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81.

Background  

Multi-locus sequence typing (MLST) is a method of typing that facilitates the discrimination of microbial isolates by comparing the sequences of housekeeping gene fragments. The mlstdbNet software enables the implementation of distributed web-accessible MLST databases that can be linked widely over the Internet.  相似文献   
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A major challenge in controlling overabundant wildlife is monitoring their populations, particularly as they decline to very low density. Camera traps and wildlife detector dogs are increasingly being used for this purpose. We compared the cost-effectiveness of these two approaches for detecting feral cats (Felis catus) on two pastoral properties in Hawke's Bay, North Island, New Zealand. One property was subject to intensive pest removal, while the other had no recent history of pest control. Camera traps and wildlife detector dogs detected cats at similar rates at both sites. The operating costs of each method were also comparable. We identify a number of advantages and disadvantages of each technique, and suggest priorities for further research.  相似文献   
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Rush  JS; Waechter  CJ 《Glycobiology》1998,8(12):1207-1213
In the current model for Glc3Man9GlcNAc2-P-P-Dol assembly, Man5GlcNAc2- P-P-Dol, Man-P-Dol, and Glc-P-Dol are synthesized on the cytoplasmic face of the ER and diffuse transversely to the lumenal leaflet where the synthesis of the lipid-bound precursor oligosaccharide is completed. To establish the topological sites of Glc-P-Dol synthesis and the lipid-mediated glucosyltransfer reactions involved in Glc3Man9GlcNAc2-P-P-Dol synthesis in ER vesicles from pig brain, the trypsin-sensitivity of Glc-P-Dol synthase activity and the Glc-P- Dol:Glc0-2Man9GlcNAc2-P-P-Dol glucosyltransferases (GlcTases) was examined in sealed microsomal vesicles. Since ER vesicles from brain do not contain glucose 6-phosphate (Glc 6-P) phosphatase activity, the latency of the lumenally oriented, processing glucosidase I/II activities was used to assess the intactness of the vesicle preparations. Comparative enzymatic studies with sealed ER vesicles from brain and kidney, a tissue that contains Glc 6-P phosphatase, demonstrate the reliability of using the processing glucosidase activities as latency markers for topological studies with microsomal vesicles from non-gluconeogenic tissues lacking Glc 6-P phosphatase. The results obtained from the trypsin-sensitivity assays with sealed microsomal vesicles from brain are consistent with a topological model in which Glc-P-Dol is synthesized on the cytoplasmic face of the ER, and subsequently utilized by the three Glc-P-Dol-mediated GlcTases after "flip-flopping" to the lumenal monolayer.   相似文献   
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Objective: To determine which attributes of clinical practice guidelines influence the use of guidelines in decision making in clinical practice. Design: Observational study relating the use of 47 different recommendations from 10 national clinical guidelines to 12 different attributes of clinical guidelines—for example, evidence based, controversial, concrete. Setting: General practice in the Netherlands. Subjects: 61 general practitioners who made 12 880 decisions in their contacts with patients. Main outcome measures: Compliance of decisions with clinical guidelines according to the attribute of the guideline. Results: Recommendations were followed in, on average, 61% (7915/12 880) of the decisions. Controversial recommendations were followed in 35% (886/2497) of decisions and non-controversial recommendations in 68% (7029/10 383) of decisions. Vague and non-specific recommendations were followed in 36% (826/2280) of decisions and clear recommendations in 67% (7089/10 600) of decisions. Recommendations that demanded a change in existing practice routines were followed in 44% (1278/2912) of decisions and those that did not in 67% (6637/9968) of decisions. Evidence based recommendations were used more than recommendations for practice that were not based on research evidence (71% (2745/3841) v 57% (5170/9039)). Conclusions: People and organisations setting evidence based clinical practice guidelines should take into account some of the other important attributes of effective recommendations for clinical practice.

Key messages

  • Specific attributes of clinical practice guidelines determine whether they are used in practice
  • Evidence based recommendations are better followed in practice than recommendations not based on scientific evidence
  • Precise definitions of recommended performance improve the use of guidelines
  • Testing the feasibility and acceptance of clinical guidelines among the target group is important for effective implementation
  • People setting evidence based guidelines need to understand the attributes of effective guidelines
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Mitochondrial gene divergence of Colombian Drosophila pseudoobscura   总被引:1,自引:0,他引:1  
Isolated populations of drosophila pseudoobscura, separated from North American populations by about 2,400 km, were found in Colombia in 1960. We compared for sequences of the small ribosomal RNA (srRNA) gene on the mitochondria between North American and Colombian D. pseudoobscura in order to clarify the age of the Colombian isolates. The North American populations were not genetically different from each other but were genetically different from the Colombian populations. The Mexican strains represent the area from which the Colombian founders might have come. The estimated net nucleotide divergence between Mexican and Colombian D. pseudoobscura indicates that the Colombian population is not an ancient lineage. Phylogenies using both distance and parsimony methodologies reinforced this conclusion. The Colombian samples group together with both methods but, according to the bootstrap analysis, not significantly. It appears that the populations have not been separated long enough for their DNA sequences to show much divergence.   相似文献   
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Background  

Various typing methods have been developed for Neisseria gonorrhoeae, but none provide the combination of discrimination, reproducibility, portability, and genetic inference that allows the analysis of all aspects of the epidemiology of this pathogen from a single data set. Multilocus sequence typing (MLST) has been used successfully to characterize the related organisms Neisseria meningitidis and Neisseria lactamica. Here, the same seven locus Neisseria scheme was used to characterize a diverse collection of N. gonorrhoeae isolates to investigate whether this method would allow differentiation among isolates, and to distinguish these three species.  相似文献   
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