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91.
We have identified a new mutation of Norrie disease (ND) gene in two Japanese males from unrelated families; they showed typical ocular features of ND but no mental retardation or hearing impairment. A mutation was found in both patients at the initation codon of exon 2 of the ND gene (ATG to GTG), with otherwise normal nucleotide sequences. Their mothers had the normal and mutant types of the gene, which was expected for heterozygotes of the disease. The mutation of the initiation codon would cause the failure of ND gene expression or a defect in translation thereby truncating the amino terminus of ND protein. In view of the rarity and marked heterogeneity of mutations in the ND gene, the present apparently unrelated Japanese families who have lived in the same area for over two centuries presumably share the origin of the mutation.  相似文献   
92.
The ratio of hapten and bovine serum albumin in an antigen conjugate was determined by matrix-assisted laser desorption/ionization mass spectrometry. A hybridoma secreting monoclonal antibodies against solamargine was produced by fusing splenocytes immunized with a solamargine-bovine serum albumin conjugate with HAT-sensitive mouse myeloma cell line, P3-X63-Ag8-653. Extensive cross-reaction of anti-solamargine antibodies against solasonine appeared. Aglycone of solamargine, solasodine cross-reacted with anti-solamargine antibodies resulting in a 43.8% cross-reaction. Insignificant cross-reaction appeared with tomatine (2.06%). The full measuring range of the assay extends from 57.5 pmol ml–1 to 11.5 nmol ml–1 of solamargine.  相似文献   
93.
We found that adenylate cyclase activity of human erythrocytes is potentially labile during isolation of their plasmalemma. Addition of 1 mM EGTA to solution used to remove hemoglobin from lysed cells protected activity. Human erythrocyte adenylate cyclase is minimally activated by catecholamines, in the absence or presence of exogenous guanyl nucleotide, but substantially by 5′-guanylyl imidodiphosphate or sodium fluoride and concentration-dependently by Mg2+ or Mn2+. Basal catalytic activity is an age-dependent component of the human erythrocyte; 5′-guanylyl imidodiphosphate- or fluoride-activated activities decline with cellular maturation proportionally to the decrease in basal activity.  相似文献   
94.
The primary leaves from corn seedlings grown for 6 days were harvested, frozen with liquid N2 and extracted in a Tris buffer (pH 8.5, 250 millimolar) containing 1 millimolar dithiothreitol, 10 millimolar cysteine, 1 millimolar EDTA, 20 micromolar flavin adenine dinucleotide and 10% (v/v) glycerol. Nitrate reductase (NR) in the crude extract was stable for several days at 0°C and for several months at −80°C. The enzyme was purified using (NH4)2SO4 fractionation, brushite-hydroxyl-apatite chromatography and blue-sepharose affinity chromatography. The enzyme was eluted from the blue-sepharose column with a linear gradient of NADH (0-100 micromolar) or with 0.3 molar KNO3. About 10% of the original activity was recovered with NADH (NADH-NR). It had a specific activity of about 60 to 70 units (micromoles NO2 per minute per milligram protein). A sequential elution with NADH followed by KNO3 (0.3 molar) or KCl (0.3 molar) yielded 2 peaks. Rechromatography of each peak gave two peaks again. These results indicate that we are dealing with two forms of the same enzyme rather than two different NR proteins. The two NRs had different molecular weights as judged by chromatography on Toyopearl. The NADH-NR was more sensitive than the NO3-NR to antibody prepared against barley leaf NR. In Ouchterlony assays a single precipitin line, with completely fused boundaries, was observed.  相似文献   
95.
By using a monospecific anti-polygalacturonase-2 antibody, a54K-dalton polypeptide was detected in in vitro translationproducts by a wheat germ cell-free translation system programmedwith polyadenylated RNA from ripe tomato pericarp tissue. Thisputative precursor of polygalacturonase was about 9K daltonslarger in molecular weight than polygalacturonase-2. (Received December 12, 1983; Accepted May 17, 1984)  相似文献   
96.
Insoluble collagen of granulation tissue produced by carrageenin injection was solubilized by pepsin treatment and purified. The pepsin-solubilized insoluble collagen contained partially degraded collagen fragments and the amounts of these small fragments of collagen were much greater in the resorbing granulation tissues than in the growing tissues, suggesting that these small fragment were formed in the course of resorption of granulation tissue, including collagen breakdown.  相似文献   
97.
The formaldehyde method was used to examine the interaction of PGE1 with morphine, β-endorphin and Met-enkephalin on rat mast cells by their effects on IgE-mediated 14C-serotonin release. PGE1 (2×10?8?2×10?5 M) caused a dose-related inhibition of the mediator release 1 min after an antigen challenge, and morphine (3×10?7?3×10?5 M) reversed this PGE1 effect dose-dependently and stereospecifically; naloxone (2×10?4 M) antagonized this action of morphine. β-Endorphin (3×10?7?10?5 M) and Met-enkephalin (3×10?6?10?4 M) mimicked this morphine action dose-dependently and were antagonized by naloxone (2×10?4 M). These results suggest that morphine and endorphins modulate immunological mediator release from rat mast cells through opioid receptors.  相似文献   
98.
The proliferation and differentiation of human leukemic B cells (B-CLL cells) with anti-Ig and T cell-derived helper factors are described. Stimulation of B-CLL cells with anti-Ig and T helper factors could induce proliferation as well as differentiation into IgM- and IgG-producing cells. Neither anti-Ig nor T helper factors alone could induce any proliferation and/or differentiation of B-CLL cells. Not only whole molecules of anti-Ig but also F(ab')2 fragments could induce proliferation and differentiation of B-CLL cells in the presence of T helper factors, but monovalent Fab' fragments were not effective. Induction of both IgM and IgG with the same idiotype was confirmed by immunofluorescent and SDS-PAGE analysis. By employing an IL 2-dependent cytotoxic T cell line and a TRF-responsive B cell line, T cell factors were separated into a fraction with IL2 activity but no TRF activity and a fraction with TRF activity but no IL 2 activity by chromatofocusing. Anti-Ig and IL 2 fraction could induce proliferation of B-CLL cells, but TRF fraction was not effective for the induction of proliferation in anti-IG-stimulated cells. For IgM and IgG production, anti-Ig and both IL 2 and TRF fractions were required. Depletion of IL 2 fraction in the first 2 days' culture inhibited Ig production, whereas the absence of TRF fraction in the first 2 days did not show any inhibitory effect on Ig production.  相似文献   
99.
Pathological observation on experimental swine dysentery   总被引:1,自引:0,他引:1  
Experimental swine dysentery caused by 4 cultured strains (S73/2, DJ183, DJ70 and DK762) of Treponema hyodysenteriae was studied pathologically. The distribution and quantity of treponemes were examined on tissue sections stained by the Warthin-Starry method. Of the organs the colon contained the largest number of treponemes and the cecum and rectum the second largest number. Histopathological lesions were restricted to the large intestine. They ranged from mild catarrhal colitis in the mild case to desquamative, hemorrhagic colitis in the severest case. The severity of lesion was closely associated with the quantity of treponemes present. There was no difference in quality of the lesion between any two of the strains used in this study. Electron microscope revealed a large number of free treponemes present in the intestinal lumen and crypts. Treponemes were seen more frequently in the cytoplasm of goblet cells than in that of intestinal epithelial cells. They were also observed in desquamated degenerative epithelia. A small number of them were found in intact epithelia. Morphologically, the treponeme had a granular protoplasmic cylinder at the center which was surrounded by a thin envelope. Between the cylinder and the envelope there were axial fibrils.  相似文献   
100.
The liberation of 2,4-dinitrophenolate ion from 2,4-dinitrophenyl sulfate (DNPS) in aqueous organic solvent with 0.1 N sodium hydroxide was accelerated upon addition of an equimolar amount of Oxime-I (10-hydroxy-11-hydroxyimino[20]-paracyclophane) to the sulfate ester. Oxime-I was found to undergo covalent participation at the oxime group to afford oxime O-sulfonate. The rate acceleration with Oxime-I was larger than that with β-CD (cycloheptaamylose). The catalytic efficiency of Oxime-I has been ascribed primarily to the tighter inclusion of the substrate ester into the more hydrophobic Oxime-I cavity provided by the effective apolar paracyclophane skeleton, as well as to the greater nucleophilicity of the oxime group than of the hydroxyl group in β-CD. Consequently, Oxime-I may be considered as a conventional model for arylsulfatases and sulfotransferases, providing the effective binding process for the substrate.  相似文献   
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