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991.
992.
云南省香格里拉大峡谷藏族神山在自然保护中的意义   总被引:11,自引:1,他引:11  
位于云南省西北部迪庆藏族自治州境内的香格里拉大峡谷拥有独特的自然人文景观和丰富的生物多样性。藏族作为当地最重要的原住民族,他们的文化对当地的自然环境具有重要的影响。为了解藏族传统文化中的神山崇拜对香格里拉大峡谷地区自然环境的影响,本文应用民族生态学、植物生态学和文化人类学的研究方法,结合文献资料的分析,对香格里拉大峡谷的藏族神山进行了调查和研究,并对处于不同保护状态下(神山与非神山)的两个典型植物群落即高山松(Pinus densata)群落和云南黄果冷杉(Abies ernestii var. salouenensis)群落进行了比较。结果显示,在相同的样地面积内(20 m×20 m),神山植物群落在物种数量(20,14)和群落盖度(100%,85%)方面都明显高于非神山植物群落(11,2;70%,60%)。结合入户调查资料,发现广泛分布于香格里拉大峡谷的藏族神山构成了一个“自下而上”的乡土保护体系,它不仅在保护生物多样性、维护当地脆弱的生态环境等方面发挥着重要的作用,而且还可以提供多种非林产品,实现多种生态功能。文章探讨了发挥乡土保护体系的保护功效及应用传统文化知识以促进自然保护的重要性,建议应当尊重和保护原住民的传统文化,发掘其中优秀的自然保护知识和经验,引导其发挥更加有效的自然保护功能,使民族传统保护体系成为现代自然保护体系的有力补充。  相似文献   
993.
L Zhang  J Luo  M Hao  L Zhang  Z Yuan  Z Yan  Y Liu  B Zhang  B Liu  C Liu  H Zhang  Y Zheng  D Liu 《BMC genetics》2012,13(1):69-8
ABSTRACT: BACKGROUND: A synthetic doubled-haploid hexaploid wheat population, SynDH1, derived from the spontaneous chromosome doubling of triploid F1 hybrid plants obtained from the cross of hybrids Triticum turgidum ssp. durum line Langdon (LDN) and ssp. turgidum line AS313, with Aegilops tauschii ssp. tauschii accession AS60, was previously constructed. SynDH1 is a tetraploidization-hexaploid doubled haploid (DH) population because it contains recombinant A and B chromosomes from two different T. turgidum genotypes, while all the D chromosomes from Ae. tauschii are homogenous across the whole population. This paper reports the construction of a genetic map using this population. RESULTS: Of the 606 markers used to assemble the genetic map, 588 (97%) were assigned to linkage groups. These included 513 Diversity Arrays Technology (DArT) markers, 72 simple sequence repeat (SSR), one insertion site-based polymorphism (ISBP), and two high-molecular-weight glutenin subunit (HMW-GS) markers. These markers were assigned to the 14 chromosomes, covering 2048.79 cM, with a mean distance of 3.48 cM between adjacent markers. This map showed good coverage of the A and B genome chromosomes, apart from 3A, 5A, 6A, and 4B. Compared with previously reported maps, most shared markers showed highly consistent orders. This map was successfully used to identify five quantitative trait loci (QTL), including two for spikelet number on chromosomes 7A and 5B, two for spike length on 7A and 3B, and one for 1000-grain weight on 4B. However, differences in crossability QTL between the two T. turgidum parents may explain the segregation distortion regions on chromosomes 1A, 3B, and 6B. CONCLUSIONS: A genetic map of T. turgidum including 588 markers was constructed using a synthetic doubled haploid (SynDH) hexaploid wheat population. Five QTLs for three agronomic traits were identified from this population. However, more markers are needed to increase the density and resolution of this map in the future study.  相似文献   
994.
Heterocyclic ketones as inhibitors of histone deacetylase   总被引:1,自引:0,他引:1  
Several heterocyclic ketones were investigated as potential inhibitors of histone deacetylase. Nanomolar inhibitors such as 22 and 25 were obtained, the anti-proliferative activity of which were shown to be mediated by HDAC inhibition.  相似文献   
995.
Mao L  Jiang S  Li G  He Y  Chen L  Yao Q  Chen K 《Current microbiology》2012,64(6):545-551
Human serum albumin (HSA) is the major protein component of human plasma. To date, HSA for clinical uses is mostly produced by fractionation of human whole blood, which is accompanied by a lot of limitations. To obtain long-term bioactive albumin, we used hsa as a foreign gene and constructed a recombinant plasmid pJS700-HSA which carries a recombinant gene cotC-hsa under the control of cotC promoter. Plasmid pJS700-HSA was transformed into Bacillus subtilis by double cross-over and an amylase inactivated mutant was produced. After induction of spore formation, western blot and fluorescence immunoassay were used to monitor HSA surface expression on spores. We estimated that HSA displayed on the spore accounted for 0.135 % of the total spore proteins and about 0.023 fg HSA were exposed on the surface of each spore. Oral administration to mice with spores displaying HSA implied that the recombinant spores may have potential ability to increase the serum albumin level in vivo due to the resistant characters of spores.  相似文献   
996.
Tillering contributes to grain yield and plant architecture and therefore is an agronomically important trait in sorghum (Sorghum bicolor). Here, we identified and functionally characterized a mutant of the Non‐dormant Axillary Bud 1 (NAB1) gene from an ethyl methanesulfonate‐mutagenized sorghum population. The nab1 mutants have increased tillering and reduced plant height. Map‐based cloning revealed that NAB1 encodes a carotenoid‐cleavage dioxygenase 7 (CCD7) orthologous to rice (Oryza sativa) HIGH‐TILLERING DWARF1/DWARF17 and Arabidopsis thaliana MORE AXILLARY BRANCHING 3. NAB1 is primarily expressed in axillary nodes and tiller bases and NAB1 localizes to chloroplasts. The nab1 mutation causes outgrowth of basal axillary buds; removing these non‐dormant basal axillary buds restored the wild‐type phenotype. The tillering of nab1 plants was completely suppressed by exogenous application of the synthetic strigolactone analog GR24. Moreover, the nab1 plants had no detectable strigolactones and displayed stronger polar auxin transport than wild‐type plants. Finally, RNA‐seq showed that the expression of genes involved in multiple processes, including auxin‐related genes, was significantly altered in nab1. These results suggest that NAB1 functions in strigolactone biosynthesis and the regulation of shoot branching via an interaction with auxin transport.  相似文献   
997.
As an Old World nonhuman primate, baboons have been extensively used for research on dyslipidemia and atherogenesis. With increasing knowledge about the endothelium's role in the initiation and progression of atherosclerosis, the value of the baboon model can be increased by developing it for research on the role of dysfunctional endothelium in atherogenesis. Toward that goal, we have established and validated methods of isolating and culturing baboon femoral artery endothelial cells (BFAECs) and compared baboon endothelial cellular characteristics with those of humans. Our results indicated that baboon and human endothelial cells share similar growth and culture behaviors. As was the case for human endothelial cells, BFAECs responded to tumor necrosis factor (TNF)-α stimulation with increased expression of adhesion molecules (maximum increase for intracellular adhesion molecule (ICAM): 1.76±0.26-fold; vascular cell adhesion molecule (VCAM): 1.65±0.25-fold; E-selectin: 2.86±0.57-fold). However, BFAECs were hyporesponsive to lipopolysaccharide (LPS) (range, 0.25–20 μg/mL) in adhesion molecule expression, whereas 1 μg/mL LPS induced 2.14- to 3.71-fold increases in human endothelial cells. The differential responses to LPS were not related to TLR-2 and toll-like receptor (TLR)-4 expression on the cell surface. And baboon microvascular endothelial cells had similar features as BFAECs. We observed constitutive expression of interleukin (IL)-6, IL-8, granulocyte macrophage colony-stimulating factor (GM-CSF), and monocyte chemoattractant protein (MCP)-1 in both human and baboon endothelial cells, and these cytokines were further induced by TNF-α and LPS. We also demonstrated that the responses to TNF-α or LPS varied among baboons maintained under the same dietary and environmental conditions, suggesting that response may be controlled by genetic factors.  相似文献   
998.
Changes in precipitation can influence soil water and nutrient availability, and thus affect plant nutrient conservation strategies. Better understanding of how nutrient conservation changes with variations in water availability is crucial for predicting the potential influence of global climate change on plant nutrient-use strategy. Here, green-leaf nitrogen (N) and phosphorus (P) concentrations, N- and P-resorption proficiency (the terminal N and P concentration in senescent leaves, NRP and PRP, respectively), and N- and P-resorption efficiency (the proportional N and P withdrawn from senescent leaves prior to abscission, NRE and PRE, respectively) of Leymus chinensis (Trin.) Tzvel., a typical perennial grass species in northern China, were examined along a water supply gradient to explore how plant nutrient conservation responds to water change. Increasing water supply at low levels (< 9000 mL/year) increased NRP, PRP and PRE, but decreased green-leaf N concentration. It did not significantly affect green-leaf P concentration or NRE. By contrast, all N and P conservation indicators were not significantly influenced at high water supply levels (> 9000 mL/year). These results indicated that changes in water availability at low levels could affect leaf-level nutrient characteristics, especially for the species in semiarid ecosystems. Therefore, global changes in precipitation may pose effects on plant nutrient economy, and thus on nutrient cycling in the plant-soil systems.  相似文献   
999.
1000.
普通玉米籽粒性状的遗传效应分析   总被引:4,自引:1,他引:4  
采用二倍体种子遗传模型及其分析方法,研究了5个玉米籽粒性状的直接效应、母体效应和细胞质效应.分析结果表明,各性状的遗传同时受种子直接效应和母体效应的影响,细胞质基因对百粒重和粒宽具有极显著影响.除粒长、粒厚的直接显性效应与母体显性效应间的协方差外,直接效应与母体效应间的协方差均不显著.因此,通过母体植株的表现可对这些性状进行有效的选择.S_22和 87-1是改良粒重的优良亲本.选择粒较宽的自交系作母本有利于提高后代选系及F_1的百粒重.  相似文献   
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