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Summary The growth of microorganisms in the nutrient solution of a circulating hydroponic system was suppressed by ultra-violet radiation. Applied for three hours daily (572 Jm−2 h−1) throughout experiments in which tomato and corn were grown, it was effective in reducing the population of microorganisms from between 500–800·103 to 10–50·103 cells per ml. 相似文献
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G M Bolgareva E K Krivtsova Iu A Revazova N S Zakharova I G Bazhanova T N Remova E I Shmeleva N U Mertsalova E E Sukhinova E S Revazova 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1992,(7-8):42-45
Two vaccine preparations obtained from Bordetella pertussis, whole-cell vaccine constituting one of the components of adsorbed DPT vaccine and acellular vaccine, were tested for mutagenicity. The doses of the preparations covered the range 1-100 ED50. Ames' test and the metaphase analysis of marrow cells of C57BL/6J mice were used. The acellular preparation was also tested on thymectomized mice, taking into consideration chromosomal aberrations in marrow metaphases. Whole-cell and acellular pertussis vaccines did not induce mutations in Salmonella typhimurium and chromosomal aberrations in mouse marrow cells. 相似文献
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Bass MG Sokolova VA Kustova ME Grachyova EV Kidgotko OV Sorokin AV Vasilyev VB 《Biochimica et biophysica acta》2006,1757(5-6):679-685
Gross alterations in cell energy metabolism underlie manifestations of hereditary OXPHOS (oxidative phosphorylation) diseases, many of which depend on proportion of mutant mitochondrial DNA (mtDNA) in tissues. An animal model of OXPHOS disease with maternal inheritance of mitochondrial heteroplasmy might help understanding the peculiarities of abnormal mtDNA distribution and its effect on pre- and postnatal development. Previously we obtained mice that carry human mtDNA in some tissues. It co-existed with murine mtDNA (heteroplasmy) and was transmitted maternally to the progeny of animals developed from zygotes injected with human mitochondria. To analyze the probability of obtaining heteroplasmic mice we increased the number of experiments with early embryos and obtained more specimens from F1. About 33% of zygotes injected with human mtDNA developed into post-implantation embryos (7th-13th days). Lower amount of such developed into neonate mice (ca. 21%). Among post-implantation embryos and in generations F0 and F1 percentages of human mtDNA-carriers were ca. 14-16%. Such percentages are sufficient for modeling maternally inherited heteroplasmy in small animal groups. More data are needed to understand the regularities of anomalous mtDNA distribution among cells and tissues and whether heart and muscles frequently carrying human mtDNA in our experiments are particularly susceptible to heteroplasmy. 相似文献
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A detailed method for obtaining preparations of human sperm chromosomes 总被引:15,自引:0,他引:15
R H Martin 《Cytogenetics and cell genetics》1983,35(4):252-256
A detailed technique is described for obtaining preparations of the chromosome complements of human sperm by fertilization of hamster eggs and analysis of the male pronucleus. Some of the more difficult aspects and important steps are emphasized. Technical data from 17 consecutive experiments are presented to provide an estimate of the number of karyotypes which can be obtained in an experiment. 相似文献
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Abramzon OM Kartashova OL Valyshev AV Perunova NB Valysheva IV Bukharin OV 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2004,(3):7-10
In the study of 65 microbial cultures isolated from the purulent foci in acute pulmonary abscess and acute pyothorax of 48 patients, a wide spectrum of microflora was detected. Staphylococci and Pseudomonas prevailed among aerobes, bacteroids and peptostreptococci--among anaerobes. In cases of the prolonged course of the pathological process, as compared with the common one, microorganisms exhibited hemolytic activity and high antilysozyme and anticomplementary levels. These findings served as the basis for working out a mathematical model for the prognosis of the disease course with 95% probability. 相似文献
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K G Gapochko O P Misnikov V I Moskalenko 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1988,(4):45-50
In this work the methods for the passive control and automatic regulation of the concentration of vaccinal aerosols in static chambers are analyzed. For such analysis, a method for the calculation of the parameters of vaccinal aerosols, taking account of the law of the distribution of particles by their sizes and of the processes of sedimentation and inactivation of microbial aerosols, has been developed. To make empirically established coefficients more precise, the necessary experimental studies have been carried out. High effectiveness of the method providing for the regulation of aerosol mass concentration has been demonstrated, and conditions necessary for effective aerosol immunization have been established. 相似文献
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N N Zhukov-Verezhnikov P I Anisimov N S Goncharova G M Bochko Z N Karaseva 《Biulleten' eksperimental'no? biologii i meditsiny》1976,82(8):961-962
There proved to be a serological similarity between the antigens of the human small intestine, the stomach and the liver, and the antigens of various cholera vibrio fractions. No antigenic similarity was revealed in examination of the heart and kidney. Heterogenous antigen was found not only in the somatic V. cholerae antigen, strain 569 (B), but also in the cholerogen-toxoid obtained from it. At present it is the most widespread prophylactic preparation. 相似文献
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L A Piruzian E M Mikha?lovski? 《Izvestiia Akademii nauk SSSR. Seriia biologicheskaia》1990,(6):835-844
Published data on interactions of some psychotropic drugs with immunocompetent target cells has been reviewed. The observed immunosuppressive, immunostimulating, and immunomodulating activities of the drugs are considered nontraditional. The necessity of more detailed study of mechanisms of such interactions is outlined. Possible use of psychotropic drugs as immunomodulators is proposed. 相似文献
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A simple, accurate, and robust quantitative capillary electrophoresis (CE) method for the determination of oversulfated chondroitin sulfate (OSCS) as a contaminant in heparin (Hep) preparations is described. After degradation of the polysaccharides by acidic hydrolysis, the hexosamines produced (i.e., GlcN from Hep and GalN from OSCS) were derivatized with anthranilic acid (AA) and separated by means of CE in approximately 10 min with high sensitivity detection at 214 nm (limit of detection [LOD] of ∼200 pg). Furthermore, AA-derivatized GlcN and GalN showed quite similar molar absorptivity, allowing direct and simple quantification of OSCS in Hep samples. Moreover, a preliminary step of specific enzymatic treatment by using chondroitin ABC lyase may be applied for the specific elimination of interference in the analysis due to the possible presence in Hep samples of natural chondroitin sulfate and dermatan sulfate impurities, making this analytical approach highly specific for OSCS contamination given that chondroitin ABC lyase is unable to act on this semisynthetic polymer. The CE method was validated for specificity, linearity, accuracy, precision, LOD, and limit of quantification (LOQ). Due to the very high sensitivity of CE, as little as 1% OSCS contaminant in Hep sample could be detected and quantified. Finally, a contaminated raw Hep sample was found to contain 38.9% OSCS, whereas a formulated contaminated Hep was calculated to have 39.7% OSCS. 相似文献
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To help us understand the factors and mechanisms implicated in the death of microorganisms or their resistance to temperature in a low water activity environment, microorganisms were dried on the surface of glass beads before being subjected to high temperatures for a short period followed by rapid cooling. Two microorganisms were studied: the yeast Saccharomyces cerevisiae and the bacterium Lactobacillus plantarum. Experiments were carried out at 150, 200, and 250 degrees C, with four durations of heat treatment and seven levels of initial water activity between 0.10 and 0.70. We observed an unexpected range of water activity, between 0.30 and 0.50, at which microorganisms were more resistant to the various treatments, with maximal viability at 0.35 for L. plantarum and 0.40 for S. cerevisiae. 相似文献
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Male-specific (F+) coliphages have been proposed as a candidate indicator of fecal contamination and of virus reduction in waste treatment. However, in this and earlier work with a laboratory thermophilic anaerobic digester, a heat-resistant fraction of F+ coliphage populations indigenous to municipal wastewater and sludge was evident. We therefore isolated coliphages from municipal wastewater sludge and from biosolid samples after thermophilic anaerobic digestion to evaluate the susceptibility of specific groups to thermal inactivation. Similar numbers of F+ DNA and F+ RNA coliphages were found in untreated sludge, but the majority of isolates in digested biosolids were group I F+ RNA phages. Separate experiments on individual isolates at 53 degrees C confirmed the apparent heat resistance of group I F+ RNA coliphages as well as the susceptibility of group III F+ RNA coliphages. Although few F+ DNA coliphages were recovered from the treated biosolid samples, thermal inactivation experiments indicated heat resistance similar to that of group I F+ RNA phages. Hence, F+ DNA coliphage reductions during thermophilic anaerobic digestion are probably related to mechanisms other than thermal inactivation. Further studies should focus on the group III F+ RNA coliphages as potential indicators of reductions of heat-resistant pathogens in thermal processes for sludge treatment. 相似文献
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S-adenosylmethionine decarboxylase (AdoMetDC) is a key enzyme in the biosynthesis of the polyamines spermidine and spermine. Polyamines are ubiquitous organic cations that are absolutely required for normal cell proliferation and differentiation. AdoMetDC catalyzes decarboxylation of S-adenosylmethionine (AdoMet) which provides aminopropyl groups for spermidine and spermine synthesis. Mammalian AdoMetDC is produced as a proenzyme (38 kDa) which is cleaved to form the alpha (30.7 kDa) and beta (7.7 kDa) subunits of the mature enzyme. It is here shown that the catalytic activity of the enzyme was completely eliminated when lysine 12 was mutated to an arginine residue in the small subunit; however, the proenzyme processing was not affected. On the other hand, mutations of other lysine residues (Lys45-->Arg and Lys56-->Arg) did not affect either the enzyme activity or the proenzyme processing. Structure analysis using Swiss Deep Viewer v3.7 has indicated that Arg in place of Lys12 may eliminate AdoMetDC activity by restricting the mobility of Thr85 through hydrogen bonding. Sequence alignment of various AdoMetDC sequences indicated that Thr85 is in a highly conserved region, suggesting that Thr85 is critical for the decarboxylation reaction. 相似文献
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Charles W. Parker Del A. Koch Mary M. Huber Sandra F. Falkenhein 《Prostaglandins & other lipid mediators》1980,20(5):887-908
Type II B arylsulfatases are known to inactivate slow reacting substance (SRS), but the mechanism is unclear. In the present study, ordinary commercial preparations of Sigma limpet arylsulfatase largely inactivated the glutathionyl and cysteinyl-glycyl forms of SRS, but the cysteinyl form of SRS was largely resistant to the enzyme. Evidence is presented which established that a major mechanism for the inactivation of the glutathionyl and cysteinyl-glycyl SRS types, at least by the particular enzyme preparations we have studied, involves cleavage of the glycine moiety from the sulfur containing side chain. This was confirmed by digestion studies with glutathione itself. In addition, there is ome evidence to indicate that the enzyme may destabilize the double bond structure of the SRS molecule, contributing to the overall inactivation. 相似文献
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Production of recombinant proteins in suspension cultures of genetically modified plant cells is a promising and rapidly developing area of plant biotechnology. In the present review article, advantages related to using plant systems for expression of recombinant proteins are considered. Here, the main focus is covering the literature on optimization of cultivation conditions of suspension-cultured plant cells to obtain a maximal yield of target proteins. In particular, certain examples of successful use of such cells to produce pharmaceuticals were described. 相似文献
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V E Matveev V M Tarasenko A A Vorob'ev 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1977,(12):77-83
The paper treats of some problems pertinent to modelling of thermal inactivation of the microbes serving as a theoretical foundation for the achievement of guaranteed sterility of the equipment, communications and fluids. The principal attention is devoted to the problems of quantitative assessment of the efficacy of the mentioned processes. The advantages and the drawbacks of some deterministic and probability models which found application in microbiological laboratories are assessed. The expediency of orientation on a model proposing the use of characteristics of thermal resistance of the microorganisms and considering the heterogeneity of the actual populations by the thermoresistance index was demonstrated. 相似文献