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151.
125I-labelled o-iodobenzoate (OIB) was prepared by means of an isotopic exchange reaction; its distribution and excretion were determined and its pharmacokinetic parameters in rats were calculated. The calculated value of the half-life of OIB elimination was 38.7 +/- 0.7 min, the distribution volume was 278.2 +/- 53.5 ml . kg-1. The rate of elimination activity in urine was in agreement with the above values. On the basis of the developed technique of separation of OIB metabolites by thin-layer chromatography, their relative proportion in rat urine was determined; within 24 h 50% of the eliminated activity was in the original form (as OIB) and the metabolites of o-iodohippurate and o-iodobenzoylglucuronide formed approximately 25% of the activity eliminated in urine each.  相似文献   
152.
Extremophiles - The aim of this study was to assess the phylogenetic relationships, ecology and ecophysiological characteristics of the dominant planktic algae in ice-covered lakes on James Ross...  相似文献   
153.
Growth requirements of 10 possibly thermophilic strains of cyanobacteria were compared under a wide spectrum of light and temperature conditions (7–80Wm?2, 12–40°C). The strains were isolated from different localities: six of thermal springs in Slovakia (4 from Pie??any, 2 from Sklené Teplice), one from thermal waters in Rupite, Bulgaria, 2 strains from a hypersaline lake Chott-el-Djerid, Tunisia, and one strain from the tropical island of Cebu, Philippines. Although the crossed gradient unit allowed only sub-optimal temperature range with respect to thermophile definition, i.e. optimum temperature above 45°C, there were difference among the strains. The most thermophilic and high-light tolerant strain was Synechococcus bigranulatus strain Lukavsky 2005/66, with a peak above 45°C; the second was Chroococcidiopsis thermalis strain Hindák 2008/9, and Isocystis sp. strain Hindák 2006/1. The temperature requirements of other strains were similar; the least thermophilic were both Slovakian strains of the genus Hapalosiphon. Growth was not limited below 80 W m?2, except for H. fontinalis strain Hindák 2008/3, which prefers lower irradiance. Hapalosiphon delicatulus strain Hindák 2007/20, isolated from a bark tree on the tropical island of Cebu was rather mesophilic than thermophilic and shade-preferring. The CCA revealed that the ecologically similar strains originated from the same or nearby localities. There were no significant correlations between temperature optima in culture and in nature. Bulgarian and Tunisian strains preferred higher irradiances.  相似文献   
154.
Biological Trace Element Research - Sera of 240 randomly selected Prague inhabitants of both sexes from ages 6 to 65 yr were analyzed by instrumental neutron activation analysis (INAA) for Fe, Zn,...  相似文献   
155.
A cell assay system was developed that allows Bacillus thuringiensis delta-endotoxins activated at high pH (10.5) to be tested in vitro without causing alkaline injury to target cells. The assay is carried out on a lawn of gel-suspended cells, requires only 1 microliter of sample per dose, and is quantitative, rapid, and sensitive. The threshold dose for toxicity of B. thuringiensis subsp. kurstaki HD-73 with IPRI-CF-1 cells was 24 pg protein. The assay is also very useful for identifying antibodies which inhibit toxicity and for detecting beta-exotoxin.  相似文献   
156.
Biological Trace Element Research - The possibility of the routine PIXE measurement of environmental samples has been tested at the INP in ?e?. Both thin samples of aerosols collected on...  相似文献   
157.
Relationships between seed protein patterns of 16 species ofArachis were studied by means of immunochemical methods (immunoelectrophoresis and double diffusion). The broad similarity of these patterns suggests that protein patterns are conservative in this genus from an evolutionary viewpoint. The differences which have evolved support recent schemes for classifying the genus, particularly the breakdown into sections. It also suggests thatA. villosa andA. correntina should probably be recognized as distinct species. The strong relationship indicated betweenA. hypogaea andA. batizocoi supports the hypothesis that the latter may be source of one of the genomes ofA. hypogaea. The possibility thatA. cardenasii might be the source of the other genome did not receive such strong positive support.  相似文献   
158.
Ambroxol has been determined in biological fluids using a rapid and sensitive high-performance liquid chromatographic method. The samples prepared from plasma by liquid—liquid extraction were analysed on reversed-phase silica gel by competing-ion chromatography with ultraviolet detection. The method was applied to the determination of ambroxol levels in twelve healthy volunteers after oral administration of 90 mg of ambroxol in tablets of Mucosolvan and Ambrosan.  相似文献   
159.
160.
Some of the epithelial cells of the rat lung take up serotonin from the circulation whereas the precursor of serotonin, 5--HTP, or histamine and histidine are not taken up. The observations raise the possibility that serotonin accumulation could be a manifestation of the general potentials of the entoderm.  相似文献   
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