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11.
A mathematical model is examined of interaction between cones and horizontal L-type cells (HC) in the carp retina using data from intracellular recording of HC spectral response. This model, describing the operation of ionic channels at the membrane of cones and HC, is based on a numerical analog solution to Hodgkin-Huxley differential equations [11] and enables predictions of spectral response levels in HC to be made as a function of time.M. L. Lomonosov State University, Moscow. Translated from Neirofiziologiya, Vol. 21, No. 4, pp. 461–466, July–August, 1989. 相似文献
12.
V G Savchenko V G Isaev E M Abakumov N D Khoroshko A G Turkina A N Sokolov M M Viadro S M Navashin 《Antibiotiki i khimioterapii͡a》1992,37(7):47-49
The clinical efficacy of aclarubicin, an anthracycline antibiotic, was studied in 48 patients with leukemia. The antibiotic was used in the following combinations with cytarabine: "7 + 7", "5 + 5" and "7 & 3". A complete remission was stated in 14 (42.4 per cent) out of 33 patients with acute nonlymphoid leukemia, 6 (43 per cent) out of the 14 patients having relapses. The combined therapy was effective in 4 out of 5 pre-resistant patients. The "7 + 3" scheme was the most beneficial. The most common adverse reactions were nausea and vomiting. 相似文献
13.
N N Sokolov M A El'darov N V Anike?cheva I V Karpychev O T Samko A B Fitsner A A Kalugin E B Khoroshutina K G Skriabin 《Bioorganicheskaia khimiia》1991,17(9):1188-1192
A new site-specific endonuclease was detected in toluene lysates of Bacillus coagulans AUCM B-732 and designated as BcoAI. The enzyme was purified by fractionation of the cell-free extract in the two-phase PEG/dextran system followed by chromatography on DEAE-sepharose and phosphocellulose and shown to be free of nonspecific nucleases and phosphatases. BcoAI has three cleavage sites on lambda DNA, but does not cleave SV40, pBR322 and pUC19 DNA. BcoAI recognizes the sequence 5' CAC decreases GTG 3' on double-stranded DNA and cleaves it as indicated by the arrow to yield blunt-ended DNA fragments. Thus, BcoAI is a true isoschizomer of PmaCI from Pseudomonas maltophila C. 相似文献
14.
15.
N N Sokolov Z P Manialene V V Butkus A B Fitsner E B Khoroshutina A A Kalugin A A Ianula?tis 《Bioorganicheskaia khimiia》1990,16(8):1040-1044
New site-specific endonucleases LplI and AagI have been isolated from the Lactobacillus plantarum and Achromobacter agile cells, respectively. The enzymes' purification stages included treatment of cell-free extracts with polyethylenimine, fractionation in two-phase system by Albertsson's method, chromatography on blue Sepharose and DEAE-cellulose. The results of cleavage of a 5'-32P-labelled oligodeoxynucleotide duplex by restriction endonucleases LplI and AagI indicate that these enzymes recognize and cut the sequence AT decreases CGAT, being therefore true isoschizomers of the ClaI restriction endonuclease from Caryophanon latum. The L. plantarum strain has 400 fold endonuclease productivity as compared with the ClaI producent and is perspective for preparative isolation of LplI. 相似文献
16.
34Fusarium graminearum Schw isolates produced 4-deoxynivalenol to form significant amounts of 4, 7 — dideoxynivalenol and lesser amounts of 4 — deoxynivalenol monoacetates on grain substratesin vitro. This is the first report on the capability a large group of naturally occurring isolates to produce 4,7-dideoxynivalenol. The average levels of 4,7-dideoxynivalenol on rice, corn, barley, and wheat as a substrate were respectively 26.8, 14.0, 12.8, and 10.5% of the level of 4-deoxynivalenol. 4, 7 — dideoxynivalenol was present in all examined naturally contaminated wheat kernel samples at levels of 1.7 to 7.9% of the level of 4-deoxynivalenol. These findings suggest that more attention should be given to the occurrence of 4,7-dideoxynivalenol in cereals. 相似文献
17.
The expression of gene(s) governing apomictic reproduction inTripsacum provides the best foundation for comparing the effectiveness of apomictic reproduction in a series of maize-Tripsacum hybrids. Several 38-chromosome, apomictic maize-Tripsacum hybrids are available which possess the gene(s) conferring apomictic reproduction fromTripsacum. Without a base line for comparison, studies directed towards discerning the successful transfer or effectiveness of gene expression in a maize background are hampered. The objectives of this study are to compare the reproductive features found in apomicticTripsacum with those in apomictic maize-Tripsacum hybrids. In addition, this study determined the feasibility of utilizing these maize-Tripsacum hybrid materials to continue an attempt to transfer the genes into a pure maize background. The frequency and occurrence of five unique reproductive features found in apomictic accessions ofTripsacum dactyloides were compared to the reproductive behaviours exhibited in the maize-Tripsacum hybrids. Results indicate the genes controlling apomixis in tetraploidTripsacum are fully functional in maize-Tripsacum hybrids with diploid and triploid maize constitutions. The ability of theTripsacum apomictic genes to retain full expression provides evidence to continue their transfer to a diploid or tetraploid maize background.The use of company names in this publication does not imply endorsement by the USDA-ARS, or the product names or criticism of similar ones not mentioned. All programs and services of the U.S. Department of Agriculture are offered on a nondiscriminatory basis without regard to race, color, national origin, religion, sex, age, marital status, or handicap. 相似文献
18.
19.
Minimal photosynthetic catalytic F1() core complexes, containing equimolar ratios of the and subunits, were isolated from membrane-bound spinach chloroplast CF1 and Rhodospirillum rubrum chromatophore RrF1. A CF1-33 hexamer and RrF1-11 dimer, which were purified from the respective F1() complexes, exhibit lower rates and different properties from their parent F1-ATPases. Most interesting is their complete resistance to inhibition by the general F1 inhibitor azide and the specific CF1 inhibitor tentoxin. These inhibitors were earlier reported to inhibit multisite, but not unisite, catalysis in all sensitive F1-ATPases and were therefore suggested to block catalytic site cooperativity. The absence of this typical property of all F1-ATPases in the 11 dimer is consistant with the view that the dimer contains only a single catalytic site. The 33 hexamer contains however all F1 catalytic sites. Therefore the observation that CF1-33 can bind tentoxin and is stimulated by it suggests that the F1 subunit, which is required for obtaining inhibition by tentoxin as well as azide, plays an important role in the cooperative interactions between the F1-catalytic sites.Abbreviations CF0F1
chloroplast F0F1
- CF1
chloroplast F1
- CF1
chloroplast F1 subunit
- CF1
chloroplast F1 subunit
- CF1()
a complex containing equal amounts of the CF1 and subunits
- MF1
mitochondrial F1
- RrF0F1
Rhodospirillum rubrum F0F1
- RrF1
R. rubrum F1
- RrF1
R. rubrum F1 subunit
- RrF1
R. rubrum F1 subunit
- RrF1()
a complex containing equal amounts of the RrF1 and subunits
- Rubisco
Ribulose-1,5-bisphosphate carboxylase
- TF1
thermophilic bacterium PS3 F1 相似文献
20.
Hummel Herman Bogaards Roelof Bek Tatiana Polishchuk Lennard Amiard-Triquet Claude Bachelet Guy Desprez Michel Strelkov Peter Sukhotin Alex Naumov Andrei Dahle Salve Denisenko Stanislav Gantsevich Michael Sokolov Kirill Wolf Lein de 《Hydrobiologia》1997,355(1-3):127-138
The stress sensitivity, determined in copper exposureexperiments and in survival in air tests, and thegenetic structure, measured by means of isoenzymeelectrophoresis, were assessed in populations of theBaltic clam Macoma balthica (L.) from itssouthern to its northern distribution limit, in orderto test the hypotheses that near the distributionlimit the clams would be more stress sensitive andwould have a lower genetic variability. Thepopulations in west and north Europe show a stronggenetic resemblance. The populations in the sub-ArcticWhite Sea are genetically slightly different, and showa low stress sensitivity. The populations in theArctic Pechora Sea are genetically very distant fromthe other populations, and show the lowest stresssensitivity. Near the southern distribution limit, inagreement with the hypotheses, genetic variability islow and stress sensitivity high. On the other hand, incontrast to expectation, near the northerndistribution limit, in the populations of the PechoraSea, the genetic variability was higher, thus notreduced, and the stress sensitivity was low comparedto all other populations. Yet, it remains a questionif such is due to gradual physiologicalacclimatization (and ongoing differential selection)or to genetic adaptation. 相似文献