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61.
Beier US Grunert I Kulmer S Dumfahrt H 《The International journal of prosthodontics》2007,20(3):270-274
PURPOSE: This study aimed to evaluate the clinical success of a hydrophilic polyvinyl siloxane impression material for fixed dental restorations under various clinical conditions. MATERIALS AND METHODS: A total of 1,466 preparations for fixed restorations in maxillary and mandibular anterior and posterior teeth were evaluated. The study contained inlay, onlay, crown, veneer, post, and adhesive-wing preparations and implants for gold, porcelain-fused-to-metal, and ceramic restorations. The preparation finish line relative to the crest of the marginal gingiva, type of restoration, and position of the teeth were recorded. Three categories were established to rate impression quality: perfect impressions, with an absence of any voids or bubbles and perfect reproduction of the preparation finish line, were rated Criteria I; acceptable impressions, with minimal defects (< or = 2 mm) not involving the preparation finish line, were rated Criteria II; and unacceptable impressions, with larger voids or bubbles (> 2 mm) or defects involving the preparation finish line, were rated Criteria III. RESULTS: Overall, 96.86% of the final impressions were clinically acceptable, 89.43% of which were rated Criteria I and 7.43% of which were rated Criteria II. Only 3.14% of the impressions were unacceptable and rated Criteria III. A significant influence on impression quality was found when the preparation finish line was more than 2 mm subgingival (P < .004), as well as when a beveled preparation was used (P < .004). The position of the teeth (P > .404) had no significant effect. CONCLUSION: Surface-activated polyvinyl siloxane impression material offers high predictability to avoid bubbles and voids in the final impression. 相似文献
62.
Meyer Carsten H. Szurman Peter Haritoglou Christos Maier Mathias Wolf Armin Lytvynchuk Lyubomyr Priglinger Siegfried Hillenkamp Jost Wachtlin Joachim Becker Matthias Mennel Stefan Koss Michael J. 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2020,258(10):2151-2161
Graefe's Archive for Clinical and Experimental Ophthalmology - Persisting macular holes (PMH) after surgical release of any epiretinal traction of the vitreous and adjacent membrane may rely on... 相似文献
63.
Katharina Rifai Selam W. Habtegiorgis Caroline Erlenwein Siegfried Wahl 《Journal of vision》2020,20(13)
Spatially varying distortions (SVDs) are common artifacts of spectacles like progressive additional lenses (PALs). To habituate to distortions of PALs, the visual system has to adapt to distortion-induced image alterations, termed skew adaptation. But how this visual adjustment is achieved is largely unknown. This study examines the properties of visual adaptation to distortions of PALs in natural scenes. The visual adaptation in response to altered form and motion features of the natural stimuli were probed in two different psychophysical experiments. Observers were exposed to distortions in natural images, and form and motion aftereffects were tested subsequently in a constant stimuli procedure where subjects were asked to judge the skew, or the motion direction of an according test stimulus.Exposure to skewed natural stimuli induced a shift in perceived undistorted form as well as motion direction, when viewing distorted dynamic natural scenes, and also after exposure to static distorted natural images. Therefore, skew adaptation occurred in form and motion for dynamic visual scenes as well as static images. Thus, specifically in the condition of static skewed images and the test feature of motion direction, cortical interactions between motion-form processing presumably contributed to the adaptation process.In a nutshell, interfeature cortical interactions constituted the adaptation process to distortion of PALs. Thus, comprehensive investigation of adaptation to distortions of PALs would benefit from taking into account content richness of the stimuli to be used, like natural images. 相似文献
64.
Verena J. Koller Volker Auwärter Tamara Grummt Bjoern Moosmann Miroslav Mišík Siegfried Knasmüller 《Toxicology and applied pharmacology》2014
Cannabicyclohexanol (CP-47,497-C8) is a representative of a group of cannabimimetic cyclohexylphenols which is added to herbal mixtures as a cannabis substitute since 2008. Although in the beginning CP-47,497-C8 was the main ingredient of “Spice” and similar products, it was partly replaced by aminoalkylindole-type cannabinoid receptor agonists like JWH-018, JWH-073 or JWH-250, but never completely disappeared from the market. Since information on its toxicological properties is scarce, we investigated the effects of the drug in human derived cell lines. The cytotoxic effects were studied in a panel of assays (SRB, XTT, LDHe and NR tests) in a buccal derived (TR146) and a liver derived (HepG2) cell line. The strongest effects were seen in the two former assays at levels ≥ 7.5 μM indicating that the compound interferes with protein synthesis and causes membrane damage. In additional comet assays, DNA damage was detected at levels ≥ 10 μM. Experiments with lesion specific enzymes showed that these effects are not due to oxidative damage of DNA bases. The negative findings obtained in Salmonella/microsome assays and the positive results of micronucleus tests with the cell lines indicate that the compound does not cause gene mutations but acts on the chromosomal level. In contrast to other synthetic cannabinoids, no indication for estrogenic/antiestrogenic properties was seen in a luciferase assay with bone marrow derived U2-OS cells. In conclusion, our findings show that the drug has only weak cytotoxic properties. However, the induction of chromosomal damage indicates that it may cause adverse effects in users due to its impact on the stability of the genetic material. 相似文献
65.
66.
Hanna Kaduszkiewicz Marion Eisele Birgitt Wiese Jana Prokein Melanie Luppa Tobias Luck Frank Jessen Horst Bickel Edelgard M?sch Michael Pentzek Angela Fuchs Sandra Eifflaender-Gorfer Siegfried Weyerer Hans-Helmut K?nig Christian Brettschneider Hendrik van den Bussche Wolfgang Maier Martin Scherer Steffi G. Riedel-Heller The Study on Aging Cognition Dementia in Primary Care Patients Study Group 《Annals of family medicine》2014,12(2):158-165
PURPOSE
The concept of mild cognitive impairment (MCI) has recently been introduced into the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) as mild neurocognitive disorder, making it a formal diagnosis. We investigated the prognostic value of such a diagnosis and analyzed the determinants of the future course of MCI in the AgeCoDe study (German Study on Ageing, Cognition, and Dementia in Primary Care Patients).METHODS
We recruited 357 patients with MCI aged 75 years or older from primary care practices and conducted follow-up with interviews for 3 years. Depending on the course of impairment over time, the patients were retrospectively split into 4 groups representing remittent, fluctuating, stable, and progressive courses of MCI. We performed ordinal logistic regression analysis and classification and regression tree (CART) analysis.RESULTS
Overall, 41.5% of the patients had remission of symptoms with normal cognitive function 1.5 and 3 years later, 21.3% showed a fluctuating course, 14.8% had stable symptoms, and 22.4% had progression to dementia. Patients were at higher risk for advancing from one course to the next along this spectrum if they had symptoms of depression, impairment in more than 1 cognitive domain, or more severe cognitive impairment, or were older. The result on a test of the ability to learn and reproduce new material 10 minutes later was the best indicator at baseline for differentiating between remittent and progressive MCI. Symptoms of depression modified the prognosis.CONCLUSIONS
In primary care, about one-quarter of patients with MCI have progression to dementia within the next 3 years. Assessments of memory function and depressive symptoms are helpful in predicting a progressive vs a remittent course. When transferring the concept of MCI into clinical diagnostic algorithms (eg, DSM-5), however, we should not forget that three-quarters of patients with MCI stayed cognitively stable or even improved within 3 years. They should not be alarmed unnecessarily by receiving such a diagnosis. 相似文献68.
Bernhard Hametner Siegfried Wassertheurer Alun D. Hughes Kim H. Parker Thomas Weber Bernd Eber 《International journal of cardiology》2014
Background
Analysis of the arterial pressure curve plays an increasing role in cardiovascular risk stratification. Measures of wave reflection and aortic stiffness have been identified as independent predictors of risk. Their determination is usually based on wave propagation models of the circulation. Another modeling approach relies on modified Windkessel models, where pressure curves can be divided into reservoir and excess pressure. Little is known of their prognostic value.Methods and results
The aim of this study is to evaluate the predictive value of parameters gained from reservoir theory applied to aortic pressure curves in a cohort of high-risk patients. Furthermore the relation of these parameters to those from wave separation analysis is investigated.Central pressure curves from 674 patients with preserved ejection fraction, measured by radial tonometry and a validated transfer function, were analyzed. A high correlation between the amplitudes of backward traveling pressure waves and reservoir pressures was found (R = 0.97). Various parameters calculated from the reservoir and excess pressure waveforms predicted cardiovascular events in univariate Cox proportional hazards modeling. In a multivariate model including several other risk factors such as brachial blood pressure, the amplitude of reservoir pressure remained a significant predictor (HR = 1.37 per SD, p = 0.016).Conclusions
Based on very different models, parameters from reservoir theory and wave separation analysis are closely related and can predict cardiovascular events to a similar extent. Although Windkessel models cannot describe all of the physiological properties of the arterial system, they can be useful to analyze its behavior and to predict cardiovascular events. 相似文献69.
70.
Tanja Djurdjevic MD Alexander Loizides MD Wolfgang Löscher MD Hannes Gruber MD Michaela Plaikner MD Siegfried Peer MD 《Muscle & nerve》2014,49(1):35-39
Introduction: Posterior interosseous nerve (PIN) syndrome is a rare compression neuropathy of the PIN in the region of the supinator muscle, most common by the arcade of Frohse. We aimed to specify ultrasonographic findings in patients with PIN syndrome in comparison to healthy volunteers. Methods: Ultrasound images and clinical data of 13 patients with PIN syndrome confirmed by neurological examination and electrophysiological testing were evaluated retrospectively. Anteroposterior nerve diameters measured at the arcade of Frohse were compared with those of 20 healthy volunteers. The echotexture and the presence of a caliber change of the PIN were additionally assessed. Results: Enlargement of the PIN was seen in all patients with PIN syndrome, but not in volunteers (statistically significant difference in mean diameter P < 0.05). Furthermore, edema and caliber change of the PIN were present in all patients. Conclusions: High‐resolution ultrasound allows for differentiation between patients with PIN syndrome and healthy volunteers. Muscle Nerve 49 : 35–39, 2014 相似文献