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《Molecular therapy》2022,30(6):2186-2198
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Safety standards for clinical diagnostic ultrasonic devices were developed for use in relatively low-frequency systems (1–10 MHz), under the assumption that non-linear effects would be negligible. This article reviews ways in which neglecting non-linear wave propagation affects the measurements and calculations required to comply with safety standards and U.S. Food and Drug Administration guidance that recognizes these standards. An attempt is made to evaluate whether ignoring non-linear effects could result in significant error in the exposure quantities defined in these standards at either low or high frequencies, based on published literature. This article maintains that although non-linear effects have been considered in some parts of safety standards related to hydrophone requirements, the coverage is inadequate, especially for modern equipment with high working frequencies. A new approach is required to assess the magnitude of thermal heating for recently developed high-frequency systems to incorporate non-linear effects. In contrast, the current approach for evaluating the risk of cavitation can be used after appropriate modifications.  相似文献   
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薄层色谱鉴别在历版《中国药典》中的应用经历了从无到有、从少到多的过程;而薄层扫描含量测定在最近几版《中国药典》中的应用比例逐渐降低。随着对中药质量标准体系要求的进一步提高,薄层色谱法的不足之处陆续显现,如仪器普及率低、设备并不简单、结果重复性和稳定性较差、鉴别速度及准确性不及高效液相色谱法、展开剂毒性大等,逐渐不合时宜。在制定中药质量标准时,研究者不应该墨守成规,薄层色谱鉴别也不应该是雷打不动的定性鉴别必备选项。高效液相色谱法具备完全取代薄层色谱法的可行性,薄层色谱法可作为高效液相色谱法的补充。为充分降低检测成本、缩短检测周期、提高鉴别效率,笔者建议中药质量标准体系应该大幅减少薄层色谱鉴别方法的应用,增加高效液相特征图谱鉴定,尽量做到“一个条件,一张图谱”;除非确有必要,《中国药典》等国家质量标准体系应将薄层色谱鉴别作为推荐方法,而非强制标准。  相似文献   
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The Royal Australian and New Zealand College of Radiologists (RANZCR) Radiology Written Report Guideline was first issued in 2011. A survey‐based consultation of clinical radiology members of the college in 2015 found that the vast majority of 235 respondents supported all components of the guideline. Since the original guideline was developed, considerable new research has been published about radiology reporting, particularly regarding structured/template reports. In 2016/17 a RANZCR working group used the consultation results, stakeholder feedback and recent research to develop revised guidelines. This article outlines the consultation survey results and guideline revision process as well as some of the supporting evidence from the literature.  相似文献   
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Colorectal cancer (CRC) is the third most common cancer worldwide after lung and breast cancers, and ranks second in terms of cancer mortality globally. Brunei Darussalam reports high incidence of CRC in the Southeast Asian region and has no formal national screening programme for CRC. Screening for CRC in Brunei Darussalam is offered in an opportunistic fashion for individuals with average or above average risks for CRC, that is, the individual has a positive family history of CRC or neoplasms and is more than 50 years old. Opportunistic screening is widely practiced but this is not standardised. The Ministry of Health in Brunei Darussalam is currently in the process of implementing a CRC screening programme as part of a larger national health screening based on the increasing incidence of non-communicable diseases (NCDs). This review article assesses the situation of CRC in Brunei Darussalam from the 1980s to present day, including incidence of CRC in different age groups, ethnicities and genders; relevant non-modifiable and modifiable risk factors of CRC in Brunei Darussalam setting; and common CRC screening techniques used in Brunei Darussalam as well as other Asia-Pacific countries. The review also discusses the merits of a national CRC screening programme. With the increasing incidence of CRC worldwide and in Brunei Darussalam, national screening for CRC in Brunei Darussalam is an important strategy to lower morbidity and mortality rates. A review of the progress and outcome of the national screening programme will be available a few years after rollout.  相似文献   
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马迪  郝妍妍  陈旭阳  李建银  张军民 《中草药》2020,51(9):2557-2572
香药是古代"丝绸之路"交流发展逐渐传入中国的传统药物,补充并丰富了我国药用资源。为积极倡导国家"一带一路"建设,推进我国外来香药资源的进一步开发和利用,服务"一带一路"沿线国家广大人民尤其是少数民族人群健康用药,通过查阅大量文献,梳理了香药的"一带一路"溯源及目前研究现状;在此基础上,从中医功效角度对其进行分类,并总结常用代表性香药的香味物质基础、功效及临床用途;并提出香药的进一步开发和利用策略,以促进其在新时代"一带一路"倡议中的快速发展,进一步增强民族医药文化自信。  相似文献   
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Many trainees think about research towards the end of clinical training, but at that stage, it may be too late to get the most from the limited opportunities that remain. Ideally, trainees should consider research early in their career. For some, a career in academic paediatrics may be attractive, in which case following the clinical academic pathway as outlined by the National Institutes of Health Research may be appropriate. For others, research may be part of a wider clinical training. This article discusses a variety of research opportunities available to trainees, and offers advice on a career in academic paediatrics.  相似文献   
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