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1.
N-Methyl-D-Aspartate receptors in acquisition of the short-term memory in the honeybeeApis mellifera
N. G. Lopatina I. V. Ryzhova E. G. Chesnokova L. A. Dmitrieva 《Journal of Evolutionary Biochemistry and Physiology》2000,36(3):294-300
Role of NMDA receptors in the process of associative learning has been studied in the honeybeeApis mellifera L. in behavior experiments, using method of conditional reflexes. To determine pharmacological profile of NMDA receptors,
effects of Mg2+ ions, NMDA, glycine (Gly), antagonist of the glycine site 5,7-dichlorokynurenic acid (DCK), competitive antagonists of NMDA
receptors: D,L-2-aminophosphovalerate (APV), L-2-aminophosphobutyrate (APB), and D-glutamyl-aminomethylphosphonic acid (GAMP)
as well of antagonists of NMDA receptor ion channels MK-801 and ketamine (Ket) were studied on acquisition of alimentary conditional
reflex and its retention in memory. NMDA increased capacity for learning by stimulating shortterm memory. The NMDA receptor
co-agonist Gly activated this NMDA effect. DCK eliminated the NMDA and Gly stimulatoty effects. All tested antagonists at
millimolar concentrations inhibited associative function. The data obtained confirm our hypothesis about participation of
NMDA receptors in processes of formation of short-term memory in the honeybeeApis mellifera and suggest that functional characteristics of the NMDA receptors involved in the process of associative learning in the
honeybee resemble those in mammals. 相似文献
2.
Yu. N. Litvinov N. T. Erzhanov N. V. Lopatina T. Zh. Abylkhasanov 《Contemporary Problems of Ecology》2010,3(5):593-596
Small mammals were studied in the Kazakh Uplands in the spring and fall of 2008. The trapping studies revealed 10 species.
Abundances of the animals were low in the four main distinct characteristic biotopes of Bayanaul National Park, but those
of biotope dominants were high. In the Kazakh Uplands, rodents and insectivores are clearly restricted to certain biotopes.
Biodiversity indices for small mammal communities are low, indicating that the community structure is disturbed. 相似文献
3.
We have analyzed a total of 12 different global and local multiple
protein-sequence alignment methods. The purpose of this study is to
evaluate each method's ability to correctly identify the ordered series of
motifs found among all members of a given protein family. Four
phylogenetically distributed sets of sequences from the hemoglobin, kinase,
aspartic acid protease, and ribonuclease H protein families were used to
test the methods. The performance of all 12 methods was affected by (1) the
number of sequences in the test sets, (2) the degree of similarity among
the sequences, and (3) the number of indels required to produce a multiple
alignment. Global methods generally performed better than local methods in
the detection of motif patterns.
相似文献
4.
Pukhalsky AL Bliacher MS Danilina AV Kalashnikova EA Lopatina TK Fedorova IM 《Mediators of inflammation》1996,5(6):429-433
The effect of vaccination with diphtheria toxoid (AD-M) on TNF and IL-6 production has been studied in humans. In the present study it was demonstrated that immunization with AD-M resulted in changes of in vitro TNF and IL-6 production by peripheral blood mononuclear cells. TNF release was suppressed but IL-6 production was stimulated. On the other hand, serum levels of TNF were markedly increased over a period of 3 weeks. It was also demonstrated that the postvaccinal cytokine production disturbances may be corrected by pretreatment with a new synthetic hexapeptid (Imunofan((R))). It is possible that the imunofan treatment could prevent some postvaccinal complications. 相似文献
5.
N V Shiriaeva A I Va?do N G Lopatina D A Kulagin T S Glushchenko N P Taranova 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1992,42(1):137-143
The influence was studied of 15-days stressing on the appearance of stable neurosis-like state of rats lines, selected by the excitability of the nervous system. Unconditioned and conditioned components of behaviour were tested: pain sensitivity, behaviour in the open field, level of "anxiety", passive and active defensive avoidance. Differential reactivity was shown of the rats lines to prolonged stressing, depending on the genetically determined level of the nervous system functional state. Interlinear differences in dynamics of the development of neurosis-like state were established. 相似文献
6.
Determination of the recognition sites of cytosine DNA-methylases from Escherichia coli SK. 下载免费PDF全文
Two different cytosine DNA-methylases, NI and GII, are present in Escherichia coli SK. The GII methylase recognizes the five-member symmetric sequence: 5'...NpCpCpApGpGpN...3'. This sequence is identical with the recognition site of the hsp II type determined by RII plasmid but, in contrast to RII methylase, the GII enzyme methylates cytosine located on the 5' side of the site. By analogy with the isoshizomery of the restricting endonucleases, RII and GII DNA methylaeses may be called isomethymers which recognize the same site but methylate different bases. Since the phage of the SK and hsp II phenotypes is effectively restricted in respective cells it may be assumed that the isomethymeric modification does not provide any protection against the corresponding restrictases. NI methylase recognizes the five-member symmetric site which represents an inverted sequence of the GII site: 5'...NpGpGpApCpCpN...3'. In this case cytosine at the 3'-end of the recognition site is methylated. 相似文献
7.
I. I. Nikolskaya N. G. Lopatina N. M. Chaplygina S. S. Debov 《Molecular and cellular biochemistry》1976,13(2):79-87
E. coli SK has its own enzyme system providing DNA host specificity which differs from the known types of specificity inE. coli K12 andE. coli B. Modification and restriction are observed when the PBVI or PBV3 phages are transferred fromE. coli SK toE. coli B or K12 (and back).A methylase has been isolated fromE. coli SK cells and partly purified. This methylase catalyzesin vitro transfer of the labelled methyl groups from S-adenosylmethionine (SAM) to DNA of both phage and tissue origin which gives rise to 5-methylcytosine (5MC) and 6-methylaminopurine (6MAP). The methylase preparations isolated from the cells at the stationary growth have proved to be 1.5–1.7 times as active as the enzyme from the cells at the logarithmic growth stage. The extract ofE. coli SK cells infected with the phage SD cannot methylate DNAin vitro. This fact is due tode novo synthesis of the enzyme which disintegrates SAM down to 5-methylthioadenosine (5MTA) and homoserine (HS). This enzyme is not found in the cells infected with the SD phage in the presence of chloroamphenicole. The activity of the enzyme which disintegrates SAM is the highest between the 4th and the 5th minutes of infection. Thus it may be assumed that this enzyme, most probably, is an early virus specific protein and preventsin vivo methylation of the phage DNA. 相似文献
8.
9.
Kazakova O. B. Smirnova I. E. Medvedeva N. I. Lopatina T. V. Chudov I. V. Sharipov A. R. Ziganshin A. S. Thao Tran Thi Phuong 《Russian Journal of Bioorganic Chemistry》2019,45(6):558-565
Russian Journal of Bioorganic Chemistry - The regioselective synthesis of betulin 3,28-bis- and 28-monoacylates (nicotinate and isonicotinates) as well as of 3β-hemisuccinyl dipterocarpol was... 相似文献
10.
The African Black Oystercatcher Haematopus moquini is a charismatic, southern African near-endemic, wader species, that is often seen as a flagship species for coastal bird conservation, as it was recently down-listed regionally to Least Concern on the IUCN Red List of Threatened Species. To celebrate this rare conservation success story, BirdLife South Africa named it the 2018 Bird of the Year and ran a year-long programme in collaboration with the Nature’s Valley Trust highlighting aspects of the species’ biology, current threats, and conservation success. We used data collected by the Southern African Bird Atlas Project (SABAP1 and SABAP2) to examine changes in the species’ range and relative abundance, both in the records between the two projects, as well as trends within the SABAP2 sampling period (2008–2017). This case study enabled us to assess whether such metrics can accurately reflect abundance and distributional changes in a species. We found increases in the reported range and the reporting rates between the two Atlas projects, and that the SABAP2 reporting rate was stable. Regionally, across four coastal categories, the reporting rate was lowest in KwaZulu-Natal, though this region also showed an increase in the probability of reporting during the SABAP2 period. While corroborating the recent change in the species’ conservation status, we also provide good evidence that the long-term SABAP data can be used successfully to assess population trends and range changes over time. 相似文献