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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.
On the basis of spectral analysis of prolonged realizations (hundreds of seconds) of electrosubcorticograms of the amygdalar complexes of three dogs, the effect of increase in power of amygdalar rhythmic activity was found, at the change of motivation level in conditions of dominance of alimentary or defensive motivation independently of its kind. Resonance characteristics of the system responsible for the generation of the given rhythm remain unchanged; this allows to explain the increase of the spectral peak by the rise of the inflow of afferent impulse activity to the amygdala. At presence of competitive motivations no summation of their influences is observed; a more complex effect on the rhythm arises in the amygdala.  相似文献   
3.
Evaluation of the effects of radioactive contamination on human populations is important for an understanding of the present and future risk for human health, including the genetic risk. This review centers on the results of population monitoring of developmental anomalies among human embryos and congenital malformations among newborn in the Republic of Belarus before and after Chemobyl accident. The data revealed that the incidences of developmental anomalies and congenital malformation from the mostly radionuclide-contaminated rural regions of Belarus reliably exceed the indices in control areas.  相似文献   
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5.
Human myocardium proteins synthesized in the course of heart muscle development have been analyzed by two-dimensional electrophoresis. The quantitative change was found in representation of the main retractable proteins in the course of the heart muscle formation (the light myosin chains, tropomyosin, etc.). Four polymorphous variants of myocardium proteins were found, one of which is, possibly connected with the defect in heart development.  相似文献   
6.
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   
7.

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   
8.
The frequencies of three alleles, CCR5delta32, CCR2-64I, and SDF1 3'A, known to decrease the risk of AIDS onset and the rate of the disease progression in HIV-infected individuals were determined in three native population samples from Russia, Ukraine, and Belarus. The frequencies of the alleles were 0.15, 0.12, 0.21; 0.12, 0.07, 0.20; and 0.12, 0.08, 0.26 for Russians, Ukrainians, and Belarussians, respectively. The proportion of the individuals without any of three protective alleles among Russians, Ukrainians, and Belarussians constituted 49, 65, and 61%, respectively. The genotype frequencies for the three loci studied were in Hardy-Weinberg equilibrium. Based on the three-locus genotype frequencies, the hazard ratios (relative hazards, RH) of AIDS onset in HIV-infected individuals in each sample were calculated as ranging from 0.79 to 0.88. In the samples of Eastern Slavs analyzed the estimated frequencies of the AIDS-protective alleles tested, as well as the frequencies of the corresponding genotypes and the relative hazards of AIDS onset were within the range of these parameters for the other European populations. The data on the allele frequencies and the relative hazard values in Russians, Ukrainians and Belarussians can be used as the predictors of AIDS onset and progression rate in HIV-1-infected individuals from the populations studied.  相似文献   
9.
The effect of ketocef or cefuroxim, a new cephalosporin antibiotic, on the immune system was studied on mice. The repeated use of the drug for 10 days a dose of 30 mg/kg injected intramuscularly did not result in suppression of the immune status. The number of the rosette forming cells of the thymus and spleen did not change. The production of hemolysin as shown by the number of the antibody forming cells somewhat increased, when the animals were immunized with the sheep red blood cells. A certain decrease in the intensity of the anaphylactic reaction was observed in sensitization of the animals with bovine serum.  相似文献   
10.
Clinical efficacy and effect of cefuroxime, claforan and pentrexyl used endolymphatically were studied in 85 patients with acute abscess forming and persisting pneumonia. Previous routine antibiotic therapy in these patients was little effective. Administration of the antibiotics into the peripheral lymph nodes provided blocking of the lymphagenic pathway for the infection due to high levels in the lymphatic system. Endolymphatic use of cefuroxime and claforan resulted in a significant improvement of the functions of the T- and B-immunity systems and the indices of natural resistance. The levels of the autoimmune reactions and sensitization to the bacterial antigens decreased. Endolymphatic use of cefuroxime and claforan once every 3 days provided recovery of 9 2.8 per cent of the patients, the treatment periods being decreased 2.5--3 times. Intravenous administration of the drugs according to the routine schemes, endolymphatic use of pentrexyl (5 g once every 3 days) and endolymphatic administration of cefuroxime in a single dose followed by intravenous therapy was less effective. The efficacy of pentrexyl increased, when it was used endolymphatically in combination with lysozyme. Endolymphatic use of claforan in doses of 2--3 g once every 3 days (3--4 infusions during the treatment course) was most effective.  相似文献   
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