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121.
Marcelo dos Santos Guerra Maria Tereza M. Nogueira 《Plant Systematics and Evolution》1990,170(3-4):229-236
Analysis of several populations in a large part of the distribution area of the genusEmilia in Brazil has revealed only two species: the diploidE. sonchifolia and the tetraploidE. fosbergii. The more widely reportedE. coccinea was not found. They show a karyotype constancy in morphology and chromosome number (2n = 10 and 2n = 20, respectively), C-banding pattern and number of secondary constrictions. Some indications were found thatE. fosbergii may be an allopolyploid and that its ancestors had different genome sizes. 相似文献
122.
Jamal Bayad Nicole Sabolovic Denyse Bagrel Athanase Visvikis Maria Wellman Gerard Siest 《Cell biology and toxicology》1990,6(2):157-170
Eighteen IgGl monoclonal antibodies (blabs) have been produced against gamma-glutamyl transferase (GGT) from rat kidney. They were specific to the light subunit of the enzyme with affinity constants ranging from 0.3 to 7.5 108 M–1, while they did not react with GGT from other sources i.e. human and pig kidney, rat and guinea pig liver, suggesting species and organ specificity. Two of the blabs (N° 11 and 21) lost their immunoreactivities towards rat kidney GGT in the presence of N-acetyl-neuraminic acid, while immunoreactivities of the other blabs were unchanged. Furthermore, Mabs No 11 and 21 did not react with desialylated rat kidney GGT. These findings suggest that N-acetyl-neuraminic acid is involved in the epitopes recognized by these two Mabs.Abbreviations ELISA
enzyme linked immunosorbent assay
- GGT
gamma-glutamyltransferase
- Mab
monoclonal antibody
- SDS-PAGE
sodium dodecyl sulfate-polyacrylamide gel electrophoresis 相似文献
123.
N. Romero C. Marsac M. Fardeau M. Droste B. Schneyder B. Kadenbach 《Histochemistry and cell biology》1990,94(2):211-215
Summary The immunohistochemical reaction of monoclonal as well as polyclonal antibodies against cytochrome c oxidase (COX) subunits
with serial sections of normal human skeletal muscle was investigated. The stronger reactivity of polyclonal antibodies to
COX subunits II–III and VIIbc with type I as compared to type II fibres, correlated well with the higher histochemical reactivity
of NADH dehydrogenase, succinate dehydrogenase and cytochrome c oxidase in type I fibres. In contrast an almost exclusive
reaction of a monoclonal antibody against subunit IV with type I fibre and a preponderan reaction of a polyclonal antibody
against subunits Vab with type II fibres was obtained. Antibodies against subuntis I, Vb and VIc did not reveal a fibre-type-specific
reactivity. The data indicate in human muscle the occurrence of fibre type-specific isozymes of cytochrome c oxidase differing
in subunits IV and Va or Vb. 相似文献
124.
Prostaglandin biosynthesis by human decidual cells: effects of inflammatory mediators 总被引:4,自引:0,他引:4
M D Mitchell S Edwin R J Romero 《Prostaglandins, leukotrienes, and essential fatty acids》1990,41(1):35-38
There is substantial evidence that decidual activation, in association with infection, is linked with the onset of both preterm and term labor. We therefore undertook the present study to evaluate prostaglandin production and its potential regulation by inflammatory mediators in human decidual cells in primary monolayer culture. Upon attaining confluence, the cells were incubated with endotoxin, interleukin 1 alpha (IL1 alpha), interleukin 1 beta (IL1 beta); or tumor necrosis factor (TNF). Production of prostaglandin (PG) E2 and PGF2 alpha was determined using specific radioimmunoassays. Endotoxin and these cytokines all induced significant concentration-dependent increases in PGE2 and PGF2 alpha production. Our results suggest that term human decidual cells are responsive to endotoxin and cytokines and that generation of these substances in the decidua or nearby (eg. in response to infection) will lead to increased prostaglandin production and uterine contractions. 相似文献
125.
Jose Jacob 《Molecular and cellular biochemistry》1988,84(1):97-103
Summary Effects of Ca2+ ionophores, A23187 and lasalocid, on superoxide anion generation by chemotactic peptide, N-formyl-methionyl-leucyl-phenylalanine methyl ester, in rabbit peritoneal exudate neutrophils were studied. The ionophores by themselves did not activate superoxide anion generation in these neutrophils. When preincubated with the cells for 2 min, both the ionophores inhibited superoxide generation induced by chemotactic peptide. The inhibition was present even in the absence of extracellular Ca2+ and the inhibition was better then. Lasalocid produces a dose-dependent chlortetracycline fluorescence decrease response in neutrophils loaded with chlortetracycline. This response is independent of extracellular Ca2+ concentration and is related to release of Ca2+ from intracellular storage sites. The dose-range at which lasalocid gives this response is same as the dose-range at which it causes inhibition of superoxide response. It may be concluded that the inhibition of superoxide generation by these ionophores is correlated to intracellular Ca2+ modulation.Abbreviations FMLP
Formyl-Methionyl-Leucyl-Phenylalanine methyl ester 相似文献
126.
Jose L. Vega Vicki L. Holmberg Edgar C. Clausen James L. Gaddy 《Archives of microbiology》1988,151(1):65-70
Intrinsic growth and substrate uptake parameters were obtained for Peptostreptococcus productus, strain U-1, using carbon monoxide as the limiting substrate. A modified Monod model with substrate inhibition was used for modeling. In addition, a product yield of 0.25 mol acetate/mol CO and a cell yield of 0.034 g cells/g CO were obtained. While CO was found to be the primary substrate, P. productus is able to produce acetate from CO2 and H2, although this substrate could not sustain growth. Yeast extract was found to also be a growth substrate. A yield of 0.017 g cell/g yeast extract and a product yield of 0.14 g acetate/g yeast extract were obtained. In the presence of acetate, the maximum specific CO uptake rate was increased by 40% compared to the maximum without acetate present. Cell replication was inhibited at acetate concentrations of 30 g/l. Methionine was found to be an essential nutrient for growth and CO uptake by P. productus. A minimum amount of a complex medium such as yeast extract (0.01%) is, however, required. 相似文献
127.
Elvira D'Alessandro Corinna De Matteis Vaccarella Maria Luisa Lo Re Francesco Cappa Angela D'Alfonso Stefania Discepoli Maria Rosa Della Penna Giuseppe Del Porto 《Human genetics》1988,80(2):203-204
Summary Pericentric inversion of chromosome 19 has been found in several members of three unrelated families from a restricted geographical region. In one of the families, an additional pericentric inversion of chromosome 9 was observed. Reproductive problems, multiple abortions in two families and a neonatal death in the third, were present. A review of previously described cases is included, and the genetic risk connected with this type of rearrangement is also discussed. 相似文献
128.
Maria Di Bello Valeria Lucchini Stefania Chiari Roberto Colleoni Nicoletta Colombo Alberto Mantovani Paola Allavena 《Cancer immunology, immunotherapy : CII》1988,27(1):63-68
Summary Expression of HLA-DR antigens by purified preparations of human ovarian carcinoma cells freshly isolated from surgical specimens was examined in parallel with the capacity of tumor cells to elicit a blastogenic response from autologous lymphocytes in mixed lymphocyte-tumor culture (MLTC) assay. Of 21 tumor preparations, 11 (52%) reacted with monoclonal antibodies 279 and/or 949 specific for a monomorphic determinant of HLA-DR antigens, with heterogeneous positivity, ranging between 30% and 95%. In this series of patients positive MLTC occurred in 8/21 individual experiments. The HLA-DR expression was proportionally similar in tumors giving positive MLTC (4/8=50%) and negative MLTC (7/13=53%). The lack of correlation between DR expression on tumor cells and stimulatory activity in autologous MLTC and the fact that DR-negative tumors could induce lymphocyte stimulation, support the hypothesis that blastogenesis occurs upon recognition of tumor-associated antigens, different from DR molecules, possibly tumor-specific antigens. 相似文献
129.
Bianca Colonna Maria Bernardini Gioacchino Micheli Francesco Maimone Mauro Nicoletti Mariassunta Casalino 《Plasmid》1988,20(3):221-231
Tn1935, a 23.5-kb transposon mediating resistance to ampicillin, kanamycin, mercury, spectinomycin, and sulfonamide was isolated from pZM3, an IncFIme virulence plasmid from Salmonella wien. Tn1935 possesses the entire sequence of Tn21 and contains two additional DNA segments of 0.95 and 2.7 kb carrying the ampicillin and kanamycin resistance genes, respectively. The latter is part of a composite element since it is flanked by two IS15-like insertion sequences (IS1936) in direct orientation. IS1936 is about 800 bp long and is closely related to IS15 delta, IS26, IS46, IS140, and IS176. Functional analysis of IS1936-mediated cointegrates shows that both insertion sequences are active and able to form cointegrates at the same frequency. Resolution of the cointegrates requires the presence of the host Rec system. The presence of the composite IS1936-element within Tn1935 supports the hypothesis that multidrug resistance transposons evolved by insertion of antibiotic determinants which are themselves transposable. 相似文献
130.
Effects of the administration of cadmium and zinc on the concentration of zinc in the thymus of rats
Paloma Huerta Paloma Galan Alberto J. Alcala Bartolome Ribas Jose M. Teijon 《Biological trace element research》1988,18(1):95-103
The zinc content of thymus glands of male Wistar rats has been determined during five weeks of treatment with ZnCl2 and CdCl2, and compared with a group of control rats. THymus gland extracts were chromatographed on columns of Sephadex G-75 and the zinc content of the one hundred fractions obtained were determined by atomic absorption spectrophotometry. The rats treated with ZnCl2 showed an increase in the thymus concentration of zinc bound to high and low molecular weight proteins. The rats treated with CdCl2 showed an increase in zinc concentration, as opposed to the control group, during the first three weeks of treatment, and thereafter show a toxic effect of cadmium on the gland, with ulterior regression of the latter, and a decrease in the concentration of zinc. 相似文献