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1.
2.
Using fluorimetric and polarographic determination of cell respiration, metabolic reactions of the carotid body of rats to adequate stimulation have been revealed. Functional relationships of the dose--effect type, which were found for these reactions, may be approximated by equations which are similar to those describing the unconditioned reflexes from the carotid chemoreceptors. However, reactions of the metabolics systems of the carotid body account for the perception of not all chemical stimuli, but only of acids and some alkaloids. These data reveal the heteregeneity of the carotid chemosensory system not only in the amphibians (which was known earlier), but in mammals as well. 相似文献
3.
T N Kuchma N D Konstantinova I S Samo?lenko 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1990,(9):20-23
The comparative study of the action of microwave radiation and hydrogen peroxide, as well as their combined action, on the viability and ultrastructure of P. aeruginosa cells has been made. The combined use of microwave radiation and hydrogen peroxide has been shown to decrease the viability of P. aeruginosa 1.5-2 times in comparison with the isolated action of each factor. The electron microscopic study of the ultrastructure of cells have shown the deterioration of the surface structures, nuclear and ribosomal apparatus of the cells under the isolated action of each of the above-mentioned factors or under their combined action. The morphological picture of these changes has proved to be different. The maximum changes in the ultrastructure of P. aeruginosa cells have been registered after the combined action of these bactericidal factors. 相似文献
4.
The advantage of using terrestrial isopods in toxicity studies is that a battery of parameters can be tested at different levels of biological complexity. Feeding parameters for example link organism level response to potential ecological consequences but a problem with using feeding parameters in toxicity tests with terrestrial isopods is their high variability. The aim of our study was to set benchmark values for feeding parameters for isopod Porcellio
scaber (Isopoda, Crustacea) in laboratory-controlled experiments. In the work presented here, the daily feeding rate of the central 50% of the control population of Porcellio
scaber and a correlation between feeding rate and isopod weight were set. Values outside these ranges need additional evaluation to increase the relevance of test outcomes. We suggest using benchmark values for feeding parameters as well as the coefficient of variation (a) to identify animals with altered feeding parameters with respect to controls, and (b) to assess the data quality in each experiment. 相似文献
5.
V N Obolenski? L S Aronov G V Rodoman A V Novikov L N Samo?lova V R Ga?tukaev 《Antibiotiki i khimioterapii͡a》2004,49(10):13-19
The clinical and economic efficacies of antibiotic prophylaxis in the surgical unit of the Hospital were confirmed by the results of the analysis of 1313 case records of the patients operated during a year for acute appendicitis and acute cholecystitis. At the same time it was shown advisable to use antibiotic therapy in the patients with various pathological processes. The dynamics of the microbial dissemination in the surgical unit and some other units of the Hospital, as well as the dynamics of antibiotic resistance of the microflora, its interrelation with the volume of the antibacterials used and their rotation are described. 相似文献
6.
Interactions between intrinsic regulation and neural modulation of acetylcholinesterase in fast and slow skeletal muscles 总被引:2,自引:0,他引:2
Janez Sketelj Neva Črne-Finderle Samo Ribarič Miro Brzin 《Cellular and molecular neurobiology》1991,11(1):35-54
1. Initiation of subsynaptic sarcolemmal specialization and expression of different molecular forms of AChE were studied in fast extensor digitorum longus (EDL) and slow soleus (SOL) muscle of the rat under different experimental conditions in order to understand better the interplay of neural influences with intrinsic regulatory mechanisms of muscle cells. 2. Former junctional sarcolemma still accumulated AChE and continued to differentiate morphologically for at least 3 weeks after early postnatal denervation of EDL and SOL muscles. In noninnervated regenerating muscles, postsynaptic-like sarcolemmal specializations with AChE appeared (a) in the former junctional region, possibly induced by a substance in the former junctional basal lamina, and (b) in circumscribed areas along the whole length of myotubes. Therefore, the muscle cells seem to be able to produce a postsynaptic organization guiding substance, located in the basal lamina. The nerve may enhance the production or accumulation of this substance at the site of the future motor end plate. 3. Significant differences in the patterns of AChE molecular forms in EDL and SOL muscles arise between day 4 and day 10 after birth. The developmental process of downregulation of the asymmetric AChE forms, eliminating them extrajunctionally in the EDL, is less efficient in the SOL. The presence of these AChE forms in the extrajunctional regions of the SOL correlates with the ability to accumulate AChE in myotendinous junctions. The typical distribution of the asymmetric AChE forms in the EDL and SOL is maintained for at least 3 weeks after muscle denervation. 4. Different patterns of AChE molecular forms were observed in noninnervated EDL and SOL muscles regenerating in situ. In innervated regenerates, patterns of AChE molecular forms typical for mature muscles were instituted during the first week after reinnervation. 5. These results are consistent with the hypothesis that intrinsic differences between slow and fast muscle fibers, concerning the response of their AChE regulating mechanism to neural influences, may contribute to different AChE expression in fast and slow muscles, in addition to the influence of different stimulation patterns. 相似文献
7.
Kulikov AV Bogatyrenko VR Likhtenshteĭn GI Allakhverdiev SI Klimov VV Shuvalov VA Krasnovskiĭ AA 《Biofizika》1983,28(3):357-362
The influence of Mn on saturation curves of ESR spectra of Ph(-) and P(+)(680) at 1-200K in samples with different content of Mn has been studied. An analysis of these data and those on photoinduced changes of fluorescence yield of chlorophyll leads to the conclusion that the Mn-containing centre in Photosystem 2 is a cluster of 4 Mn atoms, two of which can be replaced by Mg(2+) or any other divalent metal. The distances between Mn Na Ph as well as between Mn and P(680) have been estimated. 相似文献
8.
Rodriguez Maria E. Hozbor Daniela F. Samo Analia L. Ertola Rodolfo Yantorno Osvaldo M. 《Journal of industrial microbiology & biotechnology》1994,13(5):273-278
Summary The kinetics ofBordetella pertussis growth was studied in a glutamate-limited continuous culture. Growth kinetics corresponded to Monod's model. The saturation constant and maximum specific growth rate were estimated as well as the energetic parameters, theoretical yield of cells and maintenance coefficient. Release of pertussis toxin (PT) and lipopolysaccharide (LPS) were growth-associated. In addition, they showed a linear relationship between them. Growth rate affected neither outer membrane proteins nor the cell-bound LPS pattern.Nomenclature X
cell concentration (g L–1)
-
specific growth rate (h–1)
- m
maximum specific growth rate (h–1)
- D
dilution rate (h–1)
- S
concentration of growth rate-limiting nutrient (glutamate) (mmol L–1 or g L–1)
- Ks
substrate saturation constant (mol L–1)
- ms
maintenance coefficient (g g–1 h–1)
- Yx/s
theoretical yield of cells from glutamate (g g–1)
- Yx/s
yield of cells from glutamate (g g–1)
- YPT/s
yield of soluble PT from glutamate (mg g–1)
- YKDO/s
yield of cell-free KDO from glutamate (g g–1)
- YPT/x
specific yield of soluble PT (mg g–1)
- YKDO/x
specific yield of cell-free KDO (g g–1)
- qPT
specific soluble PT production rate (mg g–1 h–1)
- qKDO
specific cell-free KDO production rate (g g–1 h–1) 相似文献
9.
10.
M M Viadro L P Ivanitskaia L N Samo?lova M K Kudinova L E Bodunkova 《Antibiotiki i khimioterapii͡a》1989,34(5):378-382
A significant decrease in resistance to infections caused by gramnegative pathogens was observed in mice with neutropenia induced by cytostatics. Efficacy of schemes for combined chemotherapy with beta-lactams, aminoglycosides and a novel peptide antibiotic was studied on model infections in mice with neutropenia. In the neutropenic mice with sepsis caused by Pseudomonas the peptide antibiotic administered parenterally in a single dose of 50 micrograms/kg provided high therapeutic activity. In combination with azlocillin, cefotaxime and amikacin the peptide antibiotic has a synergistic therapeutic action. 相似文献