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41.
Andrzej J. Żelazowski Jadwiga A. Szymańska Czesklaw S. Cierniewski 《Chemico-biological interactions》1980,33(1):115-125
Two homogenous fractions of hepatic metallothioneins ((Cd,Zn) MT-1 and (Cd,Zn) MT-2) and renal metal binding proteins ((Bi,Cu) BP-1 and (Bi,Cu) BP-2) were isolated from rats exposed to heavy metals and specific antisera to them were produced in rabbits.These antisera were tested by immunodiffusion and immunoelectrophoresis for their ability to bind different fractions of hepatic Cd,Zn -metallothionein and renal (Bi,Cu)-, (Hg,Cu)- and (Cd,Cu)-binding proteins. It was found that anti (Bi,Cu) BP antisera did not cross-react with hepatic (Cd,Zn) MT-1 and (Cd,Zn) MT-2. Strong immunological cross-reactions were detected between anti (Bi,Cu) BP antisera and individual forms of (Cd,Cu)-, (Hg,Cu)- and (Bi,Cu)-binding proteins isolated from rat kidneys. 相似文献
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43.
Andrzej Paszewski Wiesawa Pramo Magorzata Landman-Baliska 《Molecular & general genetics : MGG》1977,155(1):109-112
Summary Mutants of Aspergillus nidulans blocked in the main pathway of cysteine synthesis show an elevated level of the enzymes involved in the synthesis of cysteine from homocysteine i.e. cystathionine -synthase and -cystathionase and a depressed level of homocysteine methyltransferase. This results in a considerable change in the sulfur amino acids pool as compared to the wild type. Upon addition of cysteine to the growth medium the first two enzymes are repressed while the level of the third one increases. These data indicate that the two diverging pathways of homocysteine metabolism are anti-coordinately regulated. 相似文献
44.
Summary The nervous system of the most primitive fresh-water Turbellaria of the order Catenulida was investigated. Neurosecretory
cells were found to occur in it. These cells have a structure similar to that of nerve cells, they only differ by the presence
of neurosecretion granules and a more developed golgi complex. In the simplest Catenulida,Stenostomun, neurosecretory granules are found both in the brain cells and in the trunks in the nerve fibres where they are rather randomly
distributed. Another representative of this family, the more highly organizedCatenula, exhibits specialized brain and nerve trunk regions containing neurosecretion granules.
This work was supported in part by the Committee on Cytobiology of the Polish Academy of Sciences 相似文献
45.
Andrzej Myśliwski Jolanta Myśliwska Zbigniew Kmieć 《Histochemistry and cell biology》1977,52(1):91-96
Summary A comparsion of the Feulgen hydrolysis curves and the chromatin compactness of the liver cell nuclei of young and old rats was made. It was found that the rate of DNA depurination and chromatin compactness are higher in the liver cell nuclei of old rats, both in di-and tetraploidal cells. The effect of fixation upon the course of the hydrolysis curves is discussed.This investigation was supported by grant 474/VI Committee of Cell Pathology, Polish Academy of Sciences 相似文献
46.
Some opiates with morphinan- and benzomorphan-structures possess affinities for neuroleptic receptors as revealed by their abilities to compete with 3H-spiroperidol for common binding sites in rat striatum (IC50 in the range between 10?6 and 10?5M). The binding of these opiates to neuroleptic receptors appears to be of pharmacological significance, since studies in mice revealed a small but significant displacement of spiroperidol by high doses of the opiate antagonist levallorphan from specific binding sites in the striatum. In addition, there exists some correlation between the ability of opiates to bind to neuroleptic receptor sites and their potency to evoke “bizarre behavior” in rats . In contrast, a wide variety of other opiates having morphine-, morphinone- or oripavine-structure showed no affinity for neuroleptic binding sites (IC50 greater than 10?4 M). Of the opioid peptides (methionine-enkephalin, leucine-enkephalin and β-endorphin) none has an affinity for neuroleptic binding sites. A variety of other peptides were also investigated but did not interfere with spiroperidol binding. Only ACTH showed a moderate affinity for neuroleptic binding sites. 相似文献
47.
CD study of four modified nucleosides, constituents of tRNA molecules, revealed that 2-thio-5-methyluridine and 5-methyluridine in aqueous solution, 0.1N HCl, and organic solvents essentially occur in an anti-conformation. 5-Methylcytidine also occurs in an anti-conformation similar to cytidine in aqueous solution and organic solvents, while 2-thiocytidine dihydrate appears to occur in an anti-conformation. It is stressed that the CD data of thionucleosides might be applied to the successfully conformational analysis of tRNA molecules. 相似文献
48.
Andrzej Slominski 《In vitro cellular & developmental biology. Animal》1991,27(9):735-738
Summary Crosslinking of [14C]l-tyrosine to at least five hamster melanoma cell surface proteins is reported. This effect was abolished by addition of nonradioactivel-tyrosine,l-phenylalanine, orl-dopa, but not byd-tyrosine, tyramine, dopamine, norepinephrine, or epinephrine. The above proteins can be purified by tyrosine-affinity chromatography.
They have molecular weights different from proteins staining for dopa oxidase and proteins that bind anti-tyrosinase antibody
in Western blots. It is suggested that they may be a hithergo unrecognized part of the cellular apparatus governing melanogenesis. 相似文献
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