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971.
Andrew Pullin Geoff Frampton Rob Jongman Christian Kohl Barbara Livoreil Alexandra Lux György Pataki Gillian Petrokofsky Aranka Podhora Heli Saarikoski Luis Santamaria Stefan Schindler Isabel Sousa-Pinto Marie Vandewalle Heidi Wittmer 《Biodiversity and Conservation》2016,25(7):1285-1300
Responding to different questions generated by biodiversity and ecosystem services policy or management requires different forms of knowledge (e.g. scientific, experiential) and knowledge synthesis. Additionally, synthesis methods need to be appropriate to policy context (e.g. question types, budget, timeframe, output type, required scientific rigour). In this paper we present a range of different methods that could potentially be used to conduct a knowledge synthesis in response to questions arising from knowledge needs of decision makers on biodiversity and ecosystem services policy and management. Through a series of workshops attended by natural and social scientists and decision makers we compiled a range of question types, different policy contexts and potential methodological approaches to knowledge synthesis. Methods are derived from both natural and social sciences fields and reflect the range of question and study types that may be relevant for syntheses. Knowledge can be available either in qualitative or quantitative form and in some cases also mixed. All methods have their strengths and weaknesses and we discuss a sample of these to illustrate the need for diversity and importance of appropriate selection. To summarize this collection, we present a table that identifies potential methods matched to different combinations of question types and policy contexts, aimed at assisting teams undertaking knowledge syntheses to select appropriate methods. 相似文献
972.
973.
流行性出血热地鼠肾细胞灭活疫苗人体试用细胞免疫反应观察 总被引:2,自引:0,他引:2
观察了20位志愿者在接种试验性流行性出血热(EHF)地鼠肾细胞(GHKC)双价灭活疫苗后的细胞免疫反应,并以其体液免疫反应作对照观察。用淋巴细胞转化试验测定细胞免疫水平。结果首针疫苗接种后42天和56天,特异性刺激指数(SSI)和非特异性刺激指数(NSI)均较免疫前显著增高(P_(SSI)<0.001;P_(NSI)<0.02),免疫后SSI累计阳转率为100%,NSI累计阳转率为60%,免疫后6个月二者均降低至正常水平。免疫后56天测定抗体,荧光抗体阳转率为100%;微量感染性中和试验表明,针对家鼠型病毒L99株中和抗体阳转率为95%,而针对野鼠型病毒JR株阳转率为65%。 相似文献
974.
975.
桂西壮族手皮纹的分析 总被引:4,自引:0,他引:4
本文对广西西部500例健康壮族大、中学生的手皮纹进行了观察分析,计算出各型指纹频率、指纹脊线总数、指纹频度指数、atd角度、a-b脊线数、τ距比、主线横向指数、皮纹花样出现率、掌褶纹出现率共九项基本参数,并将这些数值与汉族作了比较,桂西壮族的手纹与汉族既有相似之处,又有本民族的特点。 相似文献
976.
Structural variation in human apolipoprotein E3 and E4: secondary structure, tertiary structure, and size distribution
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Chou CY Lin YL Huang YC Sheu SY Lin TH Tsay HJ Chang GG Shiao MS 《Biophysical journal》2005,88(1):455-466
Human apolipoprotein E (apoE) is a 299-amino-acid protein with a molecular weight of 34 kDa. The difference between the apoE3 and apoE4 isoforms is a single residue substitution involving a Cys-Arg replacement at residue 112. ApoE4 is positively associated with atherosclerosis and late-onset and sporadic Alzheimer's disease (AD). ApoE4 and its C-terminal truncated fragments have been found in the senile plaques and neurofibrillary tangles in the brain of AD patients. However, detail structural information regarding isoform and domain interaction remains poorly understood. We prepared full-length, N-, and C-terminal truncated apoE3 and apoE4 proteins and studied their structural variation. Sedimentation velocity and continuous size distribution analysis using analytical ultracentrifugation revealed apoE3(72-299) as consisting of a major species with a sedimentation coefficient of 5.9. ApoE4(72-299) showed a wider and more complicated species distribution. Both apoE3 and E4 N-terminal domain (1-191) existed with monomers as the major component together with some tetramer. The oligomerization and aggregation of apoE protein increased when the C-terminal domain (192-271) was incorporated. The structural influence of the C-terminal domain on apoE is to assist self-association with no significant isoform preference. Circular dichroism and fluorescence studies demonstrated that apoE4(72-299) possessed a more alpha-helical structure with more hydrophobic residue exposure. The structural variation of the N-terminal truncated apoE3 and apoE4 protein provides useful information that helps to explain the greater aggregation of the apoE4 isoform and thus has implication for the involvement of apoE4 in AD. 相似文献
977.
Can Baysal Luisa Bortesi Changfu Zhu Gemma Farré Stefan Schillberg Paul Christou 《Molecular breeding : new strategies in plant improvement》2016,36(8):108
Genome editing with the CRISPR/Cas9 system allows mutations to be induced at any 20-bp target site in the genome preceded by the short protospacer adjacent motif (PAM) 5′-NGG-3′. The brevity and degeneracy of the PAM ensures that the motif occurs every ~10 bp in plant genomes, and all plant genes therefore contain many targetable sites. However, the CRISPR/Cas9 system tolerates up to three mismatches in the target site, so the ability to target genes in a specific manner requires the design of synthetic guide RNAs (sgRNAs) that do not bind off-target sites anywhere else in the genome. This is straightforward for single-copy genes but more challenging if a target gene has one or more paralogs because the principles that balance targeting efficiency (the frequency of on-target mutations) and accuracy (the absence of off-target mutations) are not fully understood and may be partially species-dependent. To investigate this phenomenon in rice, we targeted the rice starch branching enzyme IIb gene (OsBEIIb) with two sgRNAs designed to differ at two and six positions, respectively, from corresponding sites in the close paralog OsBEIIa. In each case, half of the mismatches were in the essential seed region immediately upstream of the PAM, where exact pairing is thought to be necessary, and the other half were in the distal part of the target. The sgRNAs also differed in predicted targeting efficiency (39 and 96 %, respectively). We found that the sgRNA with the low predicted efficiency was actually the most efficient in practice, achieving a mutation frequency of 5 % at the target site, whereas the sgRNA with the high predicted efficiency generated no mutations at the second target site. Furthermore, neither of the sgRNAs induced an off-target mutation in the OsBEIIa gene. Our data indicate that efficiency predictions should be tested empirically because they do not always reflect the experimental outcome and that a 1-bp mismatch in the seed region of a sgRNA is sufficient to avoid off-target effects even in closely related rice genes. 相似文献
978.
Ana O. Fagundes Maira R. Aguiar Claudia S. Aguiar Giselli Scaini Monique U. Sachet Nayara M. Bernhardt Gislaine T. Rezin Samira S. Valvassori João Quevedo Emilio L. Streck 《Neurochemical research》2010,35(11):1675-1680
Methylphenidate is commonly used for the treatment of attention deficit/hyperactivity disorder. There are still few works
regarding the effects of methylphenidate on brain energy metabolism. Thus, in the present study we evaluated the effect of
chronic administration of methylphenidate on the activities of mitochondrial respiratory chain complexes I and III in the
brain of young rats. The effect of acute administration of methylphenidate on mitochondrial respiratory chain complexes I,
II, III and IV in the brain of young rats was also investigated. For acute administration, a single injection of methylphenidate
was given to rats on postnatal day 25. For chronic administration, methylphenidate injections were given starting at postnatal
day 25 once daily for 28 days. Our results showed that complexes I and III were not affected by chronic administration of
methylphenidate. Moreover, the acute administration of methylphenidate decreased complex I activity in cerebellum and prefrontal
cortex, whereas complexes II, III and IV were not altered. 相似文献
979.
肖黄栌红色素的理化性质研究 总被引:3,自引:0,他引:3
本文研究了肖黄栌红色素的提取 ,并研究了不同糖浓度、温度、光照、紫外线、Na2 HPO4 -KH2 PO4 缓冲液、维生素C、氧化剂H2 O2 、还原剂Na2 SO3 等对肖黄栌红色素稳定性的影响。结果表明 ,肖黄栌红色素适应的pH范围较广、抗热、抗氧化、抗还原、耐糖、耐维生素C。因而是一种有重要开发价值的天然红色素 相似文献
980.
K. M. Bhaskara Reddy Dokka Mallikarjunasarma Kamana Bulliraju Vanjivaka Sreelatha Y. Bharathi Kumari Ramesh Dandala Kuppanna Ananda 《International journal of peptide research and therapeutics》2011,17(2):113-121