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排序方式: 共有170条查询结果,搜索用时 15 毫秒
41.
R C Montes Pérez R I Rodríguez Vivas J F Torres Acosta L G Ek Pech 《Revista de biología tropical》1998,46(3):821-827
Gastrointestinal parasites, and egg and oocyst output in the faeces of captive white-tailed deer (Odocoileus virginianus yucatanensis) were recorded in Yucatan, Mexico. Feces were obtained from from January through December 1995 (ten samples every two weeks per place). Samples were processed by flotation and the McMaster techniques. Faecal cultures for L3 larvae were made by the Corticelli-Lai technique. Oocysts in faeces were cultured in 2% potassium dicromate. Seven genera were determined (Haemonchus spp., Cooperia spp, Isospora spp., Eimeria spp., Trichuris spp., Strongyloides spp. and Moniezia spp.) which represent five orders. The most frequent genera were Haemonchus, Isospora and Eimeria. The genus Isospora is reported for the first time in deer of this region, although it was not possible to explain the source of this parasite. The frequency and level of faecal egg and oocyst outputs were variable during the year and increased during the rainy season. There was a positive correlation between relative humidity, environmental temperature and rainfall with the coccidia and strongylida orders. In the central zone of Yucatan the meteorological conditions during the rainy season are favourable for the development of gastrointestinal parasitism which enable an increased risk of infection for deer. 相似文献
42.
Pia Ek Gunilla Pettersson Bo Ek Feng Gong Jin-Ping Li Orjan Zetterqvist 《European journal of biochemistry》2002,269(20):5016-5023
Protein histidine phosphorylation in eukaryotes has been sparsely studied compared to protein serine/threonine and tyrosine phosphorylation. In an attempt to rectify this by probing porcine liver cytosol with the phosphohistidine-containing peptide succinyl-Ala-His(P)-Pro-Phe-p-nitroanilide (phosphopeptide I), we observed a phosphatase activity that was insensitive towards okadaic acid and EDTA. This suggested the existence of a phosphohistidine phosphatase different from protein phosphatase 1, 2A and 2C. A 1000-fold purification to apparent homogeneity gave a 14-kDa phosphatase with a specific activity of 3 micro mol.min-1.mg-1 at pH 7.5 with 7 micro m phosphopeptide I as substrate. Partial amino-acid sequence determination of the purified porcine enzyme by MS revealed similarity with a human sequence representing a human chromosome 9 gene of hitherto unknown function. Molecular cloning from a human embryonic kidney cell cDNA-library followed by expression and purification, yielded a protein with a molecular mass of 13 700 Da, and an EDTA-insensitive phosphohistidine phosphatase activity of 9 micro mol.min-1.mg-1 towards phosphopeptide I. No detectable activity was obtained towards a set of phosphoserine-, phosphothreonine-, and phosphotyrosine peptides. Northern blot analysis indicated that the human phosphohistidine phosphatase mRNA was present preferentially in heart and skeletal muscle. These results provide a new tool for studying eukaryotic histidine phosphorylation/dephosphorylation. 相似文献
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44.
Cornelis Jakobs Eivind Solem Johan Ek Karin Halvorsen Egil Jellum 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1977,143(1):31-38
Urine and serum from patients with maple syrup urine disease (MSUD) have been examined quantitatively and qualitatively using glass capillary gas chromatography in combination with mass spectrometry. During clinical episodes, patients with this disease were found to excrete increased amounts of the following metabolites in addition to the previously recognized branched-chain 2-keto and 2-hydroxy acids, lactate and 3-hydroxybutyrate; 2-hydroxybutyrate, 2-hydroxyisobutyrate, 3-hydroxyisovalerate, 3-hydroxylsobutyrate and 2-methyl-3-hydroxybutyrate. Most of the latter compounds seem to accompany ketoacidosis and lactic acidosis. The capillary column also separated the d- and l-forms of 2-keto-3-methylvalerate, and both isomers were, in contrast to earlier assumptions, present in the MSUD patients. The results clearly demonstrate that new information on the metabolic situation in well known disorders may be obtained by exploiting the high resolving power of capillary columns. 相似文献
45.
The Pr protein, which is one of the major equine acidic prealbumins and which consists of a large number of phenotypes, has been studied with regard to its chemical identity. Serum samples of known Pr phenotype which had been treated with varying amounts of bovine trypsin were subjected to starch gel electrophoresis at pH 4.8. When a certain amount of trypsin was used, the Pr protein was markedly affected, whereas the other acidic prealbumins retained their normal electrophoreitic pattern. Extracts from three different regions of the acidic prealbumin field were tested by the casein precipitating inhibition test (CPI-test). Marked antitrypsin effect appeared against the extract from the Pr zone but not against the extracts from the two other acidic prealbumin zones. When acidic starch gel electrophoresis was combined with the CPI-test, a broad inhibitory zone appeared in the area of the Pr proteins. Pr protein was isolated by the use of agarose gel electrophoresis and sepharose column chromatography. The isolated protein which was tested for purity by gel electrophoresis had a molecular weight of about 60,000. It is concluded that the equine Pr protein corresponds to αi-antitrypsin. 相似文献
46.
Dziegielewska KM Møller JE Potter AM Ek J Lane MA Saunders NR 《Cell and tissue research》2000,299(3):335-345
The nervous and the immune systems share several molecules that control their development and function. We studied the temporal and spatial distribution of the immunoreactivity of two acute-phase cytokines, TNF-alpha and IL-1beta, in the developing sheep neocortex and compared it with the well-described distribution of fetuin, a fetal glycoprotein also known to modulate the production of cytokines by lipopolysaccharide (LPS)-stimulated monocytes and macrophages. TNF-alpha was present first at embryonic day 30 (E30) (term is 150 days in sheep) as a faint band of immunoreactivity between the ventricular zone and the primordial plexiform layer (preplate). IL-1beta was detected at the first appearance of the cortical plate (E35-E40). Both cytokines were present on both sides of the cortical plate, which contained fetuin-positive cells, but was free from cytokine staining. By E60, TNF-alpha immunoreactivity was less prominent than that of IL-1beta and was confined to the marginal zone and outer developing white matter; IL-1beta was present in the marginal zone and in two bands of immunoreactive cells, one at the border of the cortical plate/developing layer VI (cells of neuronal morphology) and the other at the border of layer V and the developing white matter (identified as microglia). By E80, TNF-alpha staining had disappeared and IL-1beta-immunopositive microglia were no longer detectable. By E100-E140 only a few immunoreactive cells were identified in layers V-VI; these did not co-localize with fetuin-positive cells. The differences in distribution between fetuin and the two cytokines suggest that the opsonizing role of fetuin, proposed for monocyte production of cytokines, is probably not present in the developing brain. However, early in neocortical development TNF-alpha and IL-1beta were present in the subplate zone at a time of intense synaptogenesis. 相似文献
47.
Leptin ameliorates burn-induced multiple organ damage and modulates postburn immune response in rats 总被引:13,自引:0,他引:13
Cakir B Cevik H Contuk G Ercan F Ekşioğlu-Demiralp E Yeğen BC 《Regulatory peptides》2005,125(1-3):135-144
The present study was designed to determine whether exogenous leptin reduces remote organ injury in the rats with thermal burn trauma. Leptin (10 microg/kg) or saline was administered intraperitoneally after burn injury, and the rats were decapitated at either 6 or 24 h. Plasma samples of 24-h burn group were assayed for the determination of monocyte and neutrophil apoptosis. Thermal injury increased tissue-associated myeloperoxidase (MPO) activity and microscopic damage scores in the lung, liver, stomach, colon and kidney of both 6- and 24-h burn groups. In the 6-h burn group, leptin reduced microscopic damage score in the liver and kidney only, while damage scores in the 24-h burn group were reduced in all the tissues except the lung. Also, in both burn groups, leptin reduced elevated MPO activity in all tissues except the lung. The percentage of mononuclear cells was significantly reduced at the 24 h of burn injury, while the granulocyte percentage was increased. Leptin treatment, however, had no significant effect on burn-induced reversal of white blood cell ratios. On the other hand, burn-induced increase in the death of mononuclear cells and granulocytes was significantly reduced in leptin-treated rats. The results of the present study suggest that leptin may provide a therapeutic benefit in diminishing burn-induced inflammation and associated multiple organ failure. 相似文献
48.
M. Isabel del-Val Charles G. Hill Jr. Jesús Jiménez-Barbero Cristina Otero 《Biotechnology letters》2001,23(23):1921-1924
A commercial enzyme preparation with -galactosidase and cellulase activities catalyzed the synthesis of 6-galactosyl lactose (18% yield) from lactose with a better selectivity (62%) for production of the product than thermostable enzymes and most mesophilic enzymes (32–43%). 相似文献
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50.
Abela Mpobela Agnarson Susanne Str?mdahl Francis Levira Honorati Masanja Anna Ekéus Thorson 《PloS one》2015,10(12)