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141.
The influence of taurine (in drinking water for 6 weeks) on PGI2 and TXA2 synthesis by some female rat organs was investigated using radioimmunoassay and platelet antiaggregatory bioassay. Taurine 100 and 200 mg/kg/day increased aortic PGI2 release from 0.59 ± 0.04 (control) to 0.85 ± 0.05 and 1.01 ± 0.06 ng/mg, respectively and that by the myometrium from 0.24 ± 0.02 (control) to 0.38 ± 0.01 and 0.50 ± 0.04 ng/mg wet tissue, respectively (P < 0.05, n = 6). It did not affect PGI2 and TXA2 production in the heart or TXA2 in the aorta. Taurine 200 mg/kg depressed uterine TXA2 synthesis from 148.6 ± 9.8 (control) to 85.4 ± 6.8 pg/mg (P < 0.05, n = 6). Furthermore taurine 0.4 and 0.8 mM in vitro stimulated PGI2 released by the myometrial and aortic tissues from pregnant rats. The stimulant effect of taurine on PGI2 may be related to its antioxidant effect whereas its inhibitory effect on uterine TXA2 may result from direction of synthesis towards PGI2. It is concluded that endogenous taurine may participate in regulation of PGs synthesis and that prostanoids may contribute to its known actions. On broad basis, taurine-induced release of PGI2 may prove of potential value in those ailments characterised by deficiency in PGI2 release. 相似文献
142.
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145.
P Goliński S Wnuk J Che?kowski A Visconti M Schollenberger 《Applied and environmental microbiology》1986,51(4):743-745
A compound very similar to the mycotoxin citrinin was observed on thin-layer chromatographic plates during the screening analysis of grain extracts. This compound was produced by 22 of the tested Fusarium avenaceum (Corda ex Fries) Sacc. strains isolated from wheat, triticale, barley, corn, and potatoes. A chemical test confirmed the presence of an unknown compound, which was given the preliminary name of antibiotic Y (indicating yellow fluorescence). The following properties of the new metabolite are described: spectroscopic (UV, infrared, proton nuclear magnetic resonance, fluorescence, and mass spectrometry), phytotoxic, antibiotic (inhibitory effect of bacterial growth), and toxic (toxicity to Artemia salina, chicken embryos, and mouse fibroblasts). Elemental analysis of the compound showed that it had the general formula C15H10O8, in agreement with the mass spectrometric finding that the molecular ion had a molecular weight of 318. The structure of the compound is presently under study. 相似文献
146.
A fluorometric methods is described for determination of cardiac and urinary 3-methoxytyramine, a metabolite of dopamine. Methoxy metabolites were isolated on Amberlite CG-50 resin and oxidation to emitter form was performed with K3Fe(CN)6. Good specificity and sensitivity of determination, and a high recovery of 3-MT were obtained. 相似文献
147.
K. Gwoździński 《Radiation and environmental biophysics》1986,25(2):107-111
Summary The paper presents some results on the effect of PCMB and NEM on the transport of non-electrolyte spin labels: TEMPO and TEMPOL across non-irradiated and irradiated porcine erythrocyte. Irradiated erythrocytes exhibited increased inhibitory effect of thiol reactive compounds in the TEMPO and TEMPOL transport compared to non-irradiated erythrocytes. 相似文献
148.
A. Wiercińska 《International Journal of Anthropology》1986,1(3):277-280
The traditional cranioscopic traits possess undoubted taxonomic value in interpreting interpopulational relationships. However,
there is a lack of studies on the correlations between particular traits. In order to fill this gap, the following set of
4 traits was analysed by use of the multiple stachastic correlations method of Wanke: 1. prominence of maxilla, 2. lower margin
of nasal aperture, 3. depth of canine fossa and 4. depth of maxillary incisure. These traits were examined by use of the photographic
scales of Michalski within the series of 104 crania from a local population of Wislica, Poland, dated to the Early Medieval
Period. The significant associations appeared in the combinations 1–2, 1–3, 3–4, 1–2–3, 1–2–4, 1–3–4, 2–3–4 and 1–2–3–4. After
removal of all the possible interactions, still significant associations remained in 1–2–4, 2–3–4, and 1–3–4. Moreover, the
places of significant surpluses appeared in the extreme places, i.e. those characterising the Europoid and Mongoloid crania. 相似文献
149.
Abundance and biomass estimates of the benthic fauna in Admiralty Bay,King George Island,South Shetland Islands 总被引:9,自引:6,他引:3
Summary Quantitative benthic samples were collected along three transects in Admiralty Bay, King George Island, South Shetlands. At each of a total of 18 stations, between 15 and 250 m depth, we took 3 replicate samples with a van Veen grab. Animals collected were classed into major groups. Abundance and biomass per m2 was calculated for each sampling site. Considerable population densities and high biomass values were found. Most abundant groups were Bivalvia, Polychaeta and Amphipoda, whereas the largest part of the biomass was due to Ascidiacea, Ophiuroidea, Echinoidea, Polychaeta and Bivalvia. The maximum abundance recorded was 36,000 ind m-2 while the average was approximately 6500 ind m-2. Maximum biomass was over 2400 g m-2 with an average of ca. 700 g m-2. The contribution to the total biomass by groups such as the Oligochaeta, Cumacea and Tanaidacea was higher in the inner shallow part of Admiralty Bay (Ezcurra Inlet) than in the deeper areas of the bay. Our results confirm the reports on an unusually high density and biomass of the Antarctic sublittoral benthic fauna. Sessile suspension feeders belonging to the Bivalvia, Ascidiacea, sedentary Polychaeta, and vagile scavengers of the Ophiuroidea, Amphipoda and errant Polychaeta are the most significant groups in the Antarctic Ecosystem. The total benthic biomass in Admiralty Bay, based on the present preliminary quantitative data, was estimated to be over 600,000 t. This value is probably still an underestimate. 相似文献
150.
Agrobacterium radiobacter, strain B6 (a strain isolated in this laboratory, which limited the occurrence of damping-off of sugar beet and influenced growth of plants in hot-house and field experiments) was found to produce an acidic exopolysaccharide in a mineral medium with various carbon sources. Hydrolyzates of the polysaccharide contained glucose, galactose, glycerol, succinic acid and pyruvic acid, whose quantitative content varied according to the carbon source used. The polysaccharide isolated from the medium containing glucose exhibited the highest physiological activity. Seeds germinated best and sugar beet roots were found to grow most rapidly in a medium containing 0.2 % (W/W) of the polysaccharide. The roots exposed for 3 d in this medium grew 2.7-fold as compared with non-treated plants. Higher sumbers of microorganisms were detected on the surface of roots treated with the polysaccharide. Growth of roots was also stimulated when immersing the seeds (30 min) in a 0.2 –0.4 % solution of this polysaccharide. After a two-fold treatment the roots were less damaged by the fungusPythium ultimum. Plants from seeds treated with the polysaccharide grew in the field soil more rapidly than the non-treated plants but worse than after bacterization of the seeds byA. radiobacter B6 and were only partially protected against the damping-off of sugar beet. 相似文献