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101.
N Iu Belenkov V V Gracheva I I Stepanov 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1985,35(3):473-479
Probability analysis was carried out of the appearance of single elements of rats behaviour in the process of extinction of a conditioned alimentary motor reflex. The dynamics of effector behavioural components at a sudden cessation of reinforcement (usual schedule of extinction) was compared with cessation of reinforcement signalled by a previously differentiated signal and with reinforcement cessation preceded by a stimulus initially unknown to the animal. If the reinforcement cessation is signalled by a previously differentiated (negative) stimulus, in response to its action the animals "loose the aim", what is revealed in a rapid complete reduction of all elements of the goal-directed alimentary behaviour. Obviously differentiation signal actualises the memory trace of "nonreinforcement" which was formed in the previous negative experience of the animal; this is revealed in accelerated inhibition of the alimentary motor reflex under extinction. 相似文献
102.
V V Kupriyanov V L Lakomkin O V Korchazhkina V A Stepanov V I Steinschneider AYaKapelko 《Biochimica et biophysica acta》1991,1058(3):386-399
In order to investigate the potential role of cytosolic phosphates ([ATP], [ADP] and [Pi]) in the integration of mitochondrial respiration and mechanical function in the perfused heart, inhibition of the substrate end of the respiratory chain by amytal has been employed. A stepwise increase in amytal concentration (from 0.2 to 1.2 mM) resulted in the progressive abolition of the cardiac oxygen consumption, rate (VO2) in hearts oxidizing pyruvate (5 mM). The inhibition curve for VO2 was S-shaped, with K0.5 = 1.1 mM, and independent of the initial VO2 values varied by coronary flow and isoproterenol (Iso) addition. ADP-stimulated respiration of isolated mitochondria (malate + pyruvate) was twice as sensitive to amytal inhibition, whereas state 2 respiration (before ADP addition) had the same sensitivity as cardiac VO2. Decrease in VO2 was followed by a decline in phosphocreatine (PCr) content and augmentation of Pi at nearly constant ATP level and intracellular pH as assessed by the 31P-NMR method. These changes were associated with an elevation of cytosolic free [ADP] and a reduction of the [ATP]/[ADP] ratio and ATP affinity calculated from creatine kinase equilibrium. Concomitantly, pressure-rate product (PRP), maximal rates of contraction and relaxation fell down and the end diastolic pressure (EDP) rose at all initial loads. Amytal-inhibited hearts retained the capability to respond to Iso stimulation (0.1 microM, about 50% enhancement of PRP) even at 1 mM amytal, but their response to elevation of coronary flow was greatly diminished. Alterations in the PRP value induced by the inhibitor at a fixed coronary flow correlated negatively with cytosolic [ADP] and [Pi], and positively with [ATP]/[ADP] and A(ATP). In contrast, EDP correlated with all these parameters in the opposite manner. However, when PRP was varied by coronary flow in the absence of the inhibitor or at its fixed concentrations, such correlations were absent. These data imply that cytosolic phosphates can serve as a feedback between energy production and utilization when the control point(s) is (are) at the mitochondria. In contrast, other regulatory mechanisms should be involved when control is distributed among different steps located both in energy producing and utilizing systems. 相似文献
103.
As demonstrates the investigation of 100 preparations, the main vascular-nervous "hilus" of the muscle is situated on the superior third of its lateral part. They contain the transversal branch of the medial artery, circumflexing the femoral bone with the accompanying vein, having the same name, and the anterior branch of the obturative nerve (92 preparations), or muscle branch of the femoral nerve (8 preparations). The muscle has a well developed network of intrasystemic and intersystemic anastomoses. Beginning from the first period of childhood, for sphincter plasticity either the whole muscle, or a graft, cut out from its lateral part, can be used. 相似文献
104.
105.
B B Fuchs N F Avrova N A Starosvetskaya M N Boltovskaya E I Zaraisky O B Karpova E V Reznikova L N Soldatova A A Stepanov 《Biotechnology and applied biochemistry》1988,10(3):273-286
Immunization of mice with a pure preparation of the ganglioside adsorbed on Salmonella typhimurium and hybridization of splenocytes with myeloma P3-X63-Ag 8.653 have resulted in hybridomas producing monoclonal antibodies against ganglioside Fuc GM1, a marker of human small cell lung carcinoma. Characterization of four hybridomal clones and data on the antigenic specificity of the monoclonal antibodies are given. All four monoclonal antibodies reacted only with Fuc GM1 in an enzyme-linked immunosorbent assay. In radioimmunodetection of the antigen on thin-layer plates, two of the four monoclonal antibodies gave cross-reactions with Fuc GD1b. The obtained monoclonal antibodies have revealed the presence of Fuc GM1 in all seven cases of small cell lung carcinoma we have studied and the absence of Fuc GM1 in the normal human lung tissue and in lung adenocarcinomas. 相似文献
106.
I A Surova V V Ianonis L P Revina E D Levin V M Stepanov 《Bioorganicheskaia khimiia》1988,14(6):783-789
Method of isolation of intracellular serine protease was modified. Gramicidin S-sepharose CL-4B with a higher content of the ligand, synthesized through a modified procedure, was used as an affinity sorbent which simplified the purification and led to the pure enzyme with high specific activity and 90% yield. Trypsin hydrolyzate of the protease was separated by ion-exchange chromatography on a sulphocationite resin followed by paper chromatography and paper electrophoresis to yield twenty-five individual peptides. Their complete or partial sequences, corresponding in total to 146 amino acid residues, were determined by the manual Edman procedure. 相似文献
107.
Cyanide-ferrihemoglobin (myoglobin) interaction was studied by freeze-quenching technique and low-temperature ESR at various pH values. New ESR signals of these low-spin cyanide-protein complexes were recorded. These signals were interpreted as indication of the appearance of conformationally non-equilibrium states of these complexes. The relaxation to the equilibrium states of corresponding proteins takes about hundred milliseconds. 相似文献
108.
Anatomical and echographic data have been compared in 35 mature human kidneys. Ultrasound anatomy of the kidney has been verified. It has been stated that the central part of the renal echogram is occupied by the zone of intensive echosignals, that corresponds not to the calyceal complex, as it had been considered previously, but to the renal sinus. The renal sinus filled with fatty tissue and small arterial and venous vessels, their diameter is below the resolving power of the ultrasound device, is visualized as fused intensive echosignals of an elongated form, when the renal scanning is longitudinal, and as oval or round -- when the scanning is transversal. The calyceal-pelvic complex, filled with liquor, is presented as an anechogenic branching structure, situating within the zone of an increased echogeneity. The echographic picture of the calyceal-pelvic complex is always fragmentary: as small anechogenic areas in the hyperechogenic zone mentioned (the small pelvic calyces), or an excentrically situated anechogenic zone near the hilus renalis (the renal pelvis). In order to make the echographic investigations more accurate, it is necessary to follow certain methodical requirements, anatomical comparisons including. 相似文献
109.
G. G. Chestukhina S. A. Tyurin L. I. Kostina A. L. Osterman I. A. Zalunin O. A. Khodova V. M. Stepanov 《The protein journal》1990,9(4):501-507
N-Terminal domain (65 kD) of δ-endotoxin produced byBacillus thuringiensis ssp.alesti, as shown by limited proteolysis, consists of two subdomains of molecular mass 30 and 33 kD that correspond, respectively, to conservative and variable regions of the δ-endotoxin primary structure. Furthermore, proteolysis of these subdomains leads to their conversion into at least two fragments of molecular mass 10 kD stable to proteinase action. Such a pattern of molecular organization appears to be common for several structurally related δ-endotoxins that belong to thekurstaki group. Entomicidal protein produced by ssp.israelensis (70 kD), which differs strongly fromalesti and otherkurstaki group δ-endotoxins, retains a similar type of molecular organization and consists of two subdomains with molecular mass of ~35 kD. Apparently, the characteristic pattern of the δ-endotoxins' molecular structure reflects separation of functions (e.g., host recognition and toxicityper se) between domains and subdomains of these proteins. 相似文献
110.
Genetic relationships among eight Siberian and Central Asian ethnic groups were examined using autosomal microsatellite loci. Genetic similarity of Buryats and Evenks, as well as close relationships between Tuvinians and Kyrgyzes, most likely resulting from the Altai-Slavic co-ancestry of their gene pools, was demonstrated. Studies of gene flow in these populations demonstrated that, in general, Turkic ethnic groups of Southern Siberia (Altaians and Tuvinians) were the recipients of more intense gene flow compared to Eastern Siberian populations belonging to Altaic family. The local Buryat populations displayed substantial differences in the direction and the level of deviation of the observed gene diversity from the expected one, which was probably caused by the differences in the degree of isolation and/or in effective population sizes. 相似文献