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1.
An approach to the synthesis of cationic carbohydrate surfactants with potential antimicrobial and transfecting activities is proposed.  相似文献   
2.
The present paper has analyzed relationship between sympatico-adrenal and opioid systems in the pathogenesis of stress heart damage. Based on the our own results and other investigator data the authors make a conclusion that namely relationship between opioid and sympatico-adrenal systems both on the level of the brain and on the periphery determines a degree of the heart resistance to the injury action of severe stress. Myocardial protection by opioids at stress was found to be mediated by the peripheral mu-opioid receptors and was associated with decrease in an activity of sympatico-adrenal system and a inhibition of its effector part. On contrary central opioid system activation leads to an increase in stress heart damage via an increase in sympathetical influence on the myocardium.  相似文献   
3.
D A Maslov  L Simpson 《Cell》1992,70(3):459-467
Seventeen kinetoplast minicircle-encoded and nine maxicircle-encoded gRNA genes have been identified. Six overlapping minicircle-encoded gRNAs mediate editing for the 5'-pan-edited MURF4 gene and two for the 5'-edited COIII gene. The pan-edited RPS12 mRNA is edited by seven minicircle-encoded gRNAs and one maxicircle-encoded gRNA. The 3'-most gRNA in each domain forms an anchor with unedited mRNA, whereas upstream gRNAs form anchors only with edited mRNA, thereby explaining the observed 3' to 5' polarity of editing within an editing domain. We suggest that a role of G-U base pairs is to allow breathing of the edited mRNA-gRNA hybrid and formation of the upstream anchor hybrid.  相似文献   
4.
The ultrastructure and respiratory activity of mitochondria in rice coleoptile grown in the presence and in the absence of an inibitor of mitochondrial protein synthesis (chloramphenicol) have been studied. It is shown that during the first 48 h of germination a rapid development of mitochondrial cristae takes place without notable influence of chloramphenicol on biogenesis of mitochondria. But the presence of the inhibitor has a significant effect in the subsequent period (48-144 h): a gradual and almost complete reduction of mitochondrial cristae is observed. These unusual "noncristate" mitochondria, although greatly lacking cytochrome oxidase, have a high respiratory activity. The respiration of "noncristate" mitochondria is resistant to KCN. It is supposed that chloramphenicol-induced rice coleoptile can be used as a new convenient object for studies of the nature of alternative oxidase as well as the biogenesis of mitochondria with cyanide-insensitive respiration.  相似文献   
5.
Russian Journal of Bioorganic Chemistry - The main classes of antitumor drugs (antimetabolites, anthracyclines, taxanes, and alkylating agents) act via DNA damage, inhibit DNA synthesis, and/or...  相似文献   
6.
The basic causes of death in hoofed mammals in the Urruri reserve and in the adjacent territory during the period from 1974 to 2011 are hunting and poaching, tiger predation, and exhaustion. The sika deer has accounted for the largest number of the established deaths since the 1990s, because this species has become dominant in the fauna of hoofed animals in the reserve as a result of acclimatization. Before the 1980s, the main prey for tigers were the red deer (52%) and wild boar (44%): the share of the sika deer in the prey was 4%. During the most recent 10 years, the share of the sika deer, wild boar, and red deer in the tiger-prey trophic link at separate stations of the reserve has been 68%, 20.6%, and 6.9%, respectively.  相似文献   
7.
Russian Journal of Plant Physiology - The earlier-detected effect of the mineral nitrogen form in the nutrient medium (ammonium or nitrate) on the quantity of ribosomes in the cells of...  相似文献   
8.
9.
The informatory role of a new marker of HIV infection, characterizing the content of HIV-1 RNA in the biological fluids of the patient's body, is evaluated. The quantitative determination of HIV-1 RNA, carried out in a single assay, was made in the blood of 25 HIV-infected patients. These studies confirmed that the determination of the level of RNA in the plasma (viral load) was a reliable criterion indicating the severity and progress of the disease. The viral load of more than 100,000 copies/ml was a sign prognosticating the future pronounced progress of the disease in spite of moderate clinical manifestations and relatively high values of CD4 cells in the patient's blood at the moment of testing.  相似文献   
10.
The experiments with the isolated rat heart demonstrated a significant decrease in reperfusion-induced damage of cardiomyocytes upon adding the selective 1 receptor agonist DPDPE (0.1 mg/l) to the perfusion solution. On the contrary, no cardioprotective effect was observed for 0.5 mg/l concentration of the peptide or after its intravenous injection. Stimulation of the cardiac 1 opioid receptors by intravenous injection of 0.5 mg/kg DPDPE or its addition to the perfusion solution decreased myocardial contractility both under conditions of normal oxygenation and during reperfusion. Thus, the cardioprotective and negative inotropic effect of DPDPE is mediated by activation of the cardiac 1 opioid receptors.  相似文献   
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