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1.
Headspace analysis combined with high-resolution gas chromatography and detection by mass spectrometry was evaluated for the analysis of 53 volatile organic compounds (VOCs) in river waters, waste waters and treated water samples down to 0.1 microgl(-1) concentration levels. The conditions optimised included sample thermostatting time and temperature, autosampler parameters and the nature of salt, added to the sample. The pollutions origin and their seasonal rippling have been done. It was shown that the content of VOCs in river water mainly correlates to the content of these compounds in waste waters, which shows the anthropogenic character of the pollutions.  相似文献   
2.
The Miocene terrestrial plant assemblage (in macro- and microfossils) from the underwater Yamato Rise (Sea of Japan) is examined. A fossil leaf found in the tuffogenic–sedimentary strata is identified as belonging to the beech tree. Data on the Paleogene–Neogene history of the underwater rise are given. Against the background of its general subsidence, positive relief features (volcanoes and their formations) were formed. During the Cenozoic, the entire Sea of Japan depression experienced a submergence.  相似文献   
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Compounds containing nitrogen and sulfur atoms can be widely used in various fields such as industry, medicine, biotechnology and chemical technology. Therefore, the reactions of aminomethylation and alkoxymethylation of mercaptobenzothiazole, mercaptobenzoxazole and 2-aminothiazole were developed. Additionally, the alkoxymethyl derivatives of mercaptobenzoxazole and 2-aminothiazole were synthesized by a reaction with hemiformals, which are prepared by the reaction of alcohols and formaldehyde. In this study, the inhibitory effects of these molecules were investigated against acetylcholinesterase (AChE), butyrylcholinesterase (BChE) enzymes and carbonic anhydrase I, and II isoenzymes (hCA I and II). Both hCA isoenzymes were significantly inhibited by the recently synthesized molecules, with Ki values in the range of 58–157?nM for hCA I, and 81–215?nM for hCA II. Additionally, the Ki parameters of these molecules for BChE and AChE were calculated in the ranges 23–88 and 18–78?nM, respectively.  相似文献   
5.
The practical use of the reverse passive hemagglutination test for the examination of viral hepatitis patients revealed the presence of HBsAg, on the average, in 28.4 +/- 0.95% of cases. This antigen occurred most frequently among the patients aged up to 1 year (42.8 +/- 4.18%), as well as in the second quarter of the year (33.3 +/- 2.3%). The proportion of patients with hepatitis B in the total number of patients with viral hepatitis was 20%.  相似文献   
6.
Nazina  T. N.  Abukova  L. A.  Tourova  T. P.  Babich  T. L.  Bidzhieva  S. Kh.  Filippova  D. S.  Safarova  E. A. 《Microbiology》2021,90(5):621-631
Microbiology - Underground natural gas storage facilities (UGS) have been recently proposed as sites to store “green” gas containing biogas, synthetic methane, and molecular hydrogen....  相似文献   
7.
Total ion (Na+, K+, Ca2+, SO4 2? and Cl?) accumulation by plants, ion contents in plant tissues and ion secretion by salt glands on the surface of shoots of Tamarix ramosissima adapted to different soil salinity, namely low (0.06 mmol Na+/g soil), moderate (3.14–4.85 mmol Na+/g soil) and strong (7.56 mmol Na+/g soil) were analyzed. There are two stages of interrelated and complementary regulation of ion homeostasis in whole T. ramosissima plants: (1) regulation of ion influx into the plant from the soil and (2) changing the secretion efficiency of salt glands on shoots. The secretion efficiency of salt glands was appraised by the ratio of ion secretion to tissue ion content. Independent of soil salinity, the accumulation of K+ and Ca2+ was higher than the contents of these ions in the soil. Furthermore, the accumulation of K+, Ca2+ and SO4 2? ions by plants was maintained within a narrow range of values. Under low soil salinity, Na+ was accumulated, whereas under moderate and strong salinity, the influxes of Na+ were limited. However, under strong salinity, the accumulation of Na+ was threefold higher than that under low soil salinity. This led to a change in the Na+/K+ ratio (tenfold), an increase in the activity of salt glands (tenfold) and a reduction in plant growth (fivefold). An apparently high Na+/K+ ratio was the main factor determining over-active functioning of salt glands under strong salinity. Principal component analysis showed that K+ ions played a key role in ion homeostasis at all levels of salinity. Ca2+ played a significant role at low salinity, whereas Cl? and interrelated regulatory components (K+ and proline) played a role under strong salinity. Proline, despite its low concentration under strong salinity, was involved in the regulation of secretion by salt glands. Different stages and mechanisms of ion homeostasis were dominant in T. ramosissima plants adapted to different levels of salinity. These mechanisms facilitated the accumulation of Na+ in plants under low soil salinity, the limitation of Na+ under moderate salinity and the over-activation of Na+ secretion by salt glands under strong salinity, which are all necessary for maintaining ion homeostasis and water potential in the whole plant.  相似文献   
8.
The study of the dynamics of specific antibody formation in response to immunization against typhoid fever with adsorbed chemical vaccine T in its relationship to the phenotype of acetylation has yielded results characterizing a considerable variability of immune response simultaneously with the definite type of modification of parameter A.  相似文献   
9.
Cyclooxygenases are key enzymes in the arachidonic acid metabolism. Their unstable intermediate, prostaglandin H2, is further metabolized to bioactive lipids by various downstream enzymes. In this study, utilizing short hairpin RNAs, we prepared a cell line of human cervix carcinoma with stable down-regulated cyclooxygenase-1 (COX-1) to assess the impact of COX-1 reduction on the downstream enzymes. We found a significant microsomal prostaglandin E synthase-1 (mPGES-1) suppression. In addition, mRNA expression of multidrug resistance protein 4 (MRP4, ABCC4), supposed to take part in antiviral and anticancer drug transport from cells, was up-regulated after COX-1 down-regulation. Our findings indicate that mPGES-1, believed to be coexpressed preferentially with cyclooxygenase-2, may be coupled to COX-1. ABCC4 up-regulation further supports the assumption of its involvement in prostanoid transport.  相似文献   
10.
Many drugs are cardiotoxic because they inhibit hERG K+ channels, thus prolonging the repolarization phase of the cardiomyocyte action potential giving rise to cardiac arrhythmias. Early detection of inhibiting effects of candidate drugs on the activity of K+ channels in cardiomyocytes is one of the main challenges in preclinical drug screening. The aim of this study was to obtain a cell line expressing recombinant hERG channels at a stable and reproducible level as a prerequisite to its further application as a test system.  相似文献   
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