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1.
R. J. Bosma A. J. Kwakernaak J. J. Homan van der Heide P. E. de Jong G. J. Navis 《American journal of transplantation》2007,7(3):645-652
Obesity is a risk factor for renal graft loss. Higher body mass index (BMI) in native kidneys is associated with glomerular hyperfiltration. Whether higher BMI in renal transplants is associated with hyperfiltration is unknown. We investigated the impact of BMI on renal hemodynamics 1 year post-transplant. We analyzed glomerular filtration rate (GFR, (125)I-iothalamate) and effective renal plasma flow (ERPF, (131)I-hippurate) in 838 kidney transplants. Data were analyzed for all patients and for the subpopulation without diabetes. Long-term impact of BMI and renal hemodynamics were explored by Cox-regression. With higher BMI GFR and filtration fraction (FF) increased significantly. Multivariate analysis supported impact of BMI on GFR (adjusted r(2) of the model 0.275) and FF (adjusted r(2) of the model 0.158). This association was not explained by diabetes mellitus. On Cox-regression analysis, lower GFR and higher FF were independent determinants of overall graft loss and graft loss by patient mortality. Lower GFR and higher BMI were determinants of death-censored graft loss, with borderline contribution of higher FF. In renal transplants higher BMI is independently associated with higher GFR and FF one year posttransplant, suggesting glomerular hyperfiltration with altered afferent-efferent balance. Mechanisms underlying the long-term prognostic impact of hyperfiltration deserve further exploration. 相似文献
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Microorganisms isolated from the soil and the rhizosphere of wheat plants produce growth regulating substances with effects similar to gibberellins when grown in submerse cultures. Bioassays and thin layer chromatography were used for characterization. Different plant growth regulating substances and variations in their quantity were observed among microorganisms. The amounts of gibberellin-like substances found in culture filtrates varied, in a range from 0.01 to 1.0 mg GA3 equivalents per liter. 相似文献
5.
Udo Helmchen Heide Fischbach Udo Schmidt 《Journal of molecular medicine (Berlin, Germany)》1971,49(23):1298-1300
Zusammenfassung Eine einmalige intraperitoneale Furosemid-Gabe von 50–200 mg/kg KG führt in der Rattenniere zu Epithelschäden im Bereich der pars recta des proximalen Tubulus. Diese tubulären Veränderungen treten nicht auf, wenn der Furosemid-induzierte Wasser- und Elektrolytverlust durch einen experimentell angelegten vesico-venösen Shunt verhindert wird. Die Tubuluszellschäden werden als Folge einer intracellulären Furosemid-Anreicherung bei vermindertem intratubulären Harnstrom angesehen.Mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
6.
Eash HJ Jones HM Hattler BG Federspiel WJ 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2004,50(5):491-497
Hollow fiber membranes (HFMs) used in artificial lungs (oxygenators) undergo plasma leakage (or wetting) in which blood plasma slowly fills the pores of the fiber wall, plasma leaks into gas pathways, and overall gas exchange decreases. To overcome this problem plasma resistant fibers are being developed that are skinned asymmetric or composite symmetric versions of microporous oxygenator fibers. This report evaluates several candidate plasma resistant HFMs in terms of their gas permeance and plasma resistance as measured in a surfactant wet out test. Five candidate fibers were compared with each other and with a control fiber. CO2 and O2 gas permeance (in ml/s/cm2/cm Hg) in the plasma resistant fibers ranged from 3.15E-04 to 1.71E-03 and 3.40E-04 to 1.08E-03, respectively, compared with 1.62E-02 and 1.77E-02 for the control fiber. Maximum dye bleed through for the plasma resistant fibers in the forced wet out test were significantly less than for the control fiber. CO2 gas permeance of a plasma resistant fiber imposes the greatest constraint upon artificial lung design for sufficient gas exchange. However, our results suggest sufficient plasma resistance can be achieved using special skinned and composite HFMs while maintaining an acceptable CO2 gas permeance for a broad range of artificial lung applications. 相似文献
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Observations were carried out from May 1977 to May 1980 on occurrence, fauna, and seasonal dynamics of Gasterophilus spp. in 2,539 horses for butchering from all districts of the German Democratic Republic and also in 79 horses after control against gasterophilosis. 99.98% of the 13,742 second and third instar larvae of horses for butchering were Gasterophilus intestinalis, only 0.02% Gasterophilus nasalis. Out of 7,765 larvae passed after control measures Gasterophilus intestinalis dominated with more than 96%. Only in four districts of the German Democratic Republic Gasterophilus nasalis was found. The mean extensive invasion from 1977 to 1980 was 8.7%, the mean intensive invasion 33.4 +/- 3.16 larvae/infected horse, the number of larvae ranging between 2 and 576 per horse. From 1977/78 to 1979/80 the intensive invasion increased from 25.8 +/- 2.74 to 58.6 +/- 3.49 larvae/infected horse. Peaks of extensive invasion appeared in April, May and October. From October to February the horses harboured both second and third instar larvae of Gasterophilus spp. The occurrence of gasterophilosis is concentrated in the northern parts of the German Democratic Republic. 相似文献
8.
Tissue cages for study of experimental streptococcal infection in rabbits. I. Production of erythrogenic toxins in vivo 总被引:2,自引:0,他引:2
Tissue cages implanted subcutaneously were used to infect rabbits with erythrogenic toxin (ET) producing streptococci. The in-vivo production of ET was followed during the infection by immunoprecipitation analyses of the tissue cage fluid (TCF). ET types A and C were mainly detected during the first week of infection, but, as late as 4 weeks after the inoculation, ET was occasionally found in TCF. The nonspecific mitogenic activity of ET on human lymphocytes was also used as a biological marker to recognize ET in TCF. Mitogenic activity was detected in 90% of samples during the first week. In order to characterize the mitogenic material released by growing streptococci, TCF was electrofocused in polyacrylamide gel. The eluates of sliced gels were checked for mitogenic activity and compared with a purified ET preparation containing ET types A and C. It could be verified that ET type A was produced under in-vivo conditions by strains NY-5 and SF130, while ET type C was produced by strain T18. Differences between production of toxins in vitro and in vivo might be of significance for the understanding of the pathogenetic mechanisms in streptococcal infection. 相似文献
9.
A microplate enzyme-linked immunosorbent assay was developed to detect chicken anti-rovirus antibodies. Studies of the parameters which affect the outcome of the assay with avian serum revealed two aspects for a successful assay. First, enzyme-antibody conjugates prepared by the periodate oxidation technique were found to have retained far more immunological activity than conjugates produced by a glutaraldehyde cross-linking. Second, the results indicated an unusually high affinity of chicken immunoglobulin for the microplate plastic which was mostly eliminated by a pretreatment technique with fixed fetal calf serum. The enzyme-linked immunosorbent assay compared favorably with the latex passive agglutination test, yielding a titration endpoint of 1:511,000, or approximately 1,300 times more sensitive than the latex passive agglutination assay. The assay proved not only to be sensitive to less than 1 ng of specific antibody, but also to have low to moderate variance and high reliability. 相似文献
10.
Van der Poel WH Van der Heide R Van Amerongen G Van Keulen LJ Wellenberg GJ Bourhy H Schaftenaar W Groen J Osterhaus AD 《Archives of virology》2000,145(9):1919-1931
Summary. In July 1997 a lyssavirus was isolated in Denmark from a colony of Egyptian flying foxes (Rousettus aegyptiacus) originating from a Dutch zoo. Sequencing of a 400 nucleotides coding region of the nucleoprotein and of a major part of
the G-protein ectodomain encoding region of the newly isolated virus, revealed a very high similarity with European Bat Lyssavirus
subtype 1a (EBL-1a). For characterisation of the recently isolated lyssavirus in frugivorous zoo bats, 16 frugivorous bats
(Rousettus aegyptiacus) of the same colony and 80 mice were experimentally infected with the Rousettus isolate or with a well defined EBL-1a strain
isolated from a Dutch insectivorous bat (Eptesicus serotinus). Inoculation viruses were titrated in mice to determine LD50‘s of both isolates. Clinical signs of inoculated bats were recorded during 6 weeks. After showing neurological signs or at
the end of the experimental infection all animals were euthanized. During the experimental infection sera and various tissues
of inoculated bats were collected. Immunoassays, mouse inoculation tests (MIT) and polymerase chain reaction (PCR) were employed
for detection of lyssavirus specific antibodies, antigen or RNA. Five bats inoculated with the Rousettus isolate and 2 bats
inoculated with the Eptesicus isolate showed neurological signs. The remaining 9 bats survived and cleared the virus; at least
under the detection limit of the used assays. Despite a much higher pathogenicity of the Rousettus isolate observed in mice,
LD25’s in bats were quite the same for the 2 isolates. The pathogenicity of both isolates suggested that like many other mammals,
Rousettus aegyptiacus bats could be victims of lyssavirus infection besides reservoir hosts of infectious EBL1a. There was no significant difference
in detecting the different lyssavirus isolates in Rousettus aegyptiacus bats. An employed immunoperoxidase staining (IP) method was very useful for sensitive detection and localization of lyssavirus
antigen in histologic preparates.
Received July 26, 1999/Accepted February 18, 2000 相似文献