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111.
112.
David M. Dickinson Dawn M. Dykstra Gregory N. Levine Shiqian Li James C. Welch Randall L. Webb 《American journal of transplantation》2005,5(4P2):850-861
The process of collecting and analyzing transplant data is complex. Familiarity with how these data are collected is crucial to a thorough understanding of the information. This article focuses on available OPTN-SRTR data and the continuing evolution of data collection mechanisms; how that data collection system is improving the data quality and reducing the data collection burden; how additional ascertainment of outcomes both completes and validates existing data; and caveats that remain for researchers. This year's article focuses further on research considerations related to cohort choice, timing of data submission, and potential biases in follow-up data. Ongoing improvements in data collection timeliness and scope are covered. The impact of extra ascertainment of outcomes, particularly for post-transplant kidney graft failure from Medicare data, are also examined. A section on graft failure reporting among different sources traces the steps by which the SRTR reconciles different data sources in its analyses. It is important that those reading and conducting transplant research understand the origin, structure, and scope of the available data. All of these issues should be carefully considered when choosing cohorts and data sources for analysis. 相似文献
113.
原发性单纯性脑干出血52例临床研究 总被引:1,自引:0,他引:1
目的研究原发性单纯性脑干出血的病因、诊断、治疗、预后及预防。方法对52例原发性单纯性脑干出血的临床资料进行回顾性分析。结果预后良好25例,优良率为48.1%;死亡21例,死亡率40.4%;出血量≤5.0ml死亡率21.9%(7/32),出血量≥5.1ml死亡率70.0%(14/20),出血量〉10.0ml 10例全部死亡。结论原发性单纯性脑干出血发病急,病情重,死亡率高,预后差;高血压为本病的主要发病原因;CT是原发性单纯性脑干出血的安全、可靠诊断方法;适时进行气管切开及亚低温治疗能有效提高疗效及降低死残率;严格控制血压是预防原发性单纯性脑干出血的重要措施。 相似文献
114.
115.
Analysis of count data from clinical trials using mixed effect analysis has recently become widely used. However, algorithms
available for the parameter estimation, including LAPLACE and Gaussian quadrature (GQ), are associated with certain limitations,
including bias in parameter estimates and the long analysis runtime. The stochastic approximation expectation maximization
(SAEM) algorithm has proven to be a very efficient and powerful tool in the analysis of continuous data. The aim of this study
was to implement and investigate the performance of a new SAEM algorithm for application to count data. A new SAEM algorithm
was implemented in MATLAB for estimation of both, parameters and the Fisher information matrix. Stochastic Monte Carlo simulations
followed by re-estimation were performed according to scenarios used in previous studies (part I) to investigate properties
of alternative algorithms (Plan et al., 2008, Abstr 1372 []). A single scenario was used to explore six probability distribution models. For parameter estimation, the relative bias
was less than 0.92% and 4.13% for fixed and random effects, for all models studied including ones accounting for over- or
under-dispersion. Empirical and estimated relative standard errors were similar, with distance between them being <1.7% for
all explored scenarios. The longest CPU time was 95 s for parameter estimation and 56 s for SE estimation. The SAEM algorithm
was extended for analysis of count data. It provides accurate estimates of both, parameters and standard errors. The estimation
is significantly faster compared to LAPLACE and GQ. The algorithm is implemented in Monolix 3.1, (beta-version available in
July 2009). 相似文献
116.
117.
Data Bank and Consulting System for Medical Management of Patiens with Acute Radiation Sickness 总被引:1,自引:1,他引:0 下载免费PDF全文
Tang Zhongming Ye Genyao Mao Bingzhi Luo Qingliang Wang Guilin Liu Xiuwen Lin Ke Wu Dechang 《中华放射医学与防护杂志》1995,15(5):306-310
DataBankandConsultingSystemforMedicalManagementofPatienswithAcuteRadiationSickness¥TangZhongming;YeGenyao;MaoBingzhi;LuoQingl... 相似文献
118.
Carlton K. Erickson 《Alcoholism, clinical and experimental research》1996,20(6):1138-1139
Over the past 10 years, I have been privileged to conduct educational forums for audiences containing many recovering alcoholics or otherwise chemically dependent persons. In these forums about the addictive diseases and their treatment and research possibilities, significant interaction with the audience members occurs. During these interactions, certain anecdotal phenomena seem to predominate. The repetitive nature of these reports suggests the need for systematic investigation. As with editorial comments in major medical journals, observed phenomena and unanswered questions from those afflicted can be valuable in the generation of testable hypotheses. Perhaps the ideas presented herein will be useful in the development of future research on alcohol abuse and alcohol dependence. 相似文献
119.
Tesio L. Gamba C. Capelli A. Franchignoni F. P. 《The Italian Journal of Neurological Sciences》1995,16(6):473-477
Rehabilitation is under-represented in the neurological literature on disabling diseases. A Medline search was conducted to retrieve the articles published between January 1991 and June 1994 under the main headings of Stroke, Parkinson's disease, Multiple sclerosis, Brain injury, Ataxia and Dementia. These were then combined with the sub-heading Rehabilitation. The former search yielded 27724 articles, the latter 1272 (4.6%). In 1992, the Journal of Citation Reports (JCR) assigned to Journals publishing rehabilitation papers an average Impact Factor (IF) of 0.7–2.8 (median 1.8): that is, 31–90% (depending on the various main headings, median 68%) of the average IF given to Journals publishing non-rehabilitation papers. In the present study, the weight of the literature was defined as the product of the number of articles multiplied by the IF of the corresponding Journal (IF=0 for non-JCR Journals). Across the various neurologic conditions, the weight of the Rehab literature was 0.1–7% (median 2%) of the weight of the non-Rehab literature. The results suggest that neurology is still reluctant to face the disability challenge.
Sommario La riabilitazione è scarsamente rappresentata nella letteratura neurologica sulle patologie che causano disabilità. Gli Autori hanno interrogato la banca-dati Medline nella ricerca degli articoli pubblicati fra il Gennaio 1991 ed il Giugno 1994 sotto le parole-chiave Stroke, Parkinson's disease, Multiple Sclerosis, Brain injury, Ataxia e Dementia. È stato poi eseguito un incrocio con la parola-chiave secondaria Riabilitazione.La prima ricerca ha prodotto 27724 articoli mentre la seconda ne ha prodotti 1272 (4.6%). Nel 1992 il Journal of Citation Reports (JCR) ha attribuito alle Riviste che hanno pubblicato articoli con tema riabilitativo un Impact Factor (IF) medio di 0.7–2.8 (mediana 1.8), pari al 31–90% (a seconda della parola-chiave principale: mediana delle percentuali 68%) dell'IF medio attribuito alle Riviste che hanno pubblicato soltanto articoli su temi non riabilitativi. In questo studio è stato definito come peso della letteratura il prodotto del numero di articoli per l'IF delle rispettive Riviste (IF=0 per le Riviste non censite dal JCR). A seconda delle diverse patologie neurologiche, il peso della letteratura riabilitativa variava fra 0.1 e 7% (mediana 2%) del peso della letteratura non riabilitativa.I risultati suggeriscono che la Neurologia sia ancora riluttante ad affrontare la sfida che le pone la disabilità.相似文献
120.
槐耳的研制及临床应用 总被引:4,自引:0,他引:4
槐耳是一种人药1500余年但已湮没300余年的重要药用真菌。它和其原料药材槐耳菌质近年来已被批准为中药国家一类新药,就有关槐耳的研制及其在肿瘤疾病方面的应用作一综述。 相似文献