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991.
Comparative in vitro efficacies and antimicrobial durabilities of novel antimicrobial central venous catheters 下载免费PDF全文
Hanna H Bahna P Reitzel R Dvorak T Chaiban G Hachem R Raad I 《Antimicrobial agents and chemotherapy》2006,50(10):3283-3288
We investigated the efficacies and durability of novel antimicrobial central venous catheters (CVCs) in preventing the adherence of microbial organisms to the surfaces of the CVCs. Novel antimicrobial CVCs investigated in this in vitro study were impregnated with antibiotics (minocycline and rifampin), with Oligon agent (silver, platinum, and carbon black), with approved antiseptics (chlorhexidine and silver sulfadiazine), or with a novel antiseptic agent, gendine, which contains gentian violet and chlorhexidine. When tested against methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa, gendine-coated CVC segments provided protection against bacterial adherence significantly more than all other types of tested CVCs (P < 0.05). Gendine-coated CVCs also provided better protection against Candida albicans and Candida parapsilosis than CVCs impregnated with antibiotics or with silver, platinum, and carbon (P < 0.02). After 28 days of being soaked in serum, the CVCs impregnated with chlorhexidine and silver sulfadiazine and the CVCs impregnated with silver, platinum, and carbon had lost antimicrobial activity against MRSA, P. aeruginosa, and C. parapsilosis, and the CVCs impregnated with minocycline and rifampin had lost activity against P. aeruginosa and C. parapsilosis. The CVCs impregnated with gendine maintained antimicrobial activities against MRSA, P. aeruginosa, and C. parapsilosis after 28 days of being soaked in serum. Central venous catheters impregnated with the novel investigational antiseptic gendine showed in vitro efficacy and provided protection against bacterial adherence more than other approved novel antimicrobial-coated CVCs. 相似文献
992.
OBJECTIVES: To compare the analysis of different forms of intact albumin in urine from healthy volunteers. To determine contamination by common non-albumin proteins on HPLC analysis of urinary albumin and of purified immuno-unreactive albumin. DESIGN AND METHODS: Overnight urine samples collected from healthy volunteers were analysed for total albumin (immunoreactive plus immuno-unreactive) by HPLC and densitometry following native PAGE separation and for immunoreactive albumin by RIA. The contamination by non-albumin proteins of the HPLC analysis of urinary albumin and of immuno-unreactive albumin preparations was determined by ELISA. Immuno-unreactive albumin was tested for Co2+-binding capacity. RESULTS AND CONCLUSIONS: HPLC analysis of healthy urine generates higher ACR values than immunological methods due to the presence of immuno-unreactive albumin. Immuno-unreactive albumin cannot be accounted for by the non-albumin urinary proteins tested. Isolated immuno-unreactive albumin is not recognised by antibodies to common urinary proteins or by an array of anti-albumin antibodies and behaves like serum albumin in terms of HPLC elution, native PAGE migration, and cobalt ion binding. 相似文献
993.
OBJECTIVES: To test reproducibility, speed and cost of testing for factor V Leiden and FII 20210G>A in our practice. DESIGN AND METHODS: We compared conformity, reproducibility, speed and cost using the Light Cycler (LC) and PCR-RFLP. RESULTS: There was 100% conformity and reproducibility. LC was faster but 23% more expensive per sample. When equipment depreciation and patient expenses are added, LC testing becomes cheaper. CONCLUSION: In our practice, LC provides fast, reproducible and cost-effective results. 相似文献
994.
Reynolds T Cole E 《Nursing standard (Royal College of Nursing (Great Britain) : 1987)》2006,20(21):55-64 quiz 66, 68
This article provides an overview of the assessment and management of the common types of acute wound that frequently present to accident and emergency departments, minor injury units and walk-in centres, and which require closure. 相似文献
995.
Greig C Spreckley K Aspinwall R Gillaspy E Grant M Ollier W John S Doherty M Wallis G 《Annals of the rheumatic diseases》2006,65(9):1131-1138
OBJECTIVE: To identify susceptibility loci for nodal osteoarthritis. METHODS: A genome screen at an average marker spacing of 9.29 cM was carried out on 558 people from 202 families, of whom 491 had nodal osteoarthritis. All genotyped people were graded for the incidence and severity of distal interphalangeal (DIP) nodes, and radiographs from 354 people were graded for joint-space narrowing (JSN) and osteophytes (OSTs). Age-regressed indices for DIP nodes, JSN and OSTs were calculated using these phenotypic data. Affected sibling pair (ASP) and quantitative trait analyses were carried out using MERLIN. RESULTS: The data analysis identified suggestive linkage to loci on chromosomes 3 (for JSN and OST), 4 (for JSN), 8 (for DIP), 11 (for radiographic osteoarthritis) and 16 (for JSN). Both the ASP and quantitative analyses identified the loci on chromosomes 4 and 11. The loci on chromosomes 3 and 16 overlap with those previously identified for large-joint osteoarthritis. Of the loci identified by the quantitative analyses with the logarithm of the odds of linkage >1.5, two were linked to more than one trait, whereas nine were linked to single traits: one for DIP, six for JSN and two for OST. CONCLUSION: The ASP and quantitative analyses of the cohort with nodal osteoarthritis suggest that multiple susceptibility loci for osteoarthritis influence the traits, which combine to form the osteoarthritis phenotype, and that these loci may not act exclusively on the joints of the hand. 相似文献
996.
997.
BACKGROUND & AIMS: Airways are most vulnerable to aspiration during sleep. Esophago-upper esophageal sphincter (UES) contractile reflex (EUCR) and secondary peristalsis (2P) have been proposed to protect the airway by reflexively contracting the UES and clearing the esophagus of refluxate, respectively. Our aim was to study EUCR and 2P elicitation in "awake" state, stage II, slow-wave (stage III/IV), and rapid eye movement (REM) sleep. METHODS: Thirteen healthy volunteers were studied in the supine position using concurrent UES and esophageal manometry and polysomnography. Threshold volume (Tvol) to trigger EUCR and 2P and changes in sleep stages were recorded during injection of 2.7 mL/min water into the proximal esophagus after sleep stages were confirmed. RESULTS: UES pressure progressively declined with deeper stages of sleep. Tvol for EUCR and 2P elicitation was not significantly different between the stage II and "awake" state (EUCR: 4.0 +/- 1.8 mL vs 6.1 +/- 3.6 mL stage II; 2P: 5.8 +/- 2.2 mL vs 8.0 +/- 4.0 mL stage II). Tvol for EUCR and 2P elicitation during REM sleep were significantly lower than during the stage II and "awake" state (REM EUCR: 2.2 +/- 1.1 mL; 2P: 3.5 +/- 1.2 mL). Arousal and cough preempted development of EUCR and 2P during slow-wave sleep. CONCLUSIONS: (1) EUCR/2P can be elicited in stage II and REM but is preempted by arousal in slow-wave sleep. (2) Tvol for EUCR/2P elicitation is significantly lower in REM, compared with the stage II and "awake" state, suggesting a heightened sensitivity of these reflexes during REM sleep. (3) Although UES pressure progressively declines with deeper stages of sleep, it can still reflexively contract during REM sleep, despite generalized hypotonia. 相似文献
998.
Morishima C Polyak SJ Ray R Doherty MC Di Bisceglie AM Malet PF Bonkovsky HL Sullivan DG Gretch DR Rothman AL Koziel MJ Lindsay KL;Hepatitis C Antiviral Long-Term Treatment Against Cirrhosis Trial Group 《The Journal of infectious diseases》2006,193(7):931-940
Pretreatment hepatitis C virus (HCV)-specific lymphoproliferative (LP) responses, neutralizing antibody (NA) responses, intrahepatic cytotoxic T lymphocyte (CTL) responses, and HCV quasi-species (QS) diversity and complexity were examined in patients with advanced hepatic fibrosis (Ishak fibrosis score of > or = 3) and prior nonresponse to interferon (IFN)- alpha therapy who were enrolled in the initial phase of the Hepatitis C Antiviral Long-Term Treatment against Cirrhosis Trial. Positive baseline HCV E1- and/or E2-specific NA responses (P = .01) and higher baseline HCV QS diversity (P = .01) were more commonly found in patients who did not become sustained virologic responders (SVRs) at week 72 (W72) than they were in those who did. No patients with positive results for both the LP and NA assays achieved a sustained virologic response. Multiple logistic regression analysis revealed that, when the presence of cirrhosis, prior ribavirin therapy, genotype 1 infection, log serum HCV RNA level, and receipt of >80% of the prescribed medication were controlled for, a sustained virologic response (W72) was negatively correlated with positive baseline LP assay results (P = .02) and with 1 or more positive assays (LP, NA, or CTL) (P = .02). No differences were noted in baseline intrahepatic CTL activity between SVRs and non-SVRs. Thus, in patients with advanced hepatic fibrosis due to HCV infection, pretreatment HCV-specific immune responses and increased QS variability appear to hinder viral clearance by pegylated IFN- alpha 2a and ribavirin combination therapy. 相似文献
999.
Kedzierska K Venturi V Field K Davenport MP Turner SJ Doherty PC 《Proceedings of the National Academy of Sciences of the United States of America》2006,103(24):9184-9189
Single-cell analysis of endogenous, primary CD8(+) T cell responses to the influenza D(b)NP(366) and D(b)PA(224) epitopes indicates that prominent clonotypes bearing "public" or "shared" T cell receptors (TCRs) subset early into CD62L(hi) and CD62L(lo) populations. The CD62L(lo) effectors divide more and are rapidly eliminated during the contraction phase, whereas stable CD62L(hi) memory populations persist in the long-term. Reflecting the high frequency of small CD62L(hi) clones expressing "private" TCRs, the TCR diversity range per mouse is generally two times higher within the CD62L(hi)CD8(+)D(b)NP(366)(+) set (1.6 times higher for CD62L(hi)CD8(+)D(b)PA(224)(+)) from 8 to >180 days after antigen challenge. Memory CD8(+)CD62L(hi) T cell precursors thus segregate from the outset into populations expressing "best-fit" and "suboptimal" TCR characteristics, with this pattern being maintained stably thereafter. Hence, our analysis suggests that early establishment of influenza-specific memory within the CD8(+)CD62L(hi) subset preserves clonal diversity and prevents "overdominance" by a few public, or shared, clones. 相似文献
1000.
AIM: This paper reports an evaluation of nursing and midwifery research and development activity in Northern Ireland. BACKGROUND: Research and development is integral to the quality of patient care. Nurses and midwives have an important contribution to make and, whilst the professional landscape has changed significantly, with improved funding and productivity, there remains much room for improvement. To advance this agenda it is necessary to evaluate progress across the spectrum of research and development activity. The policy literature gives examples of the methods by which this can be achieved, but there is less evidence about evaluation criteria, or the methods by which research and development progress is assessed at organizational, national and international levels. METHOD: A comprehensive analysis of the literature was undertaken to develop a 'Research and Development Best Practice Framework'. This was then used as the basis for structured interviews with 32 organizational leads for three main stakeholder groups: health and care providers (n = 20), education providers (n = 7) and funders of research and development (n = 5). Data collection was from March to November 2004. FINDINGS: Despite general recognition of its value, only a minority of organizations had an up-to-date corporate strategy that included nursing and midwifery research and development. There was considerable variability in the systems, support structures, capacity and productivity of nurses and midwives throughout these organizations. In most, no-one had sole responsibility for leading the professional research and development agenda but, where such leadership was in place, improved outcomes were apparent. Building effective partnerships for research and development and forward planning through developing an organizational strategy were also key indicators of success. CONCLUSION: Our findings confirm progress, but also reinforce the need to develop a clear vision, enhance leadership potential and forge effective partnerships to advance the research and development agenda in nursing and midwifery. 相似文献