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981.
Robin Thomas Ernest Snape Annette Cameron Broderick Burak Ali Çiçek Wayne John Fuller Nicholas Tregenza Matthew John Witt Brendan John Godley 《Human ecology: an interdisciplinary journal》2018,46(3):423-433
Fisheries depredation by marine mammals is an economic concern worldwide. We combined questionnaires, acoustic monitoring, and participatory experiments to investigate the occurrence of bottlenose dolphins in the fisheries of Northern Cyprus, and the extent of their conflict with set-nets, an economically important metier of Mediterranean fisheries. Dolphins were present in fishing grounds throughout the year and were detected at 28% of sets. Net damage was on average six times greater where dolphins were present, was correlated with dolphin presence, and the associated costs were considerable. An acoustic deterrent pinger was tested, but had no significant effect although more powerful pingers could have greater impact. However, our findings indicate that effective management of fish stocks is urgently required to address the overexploitation that is likely driving depredation behaviour in dolphins, that in turn leads to net damage and the associated costs to the fisheries. 相似文献
982.
Whasun Lim Jiyeon Ham Fuller W. Bazer Gwonhwa Song 《Journal of cellular physiology》2019,234(2):1803-1815
Carvacrol is a monoterpenoid phenol present in the oils of various plants including Origanum vulgare (oregano) or Origanum majorana (marjoram). For a long time, it has been used as spice in foods because of its antimicrobial properties. Additionally, it appears to have anticancer effects against some cancer but this has not been well studied. Therefore, we conducted various assays to confirm the effects of carvacrol on choriocarcinoma cell lines (JAR and JEG3). Our results indicate that carvacrol has antiproliferative properties and induces apoptosis, resulting in increased expression of proapoptotic proteins. Additionally, carvacrol disrupted the mitochondrial membrane potential and induced calcium ion overload in the mitochondrial matrix in both JAR and JEG3 cells. Furthermore, carvacrol generated oxidative stress and lipid peroxidation in both JAR and JEG3 cells. Moreover, carvacrol-suppressed phosphoinositide 3-kinase–protein kinase B and extracellular signal–regulated kinase 1/2 mitogen-activated protein kinase (MAPK) signal transduction whereas expression of phosphor-P38 and c-Jun N-terminal kinase MAPK was increased. Together, our results indicate that carvacrol may be a possible new therapeutic agent or supplement for the control of human choriocarcinomas. 相似文献
983.
984.
Cholesterol and cholesterol esters were measured on day 90 in the plasma and aortas of rats treated on day 4 as follows: control, gonadectomy, testosterone propionate (TP), estradiol-17beta (E). Sex differences were observed in sterol concentrations of control animals but were abolished by castration. TP and E significantly altered sex gland weights, aorta cholesterol and plasma cholesterol esters of both sexes. Little effect on plasma cholesterol or esterified cholesterol of the aorta was noted in any treatment group. A dose effect of E was observed in organ weights and sterols of male rats. 相似文献
985.
The current study reinvestigated whether pure plasminolytic fragments D and E from fibrin directly increase fibrinogen synthesized by the hepatocyte. Fibrinogen protein levels and fibrinogen mRNA levels in an interleukin-6 (IL-6) responsive rat hepatoma cell line (FAZA) were measured quantitatively by [35S]-methionine pulse-chase experiments and Northern hybridizations, respectively. The results demonstrate that neither fragments D nor E, alone or in combination, in the presence or absence of dexamethasone, had any influence on the production of fibrinogen. 相似文献
986.
FERNANDO STEELE DA CRUZ STUART M. KRASSNER 《The Journal of eukaryotic microbiology》1971,18(4):718-722
SYNOPSIS. Continuous growth of one cell line (UCI variant) of Leishmania tarentolae was achieved in the absence of organic sulfur. These cells were able to use sodium sulfate, and, to a limited extent, sodium sulfite as their sole sulfur source and could utilize methionine sulfoxide in place of L-methionine. A related cell line (RU variant) was unable to grow in organic sulfate-free media nor could these cells utilize methionine sulfoxide. UCI promastigotes incorporated significant amounts of 35S sodium sulfate; killed cells did not take up the label. 35S incorporation was inhibited by sodium molybdate (5 × 10?4 M), sodium arsenite (5 × 10?4 M), 2,4-dinitrophenol (1 × 10?4 M), or KCN (5 × 10?4 M). RU promastigotes did not incorporate significant amounts of 35S sodium sulfate. Thin layer chromatographs of protein hydrolysates from UCI cells incubated in 35S sodium sulfate revealed several radio opaque spots, one of which had chromatographic properties of cystine. UCI variants of L. tarentolae were therefore capable of assimilatory sulfate reduction whereas RU cells lacked this ability. 相似文献
987.
Dopamine concentration in rat heart is normally very low, only a few percent of the concentration of norepinephrine. After treatment of rats with a dopamine beta-hydroxylase inhibitor, 1-cyclohexyl-2-mercapto-imidazole (CHMI), there was a rapid increase in dopamine concentration even before norepinephrine concentration had decreased perceptibility. This accumulation of dopamine was readily measured by liquid chromatography with electrochemical detection. Since the percentage change in dopamine was much greater than the percentage change in norepinephrine, especially at early times, measurement of dopamine accumulation rather than norepinephrine decline was considered as a useful measure of norepinephrine turnover. Drugs that act on noradrenergic receptors and are known to alter norepinephrine turnover were found to alter the rate of dopamine accumulation. Clonidine and guanabenz decreased dopamine accumulation after CHMI, whereas piperoxan (but not prazosin) increased dopamine accumulation after CHMI. Pergolide, a dopamine agonist whose lowering of blood pressure and cardiac rate has been suggested to be due to suppression of neurogenic release or norepinephrine, also decreased dopamine accumulation after CHMI. The results suggest that measuring dopamine accumulation may have advantages over measuring norepinephrine disappearance after dopamine beta-hydroxylase inhibition as an indicator of norepinephrine turnover in heart. 相似文献
988.
989.