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1.
L Chrobák D Radochová K Smetana F Mat?ja M Kout J Polák P Dít? J Pribrosky I Dvorácková 《Folia haematologica (Leipzig, Germany : 1928)》1980,107(4):628-640
These siblings of a Czech family aged 21, 19 and 6 years, respectively, with congenital dyserythropoietic anemia, type II, (HEMPAS) are reported. In two elder siblings ferrokinetic studies revealed a rapid plasma 59Fe clearance, markedly decreased erythrocyte incorporation and shortened 51Cr red-cell survival. Direct anti-globulin test was found positive in one of them. Further investigations revealed low values of blood plasma cholesterol, total lipids, beta-lipoproteins, beta-carotine and vitamin E and A as well as low values of the prothrombin complex. Liver biopsy demonstrated siderosis and disseminated intravascular coagulation in the liver in both patients. The possible reasons for these humoral aberrations are discussed. 相似文献
2.
Late Quaternary climate change,relict populations and present‐day refugia in the northern Atacama Desert: a case study from Quebrada La Higuera (18° S)
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3.
Absence of polymorphism between HLA-B27 genomic exon sequences isolated from normal donors and ankylosing spondylitis patients 总被引:6,自引:0,他引:6
Ninety percent of individuals with ankylosing spondylitis (AS) express HLA-B27. To determine if HLA-B27 coding sequences from normal vs AS individuals show differences that might relate to the etiology of the disease, the gene coding for this allele was cloned from three different partial genomic libraries. These libraries were made with DNA from three different cell lines expressing HLA-B27: MRWC (HLA-B27, 14), obtained from an AS patient; KCA (HLA-B27, w44), obtained from a known normal individual; and MVL (HLA-B27, 27), a homozygous consanguineous cell line of unknown origin. To increase the number of clones coding for the HLA-B locus, partial libraries were made using a complete Eco RI digestion of genomic DNA in the lambda vector 607. The libraries were screened with two probes; one probe hybridizes to all HLA-A, B, C class I genes, and the other to a small subpopulation of class I genes, including the B locus. DNA from clones hybridizing with both probes was transfected into murine L cells. Cell surface expression of HLA-B27 on murine L cells was detected with a polymorphic monoclonal antibody (ME1) specific for HLA-B27, 7, 22. DNA from those clones positive for HLA-B27 by transfection was subcloned into the Xba I site of M13mp18 and the DNA sequence for exons 2 through 4 (encoding domains alpha 1, alpha 2, and alpha 3) was determined by the dideoxy technique by using synthetic oligonucleotide primers or the M13 primer. The resulting sequences show no difference between HLA-B27 alpha 1, alpha 2, alpha 3 domains from a known AS patient and a known normal individual. 相似文献
4.
An interstitial duplication of the X chromosome in a male allows physical fine mapping of probes from the Xq13-q22 region 总被引:8,自引:2,他引:6
F. P. M. Cremers R. A. Pfeiffer T. J. R. van de Pol M. H. Hofker T. A. Kruse B. Wieringa H. H. Ropers 《Human genetics》1987,77(1):23-27
Summary An insertional translocation into the proximal long arm of the X chromosome in a boy showing muscular hypotony, growth retardation, psychomotor retardation, cryptorchidism, and Pelizaeus-Merzbacher disease (PMD) was identified as a duplication of the Xq21–q22 segment by employing DNA probes. With densitometric scanning for quantitation of hybridization signals, 15 Xq probes were assigned to the duplicated region. Analysis of the duplication allowed us to dissect the X-Y homologous region physically at Xq21 and to refine the assignments of the loci for DXYS5, DXYS12, DXYS13, DXS94, DXS95, DXS96, DXS111, and DXS211. Furthermore, we demonstrated the presence of two different DXYS13, and DXS17 alleles in genomic DNA of our patient, suggesting that the duplication resulted from a meiotic recombination event involving the two maternal X chromosomes. 相似文献
5.
Chromosome aberrations and sister-chromatid exchanges (SCEs) were analyzed in short-term cultures of peripheral lymphocytes of 44 workers occupationally exposed to mancozeb during the production of the pesticide Novozir Mn80 and 30 control persons. The results suggest that mancozeb exposure was associated with a significant increase in the frequencies of cells with structural chromosome aberrations (2.07% vs. 1.10% in the controls), and the number of SCEs per cell (9.19 +/- 1.81 vs. 7.82 +/- 1.04 in the controls). 相似文献
6.
Regulation of cytosolic aspartate aminotransferase mRNAs in the Fao rat hepatoma cell line by dexamethasone, insulin and cyclic AMP 总被引:2,自引:0,他引:2
R Barouki M Pavé-Preux B Bousquet-Lemercier S Pol J Bouguet J Hanoune 《European journal of biochemistry》1989,186(1-2):79-85
Glucocorticoid hormones increase the activity of cytosolic aspartate aminotransferase (cAspAT) in the Fao rat hepatoma cell line. Maximal increase (6-10-fold) was observed 48 h following the addition of the glucocorticoid agonist dexamethasone at a concentration of 0.1 microM. The effect of dexamethasone was specific since it was not mimicked by sex steroids and was inhibited by the glucocorticoid antagonist RU 486. Insulin (0.1 microM) inhibited by more than 50% the induction of cAspAT by glucocorticoids. The cAMP analog, 8-bromoadenosine 3',5'-monophosphate (Br8cAMP, 0.5 mM), potentiated the effect of dexamethasone (2-3-fold) and partially relieved the inhibitory effect of insulin on the induction by dexamethasone. Both insulin and Br8-cAMP had no significant effect on basal activity. The mitochondrial isoenzyme was insensitive to the various hormonal treatments. Northern blot analysis revealed the presence of two major (2.1-kb and 1.8-kb) and one minor (4-kb) mRNA species hybridizing with a rat cAspAT probe. The regulation of these mRNAs by glucocorticoids, insulin and cAMP correlated with the variation of the cAspAT activity, suggesting that these hormones act at the pretranslational level. We compared the regulation of cAspAT mRNAs with those of tyrosine aminotransferase mRNA. Both were similarly increased by dexamethasone but the latter was also increased by cAMP even in the absence of the glucocorticoid agonist. In addition, the increase in tyrosine aminotransferase mRNA was inhibited by cycloheximide whereas the increase in cAspAT mRNAs was not. These results show that there are significant differences in the regulation of cAspAT and tyrosine aminotransferase by glucocorticoids and other hormones, although both enzymes probably contribute to the same metabolic pathway. 相似文献
7.
Methanogenesis in an Upflow Anaerobic Sludge Blanket Reactor at pH 6 on an Acetate-Propionate Mixture 总被引:8,自引:4,他引:4
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Erik ten Brummeler Look W. Hulshoff Pol Jan Dolfing Gatze Lettinga Alexander J. B. Zehnder 《Applied microbiology》1985,49(6):1472-1477
High-rate anaerobic digestion can be applied in upflow anaerobic sludge blanket reactors for the treatment of various wastewaters. In upflow anaerobic sludge blanket reactors, sludge retention time is increased by a natural immobilization mechanism (viz. the formation of a granular type of sludge). When this sludge is cultivated on acid-containing wastewater, the granules mainly consist of an acetoclastic methanogen resembling Methanothrix soehngenii. This organism grows either in rods or in long filaments. Attempts to cultivate a stable sludge consisting predominantly of Methanosarcina sp. on an acetate-propionate mixture as substrate by lowering the pH from 7.5 during the start-up to approximately 6 failed. After 140 days of continuous operation of the reactor a filamentous organism resembling Methanothrix soehngenii prevailed in the sludge. The specific methanogenic activity of this sludge on acetate-propionate was optimal at pH 6.6 to 6.8 and 7.0 to 7.2, respectively. 相似文献
8.
Permanent suppression of phase separation cataract in calf lens using amine modification agents 总被引:2,自引:0,他引:2
R J Siezen C M Coppin G B Benedek 《Biochemical and biophysical research communications》1985,133(1):239-247
Low temperature induced opacification (cold cataract) of the nucleus of young mammalian lenses is associated with a phase separation of proteins in the lens cell cytoplasm. Calf lenses were treated with a variety of imido-esters and N-hydroxysuccinimide-esters, which react specifically with amino groups. Many potent inhibitors of phase separation cataract were identified which lower the opacification temperature by 6 degrees C or more. Lenses generally remain clear, colorless and soft. Furthermore, suppression of the cold cataract temperature is permanent upon removal of excess reagent. 相似文献
9.
Vigh B. Vigh-Teichmann I. Manzano e Silva M. J. van den Pol A. N. 《Cell and tissue research》1983,230(3):615-630
Cell and Tissue Research - Cerebrospinal fluid (CSF)-contacting neurons were studied by means of electron microscopy in the spinal cord and/or terminal ventricle of the ray, Raja clavata... 相似文献
10.
Ultrathin sections were prepared from the tissues of lettuce leaves with mosaic-like symptoms and thickened nervature which were studied by means of electron microscopy. Intracellular inclusions surrounded by a membrane were found in the cytoplasm of parenchym cells of the investigated lettuce leaves(Lactuca saliva L. provar.capitata L. nid.jaggeri Helm., cv. Pra?an). Crystals with a distinctly apparent hexagonal lattice could be observed in the inclusions. No crystal containing inclusions were found in the tissues from the leaves without mosaic-like symptoms and in those from thickened nervature. 相似文献