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41.
A critical analysis is presented of the reports produced by four Technical Expert Working Group Sub-groups (SGs) on Ethical Review, Cost-Benefit, Authorisation and Scope, which were published on the EC website (http://ec.europa.eu/environment/chemicals/lab_animals/ia_info_en.htm), as part of the European Commission (EC)s review of EU Directive 86/609 EEC. This is in addition to our official response to the internet consultation questionnaire, submitted to the Commission on behalf of FRAME. Whilst the respective SG reports were extensive and detailed, we have identified several shortcomings, and in particular, a frequent lack of consensus among the SG members, resulting in a lack of clear guidance for the EC on what the revised Directive should contain, with reference to a number of crucial issues. Such indecisiveness could lead to wide discrepancies in the approaches of the EC, the European Parliament and the EU Member States concerning many issues of importance to animal welfare and the implementation of alternatives to animal experiments. These concerns range from logistical issues, such as requirements for named officers in authorised establishments, and the recording and publishing of statistics on animal use, to ethical and scientific problems, including the use of non-human primates, local ethical review, and education and training on the essential link between the Three Rs concept and best scientific practice. In each case, the basis for our concerns is explained, and suggestions for improvements to be incorporated into the revised Directive are made, in the hope that the harmonisation of approaches to laboratory animal experimentation and the use of alternative methods in the Member States can be maximised. 相似文献
42.
A. H. Nagy Dr. M. O. Siddiqui Z. G. Kocsis G. Vida 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1980,57(4):75-78
Summary Two allelic forms of NAD specific malate dehydrogenase were found in samples of a wild population of Corydalis solida. The dimeric nature and the origin of the heterodimeric form has been demonstrated by in vitro dissociation and recombination of the subunits detected by subsequent electrophoresis. The method is applicable for polyacrylamide gel electrophoresis of crude leaf extracts of individual MDH isozyme forms. 相似文献
43.
Cluster-root formation, carboxylate exudation and proton release of Lupinus pilosus Murr. as affected by medium pH and P deficiency 总被引:2,自引:0,他引:2
The study examined the interactive effect of pH and P supply on cluster-root formation, carboxylate exudation and proton release by an alkaline-tolerant lupin species (Lupinus pilosus Murr.) in nutrient solution. The plants were exposed to 1 (P1, deficient) and 50 μM P (P50, adequate) for 34 days in nutrient solution at either pH 5.6 or 7.8. Plant biomass was not influenced by pH at P1, but at P50 shoot and root dry weights were 23 and 18% higher, respectively, at pH 7.8 than at pH 5.6. There was no significant difference in plant biomass between two P treatments regardless of medium pH. Phosphorus deficiency increased significantly the number of the second-order lateral roots compared with the P50 treatment. Both total root length and specific root length of plants grown at pH 5.6 were higher than those at pH 7.8 regardless of P supply. Cluster roots were formed at P1, but cluster-root number was 2-fold higher at pH 7.8 than pH 5.6. Roots released 16 and 31% more protons at pH 5.6 and 7.8, respectively, in P1 than in P50 treatments, and the rate of proton release followed the similar pattern. At pH 5.6, citrate exudation rate was 0.39 μmol g−1 root DW h−1 at P1, but was under the detection limit at P50; at pH 7.8, it was 2.4-fold higher in P1 than in P50 plants. High pH significantly increased citrate exudation rate in comparison to pH 5.6. The uptake of anions P and S was inhibited at P1 and high pH increased cations Na, Mg and Ca uptake. The results suggested that enhanced cluster-root formation, proton release and citrate exudation may account for the mechanism of efficient P acquisition by alkaline-tolerant L. pilosus well adapted to calcareous soils. Cluster-root formation and citrate exudation in L. pilosus can be altered by medium pH and P deficiency. Phosphorus deficiency-induced proton release may be associated with the reduced anion uptake, but high pH-induced proton release may be partly attributed to increased cation uptake. 相似文献
44.
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46.
Nucleotide sequence and style-specific expression of a novel proline-rich protein gene from Nicotiana alata 总被引:4,自引:0,他引:4
cDNA clones encoding a novel proline-rich protein (NaPRP4) have been isolated from a Nicotiana alata stylar cDNA library. The N-terminal part of the derived protein is highly rich in proline (32.2%) and contains several repeats such as Lys-Pro-Pro (7 times) and Pro-Thr-Lys-Pro-Pro-Thr-Tyr-Ser-Pro-Ser-Lys-Pro-Pro (twice); the C-terminal part, on the other hand, has a lower proline content (9.9%) and contains two potential N-glycosylation sites and all the six cysteine residues. Northern blot and in situ hybridisation analyses indicate that expression of the NaPRP4 gene is restricted to cells of the transmitting tract of the style. 相似文献
47.
BackgroundFaculty vitality is the main ingredient to enhance professional education and competence. Enriching the faculty vitality in key domains of teaching, assessing, research, professionalism, and administration is perceived to improve educational environment significantly and enhances the academic performance of learners. Faculty development program (FDP) has been considered as a stand-alone educational pedagogy in fostering knowledge and professional skills of faculty. However, few studies have provided objective reports about the impact of such programs in a healthcare system.MethodsThis research was conducted by selecting data sources of PubMed-Medline, Wiley online library, Cochrane library, Taylor & Francis Online, CINAHL, Springer link, Proquest, ISI Web of knowledge, ScienceDirect, EJS, EBSCO, Blackwell, Emerald and ABI Inform. This search followed a step-wise approach defined by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). A total of 37 studies that explored the impact of FDPs on medical and allied health faculty’s professional development were selected.ResultsThis meta-analysis reported a mean effect size of 0.73 that reflects a significant and positive impact of FDPs in enhancing faculty’s knowledge and professional competence (z-statistics of 4.46 significant at p-value < 0.05) using the random effects model and forest plot.ConclusionThis article reiterates the incorporation of FDPs in all healthcare institutions for improving the academic performance of faculty with resultant enrichment of learners’ knowledge and skills. 相似文献
48.
Xi Chen Przemyslaw Kowal Sarah Hamad Hongni Fan Peng George Wang 《Biotechnology letters》1999,21(12):1131-1135
The gene galE encoding UDP-galactose 4-epimerase was cloned into E. coli BL21(DE3) from the chromosomal DNA of E. coli strain K-12. High expression of the soluble recombinant epimerase was achieved in the cell lysate. In order to evaluate the use of this epimerase in enzymatic synthesis of important -Gal epitopes (oligosaccharides with a terminal Gal1,3Gal sequence), a new radioactivity assay (1,3-galactosyltransferase coupled assay) was established to characterize its activity in producing UDP-galactose from UDP-glucose. Approximately 2700 units (100 mg) enzyme with a specific activity of 27 U mg–1 protein could be obtained from one liter of bacterial culture. The epimerase was active in a wide pH range with an optimum at pH 7.0. This expression system established a viable route to the enzymatic production of -Gal oligosaccharides to support xenotransplantation research. 相似文献
49.
Michael F. Dowe Jr. Gregg W. Roman Anita S. Klein 《Molecular & general genetics : MGG》1990,221(3):475-485
Summary The regulatory mutation bronze mutable 4 Derivative 6856 (bz-m4 D6856) contains a complex 6.7 kb Dissociation (Ds) element tagged with a duplication of low copy bz 3 flanking sequences (Klein et al. 1988). This creates a unique opportunity to study the transposition of a single member of the repetitive family of Ds elements. Eighteen full purple revertants (Bz alleles) of bz-m4 were characterized enzymatically and by genomic mapping. For 17 of the Bz alleles, reversion to a wild-type phenotype was caused by excision of the 6.7 kb Ds transposon. Nine of these Bz alleles retained the transposon somewhere in their genome. In this study we show that like Ac (Schwartz 1989; Dooner and Belachew 1989), the 6.7 kb Ds element can transpose within a short physical distance, both proximal and distal to its original position. Additional bz sequences have been mapped immediately distal to the mutant locus in bz-m4 D6856; genetic evidence suggests these are flanked by two additional Ds elements. The remaining Bz revertant, Bz :107, arose from excision of a more complex 13 kb Ds element. 相似文献
50.
Cui-Ping Cao Oliver Gailing Iskandar Z. Siregar Ulfah J. Siregar Reiner Finkeldey 《Tree Genetics & Genomes》2009,5(3):407-420
Shorea is the largest and most important genus of the Dipterocarpaceae. The genetic diversity and structure of nine Shorea species from two different locations, namely Nanjak Makmur in Sumatra and Sumalindo in Borneo, were evaluated using amplified
fragment length polymorphism (AFLP) markers. A total of 274 trees were investigated at 85 polymorphic AFLP loci. Levels of
genetic diversity of these species ranged from = 0.100 for S. acuminata to = 0.165 for S. blumutensis. The population of rare species S. blumutensis possessed the highest genetic diversity suggesting that geographically restricted species can have levels of genetic variation
comparable to closely related widespread common congeners. Analyses of molecular variance revealed that the genetic variation
was mainly found among species in both locations (57.7% in Sumatra; 56.3% in Borneo). The unweighted pairgroup method using
arithmetic averages dendrogram of all samples revealed an almost complete separation of species. Thus, AFLP markers proved
appropriate for phylogenetic studies of Shorea species. Specific markers have been detected showing high-frequency differences among species and between regions within
species. Sequence information of these markers can be used to develop specific polymerase chain reaction markers for wood
identification. The possibility of interspecific hybridization was discussed. 相似文献