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1.
The rules of diagnostic kit elaboration for genetic typing of microorganisms, designed for epidemiological studies, have been shown in this paper. PCR MP method has been used for diagnostic kit elaboration. Well defined epidemiologically Enterococcus faecium strains have been applied as a research model. The optimisation of the method has been carried out using different amount of reagents and time of the particular stages. Critical parameters, which have significant influence on the quality of obtained results, have been assigned. Optimalised procedure, named PCR MP unique, has been validated for genetic typing of different species of microorganisms and its potential application for routine epidemiological studies. The PCR MP method has been successfully used for elaboration of diagnostic PCR MP unique-KIT, which allows intra-species differentiation of bacterial strains. The PCR MP unique-KIT enables fast, easy and cheap analysis of strains, using elementary laboratory equipment--gradient thermocycler.  相似文献   

2.
The different invasive and noninvasive diagnostic tests for Helicobacter pylori have been applied mainly in emerging countries. Molecular methods have been developed, especially a test for detection of H. pylori and its clarithromycin resistance directly from stools. The long-term effects of eradication on histologic lesions have been studied in a meta-analysis and the prognostic value of post-treatment in gastric mucosa-associated lymphoid tissue lymphoma has been assessed. An operating link for gastritis assessment (the OLGA staging) has also been published. Attempts to simplify the urea breath test protocol have been made, and new stool antigen tests have been proposed and compared to those previously available.  相似文献   

3.
In the present investigation an attempt has been made to study the phase response properties of monopolar chest lead ECG voltages. Using a generator model of the heart an equivalent circuit of ECG network has been developed. The equivalent impedance between WCT and probe electrode has been determined by reduction techniques. From this equivalent impedance the phasor characteristics of monopolar ECG voltages have been analysed for change in probe electrode locations. The source of the generated voltage, i.e., the heart, will develop a different voltage for its different condition. There will also be a change in impedances. Thus for the normal subject the distribution of the phasor of the ECG voltages will be different from that of the abnormal one. A software tool has been developed to evaluate the relative phase response of ECG voltages. The data acquisition of monopolar ECG records of chest leads V1 to V6 from chart recorder has been done with the help of AutoCAD application package. The harmonic constituents of ECG voltages have been evaluated at each harmonic plane and the phase characteristics have been studied in polar coordinate for normal subjects as well as for a typical case. An interesting result has been observed in typical cases which are indicated in the paper.  相似文献   

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5.
Chlorinated nitroaromatic compounds (CNAs) are persistent environmental pollutants that have been introduced into the environment due to the anthropogenic activities. Bacteria that utilize CNAs as the sole sources of carbon and energy have been isolated from different contaminated and non-contaminated sites. Microbial metabolism of CNAs has been studied, and several metabolic pathways for degradation of CNAs have been proposed. Detoxification and biotransformation of CNAs have also been studied in various fungi, actinomycetes and bacteria. Several physicochemical methods have been used for treatment of wastewater containing CNAs; however, these methods are not suitable for in situ bioremediation. This review describes the current scenario of the degradation of CNAs.  相似文献   

6.
The complex ecosystem of humans and microbes has been presented as an associative symbiosis based on a mutual support of symbionts with different consequences for them. Conditions for the persistence of bacteria have been defined: their resistance to environmental factors, antagonism in biocenosis, and stability to withstand host defense mechanisms. The key role of bacterial peptidoglycan has been defined for their survival in an infected organism, and the classification for persistent mechanisms of pathogens has been given. The group of bacterial secreted protease providing microbial resistance to defense factors of the organism has been described. Host colonizing resistance has been presented as a physiological regulatory system controlling bacterial penetration into an organism. Regulatory mechanisms for bacterial persistence have been discussed.  相似文献   

7.
Efficiency of linked cross-sectional scheme has been compared with pure longitudinal schemes for generalised estimation of norm relaxing the condition of constancy of variances. The relevant theory of estimation has been developed and the expression for the optimum estimators alongwith their variances have been derived. The percentage gain in efficiency has been calculated. It has been observed that for higher values of Q, percentage gain in efficiency of proposed scheme over cross-sectional is very high.  相似文献   

8.
A method of analysis for comparing the variability of two samples drawn from two populations has been developed. The method is also suitable for the nonnumeric form of data. A test based on ordered observations for testing the null hypothesis of equality of two variances has been given. The test statistic is a function of the sum of ranks assigned to smaller size sample. Ranking procedure has been modified to depict the variability in the data by the sum of ranks. The null distribution of the test-statistic has been worked out for small samples and it turns out to be chi-square distribution for large samples. The analytical procedure has been explained by a numerical example on the productivity and production of rice and wheat in India from 1950–51 to 1983–84.  相似文献   

9.
Kinetic expressions for the fermentative production of relatively high concentrations [12% (w/v)] of ethanol have been examined. Several expressions which account for both substrate and product inhibition have been formulated, and have been applied to suspended cell and immobilized cell reactors. Experimental data have been used to validate the kinetic expressions used, and the impact of combined inhibition on optimal reactor configuration has been assessed. The process implications of combined substrate and product inhibition for suspended and immobilized cell systems have been discussed.  相似文献   

10.
Activity coefficients of counterions in solutions of diethylaminoethyl dextran hydrochloride have been determined. It has been observed that they increase with decreasing concentration of the polyelectrolyte. The experimental values have been compared with those calculated using Oosawa's theory of activity coefficients. The calculated values are higher than those observed, which suggests that the rodlike model on which Oosawa's theory is based is inadequate for the present case. Activity coefficients of counterions of some solutions containing NaCl and KC1, respectively, have also been determined. It has been found that the additivity rule for activity of counterions applies for these solutions.  相似文献   

11.
Data selected from the questionnaire supplied by the 14 centres of vascular surgery have been analysed. All operated patients have been followed-up for 5 years. An analysis revealed that long-term oral anticoagulant therapy following vascular grafting statistically significantly improved the outcome of surgery in comparison with patients who have not been given oral anticoagulants. There has been no such a relationship, if antiaggregation agents had been used for the treatment.  相似文献   

12.
The method for analysis of microorganisms for the presence of the modification-restriction systems has been developed. The method has permitted to detect more than 10 new producing strains of restrictases including microorganisms of Rhizobium genus. Some of them are promising for practical use. It has been shown that using selection of clones the strain productivity can be increased. The purification process for the majority of restrictases has been proposed. Some physical and catalytic properties of new enzymes have been studied.  相似文献   

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14.
Profiles of endogenous peptides of the brain, heart, lungs, and spleen of a rat have been obtained by chromatographic and mass spectrometric analysis of low-molecular-mass fractions of tissues extracts. The concentrations of the corresponding components have been estimated from the intensities of 119 major chromatographic peaks. The total content of peptides in tissues, nmol/g (mg/g), was 3–13 (0.005–0.05) for the brain, 7–27 (0.01–0.10) for the heart, 17–68 (0.02–0.25) for the lungs, and 80–300 (0.08–1.30) for the spleen. A comparative analysis of the data obtained for the organs has been performed. The primary structures for 68 peptides have been determined; most substances (>70%) have been identified as hemoglobin fragments. It has been shown that many of the peptide components identified (>75%) are common for several organs. The relationship between the composition, the mechanism of formation, and the functional role of peptidomes of the organs, tissues, and cells of higher organisms has been discussed.  相似文献   

15.
Summary The action of glycine as an inhibitor to different species of methylotrophic bacteria possesing the serine pathway has been shown. With all the strains, glycine-resistant mutants have been obtained. A comparative study of growth parameters for both the mutant and wild strains has, been made. Better gram negative strains have been isolated but the same cannot be said for the gram positive strains.  相似文献   

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17.
Toxicity of cycads   总被引:1,自引:0,他引:1  
This is a review of the literature on the use of cycads as food and medicine, with special attention to their toxic properties. In the tropics and subtropics, where the plants are indigenous, their toxicity has long been known. Both gastrointestinal and neurological effects have been reported. Although several toxic components of the plants have been investigated, none has yet been shown to be responsible for specific effects. No lesion has been demonstrated to account for the progressive and apparently irreversible posterior paralysis which reputedly follows consumption of the plants by cattle. Current interest in the toxicity of the cycads has been stimulated by recognition of the high incidence of neurological diseases in an area of the world where they are used as food.  相似文献   

18.
Conformational analysis, by the method of atom-atomic potentials, has been carried out for five tripeptides containing gamma-glutamyl bonds and having general formula Glu(gamma)-X-Gly. The spatial structures have been determined and the changes arising on varying the second residue have been analyzed. A comparison of possible conformations and biological activity in respect to a number of enzymes allows to conceive what structural features of these compounds are important for the substrate specificity of the enzymes. In particular, the active site topography has been surmised for glutathione synthetase (EC 6.3.2.3) and gamma-glutamyltranspeptidase (EC 2.3.2.2). The glutathione thiol group has been found to be exposed in all possible conformations that explains its accessibility for various reagents.  相似文献   

19.
For estimation of growth, the efficiency of linked cross sectional scheme has been compared with pure longitudinal and cross sectional schemes. The relevant estimation theory has been developed and the expressions for the optimum estimators alongwith their variances have been derived. It has been observed that for estimation of growth, the linked cross-sectional scheme has been observed to be less efficient as compared to pure longitudinal scheme but more efficient than pure cross-sectional scheme.  相似文献   

20.
The kinetics of pepsin initiated coagulation of kappa-casein have been studied at pH 5.8. The primary and secondary phases of coagulation are shown to proceed simultaneously. The theory of enzymatically initiated clotting reactions proposed by Payens (Payens, T.A.J. (1976) Neth. Milk Dairy J. 30, 55--59) has been applied to this clotting system and has been used to obtain rate constants for the secondary phase of coagulation. As expected, clotting rate constants for kappa-casein increase with pepsin concentration. An activation energy of 30.6 kcal/mol has been obtained for the secondary phase of coagulation. Turbidity measurements are a convenient means for studying the secondary phase of coagulation but do not provide an unambiguous means for studying the primary phase of the reaction.  相似文献   

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