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排序方式: 共有10000条查询结果,搜索用时 46 毫秒
51.
《International Business Review》2021,30(5):101813
This paper develops a systematic literature review about up- and down- alliances: vertical alliances (VAs) characterized by long term continuity between firms operating in adjacent stages of a value chain. Vertical alliances are a must for firms operating in a complex and unstable world, because they guarantee the advantages deriving from the vertical coordination of the value chain as well as the flexibility of cooperation.In spite of the copious literature on alliances, few contributions focus specifically on VAs, so a clear overview of the phenomenon is missing. Furthermore, the different terminology and definitions found in the literature are confusing. Our systematic literature review identifies the theoretical approaches which are most used to study the development, potential and dynamics of VAs. The review highlights the main theories and the most explored topics, and identifies the gaps still existing in the literature. From the review, we developed a taxonomy to determine which research stream would be most congruent to a specific research topic. 相似文献
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Using Vendor Managed Inventory (VMI), the vendor determines the replenishment decisions at the location of buyers (retailers). This strategy is used primarily for handling demand fluctuations stemming from the Bullwhip effect, leading the system to prevent from holding excessive inventory that result in a reduction in the overall cost of the supply chain. The main advantages of VMI for vendors are higher levels of accessibility to inventory information and more direct contact with the customers. Similarly, VMI has some pros for the buyers, such as shared risk with upper levels of supply chain and reduction in their holding costs of inventory. In this paper, a vendor-managed inventory system is developed containing one vendor and two buyers in which the main assumption is that back-ordering and lost sales are permitted. In this system, (r, Q) and (R, T) replenishment policies are compared according to their performances to see which one performs more cost-efficiently when partial back-ordering is allowed. In accordance, mathematical models utilizing (r, Q) and (R, T) replenishment policies are developed, and algorithms for deriving the optimal replenishment decision variables are proposed. Moreover, significant differences between the two replenishment policies are discussed. The main finding obtained by this research is that when shortage is permitted, both (r, Q) and (R, T) replenishment policies under VMI have pros and cons in different contexts. 相似文献
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Background:The progress of modern society and changes in lifestyle have not only increased the proportion of sub-healthy people, but also caused many people to suffer from sleep disorders and mental anxiety. Long-term lack of high-quality sleep will not only cause psychological problems such as anxiety and fatigue, but also cause physical abnormalities, such as abnormal hormone secretion, weakened immunity, neuroendocrine disorders, and high blood pressure. Therefore, the purpose of this study is to systematically evaluate the effectiveness of aromatherapy in improving sleep quality in people with sleep disorders.Methods:Computer search CNKI, SinoMed, Wanfang, PubMed, Web of science, and EMbase collect randomized controlled trials on aromatherapy to improve sleep quality of people with sleep disorders. The search time limit is to build the database until April 5, 2021. RevMan5.3 software is used for meta-analysis.Results:This systematic review will provide an assessment of the current state of sleep disorders, aiming to assess the efficacy of aromatherapy for patients with sleep disorders.Conclusion:This systematic review will provide a credible evidence-based for the clinical treatment of sleep disorders with aromatherapy. 相似文献
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Katie Mycock Lin Zhan Gavin Taylor-Stokes Gary Milligan Debanjali Mitra 《Current oncology (Toronto, Ont.)》2021,28(1):678
Background: Palbociclib is a selective cyclin-dependent kinase (CDK) 4/6 inhibitor used in combination with aromatase inhibitors or fulvestrant for patients with hormone receptor-positive (HR+) human epidermal growth factor receptor 2 (HER2)-negative advanced/metastatic breast cancer (ABC/MBC). Palbociclib was the first CDK 4/6 inhibitor approved for HR+/HER2− ABC/MBC treatment in Canada in combination with letrozole (P+L) as an initial endocrine-based therapy (approved March 2016), or with fulvestrant (P+F) following disease progression after prior endocrine therapy (approved May 2017). The Ibrance Real World Insights (IRIS) study () collected real-world outcomes data for palbociclib-treated patients in several countries, including Canada. Methods: This retrospective chart review included women with HR+/HER2− ABC/MBC receiving P+L or P+F in Canada. Physicians reviewed medical records for up to 14 patients, abstracting demographic and clinical characteristics, treatment patterns, and clinical outcomes. Progression-free rates (PFRs) and survival rates (SRs) at 6, 12, 18, and 24 months were estimated via Kaplan–Meier analysis. Results: Thirty-three physicians examined medical records for 247 patients (P+L, n = 214; P+F, n = 33). Median follow-up was 8.8 months for P+L and 7.0 months for P+F. Most patients were initiated on palbociclib 125 mg/d (P+L, 90.2%; P+F, 84.8%). Doses were reduced in 16.6% of P+L and 14.3% of P+F patients initiating palbociclib at 125 mg/d. The PFR for P+L was 90.3% at 12 months and 78.2% at 18 months; corresponding SRs were 95.6% and 93.0%. For P+F, 6-month PFR was 91.0%; 12-month SR was 100.0%. Conclusions: Dose reduction rates were low and PFR and SR were high in this Canadian real-world assessment of P+L and P+F treatments, suggesting that palbociclib combinations are well tolerated and effective. NCT03159195相似文献
56.
BackgroundGluten- and lactose-free products are registering a sudden rise in the market, particularly among tolerant people, and this leads to consumer confusion and nutritional inadequacies. The number of studies around this trend has steadily increased in the last 10 years, as scholars from different disciplines have tried to rationalize consumers’ behaviours in these foods’ choice. However, the scientific debate appears fragmented and lacks an integrated view.ObjectivesWe conducted a systematic integrative review of consumers’ determinants of gluten-free and lactose-free consumption to frame the state of the art and research gaps.Methods45 English language articles reporting quantitative empirical studies ranging from 1971 and 2019 were analysed. First we categorized the consumption determinants in six factors applying the model proposed by Koster and Mojet, then we proposed a new integrated conceptualization inspired by Bronfenbrenner’s Transtheoretical Model. Moreover, differences and similarities between tolerant and intolerant consumers will be highlighted.ResultsResearch on intolerant consumers focused more on individuals’ determinants, in terms of awareness, trust, morality, and capability to read nutritional facts (as purchase facilitators); while studies targeting tolerant consumers focused more on objective product characteristics (with price and availability in supermarkets as barriers for consumption). In this target the subjective perspective has been studied only referring to the risk for developing psychological issues in the restrictive diet.ConclusionAs information is lacking in the scientific debate, we suggest for future research the integration of consumers’ subjective implicit levers to decipher free-from purchase behaviours. 相似文献
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Sarah Hallas Andrea Nelson Susan O'Meara Una Adderley Pauline Meskell Jane Nixon Aonghus O'Loughlin Sebastian Probst Wael Tawfick Thomas Wild Georgina Gethin 《Journal of tissue viability》2021,30(3):317-323
BackgroundA venous leg ulcer is a chronic leg wound caused by poor venous blood circulation in the lower limbs. It is a recurring condition causing pain, malodour, reduced mobility, and depression. Randomised controlled trials evaluating treatments for venous leg ulcers provide important evidence to inform clinical decision-making. However, for findings to be useful, outcomes need to be clinically meaningful, consistently reported across trials, and fully reported. Research has identified the large number of outcomes reported in venous leg ulcer trials, impacting both synthesis of results, and clinical decision-making. To address this, a core outcome set will be developed. A core outcome set is an agreed standardised set of outcomes which should be, as a minimum, measured and reported in all trials which evaluate treatment effectiveness for a given indication. A core outcome set has the potential to reduce research waste, improve the utility of RCTs, reduce reporting bias, facilitate treatment comparisons across different sources of evidence and expedite the production of systematic reviews, meta-analyses and evidence-based clinical guidelines.AimThe aim of this project is to develop a core outcome set for research evaluating the effectiveness of interventions for treating venous leg ulceration.MethodsThrough a scoping review of the literature on venous leg ulceration, we will firstly identify a list of candidate outcome domains (broad categories in relation to what is being measured) from randomised controlled trials and qualitative research, and outcomes (specific methods in relation to what is being measured). In two further stages, we will use the resulting lists of outcome domains and outcomes to design two online surveys. A range of stakeholders will be invited to participate in the surveys and they will be asked to indicate which outcome domains and outcomes are most important and should be considered as core in future research reports. 相似文献
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预制拼装桥墩体系(Pre-fabricated Concrete PierSystem, PCP)抗震性能是影响其推广、应用的关键。为加快PCP在中、高烈度等复杂恶劣工程环境中的设计、施工与建造,首先综述了PCP节点连接的接缝形式、连接构造类型及典型工程示例,指出了PCP常用3种接缝形式和6种连接构造力学性能的研究现状及其优缺点;其次,系统地梳理了PCP抗震性能的研究进展,分析了不同连接条件下PCP的抗震性能,明晰了现有PCP抗震性能研究的不足及未来研究方向;最后,详细地论述了PCP抗震性能提升方法的研究前沿,探究了耗能延性构造的设置、高性能材料的应用、新型装配式节点构造设计以及新型混合预制桥墩体系的提出等PCP抗震性能提升方法的优缺点和发展方向。结果表明:通过对装配式节点的合理设计以及薄弱区域的预处理,预制拼装桥墩体系的抗震性能能够达到“等同现浇”的设计原则。然而PCP在复杂恶劣工程环境中的推广应用仍面临以下关键问题:PCP既有节点连接方式、体系和改进措施的抗震性能研究成果亟需归纳;新型节点连接方式、新体系和新型改进措施亟待提出,相关抗震性能有待验证;既有和新型PCP抗震性能的理论分析及抗震设计方法尚需完善;适用于复杂恶劣环境的预制拼装桥墩设计、施工标准亟需制定。 相似文献
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