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排序方式: 共有1072条查询结果,搜索用时 484 毫秒
51.
52.
Felix S. Seibert Julia Steltzer Eduardo Melilli Gerrit Grannas Nikolaos Pagonas Frederic Bauer Walter Zidek Josep Grinyó Timm H. Westhoff 《Clinical transplantation》2014,28(9):1004-1009
Calcineurin inhibitors (CNI) are potent vasoconstrictors and induce an acceleration of arteriosclerosis, thus contributing to the cardiovascular risk after renal transplantation. The study compares the impact of belatacept and cyclosporine A (CsA) on arterial stiffness and central aortic blood pressure. We performed a case–control study in 46 patients (23 on belatacept and 23 on CsA) matched for age, body mass index, time after transplantation, and time on dialysis prior to transplantation. Pulse wave analysis (SphygmoCor, AtCor®) was used to assess central aortic blood pressure, aortic augmentation pressure, and pulse wave velocity (PWV) as a marker of arterial stiffness. Assessment of vascular function was performed after a minimum of 20 months and a median follow‐up of 81 months post‐transplant. Peripheral systolic and diastolic blood pressure did not significantly differ in the two groups (p > 0.05 each). The central aortic augmentation pressure was higher in the CsA group (12.7 mmHg vs. 7.3 mmHg, p = 0.048). PWV as a measure of arterial stiffness did not differ in the two groups. Thus, belatacept is not associated with a significant difference in arterial stiffness compared to CsA after a median of 81 months post‐transplant. It is associated, however, with a lower aortic augmentation pressure, a strong independent cardiovascular risk factor. 相似文献
53.
Tolga Taha Sönmez Andreas Prescher Anastasios Kanatas Arash Zaker Shahrak Marcus Gerressen Matthias Knobe Selman Hakki Altuntas Ali Modabber Timm Walter Steiner Ralf Smeets Alireza Ghassemi Frank Hölzle 《The British journal of oral & maxillofacial surgery》2014
The scapula free flap is often the first choice for reconstruction of bony defects of the facial skeleton. However, the vascularised rib as part of a free rib osteomyocutaneous flap may be a suitable second choice. We have investigated the morphology and clinical dimensions of the 7th rib and the scapula, and the ability of the available bone to carry dental implants. The age and sex of the cadaver, and the donor side, were also recorded. The dimensions of the scapulas and 7th ribs (n = 130 of each) from 65 cadavers were measured at 4 different points using osteometric methods. Examination showed that bone from the scapula and 7th rib were sufficient for placement of implants. The 7th rib gave reliable measurements for both height and width, and a consistent relation between compact and cancellous bone. Although the scapula provided adequate compact and cancellous bone, there were variations depending on the segment of bone chosen. Bones from male cadavers were more suitable for implantation. In both the scapula and the 7th rib ageing had a significant adverse effect in only one dimension. Most points of measurement have satisfactory bony dimensions for insertion of dental implants. 相似文献
54.
Susanne Trainotti Stefan Raith Marco Kesting Stefan Eichhorn Florian Bauer Andreas Kolk Bernd Lethaus Frank Hölzle Timm Steiner 《Clinical oral investigations》2014,18(4):1291-1298
Objectives
The main goal of the present study was to compare the biomechanical stability of locking plates and conventional miniplate combinations in human mandibles reconstructed with fibular grafts.Materials and methods
A specially developed and well-proven testing device reproduced the in vivo loading conditions on the mandible. Cadaveric human mandibles (n?=?12) reconstructed with harvested human fibular bone grafts were divided into two groups, and different osteosynthesis systems were applied using two lines of plates per osteotomy. On the test apparatus, the specimens were stressed to failure, and interfragmentary movement was monitored and quantified with a contact-free optical measurement system.Results
The relevant interfragmentary movement results from a Euclidean summary calculation which considered all three spatial angles around the axes. Using values up to a maximum load of 300 N, the conventional six-hole miniplates (profile 1.0) had an average value of 7.45°?±?1.46°, and the locking six-hole plates (profile 1.3) had an average value of 12.16°?±?2.37° for rotational interfragmentary movement. The miniplate system exhibited a significantly superior performance in fixation compared to the fixed-angle system (p?<?0.05).Conclusion
According to these biomechanical experiments, both osteosynthesis devices provided sufficient stabilization at loads of up to 300 N. The six-hole miniplate system provided better stabilization of the osteotomy gap for mandibles reconstructed with fibular grafts.Clinical relevance
The osteosynthesis system is essential for primary stability and the avoidance of pseudarthrosis formation. This study demonstrates that the miniplates provide sufficient stabilization and offers a method to improve fixation in reconstructed mandibles. 相似文献55.
Yingchun Zhang Andrew D. Bicek Guangjian Wang Gerald W. Timm 《International urogynecology journal》2010,21(10):1279-1284
Introduction and hypothesis
This study aims to test the hypothesis that a urethra-to-bladder inhibitory pathway exists through which periurethral neuromuscular electrical stimulation (NMES) inhibits overactive bladder contractions in rats. 相似文献56.
57.
Fructooligosaccharides exhibit more rapid fermentation than long-chain inulin in an in vitro fermentation system 总被引:1,自引:0,他引:1
This study investigated how chain length affects fermentation properties of fructooligosaccharides (FOSs) and inulin (IN). Chain lengths of FOSs and IN vary from an average degree of polymerization (DP) of 3 to greater than 20. Three samples classified as FOSs (samples A, B, and C) and 3 samples classified as IN (samples D, E, and F) were fermented via an in vitro batch method with human fecal inoculum as the source of microbes. Samples were removed at 0, 4, 8, 12, and 24 hours for total short-chain fatty acid (SCFA), acetate, propionate, and butyrate measurement via gas chromatography. Sample chain length did not affect SCFA concentrations in a predictable manner. Sample E (90%-94% DP > 10, 6%-10% DP = 1-2), a mixture of long-chain IN and short-chain FOS, produced significantly more total SCFA and acetate than the other samples. Sample F (DP > 20), the longest-chain IN, produced the lowest concentration of butyrate at 24 hours. The rate of FOS fermentation was higher than IN fermentation during 0 to 4 hours for all SCFAs, and the rate of IN fermentation was higher than FOS fermentation during 12 to 24 hours for all SCFAs. Chain length affects in vitro fermentability, with short chains being rapidly fermented and long chains being steadily fermented. Clinical studies should follow this work to verify if these differences exist in vivo. 相似文献
58.
Schittkowski M Stropahl G Timm A Guthoff R 《Klinische Monatsbl?tter für Augenheilkunde》2002,219(8):602-608
BACKGROUND: The purpose of this report is to describe the clinical characteristics, management and histological findings in a patient with obstruction of the nasolacrimal duct caused by a cylindroma. About 618 lacrimal sac tumours have been reported previously in reviews and case reports, which were reviewed after searching in medline database. CASE REPORT: A 79-year old man suffered from multiple cylindromas (Spiegler tumour) on his head for about 40 years. He presented with a 6 months' history of left-sided epiphora and a painless medial canthal mass of various size. A tumour which caused nasolacrimal duct obstruction was found during dacryocystorhinostomy. After complete excision histological examination revealed a cylindroma, which had shown expansive growth from dermis to the lacrimal sac area. The patient felt well; there was no longer any epiphora or dacryocystitis after the operation. CONCLUSION: Although very rare, lacrimal sac tumours must be considered in the differential diagnosis of nasolacrimal duct obstruction. To our knowledge this case represents the first report on an atypical manifestation on a Spiegler tumour in the lacrimal sac region. 相似文献
59.
Two novel antifungal agents belonging to the sordarin family have been isolated from fermentations of Sordaria araneosa by bioassay-guided purification and their structures elucidated by NMR techniques. Neosordarin (1) is closely related to the recently discovered hypoxysordarin (2), with only small differences on the aliphatic side chain acylating the hydroxyl in the 3'-position of the sordarose moiety. Hydroxysordarin (3) closely resembles sordarin (4), the only slight difference being the replacement of sordarose with altrose as the sugar unit. 相似文献
60.