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Gerald Gartlehner Suzanne L West Kathleen N Lohr Leila Kahwati Jana G Johnson Russell P Harris Lynn Whitener Christiane E Voisin Sonya Sutton 《International journal for quality in health care》2004,16(5):399-406
BACKGROUND: An important concern for developers of clinical practice guidelines is how best to determine when guidelines require updating to ensure they remain current and evidence based. Because of the high costs associated with updating guidelines, recent attention has focused on approaches that can reliably assess the extent of updating required. Recently, Shekelle and colleagues proposed a model of limited literature searches with modest expert involvement as a way to reduce the cost and time requirements for assessing whether a guideline needs updating. METHODS: The main objective of this study was to compare the Shekelle et al. assessment model (review approach) and a conventional process using typical systematic review methods (traditional approach) in terms of comprehensiveness and effort. We modeled the review approach on that by Shekelle and colleagues but refined it iteratively over three phases to achieve greater efficiency. Using both methods independently, we assessed the need to update six topics from the 1996 Guide to Clinical Preventive Services from the US Preventive Services Task Force. Main outcomes included completeness of study identification, importance of missed studies and the effort involved. RESULTS: Although the review approach identified fewer eligible studies than the traditional approach, none of the studies missed was rated as important by task force members acting as liaisons to the project with respect to whether the topic required an update. On average, the review approach produced substantially fewer citations to review than the traditional approach. The effort involved and potential time saving depended largely on the scope of the topic. CONCLUSIONS: The revised review approach provides an efficient and acceptable method for judging whether a guideline requires updating. 相似文献
83.
Kathrin Mühlemann Christine Franzini Christoph Aebi Christoph Berger David Nadal Jody St?helin Hanspeter Gnehm Klara Posfay-Barbe Alain Gervaix Hugo Sax Ulrich Heininger Jan Bonhoeffer Gerhard Eich Christian Kind Christiane Petignat Pietro Scalfaro 《Infection control and hospital epidemiology》2004,25(9):765-771
OBJECTIVE: To acquire data on pediatric nosocomial infections (NIs), which are associated with substantial morbidity and mortality and for which data are scarce. DESIGN: Prevalence survey and evaluation of a new comorbidity index. SETTING: Seven Swiss pediatric hospitals. PATIENTS: Those hospitalized for at least 24 hours in a medical, surgical, intensive care, or intermediate care ward. RESULTS: Thirty-five NIs were observed among 520 patients (6.7%; range per hospital, 1.4% to 11.8%). Bacteremia was most frequent (2.5 per 100 patients), followed by urinary tract infection (1.3 per 100 patients) and surgical-site infection (1.1 per 100 patients; 3.2 per 100 patients undergoing surgery). The median duration until the onset of infection was 19 days. Independent risk factors for NI were age between 1 and 12 months, a comorbidity score of 2 or greater, and a urinary catheter. Among surgical patients, an American Society of Anesthesiologists (ASA) score of 2 or greater was associated with any type of NI (P = .03). Enterobacteriaceae were the most frequent cause of NI, followed by coagulase-negative staphylococci; viruses were rarely the cause. CONCLUSIONS: This national prevalence survey yielded valuable information about the rate and risk factors of pediatric NI. A new comorbidity score showed promising performance. ASA score may be a predictor of NI. The season in which a prevalence survey is conducted must be considered, as this determines whether seasonal viral infections are observed. Periodic prevalence surveys are a simple and cost-effective method for assessing NI and comparing rates among pediatric hospitals. 相似文献
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Feasibility study for the rapid determination of the amylose content in starch by near-infrared spectroscopy. 总被引:3,自引:0,他引:3
Christiane C Fertig Fridrun Podczeck Roger D Jee Mark R Smith 《European journal of pharmaceutical sciences》2004,21(2-3):155-159
Near-infrared (NIR) spectroscopy was used to determine the amylose content in six different starches, whose declared amylose contents ranged from 2 to 95% m/m. The amylose content of starches can vary considerably between batches depending on growth conditions and time of harvesting. An NIR calibration model was developed for amylose using simple laboratory produced mixtures of amylose and amylopectin in different ratios. The spectral region at 1700-1800nm showed a good correlation to the amylose content of these mixtures. A simple absorbance ratio calibration model using standard normal variate and first derivative pre-treated spectra gave a root mean standard error of prediction of 1.2% m/m. Application to real samples gave amylose contents in reasonable agreement with the average values stated by the supplier. NIR spectroscopy provides a rapid and non-destructive method for the quantitative determination and standardisation of amylose in starch and could make a suitable alternative to traditional techniques, such as complex formation of starch with iodine or n-butanol. 相似文献
88.
Christiane Devaux Besma Jouirou Mohamed Naceur Krifi Olivier Clot-Faybesse Mohamed El Ayeb Hervé Rochat 《Toxicon》2004,43(6):661-669
Scorpion stings represent a medical problem in numerous countries. The scorpion Androctonus australis hector produces three alpha toxins (Aah I to III), which are responsible for most of the lethality in mammals. These toxins act on sodium channel and do not cross-react immunologically. We used RIA and ELISA to measure the concentrations of these three toxins in plasma, urine and different organs after i.v. and s.c. injections of water extracts of venoms in rabbits or mice. In both animals, the toxins rapidly appeared in plasma after s.c. injection as it was previously described for the whole venom. However, the toxins disappeared from the blood more quickly than did other main components of the venom. Thus, serotherapy must be initiated immediately to prevent the toxin from reaching its target. We also detected the toxins in urine, kidneys, heart and lungs, but not in the brain. However, the concentration of Aah II was always lower than that of Aah I. Analysis of five samples of venom collected in different areas of southern Tunisia showed that a large polymorphism exists for the three toxins. This is yet another difficulty for serotherapy as there is no cross-antigenicity between them. 相似文献
89.
Christiane Al‐Haddad Ziad Bashour Lina Farah Layal Bayram Zeina Merabe Riad Ma'luf Ramzi Alameddine Toufic Eid Fadi Geara Matthew Wilson Rachel Brennan Sima Jeha Khaled Ghanem Rasha Al Yousef Roula Farah Peter Noun Nabil Yassine Adlette Inati Samar Muwakkit Miguel Abboud Nidale Tarek Dima Hamideh Raya Saab 《Pediatric blood & cancer》2019,66(11)
Retinoblastoma is an ocular tumor that occurs in young children, in either heritable or sporadic manner. The relative rarity of retinoblastoma, and the need for expensive equipment, anesthesia, and pediatric ophthalmologic expertise, are barriers for effective treatment in developing countries. Also, with an average age‐adjusted incidence of two to five cases per million children, patient number limits development of local expertise in countries with small populations. Lebanon is a small country with a population of approximately 4.5 million. In 2012, a comprehensive retinoblastoma program was formalized at the Children's Cancer Institute (CCI) at the American University of Beirut Medical Center, and resources were allocated for efficient interdisciplinary coordination to attract patients from neighboring countries such as Syria and Iraq, where such specialized therapy is also lacking. Through this program, care was coordinated across hospitals and borders such that patients would receive scheduled chemotherapy at their institution, and monthly retinal examinations and focal laser therapy at the CCI in Lebanon. Our results show the feasibility of successful collaboration across borders, with excellent patient and physician adherence to treatment plans. This was accompanied by an increase in patient referrals, which enables continued expertise development. However, the majority of patients presented with advanced intraocular disease, necessitating enucleation in 90% of eyes in unilateral cases, and more than 50% of eyes in bilateral cases. Future efforts need to focus on expanding the program that reaches to additional hospitals in both countries, and promoting early diagnosis, for further improvement of globe salvage rates. 相似文献
90.
Serum microRNA profiles as prognostic/predictive markers in the multimodality therapy of locally advanced adenocarcinomas of the gastroesophageal junction
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Ines Gockel Leila Sisic Jolly Schmitz Nikolas H. Stoecklein Christiane Driemel Birte Möhlendick Thomas Schmidt Wolfram T. Knoefel Hauke Lang Reinhard Büttner Daniel Vallböhmer 《International journal of cancer. Journal international du cancer》2015,137(1):230-237
Neoadjuvant multimodality treatment is frequently applied to improve the poor prognosis of locally advanced adenocarcinomas of the gastroesophageal junction. This study aimed to asses if serum microRNA profiles are useable as response indicators in this therapeutic setting. Fifty patients with locally advanced adenocarcinomas of the gastroesophageal junction were included in the study. All patients received neoadjuvant therapy and subsequently underwent surgical resection. Histomorphologic regression was defined as major histopathological response when resected specimens contained less than 10% vital residual tumor cells. Circulating RNA was isolated from pretherapeutic/post‐neoadjuvant blood serum samples. RNA from nine patients was applied to PCR microarray analyses Based on these findings possible predictive miRNA markers were validated by quantitative RT‐PCR analyses. Depending on the histomorphologic regression, a differential serum microRNA profile was identified by microarray analyses. Based on the divergent miRNA pattern, miR‐21, miR‐192, miR‐222, miR‐302c, miR‐381 and miR‐549 were selected for further validation. During neoadjuvant therapy, there was a significant increase of miR 222 and miR‐549. Although on an expanded patient cohort, the six microRNAs could not be validated as markers for therapy response, there was a significant correlation between a high miR‐192 and miR‐222 expression with a high T‐category as well as miR‐302c and miR‐222 expression significantly correlated with overall survival. Comprehensive miRNA profiling showed a differential microRNA expression pattern depending on the histomorphologic regression in the multimodality therapy of locally advanced adenocarcinomas of the gastroesophageal junction. Moreover, using single RT‐PCR analyses a prognostic impact of miR‐222 and miR‐302c was detected. 相似文献