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141.
142.
Alchemilla austriaca is a new species which belongs to the group ofA. demissa, A. frigens, A. longana, A. longiuscula, A. semisecta, andA. sinuata. The holotype specimen as well as leaf and flower details are illustrated (Figs. 1–3). A complete character analysis is given, differences and similarities of allied species are presented in two tables, and the position of the group within the genus is discussed.A. austriaca so far is known only from the Austrian Alps and mainly from the central ranges (distribution map: Fig. 4). Its wet subalpine and alpine habitats are characterized by species lists. 相似文献
143.
Árpád Németh 《Histochemistry and cell biology》1978,59(2):149-151
Summary Birefringence and fluorochrome lipid staining with benzpyrene are demonstrated as simple morphological methods to reveal the presence or absence of surfactant lipids in human newborn lung tissue. Lack of lipid birefringence proves to be an associated finding in the lungs of premature infants with hyaline membrane disease, indicating the possible pathogenetical importance of surfactant deficiency. 相似文献
144.
Otto Fröhlich 《The Journal of membrane biology》1982,65(1-2):111-123
Summary The interaction between chloride and the anion transport inhibitor DNDS (4,4-dinitro stilbene-2,2-disulfonate) at the external anion binding site of the human erythrocyte anion transporter was examined by two techniques: a) chloride tracer flux experiments in the presence of varying concentrations of DNDS, and b) DNDS equilibrium binding experiments in the presence of varying concentrations of intracellular and extracellular chloride, Cl
i
and Cl
o
. DNDS inhibited competitively the Cl
o
-stimulated chloride efflux from intact red cells at 0°C and pH 7.8 with an inhibitor constant of 90nm. Under the same conditions DNDS bound reversibly to one class of binding sites on intact cells with a capacity of 8.5×105 molecules/cell. Cl
o
competitively inhibited DNDS binding with an inhibitor constant of 6mm. In the absence of Cl
o
the DNDS binding constant was 84mm. The competition between chloride and DNDS was also tested in nystatintreated cells in which Cl
o
always equaled Cl
i
. Under these conditions the values of the DNDS binding constant and the chloride inhibitor constant were significantly larger. All these data were in quantitative agreement with a single-site, alternating access kinetic scheme with ping-pong-type kinetics that we have previously developed for modeling chloride exchange transport. The data also served to rule out special cases of an alternative two-sited sequential-type kinetic scheme. DNDS binding experiments were also performed at 10 and 20°C. We found that neither the DNDS binding constant nor the Cl
o
inhibitor constant were significantly changed compared to 0°C. 相似文献
145.
Hans R. Gislerød 《Plant and Soil》1982,69(3):445-456
Summary The air content in three types of propagation media, Jiffy-7 and Jiffy-9 which are Sphagnum peat and Grodan which is rockwool,
were investigated when they were held at moisture tensions of 0,6 and 12 cm measured from the base of the media. At 0 cm tension
the air content (vol. %) was highest in Jiffy-9 and lowest in Jiffy-7. At 12 cm tension the air content was higher in Grodan
than in Jiffy-9 and Jiffy-7.
Oxygen diffusion coefficients (ODC) and oxygen diffusion rates (ODR) were measured at the different air contents. At air contents
below 20 vol. % ODC was about the same for Jiffy-9 and Grodan but at air contents above 20 vol.% it was larger for Jiffy-9
than for Grodan. The oxygen diffusion rate was measured at 0, 4 and 8 cm moisture tension. At all tensions it was approximately
20% higher in Jiffy-9 than in Grodan and Jiffy-7. The ODR in Jiffy-7 and Grodan were affected equally at the same tension,
although Grodan contained more air.
Report no 253 相似文献
146.
Elastosis, the significant increase of elastic tissue, was identified by histochemical methods in 45 (53.5%) cases of an unselected series of breast cancers. They were all invasive ductal carcinomas with or without tubular differentiation. The highest proportion of tumors with elastosis was found in the "scirrhous" type of carcinomas. Elastosis was preponderantly of the focal variety, periductal and perivenous. The affected ducts were of large calibre, containing a normal, benign hyperplastic or carcinomatous epithelium. There were not observed correlations with the grade of malignancy and the extent of axillary lymph node metastases. 相似文献
147.
Effect of carbon source on the accumulation of cytochrome P-450 in the yeast Saccharomyces cerevisiae. 总被引:3,自引:0,他引:3
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The appearance of cytochrome P-450 in the yeast Saccharomyces cerevisiae depended on the substrate supporting growth. Cytochrome P-450 was apparent in yeast cells grown on a strongly fermentable sugar such as D-glucose, D-fructose or sucrose. When yeast was grown on D-galactose, D-mannose or maltose, where fermentation and respiration occurred concomitantly, cytochrome P-450 was also formed. The cytochrome P-450 concentration was maximal at the beginning of the stationary phase of the culture. Thereafter the concentration decreased, reaching zero at a late-stationary phase. When the yeast was grown on a medium that contained lactose or pentoses (L-arabinose, L-rhamnose, D-ribose and D-xylose), cytochrome P-450 did not occur. When a non-fermentable energy source (glycerol, lactate or ethanol) was used, no cytochrome P-450 was detectable. Transfer of cells from D-glucose medium to ethanol medium caused a slow disappearance of cytochrome P-450, although the amount of the haemoprotein still continued to increase in the control cultures. Cytochrome P-450 appeared thus to accumulate in conditions where the rate of growth was fast and fermentation occurred. Occurrence of this haemoprotein is not necessarily linked, however, with the repression of mitochondrial haemoprotein synthesis. 相似文献
148.
The prenatal effects of mycotoxins were investigated in GBA mice given by stomach tube a single dose of either aflatoxin B1 (4 mg/kg), ochratoxin A (8 mg/kg) or zearalenone (20 mg/kg) on pregnancy day 8 or 9. Aflatoxin caused foetal anomalies (exencephaly, open eyes, and protrusion of intestines) after exposure on gestation day 8 but not on day 9. The effects (increased prenatal mortality, reduced foetal growth, and a wide variety of malformations) caused by ochratoxin were much more severe and occurred after treatment on either of the 2 days of gestation. Among the spectrum of malformations, predominantly involving the craniofacial complex and the axial skeleton, the most striking was the total aplasia/dysplasia of the upper facial structures. These defects were always accompanied by exencephaly and anophthalmia. Zearalenone caused no effects. It is concluded that of the 3 mycotoxins screened with the technique used, ochratoxin is the most potent teratogen in mice. 相似文献
149.
Dominique Weil Nguyen Van-Cong Catherine Finaz R. Rebourcet Chantal Cochet J. de Grouchy J. Frézal 《Human genetics》1977,36(2):205-211
Summary 22 independent man-hamster (HGPRT–) hybrids using male human cells with balanced reciprocal translocation t(X;2)(p22;q32) were analysed for human genes localized on chromosome 2 (IDHS, MDHS), on chromosome X (PGK, GAL, G6PD) and for the different chromosomes in relation with the balanced reciprocal translocation (chr.2, chr.2q–, chr.Xp+).The following results were obtained:The chromosomes 2 and 2q– are absent in the 22 hybrids.In 9 hybrids, the absence of MDHS in spite of the presence of the chromosome Xp+ indicates that the gene for MDHS is not localized on this chromosome (or that the gene for MDHS is not on the segment 2q32-2qter translocated on X).In 14 hybrids, the three markers of X (PGK, GAL, G6PD) and IDHS are expressed in the presence of the chromosome Xp+. This result indicates that the genes for these markers are on Xp+ or that the genes PGK, GAL, G6PD are on X without the Xp22-Xter segment, translocated on the chr.2, and that the gene for IDHS is on the 2q32-2qter segment translocated on X.In 8 hybrids, in the absence of the intact chromosome Xp+, the higher percentage of the presence of G6PD (7 hybrids) and the lower percentage of the presence of IDHS (3 hybrids) are explained by the fact that these hybrids selected in HAT medium had to retain a segment of Xp+ bearing the human gene HGPRT. G6PD appeared very close to HGPRT and IDHS very distant from HGPRT.The study of the different correlations between the presence and the absence of these four markers on Xp+ in the different hybrids indicates the following order on the chromosome Xp+ from p to q: IDHs — PGK — GAL — G6PD.
Groupe INSERM: Directeur J. Frézal
Groupe CNRS, ER, 149: Directeur J. de Grouchy 相似文献
Groupe INSERM: Directeur J. Frézal
Groupe CNRS, ER, 149: Directeur J. de Grouchy 相似文献
150.
A.J.v.d. Broek A.I.A. Broess M.J.v.d. Heuvel H.P. de Jongh J. Leemhuis K.H. Schonemann J. Smits J. de Visser N.P. van Vliet F.J. Zeelen 《Steroids》1977,30(4):481-510
Using the strategy based on the Hansch method which analyses effects of substituents on biological activity in terms of their hydrophobic, electronic and steric effects we selectively synthesised a series of 11β-substituted-17α-ethynyl-4-estren-17β-ols that combine ease of synthesis with good discrimination between these factors aiming at finding the compounds with optimum biological activity in that series. The compounds were tested quantitatively in the Clauberg test (rabbit) and the ovulation inhibition test (rat). The differences in biological activity could reasonably be correlated with two steric effects introduced by the 11β-substituent. These were a change in the overall shape of the 11β-substituent and the angular methyl group, and direct steric hindrance of the steroid-receptor protein binding. Some exceptions were found possibly due to metabolic conversion of these compounds to the corresponding 11β-substituted-17α-ethynyl-l,5,5(10)-estratriene-5, 17β-diols. 相似文献