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排序方式: 共有3283条查询结果,搜索用时 15 毫秒
1.
David Simon Koray Tascilar Sara Unbehend Sara Bayat Andreas Berlin Anna-Maria Liphardt Timo Meinderink Juergen Rech Axel J Hueber Georg Schett Arnd Kleyer 《Journal of bone and mineral research》2020,35(9):1695-1702
The impact of primary hand osteoarthritis (HOA) on bone mass, microstructure, and biomechanics in the affected skeletal regions is largely unknown. HOA patients and healthy controls (HCs) underwent high-resolution peripheral quantitative computed tomography (HR-pQCT). We measured total, trabecular, and cortical volumetric bone mineral densities (vBMDs), microstructural attributes, and performed micro–finite element analysis for bone strength. Failure load and scaled multivariate outcome matrices from distal radius and second metacarpal (MCP2) head measurements were analyzed using multiple linear regression adjusting for age, sex, and functional status and reported as adjusted Z-score differences for total and direct effects. A total of 105 subjects were included (76 HC: 46 women, 30 men; 29 HOA: 23 women, six men). After adjustment, HOA was associated with significant changes in the multivariate outcome matrix from the MCP2 head (p < .001) (explained by an increase in cortical vBMD (Δz = 1.07, p = .02) and reduction in the trabecular vBMD (Δz = −0.07, p = .09). Distal radius analysis did not show an overall effect of HOA; however, there was a gender-study group interaction (p = .044) explained by reduced trabecular vBMD in males (Δz = −1.23, p = .02). HOA was associated with lower failure load (−514 N; 95%CI, −1018 to −9; p = 0.05) apparent in males after adjustment for functional status. HOA is associated with reduced trabecular and increased cortical vBMD in the MCP2 head and a reduction in radial trabecular vBMD and bone strength in males. Further investigations of gender-specific changes of bone architecture in HOA are warranted. © 2020 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research. 相似文献
2.
The recently developed ELISA for the thrombin-antithrombin III complex (TAT) is a sensitive, specific, and simplified means of detecting intravascular coagulation. For further evaluation of the thrombogenicity of a polyamide (P) and a Hemophan (H) hollow-fibre dialyzer a cross-over study was done in ten stable patients on maintenance hemodialysis. At the same doses of heparin (mean bolus of 30 U/kg bw and maintenance doses of 86 U/kg bw), thrombin time and partial thromboplastin time were significantly lower using H. At the end of dialysis TAT was significantly higher in H (mean +/- SEM before HD 3.57 +/- .56, at 240 min 14.9 +/- 6.5 ng/ml, p less than 0.05, Wilcoxon-test) than in P (before HD 4.36 +/- .98, at 240 min 8.95 +/- 3.0 ng/ml, p less than 0.05 H 240 vs. P 240, Wilcoxon-test). Visible clotting was more pronounced in the H filter. Among other favourable features of blood compatibility the polyamide/polyvinylpyrrolidone copolymer with a hydrophilic/hydrophobic microdomain structure has less thrombogenicity. The modified cellulosic membrane H has advantages in complement activation and leukocyte depression, but thrombogenicity seems less favourable since the incorporated diethyl-amino-ethyl groups with their positive charge bind and inactivate negatively charged heparin. 相似文献
3.
C. Hueter Ledderhose R. Schultze 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1882,17(5-6):577-582
Ohne Zusammenfassung 相似文献
4.
To overcome specific absorption rate (SAR) limitations of spin-echo-based MR imaging techniques, especially at (ultra) high fields, rapid acquisition relaxation enhancement/TSE (turbo spin echo)/fast spin echo sequences in combination with constant or variable low flip angles such as hyperechoes and TRAPS (hyperTSE) have been introduced. Due to the multiple spin echo and stimulated echo pathways involved in the signal formation, the contrast behavior of such sequences depends on both T2 and T1 relaxation times. In this work, constant and various variable flip angle sequences were analyzed in a volunteer study. It is demonstrated that a single effective echo time parameter TE(eff) can be calculated that accurately describes the overall T2 weighted image contrast. TE(eff) can be determined by means of the extended phase graph concept and is practically independent of field strength. Using the described formalism, the contrast of any TSE sequence can be predicted. HyperTSE sequences are demonstrated to show a robust and well-defined T2 contrast allowing clinical routine MRI to be performed with SAR reductions of typically at least 70%. 相似文献
5.
Axel Olsen T. Antoine Frommolt Theo Pütz Rudolf Koch Hans Heidler Kurt Walther Schultze H. A. Schmitz Elisabeth Koch Möhlmann Diethelm W. Janisch-Raschkowitsch Hansen Ostertag H. Dietel 《International journal of legal medicine》1943,37(3-4):197-206
Ohne Zusammenfassung 相似文献
6.
Matthias Guckenberger MD Juergen Meyer Juergen Wilbert Kurt Baier Otto Sauer Michael Flentje 《Strahlentherapie und Onkologie》2007,183(6):307-313
PURPOSE: To evaluate the precision of image-guided radiotherapy (IGRT) using cone-beam computed tomography (CB-CT) for volume imaging and a robotic couch for correcting setup errors in six degrees of freedom. PATIENTS AND METHODS: 47 consecutive patients with 372 fractions were classified according to whether a patient fixation device was used (pat(fix): n = 28) or not (pat(non-fix): n = 19). Prior to treatment a CB-CT was acquired and translational and rotational setup errors were corrected online without an action level using a robotic couch (HexaPOD). A second CB-CT was acquired after the correction process and after treatment in 134 and 238 fractions, respectively. RESULTS: In 17 fractions (4.6%) rotational errors > 3 degrees exceeded the motion range of the HexaPOD. Errors (3D vector) after the correction process were significantly smaller for pat(fix) compared to pat(non-fix) (p < 0.001): 0.9 mm +/- 0.5 mm and 1.6 mm +/- 0.8 mm, respectively. For pat(non-fix) the correction of rotational errors resulted in displacements of the patients on the angled couch of 0.6 mm/1 degree. Intrafractional motion further decreased precision in pat(non-fix) but not in pat(fix). CONCLUSION: Very high precision in cranial and extracranial treatment of immobilized patients was demonstrated. Without application of adequate immobilization the correction of rotational errors and intrafractional patient motion significantly decreased the accuracy of the online correction protocol. 相似文献
7.
Summary Ten mumps virus isolates recovered during an epidemic in Switzerland between Autumn 1992 and Spring 1993 were compared by nucleotide sequence analysis of the SH gene. The isolates were found to belong to two distinct yet closely related wild type strains in a newly identified European mumps virus lineage. 相似文献
8.
To support blood supply in the growing field of cancer surgery and to avoid transfusion induced immunomodulation caused by the allogeneic barrier and by blood storage leasions we use intraoperative blood salvage with blood irradiation. This method is safe as it provides efficient elimination of contaminating cancer cells, and as it does not compromise the quality of RBC. According to our experience with more than 700 procedures the combination of blood salvage with blood irradiation also is very effective in saving blood resources. With this autologous, fresh, washed RBC a blood product of excellent quality is available for optimal hemotherapy in cancer patients. 相似文献
9.
Prof. Friedrich Schultze 《Journal of neurology》1920,65(1-2):1-25
Ohne ZusammenfassungHerr Dr. Sioli konnte auch bei erneuter Untersuchung mit Spirochätenfärbung und Bielschowsky-Färbung keinen andern Befund als früher erheben. Die Zahl der Achsenzylinder in den Herden ist nur in geringem Maße verringert. 相似文献
10.