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Regularities in the concentration and distribution of basic forms of phosphorus such as mineral, organic, suspended and bound to iron in complexes with humic substances were determined for diverse Karelian water bodies. Seasonal variations of the concentrations of phosphorus forms in Karelian water bodies of different trophic status were found.

Home made and foreign preparations (6 patterns in each) were tested as microcarriers for cultivation of anchorage-dependent cells in the medium supplemented with 0.25% enzymatic hydrolysate of muscles and 10-20% animal serum. The best results were obtained with microcarriers DEAE-2.5, Cytodex-1, and DEAE-cellulose. Using home microcarriers DEAE-2.5, continuous swine embryo kidney cells and primary chick embryo cells yielded, respectively, 9-11 and 3-4 times increase.

A method of preparation of mitochondria free of nuclear DNA and its fragments by treatment of mitochondria with DEAE-cellulose has been developed. This method is based on binding nuclear nucleic acids and nucleoproteins to DEAE-cellulose particles in the media used for isolation of mitochondria. Treatment with DEAE-cellulose under the conditions described does not induce any visible degradation of mitochondria and mitochondrial DNA. The mitochondrial DNA preparations obtained from beef and rat liver are represented with closed circular molecules of contour length about 5.5 mu. The 5-methylcytosine content in beef and rat mitochondrial DNA (3.03 and 2.0 mole %, respectively) is twice as much as in corresponding nuclear DNA. Besides, mitochondrial DNA strongly differs from nuclear ones by a lower degree of pyrimidine clustering: the amount of mono- and dipyrimidine fragments (about 32 mole %) in mitochondrial DNA is 1.5 times as large and the content of long pyrimidine clusters (hexa- and others) is 2--4 times as low as those in nuclear DNA. The methylation level and the pyrimidine clustering degree may be used as criteria for the purity of mitochondrial DNA from nuclear DNA.

Inclusion of an additional treatment of the products obtained at centrifugation stages b1 and b13 with activated bentonite and aluminium hydroxide into the alcohol method for the production of immunoglobulin from placental and abortion blood permits obtaining preparations with lowered content of proteolytic enzymes and thermostable acid phosphatase, free from chorionic gonadotropin and blood pigment. The treatment of the final preparation with DEAE cellulose removes blood group antigens from immunoglobulins. The preparations obtained by this method have been shown to meet the requirements for immunoglobulins imposed by technological specifications.