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排序方式: 共有2215条查询结果,搜索用时 31 毫秒
1.
Hommes Franziska Mohsenpour Amir Kropff Dana Pilgram Lisa Matusall Svenja von Philipsborn Peter Sell Kerstin 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2022,65(1):96-106
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Akteure der öffentlichen Gesundheit (Public Health) tragen wesentlich zu Gesundheitsschutz, -förderung und... 相似文献
2.
Martin R. Späth Malte P. Bartram Nicolàs Palacio-Escat K. Johanna R. Hoyer Cedric Debes Fatih Demir Christina B. Schroeter Amrei M. Mandel Franziska Grundmann Giuliano Ciarimboli Andreas Beyer Jayachandran N. Kizhakkedathu Susanne Brodesser Heike Göbel Jan U. Becker Thomas Benzing Bernhard Schermer Martin Höhne Markus M. Rinschen 《Kidney international》2019,95(2):333-349
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Anna C. Rienmüller Sandro M. Krieg Franziska A. Schmidt Elias L. Meyer Bernhard Meyer 《The spine journal》2019,19(1):113-120
Background Context
The concept of dynamic stabilization (DS) of the lumbar spine for treatment of degenerative instability has been introduced almost two decades ago. Dynamic stabilization follows the principle of controlling movement in the coronal plane by providing load transfer of the spinal segment without fusion and, at the same time, reducing side effects such as adjacent segment disease (ASD). So far, only little is known about revision rates after DS due to ASD and screw loosening (SL).Purpose
The present study aimed to evaluate the longitudinal revision rates following dynamic pedicle screw stabilization in the lumbar spine and to determine specific risk factors predictive for ASD, SL, and overall reoperation in a large cohort with considerable follow-up.Design
We carried out a post hoc analysis of a prospectively collected database in a level I spine center.Patients Example
The patient sample comprised 283 (151 female/132 male) consecutive patients suffering from painful degenerative lumbar segmental instability with or without spinal stenosis who underwent DS of the lumbar spine (Ulrich Cosmic, Ulrich Medical, Ulm, Germany) between January 2008 and December 2011.Outcome Measures
Longitudinal reoperation rate and risk factors predictive for revision surgery were evaluated.Methods
We analyzed the longitudinal reoperation rate due to ASD and SL and overall reoperation. Risk factors such as age, gender, body mass index, lumbar lordosis (LL), number of segments, and number of previous surgeries were taken into account. Regular and mixed model logistic regressions were performed to determine risk factors for revision surgery on a patient and on a screw level.Results
The mean age was 65.7±10.2 years (range 31–88). One hundred thirty-two patients were stabilized in 1 segment, 134 in 2 segments, 15 in 3 segments, and 2 patients in 4 segments. Reoperation rate for ASD and SL after 1 year was 7.4 %, after 2 years was 15.0%, and after a mean follow-up of 51.4±15 months was 22.6%. Reasons for revision were SL in 19 cases (6.6%), ASD in 39 cases (13.7%), SL and ASD in 6 cases, hematoma in 2 cases (0.7%), cerebrospinal fluid fistulae in 3 cases (1.1%), infection in 6 cases (2.1%), and implant failure in 1 case (0.4%). The patients' age, the number of stabilized segments, and the number of previous surgeries and postoperative LL had a significant influence on the probability for revision surgery.Conclusions
Reoperation rates after DS of the lumbar spine are comparable with rigid fixations. The younger the patient and the more segments are involved, the lower the LL and the more previous surgeries were found, the higher was the risk of revision. Risk of revision was almost twice as high in men compared with women. We therefore conclude that for clear clinical indication and careful evaluation of preoperative imaging data, DS using the Cosmic system seems to be a possible option. The presented data will help to further tailor indication and patient selection. 相似文献5.
6.
Michael Müller Lotty Rietschin Franziska Grogg Peter Streit Beat H. Ghwiler 《Hippocampus》1994,4(2):204-209
The heavy metal bismuth induces a new type of selective neuronal degeneration that shares some common aspects with that seen following hypoxia and ischemia. Continuous application of 3 μm bismuth to organotypic cultures of rat hippocampus resulted after 2–3 weeks in selective degeneration of CA1 pyramidal cells, while CA3 pyramidal cells, dentate granule cells, and subicular neurons were resistant. With 10 μm MK-801, a noncompetitive NMDA-antagonist, during the entire culturing period failed to prevent neuronal degeneration induced by 3 μm bismuth. GABA-immunoreactive interneurons were also affected by bismuth, but were generally less sensitive than CA1 pyramidal cells. Acute application of up to 100 μm bismuth did not change the electrophysiological properties of CA1 pyramidal cells. © 1994 Wiley-Liss, Inc. 相似文献
7.
New aspects of the etiology of tendon rupture 总被引:2,自引:0,他引:2
E. Knörzer W. Folkhard W. Geercken C. Boschert M. H. J. Koch B. Hilbert H. Krahl E. Mosler H. Nemetschek-Gansler T. Nemetschek 《Archives of orthopaedic and trauma surgery》1986,105(2):113-120
Summary Native collagen fibers were exposed to different dynamic loads to simulate damage to tendons and ligaments relevant clinically and for sports medicine. The results suggest that the rupture of a tendon is caused at the submicroscopic fibrillar level. Not only slow or very fast elongation, but also very fast unloading of stretched fibers seems to be responsible for disseminated damage, which reduces the stability of a fiber. This damage is induced by intrafibrillar sliding processes, which occur only a few seconds before macroscopic slippage takes place. The significance of these events for the beginning and progress of repair in vivo is discussed. The conclusions are supported by simultaneous mechanical and radiological measurements, as well as by light- and electron-microscopic results.
Zusammenfassung Zur Simulierung klinisch bzw. sportmedizinisch relevanter Schäden an Sehnen und Bändern wurden native Kollagenfasern unterschiedlichen dynamischen Belastungen ausgesetzt. Die erzielten Ergebnisse sprechen dafür, die Ursachen einer Sehnenruptur im submikroskopischen fibrillären Bereich zu suchen. Sowohl eine langsame oder ruckartige Dehnung als auch eine ruckartige Entlastung zugbelasteter Fasern scheinen für das Auftreten disseminierter, die Faserstabilität reduzierender Gefügestörungen verantwortlich zu sein. Diese Gefügestörungen werden durch intrafibrilläre Gleitvorgänge eingeleitet, die an den noch voll belastbaren Fasern nur wenige Sekunden vor dem Einsetzen eines makroskopischen Faserfließens auftreten. Die Bedeutung dieser Ereignisse für den Beginn und Verlauf einer in vivo stattfindenden Reparationsphase wird erörtert. Die Aussagen werden gestützt durch simultane mechanische und röntgenographische Messungen sowie durch makroskopische, licht- und elektronenmikroskopische Befunde.相似文献
8.
9.
Dorota Gabry's Annegret Dörfler Ala Yaromina Franziska Hessel Mechthild Krause Reinhard Oertel Prof. Dr. Michael Baumann 《Strahlentherapie und Onkologie》2008,184(1):48-53
PURPOSE: To evaluate the effect of lovastatin alone or combined with radiation on U87MG and FaDu cells in vitro and U87MG tumors in vivo. MATERIAL AND METHODS: Cell number, p21(WAF1) expression, apoptosis, reproductive cell death, and cell-cycle distribution were investigated after incubation of U87MG and FaDu cells in vitro. The effect of lovastatin (50 mg/kg/day) on tumor growth and on tumor growth delay after single-dose irradiation with 20 Gy was investigated using U87MG tumors in nude mice. RESULTS: Lovastatin dose dependently decreased cell number and proliferation of U87MG and FaDu cells. The proportion of cells in G0/G1 phase, apoptosis and p21 protein expression increased after lovastatin alone or combined with 4-Gy irradiation in both cell lines. Effects of lovastatin on cell cycle and cell number were more pronounced in U87MG compared to FaDu. No radiosensitization of clonogenic cells by lovastatin could be demonstrated in both cells lines, but the colony-forming ability after lovastatin alone was decreased in FaDu cells. In vivo, lovastatin decreased tumor volume over time but did not increase growth delay after irradiation of U87MG tumors with 20 Gy. CONCLUSION: The data support effects of lovastatin on proliferation, apoptosis and colony-forming ability in vitro and tumor volume in vivo. At the drug concentration achievable, lovastatin did not improve the effects of radiation on U87MG tumors in vivo. 相似文献
10.
Joncourt F Neuhaus B Jostarndt-Foegen K Kleinle S Steiner B Gallati S 《Human mutation》2004,23(4):385-391
Recently developed PCR systems offer online-monitoring of amplification and allow simple and reliable DNA quantification. We have used the LightCycler system to develop a simple and rapid method for direct identification of female carriers of deletions and duplications in the dystrophin gene. The challenge resides in the ability to identify the presence of a deleted or duplicated allele over the background contributed by the normal allele. Quantification is based on the determination of the ratio between potentially deleted/duplicated dystrophin exons and non-deleted/-duplicated reference exons using the unspecific dsDNA-dye SYBRgreen I. In a retrospective study, we evaluated our method in female relatives of DMD/BMD patients with known carrier status by comparative analysis of deleted or duplicated versus non-deleted/-duplicated exons. Carrier status was accurately attributed in 100% of cases, the mean ratios being 0.52+/-0.12 for deletion carriers (expected value: 0.5) and 1.56+/-0.18 for duplication carriers (expected value: 1.5) vs. 1.022+/-0.17 for non-carriers (expected value: 1.0). The method proved to be simple, rapid, reliable, and cost-effective. It may be used for direct determination of deletions/duplications in potential DMD/BMD carriers and may easily be adapted for other genetic conditions involving deletions and duplications. 相似文献