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It is shown that in summer the level of sodium, potassium and calcium in the colostrum and milk serum of cows for the first ten days of lactation is 1.5-2.0 times higher and the content of inorganic phosphorus lower than the analogous indices for cows in winter-spring. The concentration of iron, copper, zinc and chlorides in the colostrum and milk serum of cows in different seasons is unchanged.  相似文献   
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The hybrid plasmid pOV13 proposed as a potential vector for DNA cloning in a broad bacterial host range has been constructed on the basis of the broad host range plasmid RSF1010 and a shortened derivative of RP4, the plasmid pVZ115 serving a marker DNA fragment. The plasmid pOV13 contains the genes for streptomycin, kanamycin and tetracycline resistance and single cleavage sites for restriction endonucleases BamHI, BgIII, SalI, SmaI, PvuII, XhoI, as well as double cleavage sites for restriction endonucleases PstI and HindIII permitting one to clone DNA with insertional inactivation of genes. The physicogenetical map of the birepliconed plasmid pOV13 is presented.  相似文献   
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Sodium, potassium, calcium, magnesium, manganese, zinc and chloride contents in the blood plasma of calves at parturition have been established to correspond to their levels in blood of cows during their calving period. Iron and inorganic phosphorus contents in calves blood plasma appeared to increase and copper content to be lower in this period as compared to postnatal period. By the third day of postnatal ontogenesis sodium concentration in calves blood decreased, copper level increased and the rest indices of water-salts metabolism in calves and adult animals were alike. Digestion disturbances in the calves were accompanied by changes in levels and magnitude of Na+/K+ ratio, magnesium, iron, copper, manganese and zinc contents in blood, liver and kidneys as well as Ca++/Pi ratio in mitochondria and cytosol of liver and jejunum mucose layer cells in comparison with clinically healthy animals.  相似文献   
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Plasmid, designated pFT15/10-1, was isolated from Francisella tularensis vaccine strain 15/10. The plasmid is presented by the homogeneous 5.02 +/- 0.054 Md monomeric circular DNA molecules in electron microscopic preparations. Plasmid size is 7-7.3 kb as defined by electrophoresis in agarose gel. The restriction analysis has revealed that plasmid pFT15/10-1 possesses a single specific cleavage site for restriction endonuclease EcoRI, two sites for restriction endonucleases BamHI, BgIII, HincII, HindIII, PstI, three sites for BglI and SalI, some for AluI, TagI, MvaI, CfrI. Plasmid is not digested by restriction endonucleases SmaI, XmaI, KpnI, MluI. Restriction map of the plasmid was constructed for most frequently used restriction endonucleases.  相似文献   
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The content and intensity of incorporation of 3H-uridine in RNA of chromosomes, nucleoli and cytoplasm isolated by microsurgery from the salivary glands of larvae and prepupae of Chironomus thummi were studied following the incubation of salivary glands in the Cannon's medium with 3H-uridine. It was shown that during metamorphosis the content of RNA and intensity of 3H-uridine incorporation decrease in the nucleolus and cytoplasm in a prepupa, as compared with a larva, and suffer no changes in chromosomes in spite of much larger size of many puffs in a prepupa. The patterns of RNA synthesis in the salivary glands of larvae during metamorphosis are discussed.  相似文献   
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Treatment of patients diagnosed as schizophrenic with antipsychotic drugs (neuroleptics) is known to cause occasional unexplained depletion of white blood cells, especially neutrophil granulocytes. It has been known for many years that neuroleptics can interfere with the mitochondrial respiratory chain in vitro. Because there has been a growing interest recently in mitochondrial targeting of drugs, and since a quantitative structure-activity relationship (QSAR) model that predicts mitochondrial accumulation of neuroleptics has been published, we investigated the effects of neuroleptics on white blood cell mitochondria. Venous blood samples were collected from both patients undergoing treatment with neuroleptics and healthy volunteers. The samples were processed for transmission electron microscopy. The resulting images of white blood cells were analyzed using stereology to compare quantitatively mitochondrial morphology in the patient and control groups. We found that in patients, but not in controls, there was swelling of mitochondria and fragmentation of the mitochondrial cristae. There also were fewer mitochondria in patients than in controls, although due to the swelling of the organelles, the volume density of mitochondria in the two groups was not significantly different. Such changes are typical of a toxic insult. Consequently, it seems plausible that, since schizophrenia is not a disease considered to affect white blood cells per se, these changes probably are due to the medication.  相似文献   
8.
Using light microscopy, we have shown that chlamydia and/or chlamydia-like microorganisms are registered in 20-25% of the healthy part of human population, whereas in patients of the same age with gynecological problems these were found in 40-50%. Commonly, the infection was slightly manifested (less than 5% of cells are infected). These results were confirmed in four months but only in heavily infected patients. The light microscope data are confirmed by observations with electron microscopy, and by FISH hybridization of the total chlamydial DNA on cytological preparations with chlamydial inclusions. In some cases, microcolonies revealed by FISH hybridization occupied the majority of the cytoplasm volume. Occasionally, the DNA material was found on the nuclear surface. It seems likely that in heavily infected cells chlamydia are able to penetrate into the perinucular space.  相似文献   
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