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61.
Assignment of the S-antigen gene (SAG) to human chromosome 2q24-q37   总被引:2,自引:0,他引:2  
We report the mapping of the gene coding for the S-antigen (48-kDa protein) to human chromosome 2 using somatic cell hybrids. In situ hybridization further confirms this assignment and regionally maps the gene to 2q24-q37.  相似文献   
62.
63.
Mg++ -activated and -inhibited ATPases from mung bean hypocotyls   总被引:1,自引:0,他引:1  
Mg++-activated and inhibited ATPases were isolated from dark-grownmung bean hypocotyls. The enzymes hydrolyzed nucleoside tri-,di- and monophosphates and ß-glycerophosphate. Theeffect of Mg++ was most marked when ATP and other nucleosidetriphosphates were used as substrates. Mg++-activated ATPases: The activity of enzyme-I was localizedin the membranes and was not released by treatment with 0.1%deoxycholate. Enzyme-II was released and separated by CM-cellulosecolumn chromatography. Enzyme-V was separated from the solublefraction of the cell homogenate by DEAE-cellulose column chromatography.The rates of activivation by Mg++ of enzyme-II and enzyme-Vwere very small compared to that of enzyme-I. Mg++-inhibited ATPases: Enzyme-II and -IV were precipitatedwith 50–80% ammonium sulfate from the soluble fractionof the cell homogenate and were separated by successive columnchromatographies on Sepharose 6B and DEAE-cellulose. The activitiesof enzyme-III and -IV were inhibited by Mg++, when ATP, UTPand GTP were used as substrates. Enzyme-III was purified approximately38-fold, and was more remarkably inhibited by Mg++ than wasenzyme-IV. 1Present address: Institute for Plant Virus Research, 959 Aobacho,Chiba 280, Japan. (Received January 7, 1974; )  相似文献   
64.
Concentrated and purified Sabin and virulent strains of poliovirus types 1, 2 and 3 were inactivated with formalin at 37 C. By addition of 5.4 microM arildone, an antiviral agent, to the virus suspension, the stability of D antigen increased in both Sabin and virulent strains of all types, especially in virulent type 1 Mahoney strain. The drug had neither any inhibitory nor enhancing effect on the formalin inactivation. When antibody response was compared in guinea pigs, Sabin strains inactivated in the absence of arildone were less immunogenic against homotypic virulent strains than inactivated vaccine prepared from virulent strains. On the other hand, Sabin strains inactivated in the presence of arildone were equally immunogenic. These results indicate that it is possible to prepare from Sabin strains a potent and safe inactivated vaccine having an immunogenicity comparable to that prepared from virulent strains.  相似文献   
65.
Seventy per cent of the phospholipid in mitochondria from sweet potato roots was removed by aqueous acetone treatment. The amount of phospholipid that could be rebound to these lipid-depleted mitochondria roughly corresponded to the amount of phospholipid in untreated mitochondria. The activities of NADH-cytochrome c oxidoreductase, succinate-cytochrome c oxidoreductase, cytochrome oxidase, and succinoxidase in lipid-depleted mitochondria were restored by addition of mitochondrial phospholipid to about 60, 50, 15, and 35%, respectively, in comparison to untreated mitochondria. The capacity of lipid-depleted mitochondria from 14-day cold-stored tissue to bind mitochondrial phospholipid from healthy tissue was lower than that from healthy tissue. However, there was no large difference in activities of NADH-cytochrome c oxidoreductase and succinate-cytochrome c oxidoreductase between both phospholipid rebound lipid-depleted mitochondria from healthy and 14-day cold-stored tissues. On the other hand, activity of succinoxidase in phospholipid rebound lipid-depleted mitochondria from 14-day cold-stored tissue was decreased by about 50% of that from healthy tissue. Furthermore, the capacity of lipid-depleted mitochondria from 2-day cold-stored tissue to bind mitochondrial phospholipid from healthy tissue was higher than that from healthy tissue.  相似文献   
66.
Indoleacetic acid (IAA) stimulates the incorporation of 14C-proline into both the cyloplasmic and the cell wall fractions of the hypocotyl of mung bean (Phaseolus aureus Roxb. cv. Black). It neither stimulates the transfer of 14C-proline from the cyloplasmic fraction into the cell wall fraction, nor the retention of 14C-proline in the wall or cytoplasmic fractions. Moreover, the stimulation of growth caused by IAA parallels the stimulation of the incorporation of proline into the cytoplasmic fraction, but does not parallel the stimulation into the cell wall fractions. The stimulation of the incorporation into the cyloplasmic fraction seems to appear within 30 minutes after auxin treatment, at about the same time the increase in the growth is observed in response to IAA, suggesting a connection between these effects. On the other hand, the stimulation of the proline incorporation into the cell wall fraction seems to require more than 90 minutes after auxin treatment, suggesting no close connection between growth and proline incorporation into the cell wall fraction.  相似文献   
67.
The intracellular transport of mucus glycoprotein precursor (apomucin) from endoplasmic reticulum (ER) to Golgi was quantitated by the immunoprecipitation with 3G12 antimucin monoclonal antibody and by estimation of the apomucin glycosylation using UDP-[3H]galactose. The assembly of the entities carrying apomucin to Golgi was assessed by electron microscopy and by quantitation of the incorporation of [14C]choline, [14C]ethanolamine, and [14C]oleic acid into their lipids. The microscopic image of the isolated transport components revealed a population of 80- to 100-nm vesicles with occasional membranes of the ER used for their synthesis. On the average, the vesicles contained 82 ng apomucin/microgram of protein and 80-90% of the total incorporated lipid precursors. From that, 91% of [14C]choline was detected in phosphatidylcholine, and 9% in phosphatidylethanolamine, lysophosphatidylcholine, and sphingomyelin. With [14C]oleate, 54% of the label was incorporated into ceramide, diglyceride, and phosphatidic acid, 35% to phosphatidylcholine, 7% in phosphatidylethanolamine, and 2% in sphingomyelin. After incubation of the vesicles with Golgi, the apomucin was found glycosylated and the lipids of the transport vesicles incorporated into Golgi membranes. The fusion of the vesicular membranes was accompanied by the synthesis of sphingomyelin. In the Golgi, 39-55% of the radiolabeled phosphatidylcholine of transport vesicles was converted to sphingomyelin. The results indicate that the newly synthesized membranes of apomucin transporting vesicles are enriched in phosphoglycerides and ceramides. Upon fusion with the Golgi, the membranes of the vesicles are replenished with sphingomyelin by exchange reaction between phosphatidylcholine and ceramide.  相似文献   
68.
Characterization of rat T cell subset antigen by monoclonal antibody   总被引:4,自引:0,他引:4  
6B2-B8 T cell hybridoma cells were used to immunize mice, and immune spleen cells were fused with NS/1 myeloma cells. One clone, designated RTH-7, reacted with 89.5% of rat thymocytes, 30.2% of rat spleen cells, and 42.3% of rat lymph node cells. The RTH-7 reacted with a subset of rat T cells but not with B cells. Double staining analysis demonstrated that RTH-7 stained a rat T cell subset distinct from R1-10B5-positive cells that were known to be equivalent to mouse Lyt-2. It was revealed that RTH-7 and W3/25 recognize different antigenic epitopes on the same molecule. The RTH-7 as well as W3/25 substantially inhibited the production of interleukin 2 by cells in mixed lymphocyte reaction and the lymphocyte proliferation induced by mixed lymphocyte reaction. The RTH-7 inhibited the lymphocyte proliferation induced by Con A whereas W3/25 failed to do so. The RTH-7 defined antigen has a molecular weight of 53,000 under reducing condition and 47,000 under nonreducing condition. The RTH-7 defined antigen showed a wide range of heterogeneity in pI (6.2-8.8). The associated molecule of approximate molecular weight of 27,000 was occasionally detected with the RTH-7 defined antigen in 6B2-B8 T cell hybridoma cells as well as peripheral T cells but not in thymocytes. Thus, RTH-7 detects a cell surface antigen of a functional T cell subset of rat origin.  相似文献   
69.
Effects of the combination of low temperature and silicone treatment on the storage of grape callus (Vitis vinifera L. x V. labrusca L. cv. Kyoho; V. vinifera L. cv. Koshusanjaku) were examined. In Kyoho, the calli were stored at 10°C successfully for up to 360 days. Embryogenic calli of Koshusanjaku stored at 10°C retained the ability of embryogenesis after 360 days of storage. However, the color of both calli became brownish. This was improved by the combination of low temperature and silicone treatment. The calli of Kyoho survived by the storage under the combination of 15°C and silicone. Embryogenic calli stored at 10 and 15°C in combination with silicone survived for 360 days, and regenerated only after transfer onto a regeneration medium. Thus the combination of low temperature and silicone affects the longevity of the grape callus.  相似文献   
70.
The preparation and antigenic properties of estrone-3-glucuronide- and estriol-3-glucuronide-bovine serum albumin conjugates in which the hapten is linked to the carrier protein through an (O-carboxymethyl)oxime bridge at the C-6 position on the steroid nucleus, have been described. Antibodies raised against the two immunogens in the rabbit possessed high specificity to estrone-3-glucuronide and estriol-3-glucuronide, respectively, exhibiting little cross-reactivities with other estrogen conjugates and no cross-reactions with related steroids except for free estrogens, their 3-methyl ethers and 3-sulfates. The cross-reactive antibodies were eliminated by partial immunoadsorption on affinity chromatographic media using the estrone-3-methyl ether 17-(O-carboxymethyl)oxime- and estriol-3-methyl ether 16 (or 17)-hemisuccinate-aminohexyl Sepharose conjugates, respectively. The purified antisera exhibited no cross-reactivities with free estrogens and ring A conjugates of estrone and estriol.  相似文献   
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