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1.
This review discusses studies on marine macroalgae that have been investigated for their potential as sources of novel anti-cancer drugs. The review highlights the very large number of studies of crude, partially purified and purified seaweed extracts, collected from many locations, which have shown potential as sources of potent anti-cancer drugs when tested in vitro and/or in vivo. The activity of polysaccharides, polyphenols, proteinaceous molecules, carotenoids, alkaloids, terpenes and others is described here. In some reports, mechanistic studies have identified specific inhibitory activity on a number of key cellular processes including apoptosis pathways, telomerase and tumour angiogenesis. However, despite the potential shown by these studies, translation to clinically useful preparations is almost non-existent. It is hoped this review will serve as a source document and guide for those carrying out research into the potential use of macroalgae as a source of novel anti-cancer agents.  相似文献   
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The cDNA sequences for Cu,Zn superoxide dismutase from two Cervus elaphus subspecies, North American wapiti and European red deer, were determined. The derived amino acid sequences showed two differences: residue 8 was Leu in wapiti and Met in red deer and residue 25 was His in wapiti and Asn in red deer. The extra positive charge at position 25 in the wapiti isoform accounted for its greater mobility towards the cathode during non-denaturing electrophoresis, a procedure widely used in the genetic analysis of deer. There was no difference in specific activity between the two Cu,Zn superoxide dismutase isoforms, but the wapiti isoform was slightly more susceptible to heat denaturation.  相似文献   
3.
Most advocates of biogenetic modification hope to amplify existing human traits in humans in order to increase the value of such traits as intelligence and resistance to disease. These advocates defend such enhancements as beneficial for the affected parties. By contrast, some commentators recommend certain biogenetic modifications to serve social goals. As Ingmar Persson and Julian Savulescu see things, human moral psychology is deficient relative to the most important risks facing humanity as a whole, including the prospect of Ultimate Harm, the point at which worthwhile life is forever impossible on the planet. These risks can be mitigated, they say, by enhancing moral psychology in novel ways. Persson and Savulescu argue that some parents should modify the underlying biogenetics of their children's moral psychology, if such measures were safe and effective, but they admit these interventions may not decouple humanity from Ultimate Harm. Neither are these modifications the only options, they concede, for addressing risks to humanity. Even with these concessions, saving humanity from itself is a fairly poor reason to modify the moral psychology of children. In most ways, adults would be better candidates, morally speaking, for modifications of psychology. Even then, there is no direct link between morally enhanced human beings and the hoped‐for effect of better protection from Ultimate Harm. Asserting a general duty of all to contribute to the avoidance of Ultimate Harm is a better moral strategy than intervening in the moral psychology of some, even though meeting that duty may involve substantial interference with the free exercise of one's interests.  相似文献   
4.
We have developed a relatively simple simultaneous saccharification and fermentation (SSF) technique to determine the ethanol production potential for large sets of biomass samples. The technique is based on soaking approximately 0.5 grams of a biomass sample in aqueous ammonia at room temperature and at atmospheric pressure for 24 h, then fermenting with Saccharomyces cerevisiae D5A for 24 h using Spezyme CP, for enzymatic hydrolysis of structural polysaccharides. We have tested the technique on a set of corn stover samples representing much of the genetic variability in the commercial corn hybrid population. The samples were weighed into modified Ankom filter bags (F57) before soaking to avoid biomass loss during the process. Fermentation samples were analyzed for ethanol after 24 h by HPLC. Percentages of theoretical maximum ethanol yields of the samples ranged between 44.9 and 73%. We observed that percentages of theoretical maximum ethanol yields were highly correlated (r 2?=?0.90) with acid detergent lignin concentration while a low correlation was observed between cellulose concentration and ethanol yield. Near infrared spectra of corn stover samples were also examined. The coefficient of determination (r 2) from regression of predicted versus measured percent theoretical maximum ethanol yield was 0.96. This result suggests that using NIRS is a promising method for predicting ethanol yield, but larger calibration sets are necessary for obtaining improved accuracy for larger sample populations. We conclude that the developed SSF technique could be applied to large numbers of biomass samples to rapidly estimate ethanol yields and to compare different biomass samples in terms of ethanol yields.  相似文献   
5.
Over the past 5 years, massive accumulations of holopelagic species of the brown macroalga Sargassum in coastal areas of the Caribbean have created “golden tides” that threaten local biodiversity and trigger economic losses associated with beach deterioration and impact on fisheries and tourism. In 2015, the first report identifying the cause of these extreme events implicated a rare form of the holopelagic species Sargassum natans (form VIII). However, since the first mention of S. natans VIII in the 1930s, based solely on morphological characters, no molecular data have confirmed this identification. We generated full‐length mitogenomes and partial chloroplast genomes of all representative holopelagic Sargassum species, S. fluitans III and S. natans I alongside the putatively rare S. natans VIII, to demonstrate small but consistent differences between S. natans I and VIII (7 bp differences out of the 34,727). Our comparative analyses also revealed that both S. natans I and S. natans VIII share a very close phylogenetic relationship with S. fluitans III (94‐ and 96‐bp differences of 34,727). We designed novel primers that amplified regions of the cox2 and cox3 marker genes with consistent polymorphic sites that enabled differentiation between the two S. natans forms (I and VIII) from each other and both from S. fluitans III in over 150 Sargassum samples including those from the 2014 golden tide event. Despite remarkable gene synteny and sequence conservation, the three Sargassum forms differ in morphology, ecology, and distribution patterns, warranting more extensive interrogation of holopelagic Sargassum genomes as a whole.  相似文献   
6.
Summary The ability of suspension-cultured rose (Rosa damascena Mill. cv Gloire de Guilan) cells to reduce ferricyanide is decreased by 50% during an overnight incubation in a low-nutrient (1 mM CaCl2, 0.1 mM KCl) solution. This loss is not observed when nitrate and/or glutamate is added to the low-nutrient medium, but it occurs in medium containing all the components needed for normal growth except nitrate plus glutamate. Thus, the cells possess both constitutive and inducible enzymes for the reduction of ferricyanide, and nitrate or glutamate is both necessary and sufficient to stimulate the production of the inducible enzyme.  相似文献   
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Reversible denaturation of C-phycocyanin   总被引:1,自引:0,他引:1  
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TICK PARALYSIS     
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