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121.
Faeces and raw milk from individual cows were examined for the presence of Campylobacter jejuni . After drawing milk, the lactoperoxidase system was inactivated by raising the pH to 7.5. The organism was isolated from 22% of 904 faecal samples and from 4.5% of 904 milk samples. From laboratory experiments it could be concluded that inactivation of the lactoperoxidase system resulted in a better isolation of C. jejuni from raw cows' milk.  相似文献   
122.
123.
For isolating a highly active variant of the butirosin-producing culture, a strain forming trace amounts of the antibiotic substance was used. Exposure to nitrosomethylbiuret and nitrosoguanidine and the use of selective media containing streptomycin and butirosin resulted in a 30-fold increase in the strain productivity. Thin layer chromatography of the produced antibiotic substance in the solvent system developed by the authors, mass spectrometry and assay of the antimicrobial spectrum in regard to ++gram-positive and ++gram-negative bacteria by using the known aminoglycosidine-inactivating enzymes revealed that the substance was identical to butirosin. Along with the major product, the fermentation broth contained up to 5 per cent of ribostamycin.  相似文献   
124.
An analysis of the results of the examination and treatment of 379 patients undergoing transthoracic interventions showed that the use of the target-aimed selective immunomodulation, short-term antibacterial prophylaxis, inhibitors of arachidonic acid metabolites, active elimination of the circulating immune complexes and medium-weight molecular peptides and adequate local analgesia after the interventions providing normalization of the laryngeal reflex and early activation of the patients permitted the incidence of the pulmonary complications to be decreased by 2.5 times, pleural complications by 1.7 times, suppuration of the postoperative wound by 1.8 times and the total expenses by 25.6 per cent.  相似文献   
125.
126.
Summary Linkage studies and cytogenetically visible deletions associated with nonspecific X-linked mental retardation (XLMR) and a specific form of deafness (DFN3) have indicated that the genes responsible for these disorders are located at Xq21. Using DNA probes from this region, we have studied several overlapping deletions spanning different parts of Xq21. This has enabled us to assign the DFN3 gene and a gene for nonspecific XLMR to an interval that encompasses the locus DXS232 and that is flanked by DXS26 and DXS121.  相似文献   
127.
The p53 gene has been associated with malignant transformation as well as "anti-oncogene" activity. In the present report expression of p53 in resting and activated human blood monocytes and lymphocytes is analyzed. It is found that human monocytes freshly isolated by continuous percoll gradient centrifugation contained detectable level of p53 mRNA. Stimulation of monocytes by potent activation inducer Staphylococcus Aureus Cowan I for 3-5 hr caused disappearance of r53 mRNA. In contrast, induction of high level of TNF-alpha mRNA was detected. Addition of cycloheximide had no effect on p53 mRNA content in stimulated monocytes, and caused disappearance of mRNA in resting cells. In lymphocytes cultures p53 mRNA was absent in freshly isolated cells and in resting lymphocytes cultured for 20 hr. Activation of lymphocytes by lectin caused accumulation of p53 mRNA. We suggest that r53 gene regulation and functions might be different in human monocytes and lymphocytes.  相似文献   
128.
I N Uryvaeva  G V Delone 《Ontogenez》1992,23(4):370-378
Latent genetic disturbances in aging liver cells can be registered during interphase by the appearance of micronuclei resulting from certain chromosomal aberrations. Micronuclei were also detected in postmitotic hepatocytes of mouse liver regenerating after partial resection of CCl4 poisoning. In 1.5- and 2-month-old mice, the proportion of micronuclei-containing cells was on average 0.59 and 0.89%, respectively. At the age of 4 and 7 months, the proportion of aberrant cells in hepatocyte population, including cells containing multiple micronuclei, increased to 5.93 and 11.7%, respectively. In order to evaluate parameters used to characterize "spontaneous" aging, experiments were performed in which genetic disturbances were induced by x-irradiation or treatment with dipin, an alkylating agent (individually or in combination); the effect was determined one and two months after the treatment. The yield of micronuclei under the conditions of a mild treatment (irradiation at a dose of 0.7 and 1.4 Gr or dipin at a dose of 30 mg/kg body weight) was similar to that observed during aging. The possible reasons for the increased (as compared to the published data) rate of genetic disturbances in arbitrary intact animals are discussed.  相似文献   
129.
The interaction of ovomucoid proteinase inhibitor prepared from duck egg white with a dextran of a molecular weight of 70,000 preliminary treated with potassium periodate. Irrespective of the number of the sites of the ovomucoid binding to aldehyde-dextran the anti-chymotryptic activity is equal to that of the native inhibitor, while the antitryptic activity decreases proportionally to the number of ovomucoid amino groups involved in the reaction with dextran. When a few ovomucoid molecules are immobilized on the polysaccharide macromolecule the perturbing effect of the protein-protein interactions is minimal, as the rigid polymeric chain prevents from the formation of associates of proteins immobilized on this backbone.  相似文献   
130.
A quick, sensitive and easily automatizable method for PCR amplification of genomic DNA eluted from dried blood spots is described. DNA is eluted from a 3-mm spot routinely used for neonatal screening of inherited diseases either by boiling or by sonication. A preliminary and brief spot-autoclaving step is mandatory to ensure optimal and reproducible PCR amplifications. Only 1% of the eluted DNA is required for PCR analysis allowing the execution of multiple genetic tests on the same blood spot. The method has been successfully applied to the detection of a known phenylketonuria-causing mutation and will facilitate the analysis of the genetic repository provided by Guthrie's cards stored in neonatal screening laboratories.  相似文献   
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