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Continuous ambulatory peritoneal dialysis (CAPD) lavage can be interpreted as an artificial short-term ascites. The cellular content of 362 CAPD specimens from 32 patients was investigated. Irregular inflammatory reactions were seen in 85.3% of the specimens and eosinophilia in 27.6%. Mesothelial aggregates of great variability were registered in 59.4% of the specimens and mainly atypical mitoses in 7.5%. The cytologic changes seen in those patients from whom lavage fluids were examined over 10 to 12 months did not correlate with the changes in blood chemistry (BUN and creatinine) in those cases. 相似文献
13.
Creatine Transport in Cultured Cells of Rat and Mouse Brain 总被引:7,自引:3,他引:4
Astroglia-rich cultures derived from brains of newborn rats or mice use a transport system for the uptake of creatine. The uptake system is saturable, Na+-dependent, and highly specific for creatine and Na+. Kinetic studies on rat cells revealed a Km value for creatine of 45 microM, a Vmax of 17 nmol x h-1 x (mg of protein)-1, and a Km value of 55 mM for Na+. The carrier is competitively inhibited by guanidinopropionate (Ki = 15 microM). No such transport system was found in neuron-rich primary cultures from embryonic rat brain. It is hypothesized that creatine transport is an astroglial rather than a neuronal function. 相似文献
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Molecular evaluation of an Alu repeat including a polymorphic variable poly(dA) (AluVpA) in the vitamin D binding protein (DBP) gene 总被引:1,自引:0,他引:1
We investigated an Alu element at the end of intron 8 of the human vitamin D-binding protein (hDBP, group-specific component, GC) gene that shows a polymorphic poly(A) tail due to a variable number of tandem repeats (AluVpA) forming the 3 end of this member of the most abundant class of short interspersed repeated DNA element (SINES). The Alu element sequence in intron 8 of the GC gene was identical in all three common GC alleles (GC*1F, GC*1S, and GC*2) and could be classified as an Alu-Sa or Alu class-II sequence. The polymerase chain reaction was used to amplify selectively a fragment of about 200 bp containing the identified (TAAA)n repeat from genomic DNA of 188 unrelated human subjects. The size of the amplified products was determined by polyacrylamide gel electrophoresis. Four alleles (named GC-18*6, GC-I8*8, GC-I8*10, and GC-18*11) were found that differed in size by multiples of four nucleotides. The allele frequencies ranged from 0.0053 to 0.8511 and the observed heterozygosity was 26%. The stable inheritance of this polymorphic patterned poly(A) sequence was confirmed by a segregation study of a highly informative family with 19 members. Statistically significant linkage disequilibrium between the AluVpA and the GC isoelectric focusing (IEF) phenotypes was found in a sample of 188 unrelated individuals and delta values were calculated from the observed haplotype distribution. 相似文献
17.
Life cycle of the microbivorous Antarctic Dry Valley nematode Scottnema lindsayae (Timm 1971) 总被引:4,自引:2,他引:2
The life cycle of the Antarctic Dry Valley soil nematode, Scottnema lindsayae (Timm 1971) was studied in laboratory culture at two temperatures, 10°C and 15°C. Soil yeast and bacteria isolated with the nematodes were used as the food source. The species reproduced sexually. The higher temperature had a negative effect on the life cycle. The number of eggs per female and the number of juveniles developing per female were greater at 10°C than at 15°C. Juveniles developed faster at 10°C and four juvenile stages were observed outside of the egg at both temperatures. The unusually long life cycle (218 d at 10°C) suggests that more than one austral summer may be required for successful completion. An increase in Dry Valley soil temperatures associated with potential global environmental change may have detrimental effects on soil nematodes. 相似文献
18.
Summary Cats were treated with high doses of chloroquine for one year during which the ocular fundus was periodically examined. After completion of the treatment, the tapetal cells were investigated by light and electron microscopy. Prolonged treatment with the retinotoxic drug chloroquine reduced the light reflection of the fundus, and examination by light and electron microscopy revealed a destruction of the rod-like structures in the cytoplasm of the tapetal cells. 相似文献
19.
Genetic variation of a codominantly inherited pancreas protease, designated CTRA-1, was discovered in the house mouse by isoelectric focusing in polyacrylamide gels. Phenotype CTRA-1A was found in MOLH/Fre and in the majority of common laboratory mouse strains. Phenotype CTRA-1B was found in PWD/Ph. It was characterized by the absence of a corresponding protease band. A third phenotype, CTRA-1C, was observed in IS/Cam and a fourth phenotype, CTRA-1D, was detected in SEG/1. CTRA-1 was found only in the pancreas and may represent the A form of chymotrypsin. The enzyme was shown to be controlled by the presumed structural locus Ctra-1 located on chromosome 8. From two backcross series, including a total of 274 animals, the gene order (Es-1, Es-9)-3.9 +/- 1.7%-Got-2-3.9 +/- 1.7%-(Es-2, Es-7, Es-23)-0.7 +/- 0.5%- Ctra-1-6.3 +/- 2.2%-Prt-2 was established. 相似文献
20.
Andreas J. Helbig 《Journal of Ornithology》1990,131(1):63-71
Zusammenfassung Die Analyse von Sequenzunterschieden in mitochondrieller und genomischer DNA von Vögeln mittels Restriktionsenzymen eröffnet völlig neue Perspektiven für systematische, populationsgenetische und verhaltensökologische Forschung. Diese Methode ist der elektrophoretischen Untersuchung von Isoenzymen und der DNA-DNA-Hybridisierung vielfach überlegen. Das Prinzip, der technische Ablauf und die theoretischen Vorteile werden erläutert. Einige bisherige Untersuchungen dienen als Beispiele für vielversprechende Anwendungsmöglichkeiten in der Ornithologie. Die Einrichtung eines Schwerpunktlabors für solche Arbeiten wird vorgeschlagen, um technische und personelle Ausstattung optimal nutzen zu können.
Restriction enzyme analysis of DNA: principle and possible applications in ornithology
Summary The analysis of restriction fragment length polymorphisms in mitochondrial and genomic DNA of birds opens up a large new field of research for ornithologists. The method is in most contexts superior to electrophoretic analysis of allozymes and an important complement to DNA-DNA hybridization. Its principle, the technical procedures and theoretical advantages are briefly explained. Some recent studies are reviewed and potential applications outlined. Ornithological institutions in Germany should set up a central laboratory for such research to use personnel and technical equipment most efficiently.相似文献