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1.
P Tugwell L Hart G Kraag A Park C Dok F Bianchi C Goldsmith W W Buchanan 《The Journal of rheumatology》1984,11(4):457-461
A crossover double-blind controlled trial was performed on 36 patients with rheumatoid arthritis to assess the necessity for serum salicylate monitoring in determining optimal dosage. There was no clinically or statistically significant increase in the clinical improvement of patients associated with serum monitoring but potentially toxic serum levels occurred without tinnitus when serum monitoring was not used. 相似文献
2.
Klussmann JP Weissenborn SJ Wieland U Dries V Eckel HE Pfister HJ Fuchs PG 《Medical microbiology and immunology》2003,192(3):129-132
Human papillomavirus (HPV) infections are thought to be one of the causal factors in the development of head and neck squamous cell carcinomas (HNSCC), particularly in tumors arising from the Waldeyer's tonsillar ring. We screened 98 carefully stratified HNSCC and different control tissues for the presence of HPV DNA by nested polymerase chain reaction (PCR) specific for genital- and Epidermodysplasia verruciformis (EV)-associated HPVs and by HPV16-specific single step PCR. Typing was performed by direct sequencing and/or sequencing of cloned amplimers. On average HNSCC showed rather low HPV DNA prevalences; 18% of the oral cavity cancers, 8% of nasopharyngeal cancers, 25% of hypopharyngeal cancers and 7% of laryngeal cancers were HPV DNA positive. In contrast, HPV sequences could be detected in 45% of the oropharyngeal cancers, particularly tonsillar carcinomas (58%). Tonsillar carcinomas were significantly more likely to be HPV positive than tumors from any other site ( P<0.001). All tonsillar cancers contained oncogenic HPV types, predominantly HPV16 (13 of 14; 93%). Unaffected tonsils were available from two of these patients, but both tested negative for HPV DNA. Furthermore, no HPV DNA could be found in tonsillar biopsy specimens from control groups. Localization and load of HPV DNA was determined in HPV16-positive tonsillar carcinomas, their metastases and in unaffected mucosa using laser-assisted microdissection and subsequent real time fluorescence PCR. We demonstrated that the HPV genome is located in the cancer cells, whereas the infection of normal mucosa is a rare event. Quantification of HPV16 DNA in samples of seven patients yielded viral loads from 6 to 153 HPV DNA copies per beta-globin gene copy and the load values in both locations were roughly comparable. These loads are comparable with data shown for other HPV-associated lesions. Statistical evaluation of data related to clinicopathological parameters showed a significant correlation of the HPV positivity of tonsillar carcinomas with tumor grading ( P=0.008) and alcohol consumption ( P=0.029). Taken together our findings show a preferential association of HPV DNA with tonsillar carcinomas. Furthermore our results argue for HPV-positive tonsillar carcinomas representing a separate tumor entity, which is less dependent on conventional HNSCC risk factors. 相似文献
3.
The medicinal leech is one of the few parasitic invertebrates widely used in medicine and as a scientific model object. Because of a dramatic decline in its natural populations, it is subject to considerable conservation effort. Despite all attention, there is confusion regarding the taxonomic status of different morphological forms. The prevailing view is that all varieties of medicinal leech in Europe represent the same species, Hirudo medicinalis. However, the present study based on RAPD molecular markers demonstrates that a second European taxon, H. verbana, forms a distinct species. Phenetic clustering and principal coordinate analysis of eight populations revealed the same basic structure, reflecting taxonomic rather than geographic subdivision. Variation between species explained 60% of the total molecular variance (CT=0.60, P<0.001). Both taxa displayed a significant number of specific RAPD markers. Conversely, no specific fragment supporting the geographic association of both taxa was found. Since the stronghold of commercially exploited medicinal leech populations in southeastern Europe and Turkey belongs to H. verbana, most medicinal and scientific applications probably use this species, not H. medicinalis. Appropriate taxonomic correction of international conservation conventions and legislation is essential. 相似文献
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6.
Torrance GW Blaker D Detsky A Kennedy W Schubert F Menon D Tugwell P Konchak R Hubbard E Firestone T 《PharmacoEconomics》1996,9(6):535-559
In 1994, Canada became the second country to release national guidelines for the economic evaluation of pharmaceuticals. The guidelines were developed over a period of 18 months through an elaborate process of broad consultation with a wide variety of relevant stakeholders. The intent of the guidelines is to provide guidance to doers and users of studies, by laying out the general 'state of the art' regarding methods, and by providing specific methodological advice on many matters. The aim is to improve the scientific quality and integrity of studies, and to enhance consistency and comparability across studies. This article presents the Canadian guidelines, both in summary and in detail. Because the techniques of economic evaluation are widely applicable beyond pharmaceuticals, the guidelines will be of interest to researchers and decision makers in all fields of healthcare. Because the methods are not country specific, the guidelines will be of interest to those in other countries as well as in Canada. 相似文献
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Simcha M. Russak Joseph D. Croft Daniell E. Furst Andriana Hohlbauch Matthew H. Liang Larry Moreland Joshua J. Ofman Harold Paulus Lee S. Simon Michael Weisman Peter Tugwell 《Arthritis care & research》2003,49(4):574-584
Objective
The utilization of health‐related quality of life (HRQOL) patient questionnaires by clinical rheumatologists is limited. Yet, considerable literature exists defining the value of such data. In an effort to understand this apparent paradox, we performed a literature review and conducted a survey to describe what has been learned over the past 2 decades concerning the use of these measures in clinical care and explore the reasons for their underutilization.Methods
A panel of rheumatologists with extensive clinical experience was convened to review the relevant literature pertaining to the use of HRQOL patient instruments in clinical practice. Additionally, a survey of all American College of Rheumatology practicing clinicians was conducted to assess the use of and beliefs about these measures.Results
The literature provided evidence to support the use of HRQOL patient measures in clinical practice. Forty‐seven percent of the responding rheumatologists stated that none of their patients complete HRQOL patient questionnaires. The majority of respondents (63%) reported that such information is “somewhat valuable.” The most frequently reported reason for the underutilization was that such instruments “require too much staff time.”Conclusions
The literature supports the potential value of HRQOL patient questionnaires in clinical practice. Few rheumatologists routinely gather such information as part of patient care. Reasons for this discrepancy between utility and use are given along with recommendations intended to help increase their utilization in clinical care.9.
The prevention of chronic NSAID induced upper gastrointestinal toxicity: a Cochrane collaboration metaanalysis of randomized controlled trials 总被引:5,自引:0,他引:5
Rostom A Wells G Tugwell P Welch V Dubé C McGowan J 《The Journal of rheumatology》2000,27(9):2203-2214
OBJECTIVE: To review the effectiveness of common interventions for the prevention of nonsteroidal antiinflammatory drug (NSAID) induced upper gastrointestinal (GI) toxicity. METHODS: Randomized controlled clinical trials (RCT) of prostaglandin analogs, H2-receptor antagonists (H2RA), or proton pump inhibitors (PPI) for the prevention of chronic NSAID induced upper GI toxicity were identified through electronic databases, the Cochrane control trials register, conference proceedings, and by contacting content experts and companies. Outcome measures investigated were endoscopic ulcers, ulcer complications, symptoms, overall dropouts, dropouts due to symptoms, and study quality. RESULTS: Thirty-four RCT met the inclusion criteria. All doses of misoprostol significantly reduced the risk of endoscopic ulcers. Misoprostol 800 microg/day was superior to 400 microg/day for the prevention of endoscopic gastric ulcers (RR 0.18, RR 0.38, respectively; p = 0.0055). A dose-response relationship was not seen with duodenal ulcers. Misoprostol caused diarrhea at all doses, although significantly more at 800 than 400 microg/day (p = 0.0012). Misoprostol was the only prophylactic agent documented to reduce ulcer complications. Standard doses of H2RA were effective at reducing the risk of endoscopic duodenal (RR 0.24, 95% CI 0.10-0.57) but not gastric ulcers (RR 0.73, 95% CI 0.50-1.09). Both double dose H2RA and PPI were effective at reducing the risk of endoscopic duodenal and gastric ulcers (RR 0.44, 95% CI 0.26-0.74 and RR 0.37, 95% CI 0.27-0.51, respectively, for gastric ulcer) and were better tolerated than misoprostol. CONCLUSION: Misoprostol, PPI, and double dose H2RA are effective in preventing chronic NSAID related endoscopic gastric and duodenal ulcers. Lower doses of misoprostol are less effective and are still associated with diarrhea. Only misoprostol 800 microg/day has been directly shown to reduce the risk of ulcer complications. 相似文献
10.