Science Citation (science + citation)

Distribution by Scientific Domains

Terms modified by Science Citation

  • science citation index

  • Selected Abstracts

    Meta-analysis: octreotide prevents post-ERCP pancreatitis, but only at sufficient doses

    Y. ZHANG
    Summary Background, Effects of octreotide on post-endoscopic retrograde cholangiopancreatography pancreatitis have been studied in many clinical trials. These trials have yielded inconclusive results. Results of more recent studies using larger doses, however, seem to be more optimistic. Aim, To examine effects of octreotide at different doses on PEP. Methods, A comprehensive search of relevant databases, including Medline, Embase, the Cochrane Controlled Trials Register, the Cochrane Library and Science Citation Index yielded 18 randomized controlled trials (RCTs). Trials were divided into two groups according to the total dosage of octreotide: <0.5 mg (OCT1), ,0.5 mg (OCT2). The rate of PEP was analysed using a fixed effect model. Results, At doses of ,0.5 mg, octreotide reduced the rate of PEP. In the OCT2 group, analysis revealed a statistically significant difference on PEP between the octreotide group and the controls (3.4% vs. 7.5%, pooled OR = 0.45; 95% CI: 0.28,0.73; P = 0.001, NNT = 25). In the OCT1 group, the rate of PEP was similar between patients receiving octreotide and the controls (7.2% vs. 6.0%, pooled OR = 1.23; 95% CI: 0.80,1.91; P = 0.35). Conclusion, Octreotide is effective in preventing PEP, but only at sufficient doses (,0.5 mg). [source]

    Meta-analysis: the efficacy and safety of certolizumab pegol in Crohn's disease

    L.-M. SHAO
    Summary Background, Certolizumab pegol is the third anti-TNF-, agent approved by the Food and Drug Administration of the United States. Aim, To provide a comprehensive up-to-date review of the efficacy and safety of certolizumab in Crohn's disease (CD). Methods, Electronic databases, including PubMed, EMBASE, the Cochrane library and the Science Citation Index, were searched to retrieve relevant trials. In addition, meeting abstracts and the reference lists of retrieved articles were reviewed for further relevant studies. Results, Three trials, enrolling a total of 1040 patients, are included in the meta-analysis to evaluate the short-term efficacy of certolizumab, which is effective for rapid induction and long-term maintenance of clinical response or remission and can improve quality of life in patients with Crohn's disease. Certolizumab is also effective for patients who have lost response to infliximab. However, its efficacy in infliximab-exposed patients is probably less than in infliximab-naive patients. Re-induction with certolizumab in patients who have flared on maintenance therapy can rescue a significant proportion of patients. There is no significant association between the efficacy of certolizumab and the baseline C-reactive protein level. In comparison with placebo, certolizumab does not increase the risk of serious adverse events. Conclusions, Certolizumab is effective and safe in treating Crohn's disease. Further studies are still required to assess its full safety profile. [source]

    Review article: prebiotics in the gastrointestinal tract

    Summary Background Prebiotics are short-chain carbohydrates that alter the composition, or metabolism, of the gut microbiota in a beneficial manner. It is therefore expected that prebiotics will improve health in a way similar to probiotics, whilst at the same time being cheaper, and carrying less risk and being easier to incorporate into the diet than probiotics. Aim To review published evidence for prebiotic effects on gut function and human health. Methods We searched the Science Citation Index with the terms prebiotic, microbiota, gut bacteria, large intestine, mucosa, bowel habit, constipation, diarrhoea, inflammatory bowel disease, Crohn's disease, ulcerative colitis, pouchitis, calcium and cancer, focussing principally on studies in humans and reports in the English language. Search of the Cochrane Library did not identify any clinical study or meta-analysis on this topic. Results Three prebiotics, oligofructose, galacto-oligosaccharides and lactulose, clearly alter the balance of the large bowel microbiota by increasing bifidobacteria and Lactobacillus numbers. These carbohydrates are fermented and give rise to short-chain fatty acid and intestinal gas; however, effects on bowel habit are relatively small. Randomized-controlled trials of their effect in a clinical context are few, although animal studies show anti-inflammatory effects in inflammatory bowel disease, while calcium absorption is increased. Conclusions It is still early days for prebiotics, but they offer the potential to modify the gut microbial balance in such a way as to bring direct health benefits cheaply and safely. [source]

    Principles for modeling propensity scores in medical research: a systematic literature review,

    Sherry Weitzen PhD
    Abstract Purpose To document which established criteria for logistic regression modeling researchers consider when using propensity scores in observational studies. Methods We performed a systematic review searching Medline and Science Citation to identify observational studies published in 2001 that addressed clinical questions using propensity score methods to adjust for treatment assignment. We abstracted aspects of propensity score model development (e.g. variable selection criteria, continuous variables included in correct functional form, interaction inclusion criteria), model discrimination and goodness of fit for 47 studies meeting inclusion criteria. Results We found few studies reporting on the propensity score model development or evaluation of model fit. Conclusions Reporting of aspects related to propensity score model development is limited and raises questions about the value of these principles in developing propensity scores from which unbiased treatment effects are estimated. Copyright 2004 John Wiley & Sons, Ltd. [source]

    Impact of the internet and scholar age distribution on academic citation age

    George A. Barnett
    This article examines the impact of the Internet and the age distribution of research scholars on academic citation age with a mathematical model proposed by Barnett, Fink, and Debus (1989) and a revised model that incorporates information about the online environment and scholar age distribution. The modified model fits the data well, accounting for 99.6% of the variance for science citations and 99.8% for social science citations. The Internet's impact on the aging process of academic citations has been very small, accounting for only 0.1% for the social sciences and 0.8% for the sciences. Rather than resulting in the use of more recent citations, the Internet appears to have lengthened the average life of academic citations by 6 to 8 months. The aging of scholars seems to have a greater impact, accounting for 2.8% of the variance for the sciences and 0.9% for the social sciences. However, because the diffusion of the Internet and the aging of the professoriate are correlated over this time period, differentiating their effects is somewhat problematic. [source]