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951.
J S Stoff P Silva M Field J Forrest A Stevens F H Epstein 《The Journal of experimental zoology》1977,199(3):443-448
Active transport of chloride in the salt secreting rectal gland of the dogfish Squalus acanthias is markedly stimulated by the addition of theophylline (0.01 to 5 mM) or dibutyryl cyclic AMP (0.05 mM) during in vitro perfusion. The effect occurs promptly and may persist for two hours. Specific hormonal effectors have not yet been identified. The isolated perfused rectal gland thus offers a unique opportunity to examine the cellular mechanisms of active chloride secretion. 相似文献
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The accumulation of biofouling on coastal structures can lead to operational impacts and may harbour problematic organisms, including non-indigenous species. Benthic predators and grazers that can supress biofouling, and which are able to be artificially enhanced, have potential value as augmentative biocontrol agents. The ability of New Zealand native invertebrates to control biofouling on marina pontoons and wharf piles was tested. Caging experiments evaluated the ability of biocontrol to mitigate established biofouling, and to prevent fouling accumulation on defouled surfaces. On pontoons, the gastropods Haliotis iris and Cookia sulcata reduced established biofouling cover by >55% and largely prevented the accumulation of new biofouling over three months. On wharf piles C. sulcata removed 65% of biofouling biomass and reduced its cover by 73%. C. sulcata also had better retention and survival rates than other agents. Augmentative biocontrol has the potential to be an effective method to mitigate biofouling on marine structures. 相似文献
957.
Yi Wang David E. Berthold Jing Hu Forrest W. Lefler I-Shuo Huang H. Dail Laughinghouse IV 《Journal of phycology》2023,59(6):1147-1165
Benthic cyanobacterial mats (BCMs) are natural phenomena in marine environments. Reports of BCMs occurring across coastal marine environments have increased, partly driven by nutrient loading and climate change; thus, there is a need to understand the diversity involved in the proliferations and potential toxicity of the BCMs. Furthermore, marine cyanobacterial mats are observed growing on and affecting the health of corals with one specific cyanobacterial genus, Roseofilum, dominating the microbial mats associated with black band disease (BBD), a destructive polymicrobial disease that affects corals. To explore the diversity of Roseofilum, cyanobacterial mats from various marine habitats were sampled, and individual isolates were identified based on morphology, 16S rRNA gene phylogenies, 16S–23S ITS rRNA region sequence dissimilarities, and phylogenomics. Four novel species of Roseofilum were isolated from benthic marine mats, three from the coasts of Florida, United States (R. capinflatum sp. nov., R. casamattae sp. nov., and R. acuticapitatum sp. nov.) and one from the coast of France (R. halophilum sp. nov.). Our analyses revealed that Roseofilum associated with coral BBD and those not associated with corals but rather from coastal benthic mats are systematically distinct based on both phylogenetic and phylogenomic analyses. Enzyme-linked immunosorbent assay (ELISA) and LC–MS data indicated that microcystin production was found in one of the four species. 相似文献
958.
Steroid metabolism by human breast tumours. 总被引:1,自引:0,他引:1
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960.
D Cunningham N L Gilchrist R A Cowan G J Forrest C S McArdle M Soukop 《BMJ (Clinical research ed.)》1985,291(6503):1153-1155
Ten patients with low grade non-Hodgkin''s lymphoma (seven follicular small cleaved and three small lymphocytic) were treated with 1 microgram oral alfacalcidol (1 alpha-hydroxycholecalciferol) daily. Of the seven patients with lymphomas of follicular small cleaved subtype, one achieved complete and three partial remission, whereas none of three patients with small lymphocytic lymphomas responded. In seven of the 10 patients, 1,25(OH)2D3 receptors were measured in tissue from lymph nodes, and a positive correlation between the presence and amount of receptor and response to alfacalcidol was found. These preliminary data suggest that alfacalcidol has appreciable antitumour activity in low grade non-Hodgkin''s lymphomas. 相似文献