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OBJECTIVES: To systematically collect and analyse diverse definitions of 'evidence' in both health and social sciences, and help users to correctly use the term 'evidence' and rethink what is the definition of 'evidence' in scientific research. DESIGN: Scoping review. METHODS: Definitions of evidence in the health sciences and social sciences were included. We have excluded the definition of evidence applied in the legal field, abstracts without full text, documents not published in either Chinese or English and so on. We established a multidisciplinary working group and systematically searched five electronic databases including Medline, Web of Science, EBSCO, the Chinese Social Sciences Citation Index and the Chinese Science Citation Database from their inception to 26 February 2022. We also searched websites and reviewed the reference lists of the identified studies. Six reviewers working in pairs, independently, selected studies according to the inclusion and exclusion criteria, and extracted information. Any differences were discussed in pairs, and if there was disagreement, it was resolved via discussion or with the help of a third reviewer. Reviewers extracted document characteristics, the original content for the definitions of 'evidence', assessed definitions as either intensional or extensional, and any citations for the given definition. RESULTS: Forty-nine documents were finally included after screening, and 68 definitions were obtained. After excluding duplicates, a total of 54 different definitions of 'evidence' were identified. There were 42 intensional definitions and 12 extensional definitions. The top three definiens were 'information', 'fact' and 'research/study'. The definition of 'evidence' differed between health and social sciences. The term 'research' appeared most frequently in the definitions. CONCLUSIONS: The definition of 'evidence' has gradually attracted the attention of many scholars and decision-makers in health and social sciences. Nevertheless, there is no widely recognised and accepted definition in scientific research. Given the wide use of the term, we need to think about whether, or under what circumstances, a standardised, clear, meaningful and widely applicable definition of 'evidence' might be helpful.
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A phosphorus containing acrylate monomer has been constructed from isosorbide, a renewable biomaterial. Treatment of isosorbide with diphenylchlorophosphate generates a mixture of phosphorus esters from which exo-5-(diphenylphosphato)isosorbide-2-endo-ol may be isolated using column chromatography. Conversion of the alcohol to the corresponding acrylate by treatment with acroyl chloride provides a reactive acryloyl monomer containing a diphenylphosphato unit. Copolymerization of this monomer, at levels to provide 1% or 2% phosphorus incorporation, with styrene generates a polymer with substantially diminished flammability compared to that for styrene homopolymer.
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Extensive atomic force and electron microscopy reveal a new, generic DNA-colloid complex with a fixed number of DNA bases per colloid. The fiber shaped complex is stable in the presence of excess colloids in the solution. As more DNA is added to the solution and the ratio between colloids and DNA approaches the fiber's stoichiometry, the system undergoes a sharp coagulation transition. The system is restabilized at even higher DNA concentrations through localization of small colloid clusters on extensive DNA networks.
Assuntos
DNA/química , Coloide de Ouro/química , Bacteriófago lambda/química , DNA Viral/química , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Eletricidade EstáticaRESUMO
OBJECTIVE: To explore the possibilty of creating a temporary sclerotomy using a 26-gauge needle and sustaining its patency by injectiong 0.1 mL of 0.1 mg/mL of mitomycin C (MMC). ANIMALS AND METHODS: Twenty-four New Zealand white rabbits were randomized into 3 groups. In the test group, puncture was performed using 26-gauge needle penetrating the anterior chamber at the limbus, and 0.1 mg/mL MMC were injected subconjunctivally. In the control group, a puncture was performed in the same fashion and in the MMC group, MMC only was injected subconjunctivally. Intraocular pressure (IOP) was measured prior to surgery and at days 1, 3, 7, 10, 14, 21, and 28. RESULTS: The mean intraocular pressure in eyes that underwent puncture with application of MMC was significantly lower than the IOP in the eye at all measurements up to and including day 21. In the puncture group, pressure was significantly lower than in the fellow eye only at day 3. No significant pressure reduction was observed at any measurement interval in eyes treated with MMC only. CONCLUSION: This simple technique of subconjunctival puncture of the limbus combined with application of MMC was effective in lowering IOP in rabbits. This may serve to attain a temporary filter in patients who need strict short-term pressure control.
Assuntos
Mitomicina/farmacologia , Agulhas , Procedimentos Cirúrgicos Oftalmológicos/instrumentação , Procedimentos Cirúrgicos Oftalmológicos/métodos , Punções , Esclera/cirurgia , Animais , Túnica Conjuntiva , Olho/patologia , Injeções , Pressão Intraocular/efeitos dos fármacos , Coelhos , Fatores de TempoRESUMO
The intestinal trans-epithelial elimination of moxifloxacin was measured in the jejunum, ileum, caecum and in the bile in a rabbit model. Over a 120 min period following a single parenteral administration of moxifloxacin 15 mg/kg, peak serum concentration was 3.1 (+/- 1.1) mg/L. The elimination constants were: 0.019 (+/- 0. 017) microg/cm(2)/min, 0.011 (+/- 0.014) microg/cm(2)/min and 0.002 (+/- 0.002) microg/cm(2)/min in the jejunum, ileum and caecum, respectively. Per loop, over 120 min, the respective eliminated quantities were: 9.59 (+/- 9.37) microg, 8.26 (+/- 6.74) microg and 1.92 (+/- 1.86) microg. Biliary moxifloxacin concentrations varied between 1.30 and 5.16 mg/L and exceeded serum levels from 45 min onwards. Intestinal concentrations paralleled serum moxifloxacin levels. Altogether, approximately 4.5% of the moxifloxacin dose was eliminated trans-epithelially in the digestive tract over the 120 min experimental period.
Assuntos
Anti-Infecciosos/farmacocinética , Compostos Aza , Fluoroquinolonas , Mucosa Intestinal/metabolismo , Quinolinas , Animais , Anti-Infecciosos/administração & dosagem , Área Sob a Curva , Bacillus subtilis/efeitos dos fármacos , Bile/metabolismo , Bioensaio , Epitélio/metabolismo , Injeções Intravenosas , Fígado/metabolismo , Masculino , Moxifloxacina , CoelhosAssuntos
Anti-Infecciosos/farmacologia , Compostos Aza , Escherichia coli/efeitos dos fármacos , Fluoroquinolonas , Quinolinas , Staphylococcus aureus/efeitos dos fármacos , Streptococcus pneumoniae/efeitos dos fármacos , Albuminas/efeitos adversos , Ciprofloxacina/farmacologia , Infecções por Escherichia coli/tratamento farmacológico , Globulinas/efeitos adversos , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Humanos , Testes de Sensibilidade Microbiana , Moxifloxacina , Naftiridinas/farmacologia , Infecções Pneumocócicas/tratamento farmacológico , Infecções Estafilocócicas/tratamento farmacológico , Supuração/patologiaRESUMO
Recent research in the field of nanometre-scale electronics has focused on two fundamental issues: the operating principles of small-scale devices, and schemes that lead to their realization and eventual integration into useful circuits. Experimental studies on molecular to submicrometre quantum dots and on the electrical transport in carbon nanotubes have confirmed theoretical predictions of an increasing role for charging effects as the device size diminishes. Nevertheless, the construction of nanometre-scale circuits from such devices remains problematic, largely owing to the difficulties of achieving inter-element wiring and electrical interfacing to macroscopic electrodes. The use of molecular recognition processes and the self-assembly of molecules into supramolecular structures might help overcome these difficulties. In this context, DNA has the appropriate molecular-recognition and mechanical properties, but poor electrical characteristics prevent its direct use in electrical circuits. Here we describe a two-step procedure that may allow the application of DNA to the construction of functional circuits. In our scheme, hybridization of the DNA molecule with surface-bound oligonucleotides is first used to stretch it between two gold electrodes; the DNA molecule is then used as a template for the vectorial growth of a 12 microm long, 100 nm wide conductive silver wire. The experiment confirms that the recognition capabilities of DNA can be exploited for the targeted attachment of functional wires.