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181.
The ability of 17 inorganic compounds (POCl3, PSC13, PC13, P2O5, P2S5, P4S3, P4S7, PC15, Sb2O5, As2O5, BiOC12, SeOC12, SO2C12, Sb2S5, VOC12, SiC14 and CrO2Cl2) dissolved in pyridine or 2,2,4-trimethyl pentane, to enhance subsequent staining of tissue components with toluidine blue, phosphotungstic acid-hematoxylin (PTAH), leukofuchsin, and dihydroxydinaphthyl-disulfide (DDD) was studied. Eight of these compounds were also tested for ability to enhance staining with Alcian blue 8GN and Luxol fast blue MBS. Nine of the 17 compounds produced increased staining of certain tissue components with leukofuchsin, 13 with toluidine blue, 16 with PTAH, and 16 with DDD. The results suggest additional approaches to identification of tissue entities by induced metachromatic basophilia and leukofuchsin positivity as well as by the other stains studied, and also suggest a number of hitherto unstudied modes of reaction between the dyes used and reactive groups of tissue components. Many reactions of the compounds tested, with reactive groups known to be present in tissue components, are basecatalyzed, so that choice of solvent can influence the results obtained. 相似文献
182.
Prenatal diagnosis of cystic fibrosis by microvillar enzyme assay on a sequence of 258 pregnancies 总被引:3,自引:1,他引:2
Summary Prenatal diagnosis of cystic fibrosis by microvillar enzyme assay on amniotic fluid supernatant has been carried out on 258 sequential pregnancies with a 1 in 4 recurrence risk, all with known outcome. In general the three enzymes evaluated, -glutamyltranspeptidase, aminopeptidase M and the intestinal isoenzyme of alkaline phosphatase, showed a high degree of concordance. However, there were two unusual patterns of microvillar enzyme activity; in seven cases a low -glutamyltranspeptidase activity was associated with elevated values of intestinal alkaline phosphatase, and in ten cases there were isolated low values of intestinal alkaline phosphatase. The former pattern was found to be associated with cystic fibrosis in five cases, while the latter was associated with a normal outcome in all ten cases. A retrospective analysis of enzyme values suggested that the optimal system for minimizing false positives and false negatives was to define foetal cystic fibrosis as a sample where two of the three microvillar enzymes were below a cut-off of half the median value for the gestational week. If such scoring were applied to the cases where conventional microvillar enzyme patterns were observed, the false positive rate was 2.3% and the false negative rate 4.4% between 17 and 20 weeks of gestation. 相似文献
183.
Bonnie J. Brake Hazel W. Wilkinson Robert Gelok Arthur Markovits 《Current microbiology》1984,10(5):261-264
The purpose of this study was to determine whether cynomolgus monkey antisera toLegionella pneumophila serogroups 1–6 antigens could be used as positive controls in the indirect immunofluorescence assay (IFA) for legionellosis. Immunoelectrophoretic mobilities and Ouchterlony analyses with heavy chain-specific antisera and IFA titers with immunoglobulin class-specific conjugates were used to show antigenic relatedness of immunized monkey immunoglobulins to those produced as a result of infection in humans. Identical immunoelectrophoretic precipitation patterns were obtained for human and monkey sera with antihuman gamma, mu, and alpha heavy-chain-specific antisera. Ouchterlony analyses showed precipitin bands of partial identity between human and monkey IgG, IgM, and IgA classes. IFA titers in the monkey hyperimmune antisera were >16,000 with antihuman conjugate. These data suggest that hyperimmune cynomolgus monkey antisera are suitable alternatives to human sera for IFA-positive controls. 相似文献
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188.
Tehryung Kim M. K. U. Chowdhury Hazel Y. Wetzstein 《In vitro cellular & developmental biology. Plant》1999,35(1):51-56
Summary β-glucuronidase (GUS) expression driven with different promoter constructs was quantitatively and histologically compared
in peanut leaf tissue following microprojectile bombardment. X-Gluc staining patterns varied with the construct used. Tissues
bombarded with the pAC2GUS construct had larger foci and a greater percentage of area staining blue. pEmuGN exhibited the
greatest numbers of blue spots compared to pAC2GUS and pTRA140. Histological evaluations of blue staining foci showed a diffusion
gradient of blue precipitate from a central, prominently-staining cell outward to as many as seven cell layers. The intensity
of X-gluc product in centrally-staining cells varied. Gold microprojectile particles were usually located within the three
surface cell layers. Depending on the plasmid construct, 72–90% of the centrally-staining cells had at least one gold particle.
However, the presence of GUS expression did not appear to require a microprojectile within the nucleus, which was observed
in 37% or fewer of the centrally-staining cells. With the pAC2GUS construct, staining patterns varied with location within
leaflets and had an “edge effect,” i.e., blue spots were frequently larger at the margin versus central regions. This enhanced
activity could be anticipated with an actin promoter in the more mitotically active marginal leaf cells. Total GUS activity
as determined by fluorometric analyses was correlated with the percentage of X-gluc stained area. The pAC2GUS construct exhibited
the highest total GUS activity among the three constructs. 相似文献
189.
Margaret K. Pratten Ruth Duncan Hazel C. Cable Reiner Schnee Helmut Ringsdorf John B. Lloyd 《Chemico-biological interactions》1981,35(3):319-330
The effect of DIVEMA (pyran copolymer) and three DIVEMA derivatives on the pinocytic uptake of 125I-labelled PVP and colloidal 198Au by the rat visceral yolk sac and by rat peritoneal macrophages was studied in vitro. Contrary to expectations from some earlier data, there was no enhancement of pinocytosis and in some cases inhibition was seen. [14C]DIVEMA and 125I-labelled DIVEMA were accumulated rapidly by rat peritoneal macrophages, the results indicating that this is by an adsorptive pinocytic mechanism. 相似文献
190.