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Assoc. Prof. Dr. Andrea Wichelhaus Richard Haas Franz-Günter Sander Joachim-Franz Kreidler 《Journal of orofacial orthopedics》1998,59(6):340-351
For functional rehabilitation and improvement of mandibular mobility, 14 patients with dislocated collum or collum fracture dislocations were treated with a spring activator after surgical-conservative treatment. With an interincisal distance of<12 mm, therapy was started with a loop spring. The average age of the patients was 26.6 years. Eight patients showed additional traumatic injuries, 2 patients were seriously polytraumatically injured. The clinical investigations referring to the maximum mouth opening and maximal interincisal distance resulted in a good to very good functional rehabilitation in all cases. The average maximal interincisal distance of 31.7 mm at the beginning of the spring activator therapy could be increased to 47.3 mm. The largest increase of the maximal interincisal distance was observed after 4 weeks of therapy. The type of reaction, however, differed interindividually. Three patients showed a spontaneous improvement of the interincisal distance within the first 2 to 3 weeks of removal of intermaxillary fixation, whereas 7 patients whowed no improvement or only slightly improved values until insertion of the spring activator. An enlargement of the interincisal distance could be achieved in almost every patient within a relatively short period of time despite a drastically reduced mouth opening. Consequently, because of its mode of action in the form of a neuromuscular influence, the spring activator is especially suitable for the functional rehabilitation of patients with fractures of the condylar process. 相似文献
3.
Sander Greenland 《Statistics in medicine》1993,12(8):717-736
Many epidemiologic investigations are designed to study the effects of multiple exposures. Most of these studies are analysed either by fitting a risk-regression model with all exposures forced in the model, or by using a preliminary-testing algorithm, such as stepwise regression, to produce a smaller model. Research indicates that hierarchical modelling methods can outperform these conventional approaches. I here review these methods and compare two hierarchical methods, empirical-Bayes regression and a variant I call ‘semi-Bayes’ regression, to full-model maximum likelihood and to model reduction by preliminary testing. I then present a simulation study of logistic-regression analysis of weak exposure effects to illustrate the type of accuracy gains one may expect from hierarchical methods. Finally, I compare the performance of the methods in a problem of predicting neonatal mortality rates. Based on the literature to date, I suggest that hierarchical methods should become part of the standard approaches to multiple-exposure studies. 相似文献
4.
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Raph Hamers Sander Bontemps Marjan van den Akker Ruy Souza Júlio Penaforte Niels Chavannes 《Primary care respiratory journal》2006,15(5):299-306
AIMS: The developing world is particularly at risk of an increasing health burden due to an increased prevalence of Chronic Obstructive Pulmonary Disease (COPD) secondary to increasing tobacco consumption. However, research is scarce. The objectives of this study were to assess the current competence for diagnosing COPD in primary care in a resource-limited setting in Brazil, and to develop a local patient profile for case-finding. METHODS: 34 general practitioners (GPs) in five areas of northern Brazil recruited adult patients with principal complaints of cough and/or shortness of breath who then had spirometry (n = 142). RESULTS: For the dichotomous variable 'COPD' the degree of agreement between GP diagnosis (n = 64, 18.3%) and spirometric outcome (n = 36, 25.4%) was poor, with Kappa = 0.055 (SE 0.087) and DOR = 1.35. False-positive and false-negative diagnosis proportions were 19.8% and 75%, respectively. Independent risk factors were 'smoking history of more than five pack years' and 'presence of both dyspnoea and cough'. It requires the testing of 2.2 smokers with more than five pack years to detect one patient at risk. CONCLUSIONS: COPD is a common yet underdiagnosed disease in Brazilian primary care. Spirometry improves diagnostic competence and case-finding substantially. If applied in a pre-selected high-risk population, we believe spirometry can be a cost-effective diagnostic tool for case-finding in the resource-limited setting. This study provides important baseline information for effective guideline implementation. 相似文献
6.
Intravenous captopril in congestive heart failure 总被引:1,自引:0,他引:1
S Ahmad T D Giles L E Roffidal Y Haney M B Given G E Sander 《Journal of clinical pharmacology》1990,30(7):609-614
Hemodynamic and neurohumoral effects of intravenous captopril were studied in ten patients with severe chronic congestive heart failure (NYHA Functional Class III and IV). Incremental bolus doses of captopril, titrated to a maximum cumulative dose of 15 mg, were given at 10-minute intervals. Systemic arterial pressure, mean pulmonary capillary wedge pressure, systemic vascular resistance, mean pulmonary artery pressure, and heart rate decreased (P less than .05). Cardiac index and stroke volume index increased (P less than .05). Maximum hemodynamic effects occurred after cumulative doses of 7 mg and were seen within 30 minutes after initiation of therapy; responses persisted for 30-90 minutes after the last dose. Plasma renin activity increased, and plasma atrial natriuretic factor concentration decreased. No adverse effects were observed with the use of intravenous captopril. Thus, intravenous captopril produces rapid and favorable hemodynamic improvement in advanced heart failure patients. 相似文献
7.
We describe a case of a traumatic aneurysm of the cavernous portion of the internal carotid artery in a patient who had had craniofacial trauma 12 years before. MR and CT revealed a mass in the sphenoid sinus thought to be unrelated to the patient''s symptoms. Carotid angiography gave the correct diagnosis. 相似文献
8.
9.
Sander P. G. Frankema Michael J. R. Edwards Ewout W. Steyerberg Arie B. van Vugt 《European Journal of Trauma》2002,28(6):355-364
Background: Evaluating the performance of a trauma system may be attempted by comparing outcome in different trauma populations. Controlling
for injury severity is a necessity for such evaluations. We compare two current models for doing so: the “Trauma and Injury
Severity Score” (TRISS) and “A Severity Characterization Of Trauma” (ASCOT).
Material and Methods: This study of high-energy trauma victims took place in Leiden, the Netherlands, between 1993 and 1998. Using the Hosmer-Lemeshow
(HL) test and receiver operator characteristic (ROC) analysis, the TRISS and ASCOT models were compared for calibration and
discrimination.
Results: 1,024 patients, with an average Injury Severity Score (ISS) of 13.5, were eligible for inclusion. Blunt trauma was the predominant
cause of injuries. Both models gave accurate, though pessimistic, results in predicting the actual number of fatalities (n
= 71). The HL test indicated a sufficient fit for the ASCOT model (p = 0.28) and an insufficient fit (p = 0.02) for TRISS.
The ROC curves were nearly identical (0.97). Including age as a linear variable, instead of using the current age groups,
resulted in an improved discriminative power of the models.
Conclusions: The ASCOT model proved superior over TRISS in its accuracy to estimate of survival chances. This difference was most evident
for victims with an estimated survival chance of 60–90%. Future national trauma researchers should therefore collect ASCOT
data. Improved ASCOT models could be developed, with age as a linear variable.
Received: April 25, 2002; revision accepted: September 17, 2002
Correspondence Address Prof. Arie B. van Vugt, MD, PhD, Department of General Surgery and Traumatology, Erasmus MC Rotterdam, Dr. Molewaterplein
40, Postbus 2040, 3000 CA Rotterdam, The Netherlands, Phone (+31/10) 463-5735, Fax -4757, e-mail: vanvugt@hlkd.azr.nl 相似文献
10.
Priv.-Doz. Dr. M. Raulf-Heimsoth H.-P. Rihs I. Sander R. Merget T. Brüning 《Trauma und Berufskrankheit》2004,6(2):140-143
As a consequence of AIDS prevention strategies, the use of powdered disposable latex gloves in hospitals and private medical practices has increased conspicuously in the past 10 years, and allergic reactions to natural latex have become a frequently observed problem. The clinical picture of type I allergies (immediate hypersensitivity) to natural latex ranges from slight, local allergic symptoms (urticaria, rhinitis, and conjunctivitis) to asthmatic complaints up to severest anaphylactic reactions. In addition to health care employees, patients are being affected with an increasing tendency during a variety of surgical and other medical interventions. Due to its enormous hygienic and economic significance, natural latex has become one of the most frequently studied sources of allergies. Efforts were undertaken to identify the causes and triggering factors, to develop diagnostic tools and continue to improve upon them, and to establish preventive measures and implement them successfully. 相似文献