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Acute effects of ghrelin administration on glucose and lipid metabolism   总被引:11,自引:0,他引:11  
CONTEXT: Ghrelin infusion increases plasma glucose and nonesterified fatty acids, but it is uncertain whether this is secondary to the concomitant release of GH. OBJECTIVE: Our objective was to study direct effects of ghrelin on substrate metabolism. DESIGN: This was a randomized, single-blind, placebo-controlled two-period crossover study. SETTING: The study was performed in a university clinical research laboratory. PARTICIPANTS: Eight healthy men aged 27.2 +/- 0.9 yr with a body mass index of 23.4 +/- 0.5 kg/m(2) were included in the study. INTERVENTION: Subjects received infusion of ghrelin (5 pmol x kg(-1) x min(-1)) or placebo for 5 h together with a pancreatic clamp (somatostatin 330 microg x h(-1), insulin 0.1 mU x kg(-1) x min(-1), GH 2 ng x kg(-1) x min(-1), and glucagon 0.5 ng.kg(-1) x min(-1)). A hyperinsulinemic (0.6 mU x kg(-1) x min(-1)) euglycemic clamp was performed during the final 2 h of each infusion. RESULTS: Basal and insulin-stimulated glucose disposal decreased with ghrelin [basal: 1.9 +/- 0.1 (ghrelin) vs. 2.3 +/- 0.1 mg x kg(-1) x min(-1), P = 0.03; clamp: 3.9 +/- 0.6 (ghrelin) vs. 6.1 +/- 0.5 mg x kg(-1) x min(-1), P = 0.02], whereas endogenous glucose production was similar. Glucose infusion rate during the clamp was reduced by ghrelin [4.0 +/- 0.7 (ghrelin) vs. 6.9 +/- 0.9 mg.kg(-1) x min(-1); P = 0.007], whereas nonesterified fatty acid flux increased [131 +/- 26 (ghrelin) vs. 69 +/- 5 micromol/min; P = 0.048] in the basal period. Regional lipolysis (skeletal muscle, sc fat) increased insignificantly with ghrelin infusion. Energy expenditure during the clamp decreased after ghrelin infusion [1539 +/- 28 (ghrelin) vs. 1608 +/- 32 kcal/24 h; P = 0.048], but the respiratory quotient did not differ. Minor but significant elevations in serum levels of GH and cortisol were observed after ghrelin infusion. CONCLUSIONS: Administration of exogenous ghrelin causes insulin resistance in muscle and stimulates lipolysis; these effects are likely to be direct, although a small contribution of GH and cortisol cannot be excluded.  相似文献   
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Surface treatment of medical devices may be a way of avoiding the need for replacement of these devices and the comorbidities associated with infection. The aim of this study was to evaluate whether pre- and postcontamination washing of 2 prostheses with different textures can decrease bacterial contamination.The following microorganisms were evaluated: Staphylococcus aureus, Staphylococcus epidermidis, Proteus mirabilis and Enterococcus faecalis. Silicone and expanded polytetrafluoroethylene vascular prostheses were used and divided into 3 groups: prostheses contaminated; prostheses contaminated and treated before contamination; and prostheses contaminated and treated after contamination. Treatments were performed with antibiotic solution, chlorhexidine and lidocaine. After one week of incubation, the prostheses were sown in culture medium, which was incubated for 48 hours. The area of colony formation was evaluated by fractal dimension, an image analysis tool.The antibiotic solution inhibited the growth of S epidermidis and chlorhexidine decrease in 53% the colonization density for S aureus in for both prostheses in the pre-washing. In postcontamination washing, the antibiotic solution inhibited the growth of all bacteria evaluated; there was a 60% decrease in the colonization density of S aureus and absence of colonization for E faecalis with chlorhexidine; and lidocaine inhibited the growth of S aureus in both prostheses.Antibiotic solution showed the highest efficiency in inhibiting bacterial growth, especially for S epidermidis, in both washings. Lidocaine was able to reduce colonization by S aureus in post-contamination washing, showing that it can be used as an alternative adjuvant treatment in these cases.  相似文献   
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PURPOSE

The pragmatic utility method of concept analysis was used to explore the usefulness of the concept self‐care self‐efficacy.

DATA SOURCES

Empirical studies across disciplines published between 1996 and 2015 were used as data.

DATA SYNTHESIS

A data matrix was developed. Analytical questions and responses were derived from the data to understand patterns, develop new knowledge and achieve synthesis.

CONCLUSION

Usefulness of the concept is contingent on how it is defined and measured. Self‐care self‐efficacy is associated with performance of self‐care activities and positive health outcomes in diverse populations.

IMPLICATIONS

Research can guide development of targeted interventions to increase patients' self‐care self‐efficacy, thus reducing costs, and assisting people to achieve optimal health.  相似文献   
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Attention to health care quality and safety has increased dramatically. The internal focus of an organization is not without influence from external policy and research findings. Compared with other specialties, efforts to align and advance rehabilitation research, practice, and policy using electronic health record data are in the early stages. This special communication defines quality, applies the dimensions of quality to rehabilitation, and illustrates the feasibility and utility of electronic health record data for research on rehabilitation care quality and outcomes. Using data generated at the point of care provides the greatest opportunity for improving the quality of health care, producing generalizable evidence to inform policy and practice, and ultimately benefiting the health of the populations served.  相似文献   
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Purpose

This review article provides a detailed discussion of studies in which microextraction techniques are applied for the determination of new psychoactive substances (NPS) in biological samples. Definitions and classifications of NPS are highlighted as well as the fundamentals of the microextraction techniques used in their analyses.

Methods

A complete literature search was carried out with PubMed, Scopus and the World Wide Web using relevant keywords, e.g., NPS, microextraction and biological fluids.

Results

The determinations of NPS in biological samples remain a challenge for analytical laboratories due to its wide diversity of compounds. The utilization of microextraction techniques in this context is still not many. However, the 96 deep well plate for microextraction and microextraction by packed sorbent (MEPS) can be highlighted as the most explored configurations. Microextraction approaches have the potential to be further improved and optimized to provide rapid and low-cost analyses with reliable results.

Conclusions

There is a wide scope of microextraction techniques to be explored in the field of toxicology and NPS determinations. These techniques are compatible with recent trends of automation and miniaturization, which can enable a straightforward workflow for NPS analyses.

  相似文献   
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