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991.
  • 1. As the interest of divers in exploring marine protected areas grows, so does their impact on sensitive marine organisms and communities. This situation has led managers to adopt a variety of measures to manage scuba diving in marine reserves. However, if marine areas need to be managed and protected from the adverse effects of human activities, then the characterization of marine habitats and the communities they contain, along with the potential effects of scuba diving, will need to be evaluated on scientific lines.
  • 2. To this end, the use of benthic mapping, together with an evaluation of community vulnerability, constitutes a complementary tool for managing scuba diving, as is demonstrated in the present study.
  • 3. The identification and evaluation of the different communities observed in Cabo de Palos‐Islas Hormigas Marine Reserve enables managers to propose different measures for controlling potential diver impact and also for evaluating the effects of these measures, thus reducing the degradation of the benthic organisms and communities, benefiting the local tourism industry and allowing a more sustainable use of the marine reserve resources.
Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
992.
Potassium channel Kv1.5 has been considered a key target for new treatments of atrial tachyarrhythmias, with few side effects. Four new debromoaplysiatoxin analogues with a 6/6/12 fused ring system were isolated from marine cyanobacterium Lyngbya sp. Their planar structures were elucidated by HRESIMS, 1D and 2D NMR. The absolute configuration of oscillatoxin J (1) was determined by single-crystal X-ray diffraction, and the absolute configurations of oscillatoxin K (2), oscillatoxin L (3) and oscillatoxin M (4) were confirmed on the basis of GIAO NMR shift calculation followed by DP4 analysis. The current study confirmed the absolute configuration of the pivotal chiral positions (7S, 9S, 10S, 11R, 12S, 15S, 29R and 30R) at traditional ATXs with 6/12/6 tricyclic ring system. Compound 1, 2 and 4 exhibited blocking activities against Kv1.5 with IC50 values of 2.61 ± 0.91 µM, 3.86 ± 1.03 µM and 3.79 ± 1.01 µM, respectively. However, compound 3 exhibited a minimum effect on Kv1.5 at 10 µM. Furthermore, all of these new debromoaplysiatoxin analogs displayed no apparent activity in a brine shrimp toxicity assay.  相似文献   
993.
用表达禽流感病毒血凝素HA抗原的重组质粒pCAGGoptiHA5 100μg免疫SPF鸡,用流式细胞仪检测鸡体内CD8 T细胞的动态变化。一次免疫后,免疫组外周血中CD8 T淋巴细胞数目逐渐上升,并于第3周达到峰值,在二次免疫后,SPF鸡体内CD8 T细胞数量上升速率明显高于初免时上升速率,并于第二次免疫后2周达到一个峰值,攻毒后,二次免疫的SPF鸡外周血中CD8 T淋巴细胞数量略有上升,但上升幅度不大,2周时检测发现其下降幅度明显低于一次免疫组。而阴性对照组SPF鸡外周血中CD8 T淋巴细胞的数目则无明显变化,但在攻毒后其外周血中CD8 T淋巴细胞数量也呈上升趋势,但未达到免疫组的水平,并且在1周内全部死亡。结果表明,pCAGGopti-HA5 DNA疫苗质粒可诱导有效的细胞免疫应答。  相似文献   
994.
采用富集培养方法从氯嘧磺隆生产单位排污口处污泥中分离得到一株能降解氯嘧磺隆细菌,命名为D310-5。通过对该菌株形态特征观察,生理生化特性和16S r DNA序列分析,将菌株D310-5鉴定为肠杆菌属(Enterobacter sp.)。采用响应面分析方法探究底物浓度、温度、p H和培养时间对菌株D310-5降解氯嘧磺隆影响,优化菌株D310-5对氯嘧磺隆降解条件。结果表明,菌株D310-5最佳降解条件为底物浓度101.57 mg·L-1,温度30.25℃,p H 6.63,培养时间5 d。在最佳条件下,菌株D310-5对氯嘧磺隆降解率为87.57%。  相似文献   
995.
Xestenone is a marine norditerpenoid found in the northeastern Pacific sponge Xestospongia vanilla. The relative configuration of C-3 and C-7 in xestenone was determined by NOESY spectral analysis. However the relative configuration of C-12 and the absolute configuration of this compound were not determined. The authors have now achieved the total synthesis of xestenone using their developed one-pot synthesis of cyclopentane derivatives employing allyl phenyl sulfone and an epoxy iodide as a key step. The relative and absolute configurations of xestenone were thus successfully determined by this synthesis.  相似文献   
996.
Every year, hundreds of new compounds are discovered from the metabolites of marine organisms. Finding new and useful compounds is one of the crucial drivers for this field of research. Here we describe the statistics of bioactive compounds discovered from marine organisms from 1985 to 2012. This work is based on our database, which contains information on more than 15,000 chemical substances including 4196 bioactive marine natural products. We performed a comprehensive statistical analysis to understand the characteristics of the novel bioactive compounds and detail temporal trends, chemical structures, species distribution, and research progress. We hope this meta-analysis will provide useful information for research into the bioactivity of marine natural products and drug development.  相似文献   
997.
试验选择从添加磷矿粉的高温堆肥样品中筛选出1株耐高温无机磷降解菌,以培养温度、培养时间、磷矿粉添加量和菌剂接种量为主要因素,采用L16(45)正交试验设计,对不同参数条件下解磷菌的解磷能力进行了研究。结果表明,培养时间对无机磷降解菌的解磷量及解磷率的影响最为显著,在培养基中磷矿粉添加量、菌剂接种量分别为7.0g·L-1和5mL·L-1,在45℃下培养22d后,发酵液中解磷总量达到最大(327.60μg·mL-1);在培养基中磷矿粉添加量和菌剂接种量分别为4.0g·L-1和11mL·L-1,50℃下培养22d后,接种解磷微生物的解磷率最大(37.55%)。  相似文献   
998.
Marine ecosystems cover more than 70% of the globe’s surface. These habitats are occupied by a great diversity of marine organisms that produce highly structural diverse metabolites as a defense mechanism. In the last decades, these metabolites have been extracted and isolated in order to test them in different bioassays and assess their potential to fight human diseases. Since traditional extraction techniques are both solvent- and time-consuming, this review emphasizes alternative extraction techniques, such as supercritical fluid extraction, pressurized solvent extraction, microwave-assisted extraction, ultrasound-assisted extraction, pulsed electric field-assisted extraction, enzyme-assisted extraction, and extraction with switchable solvents and ionic liquids, applied in the search for marine compounds. Only studies published in the 21st century are considered.  相似文献   
999.
Marine molluscs from the family Muricidae hold great potential for development as a source of therapeutically useful compounds. Traditionally known for the production of the ancient dye Tyrian purple, these molluscs also form the basis of some rare traditional medicines that have been used for thousands of years. Whilst these traditional and alternative medicines have not been chemically analysed or tested for efficacy in controlled clinical trials, a significant amount of independent research has documented the biological activity of extracts and compounds from these snails. In particular, Muricidae produce a suite of brominated indoles with anti-inflammatory, anti-cancer and steroidogenic activity, as well as choline esters with muscle-relaxing and pain relieving properties. These compounds could explain some of the traditional uses in wound healing, stomach pain and menstrual problems. However, the principle source of bioactive compounds is from the hypobranchial gland, whilst the shell and operculum are the main source used in most traditional remedies. Thus further research is required to understand this discrepancy and to optimise a quality controlled natural medicine from Muricidae.  相似文献   
1000.
Ocean warming and acidification are current global environmental challenges impacting aquatic organisms. A shift in conditions outside the optimal environmental range for marine species is likely to generate stress that could impact metabolic activity, with consequences for the biosynthesis of marine lipids. The aim of this study was to investigate differences in the lipid content of Dicathais orbita exposed to current and predicted future climate change scenarios. The whelks were exposed to a combination of temperature and CO2-induced acidification treatments in controlled flowthrough seawater mesocosms for 35 days. Under current conditions, D. orbita foot tissue has an average of 6 mg lipid/g tissue, but at predicted future ocean temperatures, the total lipid content dropped significantly, to almost half. The fatty acid composition is dominated by polyunsaturated fatty acids (PUFA 52%) with an n-3:6 fatty acid ratio of almost 2, which remains unchanged under future ocean conditions. However, we detected an interactive effect of temperature and pCO2 on the % PUFAs and n-3 and n-6 fatty acids were significantly reduced by elevated water temperature, while both the saturated and monounsaturated fatty acids were significantly reduced under increased pCO2 acidifying conditions. The present study indicates the potential for relatively small predicted changes in ocean conditions to reduce lipid reserves and alter the fatty acid composition of a predatory marine mollusc. This has potential implications for the growth and survivorship of whelks under future conditions, but only minimal implications for human consumption of D. orbita as nutritional seafood are predicted.  相似文献   
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