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1.
Reconstructions of the human-African great ape phylogeny by using mitochondrial DNA (mtDNA) have been subject to considerable debate. One confounding factor may be the lack of data on intraspecific variation. To test this hypothesis, we examined the effect of intraspecific mtDNA diversity on the phylogenetic reconstruction of another Plio- Pleistocene radiation of higher primates, the fascicularis group of macaque (Macaca) monkey species. Fifteen endonucleases were used to identify 10 haplotypes of 40-47 restriction sites in M. mulatta, which were compared with similar data for the other members of this species group. Interpopulational, intraspecific mtDNA diversity was large (0.5%- 4.5%), and estimates of divergence time and branching order incorporating this variation were substantially different from those based on single representatives of each species. We conclude that intraspecific mtDNA diversity is substantial in at least some primate species. Consequently, without prior information on the extent of genetic diversity within a particular species, intraspecific variation must be assessed and accounted for when reconstructing primate phylogenies. Further, we question the reliability of hominoid mtDNA phylogenies, based as they are on one or a few representatives of each species, in an already depauperate superfamily of primates.   相似文献   
2.
An indicator for determination of beta-lactamase inhibitory activity of various compounds was developed. The method is based on the direct contact of beta-lactamase with the compounds tested. It excludes the use of test-bacteria and provides recording in the data on the day of the experiment. The indicator method enables the detection of the beta-lactamase inhibitory properties of both beta-lactamase inhibitors and beta-lactam antibiotics, not subjected to destruction by beta-lactamases. The method is likely to be fit for detection of atypical beta-lactams having beta-lactam groups in their molecules (bleomycin group). Antibiotics not belonging to the group of beta-lactams, such as gentamicin, sisomicin, lincomycin and fusidin showed no beta-lactamase inhibitory activity under the conditions of the indicator method. The use of the indicator method provided determination of the inhibitory activity with respect to penicillinase of Bac. licheniformis 749/C in 30 (8.5 per cent) out of 350 fermentation broths of actinomycetes.  相似文献   
3.
The substrate profiles and sensitivity to dicloxacillin inhibition were studied in the enzymes of the clinical strains of Pseudomonas aeruginosa and the transconjugants of E. coli carrying the plasmids discovered earlier in P. aeruginosa. The study was performed with a modified microiodometric method for determination of the activity of beta-lactamases. According to the M. Richmond classification of beta-lactamases the enzymes detected in P. aeruginosa strains 4529, 5290 and 9902 may correspond to the 5th class, the enzymes of P. aeruginosa strain 8208 to the 2nd class and the beta-lactamases of the E. coli transconjugants to the 3rd class. Two different beta-lactamases were detected in P. aeruginosa strain 10294.  相似文献   
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The efficiency of cryopreservation of seeds of five rare and endangered species of temperate orchids belonging to Platanthera and Dactylorhiza genera followed by their asymbiotic culture in vitro, as well as of in vitro cultured D. fuchsii protocorms (specific stage of orchid embryo development after release from the seed coat) was investigated. Germination rates of seeds after their exposure to liquid nitrogen were species-depended and could be either higher or lower than in the unfrozen control. There was no significant difference between growth rates of protocorms of the same species obtained from seeds collected in various Russia regions and cultured for 5 months. After vitrification, 9% of D. fuchsii protocorms with a larger diameter of 1200 μm survived cryopreservation; however, their growth was retarded for three months when compared to control protocorms.  相似文献   
6.
The aim of this work was to study the influence of storage in liquid nitrogen on the viability of seeds of the hybrid orchid Bratonia and further development of its protocorms in vitro. Seeds were frozen in ampoules by direct immersion in liquid nitrogen and stored in the cryobank for a month. The germination rates of cryopreserved and control (nonfrozen) seeds did not differ and remained as high as 100%. The protocorms derived were cultured on the agar-solidified Murashige and Skoog nutrient medium (MS), half-strength MS and Knop media and also in Morel liquid medium. During the first 45 days of culturing, protocorms derived from cryopreserved seeds grew faster than control protocorms on the MS and half-strength MS media but, at longer culturing (496 days), the size of control protocorms was significantly larger. After 639 days of culturing, there was no difference in the amount of perished, budding, and newly formed protocorms obtained from cryopreserved and control seeds, except half-strength MS medium where the number of budding protocorms in the case of cryopreserved seeds was a little greater than in the control treatment. After seed cryopreservation, the frequency of budding and newly formed protocorms was greater on the agarized MS and in liquid Morel media. Cryopreservation had little effect on the subsequent growth of protocorms in vitro. The preferable nutrient media for culturing the protocorms have been suggested.  相似文献   
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Intensive transformation and sedimentation of suspended matter from riverine runoff occur in estuarine frontal zones. The mesozooplankton community plays an important role in these processes. In the Ob Estuary, the dominant copepods Limnocalanus macrurus and Senecella siberica form dense local aggregations, but only scarce data on the ecology of these species in the estuarine environment are available. We aimed at analyzing the main aspects of the ecology of the two species including their grazing impact on phytoplankton. The distribution (net tows), ingestion rates (gut fluorescence analysis), respiration and excretion rates (incubation experiments), diet composition, gonad development and size of the lipid sacs of these copepods in a high-gradient area of the Ob Estuary were studied during a cruise of the R/V Professor Stockman in September 2013. S. siberica predominantly inhabited the freshwater zone; L. macrurus was more abundant in the estuarine frontal zone. In L. macrurus, adult females and males dominated the population, the herbivorous feeding hardly met the metabolic demands, the specific lipid content was high, and the gonads were developed. In S. siberica, the fifth copepodite stage (CV) dominated. The feeding rate considerably exceeded the metabolic requirements, and the lipid content was variable. The gonads were undeveloped. The two species grazed one-fifth of the phytoplankton biomass and more than 100 % of primary production, with S. siberica responsible for the main part of the total grazing impact (up to 90 %). These results are discussed in connection with the hydrophysical parameters and phase of the population’s life cycle. The obtained results contribute to the knowledge about zooplankton ecology and the transformation of suspended matter in an estuarine high-gradient environment.  相似文献   
9.
The Ser/Thr protein kinase PINK1 phosphorylates the well‐folded, globular protein ubiquitin (Ub) at a relatively protected site, Ser65. We previously showed that Ser65 phosphorylation results in a conformational change in which Ub adopts a dynamic equilibrium between the known, common Ub conformation and a distinct, second conformation wherein the last β‐strand is retracted to extend the Ser65 loop and shorten the C‐terminal tail. We show using chemical exchange saturation transfer (CEST) nuclear magnetic resonance experiments that a similar, C‐terminally retracted (Ub‐CR) conformation also exists at low population in wild‐type Ub. Point mutations in the moving β5 and neighbouring β‐strands shift the Ub/Ub‐CR equilibrium. This enabled functional studies of the two states, and we show that while the Ub‐CR conformation is defective for conjugation, it demonstrates improved binding to PINK1 through its extended Ser65 loop, and is a superior PINK1 substrate. Together our data suggest that PINK1 utilises a lowly populated yet more suitable Ub‐CR conformation of Ub for efficient phosphorylation. Our findings could be relevant for many kinases that phosphorylate residues in folded protein domains.  相似文献   
10.

Background

The Evidence-Based Practice (EBP) Project has been investigating the implementation of evidence-based mental health practices (Assertive Community Treatment, Family Psychoeducation, Integrated Dual Diagnosis Treatment, Illness Management and Recovery, and Supported Employment) in state public mental health systems in the United States since 2001. To date, Project findings have yielded valuable insights into implementation strategy characteristics and effectiveness. This paper reports results of an effort to identify and classify state-level implementation activities and strategies employed across the eight states participating in the Project.

Methods

Content analysis and Greenhalgh et al's (2004) definition of innovation were used to identify and classify state-level activities employed during three phases of EBP implementation: Pre-Implementation, Initial Implementation and Sustainability Planning. Activities were coded from site visit reports created from documents and notes from key informant interviews conducted during two periods, Fall 2002 – Spring 2003, and Spring 2004. Frequency counts and rank-order analyses were used to examine patterns of implementation activities and strategies employed across the three phases of implementation.

Results

One hundred and six discreet implementation activities and strategies were identified as innovative and were classified into five categories: 1) state infrastructure building and commitment, 2) stakeholder relationship building and communications, 3) financing, 4) continuous quality management, and 5) service delivery practices and training. Implementation activities from different categories were employed at different phases of implementation.

Conclusion

Insights into effective strategies for implementing EBPs in mental health and other health sectors require qualitative and quantitative research that seeks to: a) empirically test the effects of tools and methods used to implement EBPs, and b) establish a stronger evidence-base from which to plan, implement and sustain such efforts. This paper offers a classification scheme and list of innovative implementation activities and strategies. The classification scheme offers potential value for future studies that seek to assess the effects of various implementation processes, and helps establish widely accepted standards and criteria that can be used to assess the value of innovative activities and strategies.  相似文献   
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