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61.
Ciguatera Fish Poisoning (CFP) is the most frequently reported seafood-toxin illness in the world, and it causes substantial physical and functional impact. It produces a myriad of gastrointestinal, neurologic and/or cardiovascular symptoms which last days to weeks, or even months. Although there are reports of symptom amelioration with some interventions (e.g. IV mannitol), the appropriate treatment for CFP remains unclear to many physicians. We review the literature on the treatments for CFP, including randomized controlled studies and anecdotal reports. The article is intended to clarify treatment options, and provide information about management and prevention of CFP, for emergency room physicians, poison control information providers, other health care providers, and patients.  相似文献   
62.
Due to the tonic and nutritive virtues of sea cucumbers, increased commercial aquaculture has resulted in the expansion of breeding ponds, a primary form of sea cucumber production. Expansion of such production methods has led to increased settling of organic wastes onto the seabed, resulting in enriched sediments. Nitzschia sp. serves as an edible sea cucumber feed. Release characteristics of nitrogen (N) and phosphorus (P) from sediments in the presence of different biomass densities of Nitzschia sp. were studied via laboratory static cultures. pH and dissolved oxygen (DO) in the overlying water and biochemical components (i.e., protein, chlorophyll a) of Nitzschia sp. were assessed. When the biomass of Nitzschia sp. was more than (2–5) × 104 ind/cm2, the release of N and P nutrients was significantly promoted; additionally, the DO content of the overlying water was relatively high and the pH was relatively stable, which favoured the accumulation of proteins and chlorophyll a in Nitzschia sp. The results indicated that Nitzschia sp. promotes the release of N and P in sediments while absorbing them to maintain their own growth and promote the accumulation of nutrients, such as proteins, for the sea cucumbers. At the same time, the algae release oxygen, increasing the DO of the overlying water, providing a healthy breeding environment for the sea cucumbers. Application of Nitzschia sp. has the potential to reduce environmental harm caused by sea cucumber cultivation and thus achieve sustainable aquaculture.  相似文献   
63.
硅藻在海洋中分布广泛,适应于多种生长环境。本文对海洋硅藻应对低铁胁迫的策略进行综述,以期为研究海洋藻类在低铁环境下的生理代谢状态提供参考。  相似文献   
64.
开花期红掌耐寒性评判方法研究   总被引:2,自引:0,他引:2  
【目的】探究开花期红掌(Anthurium andraeanum)耐寒性判定方法,为不同耐寒性红掌品种的分级管理提供理论依据。【方法】以20个开花期红掌品种为试材,在上海地区冬季大棚自然低温环境下进行种植,观察叶柄、叶片、花柄、苞片的冷害症状,统计各器官冷害指数,通过主成分和聚类分析进行耐寒性研究;根据聚类结果分别在不同耐寒性组中选择1~3个品种再次进行低温试验,并测定低温处理前后叶片的叶绿素荧光参数F_v/F_m、相对电导率和丙二醛、可溶性蛋白、可溶性糖含量以及过氧化物酶、超氧化物歧化酶活性,进行各指标变化率与耐寒性的相关性分析。【结果】对供试红掌品种各器官冷害指数进行主成分分析,得到20个品种的耐寒性综合得分,结合聚类分析结果将其分为3组,高耐寒组品种包括‘阿拉巴马’、‘艾美拉’、‘粉阿拉巴马’、‘黑皇后’、‘红宝贝’、‘马都拉’、‘潘多拉’、‘紫罗兰’、‘红丰收’、‘红成功’、‘红赢家’、‘白塞拉’、‘紫雷鸟’和‘特伦萨’,中耐寒组品种包括‘皇家布加迪’、‘轰动’、‘红阿里克斯’和‘白雪阿莱西亚’,低耐寒组品种有‘粉冠军’和‘粉爱’,其中‘阿拉巴马’、‘潘多拉’、‘特伦萨’、‘皇家布加迪’、‘轰动’和‘粉冠军’6个品种的耐寒性得到了再次验证。相关性分析结果表明,红掌在低温处理前后叶绿素荧光参数F_v/F_m的变化率与耐寒性显著正相关,相对电导率变化率与耐寒性极显著负相关,其他指标与耐寒性则没有表现出显著相关性。【结论】自然低温下器官冷害指数的观测可以作为判定开花期红掌耐寒性的一种有效方法,而叶绿素荧光参数F_v/F_m和相对电导率可以作为较为可靠的生理指标应用于红掌耐寒性的分析中。  相似文献   
65.
Climate change has led to major shifts in the timing of biological events, with many studies demonstrating earlier phenology in response to warming. However, few of these studies have investigated the effects of climate change on the phenology of larvae in marine species. Phenological shifts can result in mismatches between consumers and prey and hence affect growth and survival of individuals, and ultimately population demography. We investigated the temporal changes in phenology and abundance of the larvae of dominant brachyuran crabs in the southern Gulf of St. Lawrence (eastern Canada) based on plankton collections spanning 1982–2012. The Gulf of St. Lawrence has warmed since the early 1990s, and our analyses revealed that larvae of snow crab (Chionoecetes opilio) and toad crabs (Hyas spp.) exhibited a significant trend towards earlier phenology over the 30‐year study period. This shift in phenology appeared to be a consequence of the effect of climate warming on both the timing of hatching and larval development rate. Larval abundance responded differently by crab taxon to climate warming, likely due to differences in thermal tolerance. The warming trend was unfavourable to snow crab, which is the most cold‐adapted and stenothermic of the taxa examined in this study. The abundance of snow crab larvae was lower when sea ice retreat occurred earlier than day 110 of the year and sea surface temperature was higher than 8.5°C. On the other hand, larval abundance of rock crab (Cancer irroratus), which prefers higher temperatures, was positively related to surface temperature.  相似文献   
66.
随着全球气候变化和水体富营养化程度加剧,蓝藻水华已经成为一个世界性的环境问题。它不但对水生生态系统有许多负面影响,还会严重威胁人类的公共卫生安全。目前,蓝藻水华的治理技术主要包括物理法、化学法和生物法等。近年来,溶藻细菌作为一种新型蓝藻水华生物防治方法,由于其环境友好、作用特异受到广泛关注。目前,已经发现了很多溶藻菌,并开展了溶藻物质鉴定和溶藻作用机制研究。本文根据近十年来发表的文献,对溶藻细菌种类、溶藻物质作用机理的研究现状进行了归纳、总结,并对未来进一步研究和应用溶藻菌控制蓝藻水华的进行了展望。  相似文献   
67.
调查了南太湖水体蓝藻爆发前后底栖动物的种类及数量。2008年在南太湖中共采集到底栖动物11科、21种(属)。底栖动物平均密度为768个/m2,平均生物量为248.783g/m2。第一优势种群为软体动物的河蚬,其次为环节动物寡毛纲的霍甫水丝蚓。结果显示,在蓝藻爆发高峰期底栖动物的密度和生物量明显降低。  相似文献   
68.
用统计分析方法,从构件水平研究了盛花期一年蓬种群各构件生物量结构特征、一些构件生物量之间的关系模型和各构件生物量与其他所测相关指标的关系模型,并进行定量分析。结果表明,一年蓬各构件生物量之间关系为茎>花序>叶>根。各构件生物量在个体生物量中所占的比率表现同样的关系。一年蓬花构件生物量与茎构件生物量之间显著地呈线性正相关,一年蓬比叶面积变异系数在各构件生物量变异系数中最小(24.45%)。一年蓬各构件生物量与其他所测指标在非线性模型中表现显著正相关。  相似文献   
69.
鱼腥藻研究进展   总被引:1,自引:0,他引:1  
鱼腥藻是一种蓝藻门念珠藻类微藻,既能进行光合作用也能进行固氯作用.笔者分别论述了近年来在鱼腥藻的培养、水华鱼腥藻及其治理、鱼腥藻藻蓝蛋白的获得以及转基因鱼腥藻的研究进展.  相似文献   
70.
M1增产素对小麦抗旱增产生理效应初报   总被引:3,自引:0,他引:3  
通过M1增产素(有机酸类物质与植物激素配伍)对小麦进行浸种和开花期叶面喷洒试验,结果表明浸种能促进根系和地上部生长,能提高小麦的抗旱能力,花期喷洒能防止叶片早衰,有明显的保绿作用,促进结实,浸种并配合花期喷洒,则有更加明显的增产效果。  相似文献   
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