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71.
We used the Mandarin Chinese version of the Camberwell Family Interview (CFI) to measure the components of expressed emotion among relatives of schizophrenic patients in urban and rural areas of Chengdu, China. The reliability and validity of the Chinese version of the CFI was examined. Seventy-one patients and their key relatives were included in the study. The results showed that high interrater reliabilities were found for the Chinese version of CFI. The proportion of relatives in our sample rated as high-EE was 28.2%, and the Chengdu relatives expressed significantly fewer critical comments (CCs) and less emotional overinvolvement (EOI) than respondents in other similar studies in the West. Within the Chengdu sample, city dwellers were significantly more expressive than villagers expressing warmth, positive remarks, and EOI (p<0.05). The results of this study could indicate the impact of cultural and ethnic differences and geographical location on EE.  相似文献   
72.
Two new anti-aging compounds, ganodermasides C and D, were isolated and their structures elucidated. They are novel ergosterols possessing a 4,6,8(14),22-tetraene-3-one unit with unique hydroxylation at C-9. Both of them significantly extended the replicative lifespan of the K6001 yeast strain. Ganodermasides C and D regulated the expression of the gene for UTH1 to prolong the replicative lifespan of yeast.  相似文献   
73.
A single nucleotide polymorphism (SNP) rs1122608 on chromosome 19p13.2 and in the BRG1/SMARCA4 gene was previously associated with coronary artery disease (CAD). CAD and ischemic stroke are both associated with atherosclerosis. Thus, we tested the hypothesis that rs1122608 is associated with ischemic stroke. Further studies were used to identify the most likely mechanism by which rs1122608 regulates atherosclerosis. For case–control association studies, two independent Chinese Han GeneID cohorts were used, including a Central cohort with 1,075 cases and 2,685 controls and the Northern cohort with 1,208 cases and 824 controls. eQTL and real-time RT-PCR analyses were used to identify the potential candidate gene(s) affected by rs1122608. The minor allele T of SNP rs1122608 showed significant association with a decreased risk of ischemic stroke in the Central GeneID cohort (adjusted P adj = 2.1 × 10?4, OR 0.61). The association was replicated in an independent Northern GeneID cohort (P adj = 6.00 × 10?3, OR 0.69). The association became more significant in the combined population (P adj = 7.86 × 10?5, OR 0.73). Allele T of SNP rs1122608 also showed significant association with a decreased total cholesterol level (P adj = 0.013). Allele T of rs1122608 was associated with an increased expression level of SFRS3 encoding an mRNA splicing regulator, but not with the expression of BRG1/SMARCA4 or LDLR (located 36 kb from rs1122608). Increased expression of SFSR3 may decrease IL-1β expression and secretion, resulting in reduced risk of atherosclerosis and stroke. This is the first study that demonstrates that rs1122608 confers protection against ischemic stroke and implicates splicing factor SFSR3 in the disease process.  相似文献   
74.
华北丽斑麻蜥食物同化和疾跑速的热依赖性   总被引:4,自引:4,他引:4  
罗来高  屈彦福  计翔 《动物学报》2006,52(2):256-262
作者研究山西阳泉丽斑麻蜥(Eremias argus)成体的选择体温、热耐受性及食物同化和疾跑速的热依赖性。选择体温、临界低温和临界高温无显著的两性差异,分别为36·0℃、1·0℃和44·9℃。在实验温度范围内,体温显著影响食物通过时间、日摄食量、日粪尿排量、表观消化系数和同化效率。食物通过时间在26 -34℃范围内随体温升高而缩短,在更高的体温下则延长。蜥蜴在30、32、34和36℃体温下明显摄入较多的食物、排出明显较多的粪尿。34℃和36℃下的表观消化系数和同化效率大于其它更低或更高温度下的对应数值,但这两个变量未因体温变化而呈现清晰的规律性变化。疾跑速在18 -36℃范围内随体温升高而加快,在38℃体温下则减缓。36℃或附近体温最适合疾跑速。疾跑速最适体温接近蜥蜴的选择体温,表明蜥蜴疾跑速的最适温度可能与其选择体温密切相关[动物学报52 (2) : 256 -262 , 2006]。  相似文献   
75.
为了研究AtNHX5基因在植物耐盐中的作用,构建了植物过量表达载体pROKⅡ-AtNHX5,并转化拟南芥。结果显示:(1)RT-PCR检测表明,转基因拟南芥中AtNHX5基因的表达大幅提高。(2)对转基因纯合株系进行耐盐性分析显示,AtNHX5过量表达提高了植株在种子萌发和苗期的耐盐性。(3)转基因植株在盐处理下的干重、鲜重以及地上部分Na+、K+含量均高于野生型对照。在200mmol/L NaCl处理下,以转基因株系a1-4为例,其地上部分单株鲜重、单株干重、K+含量分别是野生型的1.27、1.54、1.16倍,较野生型显著升高。研究表明,过量表达AtNHX5基因促进了盐胁迫下转基因植株对K+的吸收,转基因拟南芥的耐盐性明显提高。  相似文献   
76.
珍稀濒危植物的回归:理论和实践   总被引:1,自引:0,他引:1  
回归(reintroduction)指的是在一个物种出现濒危的现有分布区域或已经灭绝的历史分布区域内建立新种群的活动.作为物种保护及种群恢复的重要策略之一,回归在越来越多的珍稀濒危植物保护实践中得到了应用.回归的成功标准分为短期和长期两类,前者包括个体的成活、种群的建立和扩散:后者包括回归种群的自我维持和在生态系统中发挥功能等.珍稀濒危植物的回归是一项高风险和高花费的工程,需要根据种群遗传学和生态学理论,选择合适的繁殖体、扩繁方式、回归地点和生境、定植时间、定植方式等,还要考虑传粉者和共生物种,并开展回归后的长期监测.为保证回归的成功并把回归过程中可能对生态环境造成的不利影响降到最小,还需要防止遗传污染、避免源种群的过度采集、加强公众教育、加强长期监测等.不同植物的回归面临着各不相同的具体困难,兰科植物的回归面临更多的困难,如材料扩繁难与存活率低等.基于生态学、传粉生物学、繁殖技术、真菌学和种群遗传多样性研究基础上开展兰科植物的回归,被证明是有效的综合保护策略.  相似文献   
77.
Zhu  Dehuang  Hui  Dafeng  Wang  Mengqi  Yang  Qiong  Li  Zhen  Huang  Zijian  Yuan  Hanmeng  Yu  Shixiao 《Wetlands Ecology and Management》2021,29(1):129-141

Allometric growth reflects different allocation patterns and relationships of different components or traits of a plant and is closely related to ecosystem carbon storage. As an introduced species, the growth and carbon storage of Sonneratia apetala are still unclear. To derive allometric relationships of the mangrove S. apetala and to estimate carbon storage in mangrove ecosystems, we harvested 12 individual Sonneratia apetala trees from four different diameter classes in the Futian National Nature Reserve, Guangdong, China. Allometric growth models were fitted. The results showed that diameter at breast height (DBH) and wood density were better variables for predicting plant biomass (including above- and below-ground biomass) than plant height. There were significant power function relationships between biomass and DBH, with a mean allometric exponent of 2.22, and stem biomass accounted for 97% of the variation in S. apetala total biomass. Nearly isometric scaling relationships were developed between stem biomass and other biomass components. To better understand the carbon stocks of the S. apetala ecosystem, we categorized all trees into five age classes and quantified vegetation carbon storage. The S. apetala vegetation carbon storage ranged from 96.48 to 215.35 Mg C ha?1, and the carbon storage significantly increased with stand age. The allometric equations developed in this study are useful to estimate biomass and carbon storage of S. apetala ecosystems.

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78.
外源基因在大肠杆菌中表达是对基因重组技术的成功应用。外源基因在不同的大肠杆菌表达系统中表达产物可能定位于大肠杆菌空间结构的不同位置:胞质,胞质膜,胞周质,胞外膜和胞外培养基,五种表达定位方式各有其特点和用途 。  相似文献   
79.
甘蓝型油菜(Brassica napus L.)皖油14具柄子叶为外植体,进行安徽省地方性油菜品系离体培养再生植株体系的研究.通过不同浓度的激素组合实验,结果表明:在愈伤组织诱导中,以MS-C7(MS 2 mg/L6-BA 0.2mg/L NAA 0.25 mg/2,4-D 7.5 mg/L AgNO3)培养基的出愈率最高,且可产生大量绿色芽点;以MS-B3(MS 1.0 mg/L6-BA 0.1 mg/L NAA 7.5 mg/L AgNO3)培养基的芽苗分化率最高,可分化出丛生的不定芽;生根培养基MS 0.1 mg/L NAA 7.5 mg/L AgNO3的生根率达100%.7.5 mg/L的AgNO3可以明显减少愈伤组织的褐化,良好的空气流通可以减少玻璃苗的形成.初步建立了皖油14品系的高频再生植株体系.  相似文献   
80.
In order to investigate the epitope of basic fibroblast growth factor (bFGF) and its immunogenicity, the epitopes of bFGF were screened from the phage display library with monoclonal antibody GF22, which can neutralize the bio-activity of bFGF. By three rounds of screening, the positive phage clones with bFGF epitopes were selected, which can effectively block the bFGF to bind with GF22. Sequence analysis showed that the epitopes shared a highly conservative sequence (Leu-Pro-Pro/Leu-Gly-His-Phe/Ile-Lys). The sequence of PPGHFK was located at 22-27 of the bFGF. The specific immuno-response of mouse could be highly induced by phage clones with the epitopes. And the anti-bFGF activity induced by LPGHFK was 3 times higher than the original sequence, which showed that the mimetic peptide LPLGHIK might be used as a tumor vaccine in the prevention and treatment of tumor.  相似文献   
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