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991.
The time course of biochemical and histological changes following carbon tetrachloride-induced liver damage in rats of both sexes 总被引:1,自引:0,他引:1
A detailed analysis is presented of the time changes in the development of liver damage 6, 12, 24, 48 and 72 hours after i.p. administration of carbon tetrachloride [CCl4] in a dose of 0.75 ml, i.e. 1 200 mg/kg body weight to rats of both sexes. The severity of liver damage was assessed from the histological and biochemical changes of AST, ALT, alkaline phosphatase and GMT serum activity. From our experiments it follows that in male rats the level of transaminases increases earlier than in female rats, as early as 6 h after the administration of CCl4, reaching a maximum 12 h later. These changes prevail for a longer time period, the level of transaminases remaining increased even 72 h after CCl4 administration. In female rats the biochemical changes occur later reaching the maximum elevation of AST and ALT 24 h after CCl4 administration. The values slowly return to normal after 48 h, and after 72 h the levels of transaminases are identical with the control group. The above given biochemical results are in good agreement with the histological findings demonstrating a higher regenerative activity in female rats. This finding was also proved by specific liver DNA activity assay. 相似文献
992.
Edda De Rossi Giovanna Riccardi Anna Maria Sanangelantoni Orio Ciferri 《FEMS microbiology letters》1985,30(1-2):239-244
Abstract A Spirulina platensis gene library has been constructed using cosmid vector pMMB34. The cosmid bank was controlled for its random gene distribution by colony hybridization. Genes were identified using either homologous or heterologous probes of genes involved in photosynthesis (large and small subunit of d -ribulose 1,5-bisphosphate carboxylase, 32 kDa thylakoid protein, α, β subunits of C-phycocyanin) and protein synthesis (elongation factors EF-Tu, EF-G). 相似文献
993.
Guatteria, Guatteriopsis, Guatteriella andHeteropetalum share the same conspicuous pollen type which is new for theSpermatophyta. It is zonoaperturate with a folded aperture region and an extremely reduced exine. First chromosome counts and karyotype analyses forGuatteriopsis (4 species investigated) andGuatteriella (1 species) are identical with those ofGuatteria (19 species seen): 2n = 28. The genome is characterized by diploidization and partly telocentric chromosomes. Sequentially Giemsa C- and fluorochrome banded chromosomes and interphase nuclei are described. The cuticular folding pattern is distinct forHeteropetalum only. Growth forms and ecology are reported for many species. The evolutionary pattern of theGuatteria group is discussed and compared with other genera and families. 相似文献
994.
Ján Michalko 《Folia Geobotanica》1985,20(3):313-317
Classification of euhemerobic calciphilous pine-communities should be based on studies carried out over an extensive area and for several seasons. The Malé Karpaty Mts. are situated near the northern boundary of the distribution ofPinus nigra and it is mecessary to find the planting time of allPinus nigra stands. The common use ofEllenberg’s “Zeigerwerte der Gefässpflanzen Mitteleuropas” for the ecological evaluation of plant communities in the Western Carpathians Mts. is criticised for several reasons. 相似文献
995.
Lidia Sautebin Hans Kindahl Maria Kumlin Elisabeth Granstrm 《Prostaglandins & other lipid mediators》1985,30(3):435-456
Conjugates of prostaglandins and thromboxanes with tritium labeled amino acids were prepared and employed as labeled ligands in porstaglandin and thromboxane radioimmunoassays. Assays for PGF2α, 15-keto-13, 14-dihydro-PGF2α, TXB2 and 15-keto-13, 14-dihydro-TXB2 were evaluated in comparative studies using either these heterologous ligands or the corresponding homologus tritiated eicosanoid as tracers. Binding properties for the respective antibodies were found to be similar using either tracer.Three biological studies were also conducted, viz. study of the release of TXB2 during collagen induced platelet aggregation, of 15-keto-13, 14-dihydro-TXB2 during guinea pig pulmonary anaphylaxis, and of PGF2α (measured as 15-keto-13, 14-dihydro-PGF2α in peripheral plasma) during bovine luteolysis. The analyses gave comparable results using either the heterologous or the homologous assay.Thus, this type of labeled prostanoid conjugates may serve as a convenient alternative to homologous tracers in radioimmunoassay. Heterologous tracers may even in certain cases provide the only simple solution to the problem of preparing a labeled ligand of high specific activity. 相似文献
996.
A method is proposed to analyse the dispersion profiles of species in classes of environmental variables, based on the decomposition of the expected frequencies in contingency tables with many interacting species. The method has been applied to data of dominant or very frequent graminoid species in grasslands of the Natisone Valley (Friuli, Italy). It allowed to make predictions by removing the random component of variation.Nomenclature follows: P. Zangheri (1976). Flora Italica, CEDAM, Padua.The authors were recipients of an Italian CNR grant (E. Feoli) and a Canadian NSERC grant (L. Orlóci) during tenure of this project. The results are in partial fulfillment of a commitment to the Centro Regionale per la Sperimentazione Agraria per il Friuli-Venezia Giulia. 相似文献
997.
Javier G. Fernández Velasco Norma L. Pucheu Oscar Romero Norma L. Kerber Raúl A. Fernández Augusto F. García 《Archives of microbiology》1985,143(2):192-195
The conditions under which an oscillatory behaviour is observed during net hydrolysis or synthesis of ATP in chromatophores of Rhodospirillum rubrum FR1 are described. In the case of ATPase the oscillations are observed at low temperature (ca. 11°C) in the dark after an initial transient behaviour. These oscillations are attenuated or disappear by the addition of an uncoupler.Oscillations are also observed during ATP synthesis. At 3°C the oscillations appear spontaneously if photophosphorylation is measured during a sufficiently long time. At 30°C the mere intercalation of a dark period also at 30°C is sufficient to trigger the oscillations in the following light period.Abbreviations Bchl
Bacteriochlorophyll
- FCCP
carbonyl cyanide p-trifluoromethoxyphenyl hydrazone
- PMS
phenazine methosulfate
- TMPD, N,N,N,N
tetramethyl-1,4-phenylenediamine
Dedicated to Prof. Dr. Gerhart Drews as a homage for his permanent example as hard worker and careful scientist and also for his remarkable human quality 相似文献
998.
Francisco Romero Francisco Javier Caballero Francisco Castillo José Manuel Roldán 《Archives of microbiology》1985,143(2):111-116
Anti-glutamine synthetase serum was raised in rabbits by injecting purified glutamine synthetase (GS) of the phototrophic bacterium Rhodopseudomonas capsulata E1F1. The antibodies were purified to monospecificity by immunoaffinity chromatography in GS-sepharose gel. These anti-GS antibodies were used to measure the antigen levels in crude extracts from bacteria, grown phototrophically with dinitrogen, nitrate, nitrite, ammonia, glutamate, glutamine or alanine as nitrogen sources. The amount of GS detected by rocket immunoelectrophoresis was proportional to Mn2+-dependent transferase activity measured in the crude extracts. Addition of GS inhibitor l-methionine-d,l-sulfoximine (MSX) to the actively growing cells promoted increased antigen levels, that were not found in the presence of glutamine or chloramphenicol. The ammonia-induced decrease in GS relative levels was reverted by MSX. GS levels remained constant when phototrophically growing cells were kept in the dark.Abbreviations GS
glutamine synthetase
- MOPS
2-(N-morpholine) propane sulfonate
- MSX
l-methionine-d,l-sulfoximine 相似文献
999.
Maria V. Croce Marcela Fejes Norma Riera D. A. Minoldo Amada Segal-Eiras 《Cancer immunology, immunotherapy : CII》1985,20(1):91-95
Summary A total of 122 sera from acute lymphoblastic leukemia (ALL) patients were analyzed for circulating immune complexes (CIC) by two methods: the 125I-C1q binding assay and the polyethylene glycol precipitation test (PEG). The results were correlated with induction, remission and relapse stages of the disease. Using the first method the levels of CIC in induction were 15.18±9.15, with 19/29 positive cases (65.50%), P<0.001 compared with controls. In the remission phase the levels were 9.02±5.62, 11/45 (24.49%) nonsignificant P value, and in relapse they were 16.14±11.17 28/48 (58.33%) P<0.001. The PEG precipitation test results were: 0.33±0.10, 8/22 (36.36%); 0.24±0.11, 10/48 (20.83%) and 0.28±0.10, 6/28 (21.42%), respectively. Thus the values of CIC as measured by PEG in the three clinical of phases ALL did not differ significantly from controls. This contrasts with results obtained by the radioiodinated C1q binding assay, where the incidence of positive values was significantly higher in induction and in relapse and lower in the remission phase. These observations were extended in sequential vertical studies performed in a group of patients. These results suggest that raised CIC detected by the 125I-C1q method may reflect a progressive state in ALL and that quantitation of these immune complexes may provide an adequate biochemical marker for prognosis. 相似文献
1000.
Formation of protoplasts and their reversion were followed in 7 strains of brevibacteria. The formation of protoplasts and
their reversion differed both between various species of brevibacteria and between various mutant strains of the same species. 相似文献