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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.
The data obtained revealed the maintenance of basophiles; monocytes and large granular lymphocytes were higher in the skin then in the venous blood. The level of eosinophiles and lymphocytes were lower in the skin. Concentrations of the polymorphic leucocytes were equal in the skin and in the blood.  相似文献   
3.
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   
4.

Background

A public that is an informed partner in clinical research is important for ethical, methodological, and operational reasons. There are indications that the public is unaware or misinformed, and not sufficiently engaged in clinical research but studies on the topic are lacking. PARTAKE – Public Awareness of Research for Therapeutic Advancements through Knowledge and Empowerment is a program aimed at increasing public awareness and partnership in clinical research. The PARTAKE Survey is a component of the program.

Objective

To study public knowledge and perceptions of clinical research.

Methods

A 40-item questionnaire combining multiple-choice and open-ended questions was administered to 175 English- or Hindi-speaking individuals in 8 public locations representing various socioeconomic strata in New Delhi, India.

Results

Interviewees were 18–84 old (mean: 39.6, SD±16.6), 23.6% female, 68.6% employed, 7.3% illiterate, 26.3% had heard of research, 2.9% had participated and 58.9% expressed willingness to participate in clinical research. The following perceptions were reported (% true/% false/% not aware): ‘research benefits society’ (94.1%/3.5%/2.3%), ‘the government protects against unethical clinical research’ (56.7%/26.3%/16.9%), ‘research hospitals provide better care’ (67.2%/8.7%/23.9%), ‘confidentiality is adequately protected’ (54.1%/12.3%/33.5%), ‘participation in research is voluntary’ (85.3%/5.8%/8.7%); ‘participants treated like ‘guinea pigs’’ (20.7%/53.2%/26.0%), and ‘compensation for participation is adequate’ (24.7%/12.9%/62.3%).

Conclusions

Results suggest the Indian public is aware of some key features of clinical research (e.g., purpose, value, voluntary nature of participation), and supports clinical research in general but is unaware of other key features (e.g., compensation, confidentiality, protection of human participants) and exhibits some distrust in the conduct and reporting of clinical trials. Larger, cross-cultural surveys are required to inform educational programs addressing these issues.  相似文献   
5.
Bacterial suspensions of cultures (10(7) PFU) of pathogenic Staphylococcus, vulgar Proteus and pyocyanic bacterium are resistant to 2.9-46.87 mg per disc of iodopyron in 100% of cases. Sensitivity of 32 and 100% of cultures of pyocyanic bacteria (of 25 under study) being in the suspension (10(5) PFU) to 11.71 and 23.43-9.375 mg of idopyron, respectively, in a hole has been established. To determine sensitivity of pyocyanic bacteria to iodopyron it is suggested to use the procedure of adding of 11.71 mg of the preparation (water solution) to the holes in MPA.  相似文献   
6.
Differential UV spectroscopy and thermal denaturation were used to study the Mg2+ ion effect on the conformational equilibrium in poly A · 2 poly U (A2U) and poly A · poly U (AU) solutions at low (0.01 M Na+) and high (0.1 M Na+) ionic strengths. Four complete phase diagrams were obtained for Mg2+–polynucleotide complexes in ranges of temperatures 20–96 °C and concentrations (10−5–10−2) M Mg2+. Three of them have a ‘critical’ point at which the type of the conformational transition changes. The value of the ‘critical’ concentration ([Mgt2+]cr=(4.5±1.0)×10−5 M) is nearly independent of the initial conformation of polynucleotides (AU, A2U) and of Na+ contents in the solution. Such a value is observed for Ni2+ ions too. The phase diagram of the (A2U+Mg2+) complex with 0.01 M Na+ has no ‘critical’ point: temperatures of (3→2) and (2→1) transitions increase in the whole Mg2+ range. In (AU+Mg2+) phase diagram at 0.01 M Na+ the temperature interval in which triple helices are formed and destroyed is several times larger than at 0.1 M Na+. Using the ligand theory, a qualitative thermodynamic analysis of the phase diagrams was performed.  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.
9.
This review analyzes data on the biological role of 3-hydroxysteroid dehydrogenase (3-HSD) in animal and human tissues and describes its main characteristics, mechanism of action, and regulation of activity. Based on published data, a scheme for the actions of androgen, progestin, and glucocorticoids involving the participation of 3-HSD is proposed. According to this scheme, in the mechanism of steroid action 3-HSD not only regulates the concentration of the main effector androgen, 5-dihydrotestosterone, in target cells, but also switches androgen, progestin, and glucocorticosteroid genomic activity to non-genomic activity.  相似文献   
10.
It is found that acute ethanol intoxication is accompanied by a decrease in the ascorbic acid content in the brain, liver and kidneys. The content of dehydroascorbic acid in kidneys in this case increases and in the brain tends to decrease. The chronic alcohol intoxication of rats has an opposite (as compared to the acute intoxication) effect on changes in the content of ascorbic and dehydroascorbic acids in the studied organs. People with chronic alcohol intoxication have the lower content of ascorbic acid in blood plasma and the higher content in erythrocytes, the content of dehydroascorbic acid being increased.  相似文献   
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