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61.
不结球白菜离体培养与植株再生体系研究   总被引:6,自引:2,他引:6  
以4个不结球白菜品种为试材,对外植体、苗龄、激素的组配、培养基中琼脂和AgNO3浓度等再生因素进行了筛选优化,并探讨了抗坏血酸(AsA)对不结球白菜不定芽分化的影响。结果显示:以4~7d苗龄的带柄子叶为外植体诱导不定芽效果较好;MN培养基中4mg/L6-BA与0.5mg/LNAA的搭配有利于不定芽形成;琼脂的浓度变化对不定芽分化影响较大,以9g/L琼脂为宜;培养基中添加5~7.5mg/L的AgNO3、0.1~0.5mmol/L的AsA可显著提高不定芽的发生频率和质量。通过不定芽继代培养、生根培养和驯化移栽建立了能够获得较高再生频率的不结球白菜离体再生体系。  相似文献   
62.
对海南岛野生土著药用木本植物区系的研究表明,该区系由70科206属332种组成,呈现出热带北缘特征,物种主要集中在岛南部、中南部和东南部地区。本文还对海南岛药用植物资源的应用现状及发展思路作了探讨。  相似文献   
63.
资源限制与发展停滞:传统社会的生态学分析   总被引:4,自引:0,他引:4  
资源限制与发展停滞:传统社会的生态学分析王建革(复旦大学历史地理研究所,上海200433)ResourcesLimitationandSlowDevelopment:AnEcologicalAnalysisofTraditionalSociety.W...  相似文献   
64.
Although Platycodon grandiflorum (Jacq.) A.DC. is a renowned medicine food homology plant, reports of excessive cadmium (Cd) levels are common, which affects its safety for clinical use and food consumption. To enable its Cd levels to be regulated or reduced, it is necessary to first elucidate the mechanism of Cd uptake and accumulation in the plant, in addition to its detoxification mechanisms. This present study used inductively couple plasma-mass-spectrometry to analyze the subcellular distribution and chemical forms of Cd in different tissues of P. grandiflorum. The experimental results showed that Cd was mainly accumulated in the roots [predominantly in the cell wall (50.96%–61.42%)], and it was found primarily in hypomobile and hypotoxic forms. The proportion of Cd in the soluble fraction increased after Cd exposure, and the proportion of insoluble phosphate Cd and oxalate Cd increased in roots and leaves, with a higher increase in oxalate Cd. Therefore, it is likely that root retention mechanisms, cell wall deposition, vacuole sequestration, and the formation of low mobility and low toxicity forms are tolerance strategies for Cd detoxification used by P. grandiflorum. The results of this study provide a theoretical grounding for the study of Cd accumulation and detoxification mechanisms in P. grandiflorum, and they can be used as a reference for developing Cd limits and standards for other medicine food homology plants.  相似文献   
65.
探讨我国森林野生动物红外相机监测规范   总被引:1,自引:0,他引:1  
野生动物多样性是生物多样性监测与保护管理评价的关键指标, 因此对野生动物进行长期监测是中国森林生物多样性监测网络(CForBio)等大尺度生物多样性监测研究计划的一个重要组成部分。2011年以来, CForBio网络陆续在多个森林动态监测样地开展以红外相机来监测野生动物多样性。随着我国野生动物红外相机监测网络的初步形成, 亟待建立和执行基于红外相机技术的统一监测规范。基于3年来在我国森林动态监测样地红外相机监测的进展情况, 以及热带生态评价与监测网络针对陆生脊椎动物(兽类和鸟类)所提出的红外相机监测规范, 本文从监测规范和监测注意事项等方面探讨了我国森林野生动物红外相机监测的现状和未来。  相似文献   
66.
中国美利奴(新疆军垦型)绵羊9个微卫星基因座多态性研究   总被引:10,自引:1,他引:10  
赵宗胜  王根林  郭继刚  李大全 《遗传》2006,28(8):939-944
利用PCR技术和复合电泳银染技术检测中国美利奴(新疆军垦型)绵羊第1号染色体上BM6506,BM1824,BM6438, ILSTS004和OarDB6 等5个基因座和第6号染色体上 BM4621,OarHH55,BM143和OarJMP8 等4个基因座,共9个基因座的基因频率(Pi)、个体鉴别力(DP)、杂合度(H)、多态信息含量(PIC)、和非父排除概率(PE)。结果显示:9个微卫星基因座的基因型分布符合Hardy-Weinberg平衡,绵羊中9个微卫星基因座中BM4621 基因座的DP、H、PIC和PE都为最高。9个微卫星基因座的累积个体鉴别力(CDP)为0.99999,累积非父排除能力(CPE)为0.99915。结果显示9个微卫星基因座适用于中国美利奴(新疆军垦型)绵羊的遗传连锁分析、个体识别和亲权鉴定等研究领域。  相似文献   
67.
Several Vietnamese seaweed species have economic importance as food for humans, as industrial materials, as ingredients in traditional medicine, and as biofertilizers. The nutritional values of nine representative Vietnamese seaweed species were analyzed. In this report, all of the species studied are rich in proteins, lipids (especially polyunsaturated fatty acids), vitamins, pigments, and macro- and micro-elements. The effect of the physiological activities of the green alga, Ulva reticulata, on hepatic fatty acid metabolism were examined in mice. The results indicate that Vietnamese seaweeds are abundant and have high quality materials for industrial and agricultural purposes. Presented at the 6th Meeting of the Asian Pacific Society of Applied Phycology, Manila, Philippines.  相似文献   
68.
Thyrotropin (TSH) and the gonadotropins; follitropin (FSH), lutropin (LH) and human chorionic gonadotropin (hCG) are a family of heterodimeric glycoprotein hormones. These hormones composed of two noncovalently linked subunits; a common α and a hormone specific β subunits. Assembly of the subunits is vital to the function of these hormones. However, genetic fusion of the α and β subunits of hFSH, hCG and hTSH resulted in active polypeptides. The glycoprotein hormone subunits contain one (TSH and LH) or two (α, FSHβ and hCGβ) asparagine-linked (N-linked) oligosaccharides. CGβ subunit is distinguished among the β subunits because of the presence of a carboxyl-terminal peptide (CTP) bearing four O-linked oligosaccharide chains. To examine the role of the oligosaccharide chains on the structure–function of glycoprotein hormones, chemical, enzymatic and site-directed mutagenesis were used. The results indicated that O-linked oligosaccharides play a minor role in receptor binding and signal transduction of the glycoprotein hormones. In contrast, the O-linked oligosaccharides are critical for in vivo half-life and bioactivity. Ligation of the CTP bearing four O-linked oligosaccharide sites to different proteins, resulted in enhancing the in vivo bioactivity and half-life of the proteins. The N-linked oligosaccharide chains have a minor role in receptor binding of glycoprotein hormones, but they are critical for bioactivity. Moreover, glycoprotein hormones lacking N-linked oligosaccharides behave as antagonists. In conclusion, the O-linked oligosaccharides are not important for in vitro bioactivity or receptor binding, but they play an important role in the in vivo bioactivity and half-life of the glycoprotein hormones. Addition of the O-linked oligosaccharide chains to the backbone of glycoprotein hormones could be an interesting strategy for designing long acting agonists of glycoprotein hormones. On the other hand, the N-linked oligosaccharides are not important for receptor binding, but they are critical for bioactivity of glycoprotein hormones. Deletion of the N-linked oligosaccharides resulted in the development of glycoprotein hormone antagonists. In the case of hTSH, development of an antagonist may offer a novel therapeutic strategy in the treatment of thyrotoxicosis caused by Graves' disease and TSH secreting pituitary adenoma.  相似文献   
69.
Background As important components in saline agriculture, halophytes can help to provide food for a growing world population. In addition to being potential crops in their own right, halophytes are also potential sources of salt-resistance genes that might help plant breeders and molecular biologists increase the salt tolerance of conventional crop plants. One especially promising halophyte is Suaeda salsa, a euhalophytic herb that occurs both on inland saline soils and in the intertidal zone. The species produces dimorphic seeds: black seeds are sensitive to salinity and remain dormant in light under high salt concentrations, while brown seeds can germinate under high salinity (e.g. 600 mm NaCl) regardless of light. Consequently, the species is useful for studying the mechanisms by which dimorphic seeds are adapted to saline environments. S. salsa has succulent leaves and is highly salt tolerant (e.g. its optimal NaCl concentration for growth is 200 mm). A series of S. salsa genes related to salt tolerance have been cloned and their functions tested: these include SsNHX1, SsHKT1, SsAPX, SsCAT1, SsP5CS and SsBADH. The species is economically important because its fresh branches have high value as a vegetable, and its seed oil is edible and rich in unsaturated fatty acids. Because it can remove salts and heavy metals from saline soils, S. salsa can also be used in the restoration of salinized or contaminated saline land.Scope Because of its economic and ecological value in saline agriculture, S. salsa is one of the most important halophytes in China. In this review, the value of S. salsa as a source of food, medicine and forage is discussed. Its uses in the restoration of salinized or contaminated land and as a source of salt-resistance genes are also considered.  相似文献   
70.
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