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41.
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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Background and objectivesRecent research has identified neighborhoods as an important contributor to later-life frailty. However, little is known about how neighborhood resources are associated with frailty trajectories over time, especially in developing countries. This study examines the impact of neighborhood physical and social resources on the trajectories of frailty over time among older people in China.Research design and methodsUsing the four waves of the China Health and Retirement Longitudinal Study (2011–2018), 5673 respondents aged 60 and above at baseline were included for analyses. Multilevel growth modeling was fitted to estimate the effects of neighborhood resources on frailty trajectories over a 7-year period, controlling for individual-level characteristics.ResultsOlder Chinese people who lived in neighborhoods with better basic infrastructures and a greater number of voluntary organizations were less frail at baseline. Accessible exercise facilities were associated with a lower initial level of frailty only among rural older adults, while higher community-level socioeconomic status (SES) was associated with a lower initial level of frailty only among urban older adults. Over the 7-year follow-up period, better basic infrastructures and accessible exercise facilities were associated with a slower increase rate of frailty scores among rural residents.Discussion and implicationsNeighborhood resources are important contributors to the level of frailty among older Chinese people. Our findings of significant urban-rural differences have important implications for designing and implementing infrastructure development and community building programs in rural and urban China.  相似文献   
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目的:观察理气中药经验组方对糖尿病大鼠胃排空延迟的干预作用。方法:雌雄各半成年SD大鼠110只,随机分为正常组(A组)、糖尿病中药组(B组)、糖尿病胃复安组(C组)、糖尿病组(D组)。A组、D组1次/d按10 mL/只予0.9%生理盐水灌胃,B组1次/d按8 mL/只予中药煎剂灌胃,C组1次/d按0.5 mg/只予胃复安片灌胃。喂养12周后,行13C胃排空实验及甲基橙水溶液胃排空实验,观察各组大鼠胃排空情况。结果:糖尿病大鼠胃排空较正常大鼠明显延迟(P0.01),糖尿病大鼠胃排空延迟模型制作成功。糖尿病中药组和糖尿病胃复安组大鼠胃排空较糖尿病组快(P0.01);糖尿病中药组大鼠胃排空较糖尿病胃复安组大鼠快(P0.05)。结论:常规喂养12周后糖尿病大鼠出现胃排空延迟。理气中药陈皮、枳实、木香、香附组方煎剂和胃复安均能促进糖尿病大鼠胃排空,理气中药组方煎剂的效果优于胃复安。  相似文献   
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Purpose

A hydrogel rectal spacer (HRS) is a medical device that is approved by the U.S. Food and Drug Administration to increase the separation between the prostate and rectum. We conducted a cost-effectiveness analysis of HRS use for reduction in radiation therapy (RT) toxicities in patients with prostate cancer (PC) undergoing external beam RT (EBRT).

Methods and Materials

A multistate Markov model was constructed from the U.S. payer perspective to examine the cost-effectiveness of HRS in men with localized PC receiving EBRT (EBRT alone vs EBRT + HRS). The subgroups analyzed included site of HRS placement (hospital outpatient, physician office, ambulatory surgery center) and proportion of patients with good baseline erectile function (EF). Data on EF, gastrointestinal and genitourinary toxicities incidence, and potential risks associated with HRS implantation were obtained from a recently published randomized clinical trial. Health utilities and costs were derived from the literature and the 2018 Physician Fee Schedule and were discounted 3% annually. Quality-adjusted life years (QALYs) and costs were modeled for a 5-year period from receipt of RT. Probabilistic sensitivity analysis and value-based threshold analyses were conducted.

Results

The per-patient 5-year incremental cost for spacers administered in a hospital outpatient setting was $3578, and the incremental effectiveness was 0.0371 QALYs. The incremental cost-effectiveness ratio was $96,440/QALY for patients with PC undergoing HRS insertion in a hospital and $39,286/QALY for patients undergoing HRS insertion in an ambulatory facility. For men with good baseline EF, the incremental cost-effectiveness ratio was $35,548/QALY and $9627/QALY in hospital outpatient and ambulatory facility settings, respectively.

Conclusions

Based on the current Medicare Physician Fee Schedule, HRS is cost-effective at a willingness to pay threshold of $100,000. These results contain substantial uncertainty, suggesting more evidence is needed to refine future decision-making.  相似文献   
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皮肤瘢痕是一个巨大的医学问题,每年约有1亿患者产生瘢痕。瘢痕的预防/治疗在很大程度上还没有得到满足的临床需求。瘢痕的形成通常是皮肤创伤的病理结果。而增生性瘢痕(hypertrophic scar,HTS)常发生在人深部损伤后。HTS通常被认为是组织收缩和过度的细胞外基质沉积的结果。肌成纤维细胞作为主要由成纤维细胞分化而来的效应细胞,在HTS的病理生理中起着至关重要的作用。多种生长因子、炎症因子参与了HTS发生的过程。目前,随着对HTS的深入探索和临床研究,各种创造性和有效的治疗方法正在萌芽。本文就HTS中西医形成机制研究进展进行综述,并针对其病理生理特点,对现有的中西医综合治疗方法进行综述。此外,我们进一步展望更适合的HTS中西医综合治疗的特色与方法。  相似文献   
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难治性胃食管反流病是临床疑难病,症状反复,缠绵难愈,治疗棘手。中医药治疗“反酸”“吞酸”证历久源远,充分挖掘古籍,深研病机,提炼治法,发挥中医药特色,对治疗本病意义深远。  相似文献   
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