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Zeitschrift für Psychodrama und Soziometrie - Dieser Beitrag der Zeitschrift für Psychodrama und Soziometrie zeigt auf, wie die Corona-Pandemie und ihre Begleiterscheinungen das... 相似文献
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Diegritz Christian Manhart Jürgen Bücher Katharina Grabein Béatrice Schuierer Günther Kühnisch Jan Kunzelmann Karl-Heinz Hickel Reinhard Fotiadou Christina 《Clinical oral investigations》2020,24(8):2931-2941
Clinical Oral Investigations - The corona disease (COVID-19) is developing into one of the greatest challenges for healthcare professionals around the world. In this article, we report the detailed... 相似文献
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Regina Stegherr Arthur Allignol Reinhard Meister Christof Schaefer Jan Beyersmann 《Statistics in medicine》2020,39(4):481-493
Both delayed study entry (left-truncation) and competing risks are common phenomena in observational time-to-event studies. For example, in studies conducted by Teratology Information Services (TIS) on adverse drug reactions during pregnancy, the natural time scale is gestational age, but women enter the study after time origin and upon contact with the service. Competing risks are present, because an elective termination may be precluded by a spontaneous abortion. If left-truncation is entirely random, the Aalen-Johansen estimator is the canonical estimator of the cumulative incidence functions of the competing events. If the assumption of random left-truncation is in doubt, we propose a new semiparametric estimator of the cumulative incidence function. The dependence between entry time and time-to-event is modeled using a cause-specific Cox proportional hazards model and the marginal (unconditional) estimates are derived via inverse probability weighting arguments. We apply the new estimator to data about coumarin usage during pregnancy. Here, the concern is that the cause-specific hazard of experiencing an induced abortion may depend on the time when seeking advice by a TIS, which also is the time of left-truncation or study entry. While the aims of counseling by a TIS are to reduce the rate of elective terminations based on irrational overestimation of drug risks and to lead to better and safer medical treatment of maternal disease, it is conceivable that women considering an induced abortion are more likely to seek counseling. The new estimator is also evaluated in extensive simulation studies and found preferable compared to the Aalen-Johansen estimator in non–misspecified scenarios and to at least provide for a sensitivity analysis otherwise. 相似文献
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Hemoglobin,alkalic phosphatase,and C‐reactive protein predict the outcome in patients with liposarcoma 下载免费PDF全文
Joannis Panotopoulos Florian Posch Benjamin Alici Philipp Funovics Christoph Stihsen Gabriele Amann Thomas Brodowicz Reinhard Windhager Cihan Ay 《Journal of orthopaedic research》2015,33(5):765-770
Data on prognostic biomarkers in soft tissue sarcomas are scarce. The aim of the study was to define prognostic markers in patients with a liposarcoma, a subtype of sarcoma derived from adipose tissue. We restrospectively reviewed 85 patients with liposarcoma treated at our department from May 1994 to October 2011. Kaplan–Meier curves, uni‐, and multivariable Cox proportional hazard models and competing risk analysis were performed to evaluate the association between putative biomarkers with disease‐specific and overall survival. We observed a significant association between both alkalic phosphatase (ALP; subhazard ratio [SHR] per 1 unit increase: 1.35; 95%CI 1.10–1.65; p = 0.005) and C‐reactive protein (CRP; SHR per 1 mg/dl increase: 2,57; 95%CI 1.36–4,86; p = 0.004) with disease‐specific survival. Hemoglobin (Hb) (HR per 1 g/dl increase: 065; 95%CI 0.48–0.87; p = 0.003) was associated with overall survival. These associations prevailed after multivariable adjustment for AJCC tumor stage. This study identifies CRP and ALP as novel independent predictors of disease‐specific survival in patients with liposarcoma. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:765–770, 2015. 相似文献
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Hickel R Kaaden C Paschos E Buerkle V García-Godoy F Manhart J 《American journal of dentistry》2005,18(3):198-211
PURPOSE: To compile a survey of the longevity and reasons for failure of stainless steel crowns, amalgam, glass-ionomer, composite and compomer restorations in stress-bearing cavities of primary molars. METHODS: This work reviewed the dental literature of 1971 up to July 2003 for longitudinal, controlled clinical studies and retrospective cross-sectional studies. Only studies investigating the clinical performance of restorations in primary teeth with an observation period of at least 2 years were included. Annual failure rates of stainless steel crowns, amalgam, glass-ionomer, composite and compomer restorations were determined and failure reasons were discussed. RESULTS: Annual failure rates in stress-bearing cavities of primary molars were determined to be: 0-14% for stainless steel crowns, 0-35.3% for amalgam restorations, 0-25.8% for glass-ionomer restorations, 2-29.1% for atraumatic restorative treatments, 0-15% for composite restorations, and 0-11 for compomer restorations. Main reasons for failure were secondary caries, marginal deficiencies, fracture, and wear. 相似文献