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1.
Summary Considerably higher thyroxine and triiodothyronine concentrations in sera of bovine fetuses than in maternal samples were found during the last trimester of pregnancy.Acknowledgment. We wish to thank Miss.R. Fajkoová for skilled technical assistance.  相似文献   

2.
Solvent extraction of serum and other biological fluids at an acidic pH is a convenient method to remove the insulin-like growth factor binding proteins (IGFBPs); however, an incomplete removal of IGFBPs can occur and this can potentially interfere with the radioimmunoassay of insulin-like growth factors (IGFs). This study compared the removal of IGFBPs from normal adult rat serum and 5-day old neonatal rat serum by acid-gel filtration, and three solvent extraction methods, i.e., acid-ethanol (AE), acid-cryo-ethanol (ACE) and formic acid-acetone (FAA) treatments by western ligand blotting and slot-blotting analysis. In adult rat serum all three extraction methods removed nearly 75% of total IGFBPs present. For the neonatal serum, AE and FAA were very inefficient in eliminating the IGFBPs, while ACE was somewhat better, as it removed nearly 30% of IGFBPs. Ligand blots of extracted samples showed that IGFBPs of lower size range, 24 to 32 kDa (IGFBP-4, IGFBPs-1 and-2), were resistant to solvent extraction. Acid-gel filtration, in contrast, eliminated >95% of IGF-binding components in both sera. Determination of IGF-I concentrations in samples after gel filtration and extraction methods revealed lower IGF-I values in neonatal serum in acid extracted samples. These data caution against using solvent extractions for IGFBP removal in fetal/neonatal serum.  相似文献   

3.
Mice infected with non-capsulated Staphylococcus aureus strains highly resistant to methicillin survived after the administration of specific immunoglobulin extracted from pooled human sera by using homologous capsular type strains, but no protective effect was shown with a conventional immunoglobulin preparation and methicillin, even with high doses.  相似文献   

4.
Summary Mice infected with non-capsulatedStaphylococcus aureus strains highly resistant to methicillin survived after the administration of specific immunoglobulin extracted from pooled human sera by using homologous capsular type strains, but no protective effect was shown with a conventional immunoglobulin preparation and methicillin, even with high doses.  相似文献   

5.
Anti-idiotypic sera were obtained in Rabbits immunized with Rh antibodies (isolated from the serum sample collected in 1974 from a Blood Donor). The sera agglutinate, at high titers, red cells coated with the immunizing antibodies and, at different titers, cells coated with antibodies from serum samples taken at other periods. Inhibition of hemagglutination of anti-idiotypic sera by different samples from the same Donor was complete with the immunizing serum and partial with other samples. These results show that idiotypes or idiotypic specificities appeared or disappeared during the period studied and represent the first observation on evolution of antibody idiotypy in Man.  相似文献   

6.
Sera from different mammalian species displayed great differences in mitogenic activity, as measured by stimulation of DNA synthesis in BALB/c 3T3 cells (3T3 cells). Among the sera examined, fetal bovine serum was least active, and increasing activity was detected in calf serum, human serum, rat serum and mouse serum, in that order. Rat and mouse sera exhibited extremely high mitogenic activity with 3T3 cells, but when TIG-1 human fetal lung fibroblasts were used for the DNA assay instead, the activity levels of all of the sera were lower, and the differences between them were smaller. To determine the reasons for these differences, the heparin-binding growth factors in each serum were separated on a heparin affinity column. Five peaks of DNA-stimulating activity were obtained. Three of these were found in all sera examined, with both 3T3 cells and TIG-1 cells. Two other peaks were found only with 3T3 cells; one was peculiar to rat and mouse sera, with extremely high activity in the rat, and the other was specific to fetal serum. The dependence of the activity of these peaks on the cells used for the test was confirmed using normal rat lung fibroblasts and immortalized rat kidney cells. These findings adequately explain the species-specific differences in mitogenic activity of whole sera, and the variation in activity depending on the cells used for assay of DNA synthesis.  相似文献   

7.
Summary The activities of collagenase-like peptidase, estimated by using (succinyl-Gly-Pro-Leu-Gly-Pro-Leu-Gly-Pro)-4-methyl-coumaryl-7-amide as substrate, and of dipeptidyl-aminopeptidase IV were decreased in the sera from patients with rheumatoid arthritis. Both enzymes bring about the degradation of peptides derived from collagen. A significant positive correlation was observed between the activities of the two serum peptidases.  相似文献   

8.
Sera from different mammalian species displayed great differences in mitogenic activity, as measured by stimulation of DNA synthesis in BALB/c 3T3 cells (3T3 cells). Among the sera examined, fetal bovine serum was least active, and increasing activity was detected in calf serum, human serum, rat serum and mouse serum, in that order. Rat and mouse sera exhibited extremely high mitogenic activity with 3T3 cells, but when TIG-1 human fetal lung fibroblasts were used for the DNA assay instead, the activity levels of all of the sera were lower, and the differences between them were smaller. To determine the reasons for these differences, the heparin-binding growth factors in each serum were separated on a heparin affinity column. Five peaks of DNA-stimulating activity were obtained. Three of these were found in all sera examined, with both 3T3 cells and TIG-1 cells. Two other peaks were found only with 3T3 cells; one was peculiar to rat and mouse sera, with extremely high activity in the rat, and the other was specific to fetal serum. The dependence of the activity of these peaks on the cells used for the test was confirmed using normal rat lung fibroblasts and immortalized rat kidney cells. These findings adequately explain the species-specific differences in mitogenic activity of whole sera, and the variation in activity depending on the cells used for assay of DNA synthesis.  相似文献   

9.
The activities of collagenase-like peptidase, estimated by using (succinyl-Gly-Pro-Leu-Gly-Pro-Leu-Gly-Pro)-4-methylcoumaryl-7-amide as substrate, and of dipeptidyl-aminopeptidase IV were decreased in the sera from patients with rheumatoid arthritis. Both enzymes bring about the degradation of peptides derived from collagen. A significant positive correlation was observed between the activities of the two serum peptidases.  相似文献   

10.
Tranfer of (14C)-gal from exogenous UDP(14C)-gal has been demonstrated with ovomucoid as glycoprotein acceptor in ascitic fluid sera from Balb/c mice bearing isogenic YC8 tumor. Transfer exists without ovomucoid, in great ratio in ascitic fluid and in sera from ascitic mice too, showing occurrence of endogenous acceptors, the origin of which has to be proved.  相似文献   

11.
M K Feldman 《Experientia》1978,34(1):97-98
Monolayer cultures of normal, preneoplastic and neoplastic murine mammary epithelial cells were exposed to various types of mammalian serum. A progressive decline in levels of thymidine incorporation together with a change in the ordering of sera which stimulates optimal incorporation was observed in the transformed cells.  相似文献   

12.
The primary objective of this review was to assess the size and consistency of Royal Jelly (RJ) effect on serum lipids in experimental animals and humans. The data from animal studies were pooled, where possible, and statistically evaluated by Student's t-test. Meta-analysis was used for the evaluation of human trials. It was found that RJ significantly decreased serum and liver total lipids and cholesterol levels in rats and rabbits and also retarded the formation of atheromas in the aorta of rabbits fed a hyperlipemic diet. Meta-analysis of the controlled human trials of RJ to reduce hyperlipidemia showed a significant reduction in total serum lipids and cholesterol levels and normalization of HDL and LDL as determined from decrease in β/α lipoproteins. The best available evidence suggests that RJ at approximately 50 to 100 mg per day, decreased total serum cholesterol levels by about 14%, and total serum lipids by about 10% in the group of patients studied.  相似文献   

13.
Follow-up investigation of the blood sera from preparturient women and women with habitual abortions showed the presence of a factor which has an activating effect on smooth muscle preparations because it causes the release of prostaglandins. Gel-chromatographic counter flow separation and microelectrophoresis of the blood sera have shown that the isolated serum factor is a water soluble glycopeptide with a molecular weight of about 2000.  相似文献   

14.
C E Steele 《Experientia》1985,41(12):1601-1603
A comparison was made between the development of post-implantation rat embryos in human serum and rat serum. Protein synthesis (growth) and somite number (differentiation) were retarded in human serum and there was an increased frequency of neural tube defects. Male and female human sera supported development equally well.  相似文献   

15.
Summary A comparison was made between the development of post-implantation rat embryos in human serum and rat serum. Protein synthesis (growth) and somite number (differentiation) were retarded in human serum and there was an increased frequency of neural tube defects. Male and female human sera supported development equally well.  相似文献   

16.
Summary Follow-up investigation of the blood sera from preparturient women and women with habitual, abortions showed the presence of a factor which has an activating effect on smooth muscle preparations because it causes the release of prostaglandins. Gel-chromatographic counter flow separation and microelectrophoresis of the blood sera have shown that the isolated serum factor is a water soluble glycopeptide with a molecular weight of about 2000.  相似文献   

17.
Conclusions Our results indicate that the choice of the probe for ELOSA is of major concern. In our panel we had seven sera which contained about 100 molecules/ml and further five sera which contained less than 1000 molecules/ml. Most of them were detected by the long probe but not by the short probe. When PCR for the S-or PreS-gene was included it was possible to detec all 24 HBV-positive sera (not shown) by ELOSA. The reliable lower quantification limit for the long probe is 250 molecules/ml and for the short probe 2500 molecules/ml. Surprisingly, chemiluminescence did not produce better qualitative or quantitative results. The data suggest that the usage of several replicates allows relative quantification in most cases. One possible drawback we see is the hybridization efficiency. Six of our positive samples showed great differences between the number of target molecules suggested by agarose gel electrophoreses or by hybridization (Southern blot or ELOSA). All of them contained more than 106 molecules/ml. For these cases and for the samples where the short probe and the long probe gave discordant result (2 cases) we think that competitive PCR will be the method of choice, but in most cases ELOSA with the long probe gives reliable results and is highly sensitive.  相似文献   

18.
Summary WhenNaegleria fowleri (Lee) was incubated in newborn calf and human serum an amebicidal effect was observed. Heat inactivation of both sera resulted in the recovery of viable amebae after incubation in these sera. Exogenous iron added to non-heat inactivated calf serum improved viability slightly but was without effect when added to human serum not heat inactivated. Exogenous iron greatly enhanced growth and/or viability in heat inactivated calf serum. Viability of amebae also was considerably enhanced in human serum which was heat inactivated when pH was lowered in conjunction with iron supplements.Appreciation is expressed to Dr Ronald R. Weik (Dept. Biochemistry, Louisiana State Univ., New Orleans, LA. 70119) and Dr David T. John (Dept. Microbiology, Medical College of Virginia, Richmond, VA. 23298) for providing theNaegleria fowleri (Lee) used in this investigation.  相似文献   

19.
Summary Acini were enzymatically dissociated from rat submandibular gland and their mucous glycoproteins radiolabelled with14C-glucosamine. Sera from cystic fibrosis patients stimulated the release of labelled TCA/PTA — insoluble material from the cultured acinar cells to a significantly higher degree than did control sera.This work was supported by the Canadian Cystic Fibrosis Foundation and the Sellers Foundation.  相似文献   

20.
D Berger  T L Vischer  A Micheli 《Experientia》1983,39(10):1109-1111
Using casein plates as a sensitive assay for proteolytic activity, it was observed that sodium-dodecyl sulfate (SDS) and other anionic detergents induce caseinolysis when mixed with sera and plasma. Caseinolysis was dependent on the presence of plasminogen in the fluids and could be blocked by inhibitors of serine proteases and antibody to plasminogen. Similarly, organic solvents such as isopropanol induced caseinolysis after mixing with plasma, but not normal serum. Isopropanol dissociated complexes of alpha 1-antitrypsin or alpha 2-macroglobulin with trypsin preformed in vitro. As both SDS and organic solvents are widely used in biochemical investigations of biological fluids, attention should be paid to the possible induction of proteolysis.  相似文献   

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