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1.
M A Dotsenko I A Aiusheva R I Rudneva V I Korol'kov 《Aviakosmicheskaia i ekologicheskaia meditsina》2007,41(6):53-56
Head-down tilting of primates (HOT) is a universal method of studying the hypokinetic syndrome effects on functionality of various body systems. Clinical biochemical blood assay was performed in a 25-day HDT experiment (-5 degrees) with 11 Macaca rhesus. One group of animals was kept tilted all the time through, whereas the other was periodically returned into the orthostatic position for 30 to 120 minutes 4-5 times a week. Dry chemistry was employed in biochemical analysis of blood serum and enzyme immunodetection (EID) in measuring blood hormones. As a rule, the biochemical parameters of primates' serum were within the physiological norm range. Shifts in protein, carbohydrate and mineral metabolism were sought for and enzymic activity in blood serum and hormone concentrations were determined. HDT did not produce noteworthy changes in blood concentrations of somatotropic hormone, thyrotrophic hormone (TTH), triiodothyronine (T3), thyroxine (T4) or cortisol. Animals of both groups showed statistically reliable decrease in blood osteocalcine. The preventive complex did not contribute materially to the control of metabolic homeostasis and endocrine function of the primates adapting to the 25-day HDT. 相似文献
2.
用体外培养的人的伪表皮作为模型,进行药物毒理学作用的研究,观察了二甲亚砜(DMSO)在不同浓度和不同接触时间条件下,对人的伪表皮细胞脱氧核糖核酸(DNA)、核糖核酸(RNA)和蛋白质合成的影响:随着接触时间的延长,DNA、RNA和蛋白质合成均受抑制。低浓度条件下(1%),DNA、RNA和蛋白质合成增加;在15~50%浓度下,DNA和蛋白质合成抑制,而RNA合成仍增加;在高浓度条件下(70%~100%),DNA、RNA和蛋白质合成均明显抑制。 相似文献
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Telfer JF; Thomson AJ; Cameron IT; Greer IA; Norman JE 《Human reproduction (Oxford, England)》1997,12(10):2306-2312
Superoxide, an agent which attenuates the half-life of nitric oxide, is
metabolized and synthesized by superoxide dismutase (SOD) and xanthine
oxidase, respectively. Over the last few years much work has focused on the
role of nitric oxide in human parturition. The aim of this study was to
determine whether the onset of human parturition is associated with a
change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD),
manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the
uterus. Samples of myometrium, placenta, decidua and fetal membranes were
obtained from women before and after the onset of labour at term.
Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine
oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like
immunoreactivity was detected in syncytiotrophoblast cells, villous stromal
cells and endothelial cells of blood vessels in the placenta. In the
myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial
cells and to some vascular smooth muscle cells. In the fetal membranes we
observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion,
extravillous trophoblast and decidua. There was no difference in SOD enzyme
activity or staining intensity for SOD between different cell types before
and during labour. Xanthine oxidase immunoreactivity was identified in each
of the tissues examined and again there was no difference in immunostaining
in tissues obtained from women delivered before or after the onset of
labour. These results show that the pregnant uterus is capable of both
synthesizing and degrading superoxide and suggest that superoxide dismutase
and xanthine oxidase may play a role in the maintenance of uterine
quiescence during pregnancy, but not in the initiation of parturition.
相似文献
8.
Elena I. Sklyanskaya Irina A. Rudneva Tamara S. Vovk N. V. Kaverin 《Archives of virology》1980,65(3-4):257-267
Summary In influenza virus-infected MDCK cells labelled with14C-chlorella hydrolysate or35S-methionine a virus-specific protein component is revealed migrating slightly faster than HA protein in polyacrylamide gel electrophoresis. Under chase conditions the component disappears either completely or partially, with a concomitant intensification of the HA band. The rate and extent of this transition are strain-dependent. Both the HA band and the faster moving component are not revealed if the cells are labelled in the presence of 20mM of D-glucosamine. In primary cell cultures of chick embryos a single HA band with a mobility similar to that of the faster moving component in MDCK cells has been observed. It is suggested that the transition of the label from the faster moving component to the HA band reflects the final step of HA processing specific for MDCK cells.With 7 Figures 相似文献
9.
Pre-eclampsia, one of the most significant health problems inhuman pregnancy, complicates 6-7% of all gestations and is theleading cause of fetal growth retardation, infant morbidityand mortality, premature birth and maternal death. Recent researchimplicates free radicals in the pathophysiology of pre-eclampsia.This review covers the biochemistry of nitric oxide (NO) andpossible interactions with other free radicals. Studies in therat show that pregnancy is associated with enhanced productionand responsiveness to NO in both reproductive tissues and bloodvessels. Rats infused with NG-nitro-L-arginine methyl ester(L-NAME, a NO synthase inhibitor) have been used as an animalmodel of pre-eclampsia, and the effects of steroid hormoneson blood pressure in this model have been tested. Results suggestthat pre-eclampsia may be a state of NO deficiency. However,in humans there seem to be contradictions regarding the involvementof NO in maternal adaptation to pregnancy. It is suggested thatNO may be one of several systems that act in concert to maintaina symbiotic relationship between mother and fetus. However,the input of each system may be genetically determined. 相似文献
10.
Kaverin NV Matrosovich MN Gambaryan AS Rudneva IA Shilov AA Varich NL Makarova NV Kropotkina EA Sinitsin BV 《Virus research》2000,66(2):123-129
In our previous studies influenza A virus reassortants having neuraminidase (NA) gene of A/USSR/90/77 (H1N1) strain and hemagglutinin (HA) genes of H3, H4 and H13 subtypes were shown to produce a low virus yield and to exhibit a strong tendency to virion aggregation. More detailed studies with the use of a H3N1 reassortant and its high-yield non-aggregating variants revealed that NA of A/USSR/90/77 strain is inefficient in the removal of the terminal sialic acid residues from the virion components, and that the inefficiency of NA may be compensated by mutations in HA gene leading to a decrease of the receptor-binding affinity (Kaverin, N.V. , Gambaryan, A.S., Bovin, N.V., Rudneva, I.A., Shilov, A.A., Khodova, O.M., Varich, N.L., Sinitsin, B.V., Makarova, N.L., Kaverin, N.V., 1998. Postreassortment changes in influenza virus hemagglutinin restoring HA-NA functional match, Virology 244, 315-321). The present report describes studies performed with the use of H2N1 and H4N1 reassortants having HA genes of A/Pintail/Primorie/695/76 (H2N3) and A/Duck/Czechoslovakia/56 (H4N6) strains respectively and NA gene of A/USSR/90/77 strain. The low-yield reassortants and their high-yield non-aggregating variants were studied in both direct and competitive binding assays with sialic acid-containing substrates. The non-aggregating variants were shown to have a decreased affinity as compared to the initial reassortants toward high-molecular-weight sialic acid-containing substrates. The sequencing of HA genes revealed that all non-aggregating variants of H2N1 and H4N1 reassortants had amino acid substitutions increasing the negative charge of the HA molecule in the vicinity of the receptor-binding pocket. The results suggest that the influenza virus reassortants containing low-functional NA undergo similar postreassortment changes irrespective of the HA subtype: their receptor-binding activity decreased due to negatively charged amino acid substitutions in the vicinity of the receptor-binding pocket. 相似文献