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31.
目的:综述药品价格指数的研究方法,为药品价格指数实证研究提供方法学借鉴。方法:以近年来的国内外研究文献为基础,从指数方法(公式)、药品产品的定义、价格和数量计量单位三个方面进行综述,并对选择不同方法的优缺点以及测量偏倚进行评析。结果:价格指数的结果会随着指数公式所选择的权重、产品的定义以及价格和数量计量单位的不同而不同。在指数公式的选择中是否考虑了新产品上市和老产品退市的产品更新换代问题以及产品的质量变化问题等同样会使得指数结果具有较大差异。结论:药品价格指数的研究方法还有待进一步研究完善,学术界应致力于对价格指数进行更深入的研究,以达到更精确的测量。在实证分析中尽可能采用多种方法进行计算,以更加准确地反映药品价格水平的变化。  相似文献   
32.
目的:建立多西他赛注射液溶剂中乙醇含量的气相色谱测定方法。方法:气相色谱法:毛细管色谱柱;载气:氮气;检测器:氢火焰离子化检测器;起始温度为50℃,维持10min,再以每分钟10℃的速率升温至110℃;进样口温度:190℃;检测器温度:220℃;柱流量:3.2ml/min;进样量:1μl。结果:定量限、检测限、溶液稳定性、线性、耐用性、重复性、进样精密度经验证,结果均良好。结论:本法可用于多西他赛注射液溶剂中乙醇含量的测定。  相似文献   
33.
The system of biographies in the French Communist Party was a system for evaluating and selecting militants. It was really put in place only thanks to the action of one man, the prototype of the Bolshevik, “à la française”. Born in 1900, son of a customs officer who died of alcohol and a farmer. Tuberculous, he becomes a waiter and adheres to communism. With a brawling temperament, he is also noted by the local PCF leadership for his organizational skills. Regularly imprisoned, he was called by the national leadership of the PCF to reorganize the PCF in the regions and then in Paris. Sent to the best training place for a communist, the International Leninist School, he learned the techniques of going underground and the workings of the Soviet model party. On his return to France, he applied his methods to the functioning of the PCF and imported the new biographical questionnaire. Analysis of the questionnaires shows that in the name of fear of police infiltration and heterodoxy, an extremely thorough control system of militant personnel has been developed. Tréand's entire character led him to misinterpret the new line of the Communist International, which led to his political downfall and death in 1949.  相似文献   
34.
BackgroundThe health impact of antimicrobial resistance (AMR) has not been included in the Global Burden of Disease (GBD) report, as reliable data have been lacking. AMR burden estimates have been derived from models combining incidence and/or prevalence data from national and/or international surveillance systems and mortality estimates from clinical studies. Depending on utilized empirical data, statistical methodology and applied endpoints, the validity and reliability of results can differ substantially.ObjectivesWe assessed comprehensiveness, and internal and external validity of studies estimating the clinical impact of infections caused by the priority antibiotic resistant pathogens monitored by the WHO Global Antimicrobial Resistance Surveillance System.Data sourcesOvid MEDLINE, January 1950 to March 2019, In-Process and other non-indexed citations were searched.Study eligibility criteriaStudies reporting mortality, length of hospital stay, duration of the disease until remission and/or death, complications, hospital re-admissions, and follow-up beyond hospital discharge were eligible.MethodsThe literature was searched according to the Cochrane recommendations and reported according to Preferred Reporting Items for Systematic Reviews.ResultsTwo-hundred and eighty-six studies out of 3529 were eligible. Studies derived mainly from high-income countries (215, 75%) and relied on data from retrospective (226, 79%), single-centre (201, 70%), cohort studies (243, 85%). The health impact was mostly limited to all-cause mortality (128, 45%) with heterogeneity in timing of assessment; attributable length of hospital stay was seldom adjusted for pre-infection admission time and a few studies had enough follow-up for assessing long-term sequelae. Overall, adjustment for confounding has shown a substantial improvement. Data on health state definitions and duration of diseases are generally lacking, precluding calculation of disability-adjusted life years, critical for application of the GBD study methodology.ConclusionEfforts to improve harmonization, representativeness, quality of AMR surveillance data and cohort studies to determine AMR attributable mortality and morbidity are urgently required. Policy makers need accurate and detailed burden estimates to inform prioritization of resource allocation, and to select the most effective intervention strategies to halt the AMR crisis.  相似文献   
35.
This article is the second of a series of 2 educational articles. In the first article, we described the basic concepts of survival analysis, summarizing the common statistical methods and providing a set of recommendations to guide the strategy of survival analyses in randomized clinical trials and observational studies. Here, we introduce stratified Cox models and frailty models, as well as the immortal time bias arising from a poor assessment of time-dependent variables. To address the issue of multiplicity of outcomes, we provide several modelling strategies to deal with other types of time-to-event data analyses, such as competing risks, multistate models, and recurrent-event methods. This review is illustrated with examples from previous cardiovascular research publications, and each statistical method is discussed alongside its main strengths and limitations. Finally, we provide some general observations about alternative statistical methods with less restrictive assumptions, such as the win ratio method, the restrictive mean survival time, and accelerated failure time model.  相似文献   
36.
Atherosclerosis(ATH) and non-alcoholic fatty liver disease(NAFLD) are medical conditions that straddle a communal epidemiology, underlying mechanism and a clinical syndrome that has protean manifestations, touching every organ in the body. These twin partners, ATH and NAFLD, are seemingly straightforward and relatively simple topics when considered alone, but their interdependence calls for more thought. The study of the mutual relationship of NAFLD and ATH should involve big data analytics approaches, given that they encompass a constellation of diseases and are related to several recognized risk factors and health determinants and calls to an explicit theory of change, to justify intervention. Research studies on the "association between aortic stiffness and liver steatosis in morbidly obese patients", published recently, sparsely hypothesize new mechanisms of disease, claiming the "long shadow of NAFLD"as a risk factor, if not as a causative factor of arterial stiffness and ATH. This statement is probably overreaching the argument and harmful for the scientific credence of this area of medicine. Despite the verification that NAFLD and cardiovascular disease are strongly interrelated, current evidence is that NAFLD may be a useful indicator for flagging early arteriosclerosis, and not a likely causative factor. Greater sustainable contribution by precision medicine tools, by validated bioinformatics approaches, is needed for substantiating conjectures,assumptions and inferences related to the management of big data and addressed to intervention for behavioral changes within an explicit theory of change.  相似文献   
37.
38.
Abstract

Background and Objectives: The purpose of this survey study was to examine the prevalence and intensity of pain and associated patient characteristics in a national sample of veterans with paraplegia. Of particular interest were upper limb (UL) pain conditions, which pose unique challenges to individuals who use a wheelchair for mobility. Because the risk for UL pain conditions appears to increase over time, the associations among age, duration of wheelchair use, and UL pain were evaluated.

Methods: A group of 1 ,6 7 5 individuals between the ages of 1 8 and 65 with a lesion between T2 and L2 and a mailing address on file were selected randomly from the Veteran's Affairs Spinal Cord Dysfunction Registry and mailed a survey packet. Of the deliverable packets, -46% were completed and returned.

Results: Approximately 81% of the respondents reported at least a minimal Ievei of ongoing unspecified pain and 69'7'o experienced current UL pain. Shoulder pain intensity was most severe du ring the performance of wheelchair-related mobility and transportation activities, suggesting that UL pain may have a significant impact on functional independence. Duration of wheelchair use modestly predicted shoulder pain prevalence and intensity, but age and the interaction between age and duration of wheelchair use did not.

Condusion: The data of the present study suggest that the development, persistence, and exacerbation of UL pain conditions in persans with paraplegia aremultidimensional processes. A comprehensive theoretic model is needed to integrate the existing empiric Iiterature in this area.  相似文献   
39.
Robertson, North, and Geggie (1992) have suggested that the voluntary activation of the left upper limb in the left hemispace (spatio-motor cueing) could reduce unilateral neglect. This study assesses the efficacy of visuo-spatio-motor cueing, and particularly the generalisation to daily-life activities, in two patients with very severe neglect who had failed to improve with scanning training. The patients were included in the trial 4 and 7 months after a severe unilateral right hemispheric stroke. They both suffered from disabling unilateral neglect despite intensive conventional therapy. A single-case experimental ABAB design was used (A = baseline with conventional treatment; B = visuo-spatio-motor cueing; each period = 2 weeks). A randomisation test was used to assess the presence of a specific therapeutic effect. In both cases, there was a statistically significant treatment-related improvement on a line bisection test. A parallel improvement was found on neglect behaviourin daily life, as assessed by the Catherine Bergego Scale (Azouvi et al., 1996). The therapeutic effect was maintained at 1-month follow up. These results suggest that visuo-spatio-motor cueing may be efficient in very severe neglect and may help in obtaining generalisation to daily-life activities.  相似文献   
40.
BackgroundPriority setting and resource allocation in health care, surveillance and interventions is based increasingly on burden of disease. Several methods exist to calculate the non-fatal burden of disease of burns expressed in years lived with disability (YLDs). The aim of this study was to assess the burden of disease due to burns in Western Australia 2011–2018 and compare YLD outcomes between three existing methods.MethodsData from the Burns Service of Western Australia was used. Three existing methods to assess YLDs were compared: the Global Burden of Disease (GBD) method, a method dedicated to assess injury YLDs (Injury-VIBES), and a method dedicated to assess burns YLDs (INTEGRIS-burns).ResultsIncidence data from 2,866 burn patients were used. Non-fatal burden of disease estimates differed substantially between the different methods. Estimates for 2011–2018 ranged between 610 and 1,085 YLDs per 100.000 based on the Injury-VIBES method; between 209 and 324 YLDs based on the INTEGRIS-burns method; and between 89 and 120 YLDs based on the GBD method. YLDs per case were three to nine times higher when the Injury-VIBES method was applied compared to the other methods. Also trends in time differed widely through application of the different methods. There was a strong increase in YLDs over the years when the Injury-VIBES method was applied, a slight increase when the INTEGRIS-burns method was applied and a stable pattern when the GBD method was applied.ConclusionThis study showed that the choice for a specific method heavily influences the non-fatal burden of disease expressed in YLDs, both in terms of annual estimates as well as in trends over time. By addressing the methodological limitations evident in previously published calculations of the non-fatal burden of disease, the INTEGRIS-burns seems to present a method to provide the most robust estimates to date, as it is the only method adapted to the nature of burn injuries and their recovery.  相似文献   
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