at the concentration of 6.58 mg kg–1 compost and showed the strongest inhibitory effect on seed germination of white clover among the tested compounds.  相似文献   
46.
A chemical method for the determination of dermatan sulfate (DS) and oversulfated dermatan sulfate has been developed and applied to the pharmacokinetic study of these polysaccharides in experimental animals. The analytical procedure includes a simple preparation step of administered DS and oversulfated DS from blood plasma, HPLC for the separation and detection of DS and oversulfated DS using an Asahipak NH2P-50 column, fluorometric reaction of the polysaccharides with guanidine in a strong alkaline medium. DS and oversulfated DS were extracted from plasma by treating it with proteinase to remove plasma proteins and recovered with endogenous plasma glycosaminoglycans by ethanol precipitation. Finally, DS and oversulfated DS were analyzed by fluorometric HPLC. The detection limits of DS and oversulfated DS were 10 and 20 ng, respectively. Furthermore, we demonstrated that artificial oversulfation of DS increased its biological half-life after intravenous administration to rats.  相似文献   
47.
The surface coat, ciliary process, and microvilli of the lamprey neuromast were examined with electron microscopy after tannic acid prefixation and lectin histochemistry. The neuromast was found to exist in the form of a dermal mound with a furrow in the middle. On the bottom of the furrow, the hair cell was characterized by a kinocilium and 15–20 stereocilia, arranged along the longitudinal axis of the furrow. Spanning structures were demonstrated between the kinocilium and stereocilia as well as between stereocilia. The surface coat, enhanced by tannic acid prefixation, was particularly rich over the surface of the supporting cell; by contrast, it was thin over the hair cell. Some lectins (PNA, GS-I, SBA, WGA) showed affinity to the surface coat of the supporting cell as well as the hair cell, and the others (RCA-I, MPA, ConA) showed affinity only to the supporting cell. These differences in the structure and affinities of the surface coat suggest an extracellular milieu highly specialized for the hair cell in this particular form of the mechanoreceptor.  相似文献   
48.
Kato Y  Tsunoda Y 《Theriogenology》1994,41(6):1315-1322
Different numbers of CD-1 mouse zygotes(1, 5, 10, 20, 40 and 60) were cultured in 10 mul M16 medium, in M16 medium+EDTA, in M16 dedium+SOD+thioredoxin, and in CZB medium, respectively. When the zygotes, regardless of the number, were cultured with M16, no blastocysts could be obtained. The suitable ratio of embryos to 1 mul of M16 medium+EDTA or M16 medium+SOD+thioredoxin was 1:1 or 2:1. Medium volume from 1 to 10 mul did not affect blastocyst development when the embryo density was 1:1. However, blastocysts obtained from zygotes cultured singly had fewer cell numbers and showed inferior development to live fetuses after transfer to recipients. When CZB medium was used, suitable embryo density was not clear. The ratio of embryos to volume of culture medium was shown to be an important factor for in vitro culture of mouse zygotes.  相似文献   
49.
Kato Y  Oguro T  Tsunoda Y 《Theriogenology》1994,41(7):1483-1488
Experiments were conducted to test the hypothesis that the nucleo/cytoplasmic ratio of mouse embryos determines the time of blastocele formation. Half the volume of 2-cell stage embryos was removed from each blastomere by micropipette to alter the nucleo/cytoplasmic ratio. Reduced embryos whose nucleo/cytoplasmic ratio increased and non-treated control embryos were cultured in vitro to compare the timing of division to the 4-cell stage and blastocele formation. Reduced 2-cell embryos formed blastoceles significantly earlier than the controls (49.0 +/-2.9 vs 52.2 +/-6 h) and with fewer cells, although division into the 4-cell stage was significantly delayed (11.4 +/-4.4 vs 9.0+/-2.4 h). The cell number of blastocysts 70 h after treatment and developmental ability of blastocysts after transfer to pseudopregnant recipients were the same for the reduced and control groups. The present study indicates that the nucleo/cytoplasmic ratio of embryos may possibly be an important factor that determines the time of blastocele formation.  相似文献   
50.
Aplopsora corni sp. nov. is proposed for a rust fungus whose uredinial and basidial stage occurs onCornus controversa (Cornaceae) in Hokkaido. This new species is separated by its larger urediniospores and probasidia from the morphologically closely relatedA. nyssae onNyssa aquatica andN. sylvatica (Cornaceae) distributed in southern North America.  相似文献   
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