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81.
虾-鱼-贝-藻生态优化养殖及其水质生物调控技术研究 总被引:7,自引:0,他引:7
建立了一种虾、鱼、贝、藻多池循环水生态优化养殖模式及水质生物调控系统,包括对虾养殖、鱼类养殖、贝类养殖和大型海藻栽培等4个不同功能养殖区,1个水处理区以及1条应急排水渠。通过在封闭循环系统内不同池塘中放养生态位互补的经济动植物对虾池水环境进行生物调控。结果表明,循环水养殖系统内虾池水层悬浮物数量、COD值、氨态氮和硝酸态氮含量比对照组对虾单养池明显降低(P<0·01)。养殖排放水不处于富营养化状态(E<1)。对虾饲料产出对虾0.667kg·kg-1、罗非鱼0.037kg·kg-1、牡蛎0.738kg·kg-1、江蓠0.437kg·kg-1,净增产值2.01元。投入产出比由对虾单养的0.588降低为优化生态养殖的0.235。该养殖模式不仅实现了虾池水环境的生物调控与养殖用水的零排放,且显著提高了饲料利用率和经济效益,具有防病、环保、高效等优点。 相似文献
82.
测定反刍动物的采食、反刍和静颚行为及其时间分配是研究动物野外营养生态学和资源利用机制中不可缺少的技术手段.我们根据反刍动物采食、反刍和静颚时颚部的活动特点开发了采食行为遥测笼头,并于2005年7月试用于野生成年雌性海南坡鹿.该采食行为遥测笼头由颚部活动测定部分和无线电信号发射回路组成,使用同一频率发射颚部活动信号和用于遥测动物位置的间歇式无线电信号.颚部活动信号可以接收并录制成模拟声音信号,将其转化为数字信号后按照其信号频度即可区分采食、反刍和静颚行为.在海南坡鹿的试用中测得围栏外坡鹿个体的采食、反刍和休息时间组成分别为12%、36%和52%,围栏内个体为3%、38%和59%,显示存在被测定动物具有初始适应问题.作者预计将来把GPS装置植入该装置,并结合便携式计算机和GIS平台开发能够实时测定反刍动物采食行为活动和地理位置的遥测系统. 相似文献
83.
The feasibility of employing a non-ionic surfactant (Triton X-100) as an alternative and effective solvent for the microwave-assisted extraction of glycyrrhizic acid and liquiritin from liquorice root has been demonstrated. When compared with commonly used solvents, 5% Triton X-100 yielded higher extraction efficiency than aqueous solutions of ethanol or methanol. Under optimal conditions, i.e. 5% Triton X-100 (v/v) and microwave-assisted extraction for 3-5 min at 100 degrees C, the percentage extraction of active ingredients reached the highest value. The pre-concentration factor for the glycyrrhizic acid and liquiritin was about 13, and the cloud-point extraction recoveries for the two ingredients were 98.4 and 96.1%, respectively. The results showed that the coupling of microwave-assisted extraction and cloud-point extraction could be employed as a new and effective approach for the rapid extraction and pre-concentration of pharmacologically active ingredients from liquorice root without disturbing the subsequent chromatographic analysis. 相似文献
84.
Two new dimeric naphtho-gamma-pyrones, compounds 1 and 2, were isolated from the AcOEt extract of the fungal strain WZ-4-11 of Aspergillus carbonarius, together with eight known analogues, including 10,10'-bifonsecin B (3), 6'-O-demethylnigerone (4), nigerone (5), isonigerone (6), fonsecin (7), rubrofusarin B (8), TMC 256A1 (9), and flavasperone (10). Their structures were elucidated by means of UV, CD, IR, and 1D- and 2D-NMR spectroscopy, in combination with HR-MS analysis. The fully assigned (1)H- and (13)C-NMR data of 3, and the (13)C-NMR data of 6 are reported for the first time. Compounds 1 and 2 showed weak antimycobacterial activities against Mycobacterium tuberculosis H37Rv, with MIC values of 43.0 and 21.5 microM, resp. 相似文献
85.
Six new ergosterols from the marine-derived fungus Rhizopus sp 总被引:1,自引:0,他引:1
Six new ergosterols, including 3beta-hydroxyl-(22E, 24R)-ergosta-5,8,22-trien-7,15-dione (1), 3beta-hydroxyl-(22E, 24R)-ergosta-5,8,14,22-tetraen-7-one (2), 3beta,15beta-dihydroxyl-(22E, 24R)-ergosta-5,8(14),22-trien-7-one (3), 3beta,15alpha-dihydroxyl-(22E, 24R)-ergosta-5,8(14),22-trien-7-one (4), 3beta-hydroxyl-(22E, 24R)-ergosta-5,8(14),22-trien-7,15-dione (5), and 5alpha,8alpha-epidioxy-23,24(R)-dimethylcholesta-6,9(11),22-trien-3beta-ol (6), have been isolated from the marine-derived fungus Rhizopus sp., along with four known ones (7-10). The structures of the new compounds were determined on the basis of extensive spectroscopic data. All compounds were evaluated for their cytotoxic activities on P388, A549, HL-60, and BEL-7420 cell lines by the MTT and SRB methods. 相似文献
86.
Wenhao Chen Chunming Xu Bing Zhao Xiaodong Wang Yuchun Wang 《Acta Physiologiae Plantarum》2008,30(1):121-127
The aluminum (Al) tolerance of saffron (Crocus sativus L.) in hydroponics and the method of improving Al tolerance were investigated. Compared with the Al-free control, saffron
root elongation was decreased by 59.3 and 75% at 0.05 and 0.2 mM Al stress, respectively. At 0.5 mM Al stress, the root elongation
was inhibited completely. Addition of 1 mM polyamines improved saffron root growth markedly at 0.2 mM Al stress. Putrescine
(Put) showed better amelioration effect than spermidine (Spd) and spermine (Spm). The root elongation in Put treatment was
only 15% lower than that of Al-free control. The alleviation of Al rhizotoxicity by polyamines might be attributed to lower
Al content in the root tips, and subsequent less lipid peroxidation and oxidative stress. Higher activities of amine oxidases
and Hydrogen peroxide (H2O2) content might decrease the effects of Spd and Spm on alleviating oxidative damage compared with that of Put. 相似文献
87.
Hui Guo Kexu Li Wei Wang Chenggui Wang Yuchun Shen 《Biological trace element research》2017,179(2):318-326
Copper, a common chemical contaminant in aquatic environment, is known to be toxic to aquatic life at high concentrations. In the present study, we evaluated the apoptotic cell ratio and ROS production in hemocytes of the white shrimp Litopenaeus vannamei exposed to 1 or 5 mg L?1 Cu for 0, 3, 6, 12, 24, and 48 h. The expression changes of antioxidant biomarker genes, i.e., copper-zinc superoxide dismutase (Cu-Zn SOD) and catalase (CAT), apoptosis-related genes, i.e., caspase-3 and inhibitor of apoptosis protein (IAP), and a specific biomarker gene of heavy metal pollution, i.e., metallothionein (MT), were also determined in hemocytes. Significant increases in ROS production were observed in both treatment groups at each time points. The apoptotic cell ratios were significantly increased at 6–48 h among shrimp exposed to 1 mg L?1 Cu and at each time points in 5 mg L?1 Cu group. These results indicated that Cu would induce oxidative stress and apoptosis in the hemocyte of L. vannamei. Quantitative real-time PCR analysis revealed that the relative expression levels of Cu-Zn SOD, CAT, caspase-3, IAP, and MT were upregulated in a dose-dependent and time-dependent manner, suggesting the involvement of these genes in stress response against Cu exposure. 相似文献
88.
89.
条斑病是水稻(Oryza sativa)中的常见病害, 已经对我国粮食的高产稳产造成严重威胁。以典型籼稻台中本地1号与粳稻春江06的杂交F1代花药培养双单倍体群体(DH)为材料, 用Xoc BLS256进行人工接菌, 对双亲及群体各株系的病斑长度进行测量和量化分析; 同时利用该群体业已构建的加密遗传图谱对病斑表型数据进行QTL作图分析。结果在水稻第2、4、5和8号染色体上共检测到4个效应值能区分开的QTL。对2号与5号染色体上2个较大的QTL区间内抗条斑病相关基因进行了表达分析, 结果表明这些基因在处理前后出现了不同程度的表达差异, 暗示这些基因可能是响应春江06与台中本地1号条斑病抗性差异的目标基因。研究结果为进一步克隆水稻条斑病抗性QTL奠定了重要基础。 相似文献
90.
Callus cultures of Saussurea medusa were cultivated on solid culture medium supplemented with either Ce3+, La3+, Nd3+ or a mixture of rare earth elements. Ce3+, 0.05 mM, gave the highest biomass (0.53 g dry wt per flask) and total flavonoids (27.5 mg per flask), which were, 70% and 100% higher than those without Ce3+ addition, respectively. Ce3+, 0.01–0.1 mM, or La3+, 0.05 mM, or the mixture of rare earth elements, 0.025–0.1 mM, can substitute for 6-benzyladenine, and 0.025 mM Ce3+ can partly substitute for naphthaleneacetic acid in promoting cell growth and biosynthesis of total flavonoids in S. medusa. 相似文献