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101.
Background Allergic rhinitis (AR) and asthma often coexist and may represent two manifestations of the same disease recently named combined AR and asthma syndrome (CARAS). Aim To review the common pathophysiology of combined AR and asthma and to investigate the efficacy of intranasal corticosteroids (INCS). Methods Medline was used to identify articles relevant to mechanisms. A Cochrane systematic review was performed to assess the efficacy of INCS in CARAS. Results There is cross‐talk, evidence of a common inflammatory response in both sites, linked by a systemic component. The efficacy of anti‐inflammatory INCS on asthma outcomes was assessed in a systematic review of 12 randomized controlled trials involving 425 subjects. After INCS there were non‐significant trends for improvement in asthma symptom score (standardized mean difference (SMD) of 0.61; P=0.07), forced expiratory volume in 1 s (SMD of 0.31; P=0.08), and morning peak expiratory flow (weighted mean difference of 36.51; P=0.06). There was no impact on methacholine airways responsiveness (SMD of ?0.20; P=0.4). The review identified two promising new treatment options in united airway disease such as INCS as monotherapy in rhinitis and mild asthma, and a combined intranasal and intrabronchial corticosteroid (IBCS) deposition technique. Conclusion Common mucosal inflammatory responses occur in CARAS. This systematic review shows trends for a benefit of INCS in CARAS, but recognizes that more research is needed. At this stage, the current best practice is to treat asthma conventionally with IBCS with or without β2‐agonist and to add INCS to improve specific rhinitis symptoms.  相似文献   
102.
S D Walter 《Annals of oncology》2003,14(8):1190-1192
BACKGROUND: The case-control design can be used to evaluate the benefit of cancer screening programmes. MATERIALS AND METHODS: This paper outlines the main methodological features of the case-control design in this context, and indicates some potential biases. It also reviews the existing case-control literature on mammographic screening. RESULTS: Case-control studies consistently indicate a reduction of approximately 50% in breast cancer mortality associated with mammography. This result indicates greater benefit than shown in randomised trials; however, one should recognise that trials indicate effectiveness whereas case-control studies indicate efficacy. The two types of evidence are broadly compatible when one allows for screening non-compliance and contamination in the randomised trials. CONCLUSIONS: The case-control evidence supports and is consistent with the findings of randomised trials of mammography. Effectiveness estimates from trials indicate the benefit of screening to the population as a whole, and are pertinent to the public policy debate as to the value of offering screening. In contrast, case-control studies indicate benefit to actual screening participants. As such, case-control estimates of efficacy are appropriate for individual decision-making by women about their use of mammography when it is potentially available to them.  相似文献   
103.
Bayesian decision theoretic approaches (BDTAs) have been widely studied in the literature as tools for designing and conducting phase II clinical trials. However, full Bayesian approaches that consider multiple endpoints are lacking. Since the monitoring of toxicity is a major goal of phase II trials, we propose an adaptive group sequential design using a BDTA, which characterizes efficacy and toxicity as correlated bivariate binary endpoints. We allow trade‐off between the two endpoints. Interim evaluations are conducted group sequentially, but the number of interim looks and the size of each group are chosen adaptively based on current observations. We utilize a loss function consisting of two components: the loss associated with accruing, treating, and monitoring patients, and the loss associated with making incorrect decisions. The performance of our Bayesian modeling, and the operating characteristics of decision rules under a wide range of loss function parameters are evaluated using seven scenarios in a simulation study. Our method is illustrated in the context of a single‐arm phase II trial of bevacizumab, gemcitabine, and oxaliplatin in patients with metastatic pancreatic adenocarcinoma. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
104.
Introduction There is debate about the type and intensity of early childhood intervention that is most helpful for children with developmental problems. The aim of the study was to determine whether a home‐based programme provided over 12 months resulted in sustained improvement in development and behaviour 12 months after the intervention ceased. The characteristics of the children and families who benefited most from the intervention were also studied. Method Randomized controlled trial. Participants A total of 59 children, aged 3–5 years, attending two early childhood intervention centres in Melbourne, Australia. Intervention Half of the subjects received an additional home‐based programme consisting of 40 weekly visits. Main outcome measures Bayley Scales of Infant Development and Wechsler Preschool and Primary Scale of Intelligence Revised, Preschool Behaviour Checklist, Bayley Behaviour Rating Scale and Behaviour Screening Questionnaire. All tests administered pre‐intervention, following the intervention and 12 months later. Secondary outcome measures Family stress, support and empowerment. Results Fifty‐four children completed the assessments 12 months after conclusion of the intervention. Compared with the control group, improvement in aspects of cognitive development in the children who received the extra intervention was sustained 1 year later (P= 0.007) while significant behavioural differences post intervention were not. Analyses of the data by the Reliable Change Index indicated improvement of clinical significance occurred in non‐verbal areas. In contrast to the control group who deteriorated, language skills in the intervention group remained stable. Improvements were significantly associated with higher stress in the families. Conclusion Improvements following the provision of a home‐based programme to preschool children with developmental disabilities were sustained 1 year later. Children from highly stressed families appeared to benefit most, reinforcing the importance of involving families in early childhood intervention programmes.  相似文献   
105.
106.
Objectives:To assess the clinical outcomes of frozen-thawed blastocysts transfer in natural and hormonally controlled cycles.Methods:A retrospective analysis of natural and hormonally controlled cycle for 246 frozen-thawed blastocyst transfer cycles,the clinical pregnancy rate,implantation rate,early abortion rate were compared.Results:Of the 192 hormonally controlled cycles,the cancel rate,clinical pregnancy rate per ET,implantation rate and abortion rate were 7.3%(14/192),53.9%(96/178),38.8%(131/338)and 11.5%(11/96)respectively,whereas in 54 natural cycles,these rates were 16.7%(9/54),68.9%(31/45),52.9%(45/85)and 16.1%(5/31)respectively.There was no significant difference between the two groups with regard to the clinical pregnancy and abortion rate per ET,but the cancel rate and implantation rate were higher in natural cycles.However,the pregnancy and implantation rates of patients without PCOS in hormonal control cycles(57.2%,40.9%)were similar with those in natural cycles(P>0.05).Conclusion:These findings suggested that both hormonally controlled and natural cycles had similar pregnancy outcomes in frozen-thawed blastocysts transfer.  相似文献   
107.
108.
ABSTRACT: Background: The addition of supplementary prenatal support may improve the health and well‐being of high‐risk women and families. The objective of this randomized controlled trial was to examine the impact of supplementary prenatal care on resource use among a community‐based population of pregnant women. Methods: Pregnant women from three urban maternity clinics were randomized (a) to current standard of physician care, (b) to current standard of care plus consultation with a nurse, or (c) to (b) plus consultation with a home visitor. Participants were 1,352 women who received 3 telephone interviews. The primary outcome was resource use (e.g., attended prenatal classes, used nutritional counseling). Results: Overall, those in the nurse intervention group were more likely to attend an “Early Bird” prenatal class and parenting classes, and to use nutrition counseling and agencies that assist with child care. Women provided with extra nursing and home visitation supports were more likely to use a written resource guide, nutrition counseling, and agencies that assist with child care. Among women at higher risk (e.g., language barriers, young maternal age, low income), the nurse intervention significantly increased use of early prenatal classes, whereas the nurse and home visitor intervention significantly increased use of the written resource guide and nutrition counseling. The intervention substantially increased the amount of information received on numerous pregnancy‐related topics but had little impact on resource use for mental health and poverty‐related needs. Among those with added support, resource use among low‐risk women was generally greater than among high‐risk women. Conclusions: Additional support provided by nurses, or nurses and home visitors, can successfully address informational needs and increase the likelihood that women will use existing community‐based resources. This finding was true even for high‐risk women, although this intervention did not reduce the difference in resource use between high‐ and low‐risk women. (BIRTH 33:3 September 2006)  相似文献   
109.
AIMS: To develop and test the sensitivity and precision of a rapid and simple search filter (RSSF), suitable for busy clinicians wanting to find randomised controlled trials (RCTs) in PubMed. Ideally it should retrieve all the RCTs, but as few irrelevant studies as possible, and be easy to use. METHODS: The RSSF consisted of the search term 'Randomized Controlled Trial' limited to the Publication Type field. Journals that published the highest numbers of diabetes RCTs between 2000 and 2005 were identified, and then handsearched in order define a set of known RCTs. The sensitivity of the RSSF was tested by measuring the proportion of the known RCTs retrieved, and the precision by checking the proportion of the retrieved studies which were RCTs. The RSSF was compared to a highly sensitive search strategy (HSSS) developed for PubMed. Embase was checked for trials not in PubMed. RESULTS: Sixteen journals were found to contain half of all published RCTs in diabetes. 820 diabetes RCTs were identified by handsearching. Measured against these, the RSSF gave a sensitivity of 96.0% (95% CI, 94.8% to 97.1%), and a precision of 93.6% (95% CI 91.7% to 95.0%). Compared to the HSSS, the RSSF reduced the filtering required by 87%. An Embase search for diabetes RCTs found 36 (2.1%) not in PubMed. CONCLUSIONS: A rapid simple search filter for PubMed can find almost all diabetes RCTs, while excluding most studies not required, thereby greatly reducing the time cost of searching and filtering results, and of searching other databases.  相似文献   
110.
There is accumulating evidence, reviewed by Caudiano (this issue), that cognitive behavior therapy (CBT) is an effective adjunct treatment for schizophrenia. Schizophrenia treatment and research provides a range of challenges that are probably not present in other mental health problems. These include contextual issues, clinical issues, scientific and methodological issues, practical and pragmatic issues, public concern, and human rights issues. This paper discusses these issues with emphasis on the clinical and research challenges for the future.  相似文献   
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