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排序方式: 共有399条查询结果,搜索用时 15 毫秒
1.
Although symptom validity tests have become available to German test users during the last few years, there is very little research into measures of negative response bias in personality assessment. The present study investigates the effects of negative response bias as measured by the Word Memory Test (WMT) and the Structured Inventory of Malingered Symptomatology (SIMS) on self-report personality scales. A retrospective analysis was performed on data from 93 patients who had undergone neuropsychiatric assessment in the context of independent medical examination. Complete data sets were available for the WMT, the SIMS, and the Freiburg Personality Inventory-Revised (FPI-R). Significant differences were found for a number of personality scales, depending on WMT and SIMS classification. The FPI-R validity scale (Openness) was linked to neither WMT nor SIMS, whereas the results in the latter two instruments showed a significant overlap of classification results (φ=0.44). A principal axis analysis yielded corresponding results. It is concluded that self-report personality measures may be considerably distorted by negative response bias. FPI-R Openness scale scores do not allow any interpretation in terms of negative response bias. More effort should be directed in German-speaking countries towards the development and validation of appropriate validity scales. 相似文献
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3.
Tissue engineering of bone for mandibular augmentation in immunocompetent minipigs: preliminary study. 总被引:4,自引:0,他引:4
Andreas Gr?ger Svea Kl?ring Hans-Albert Merten J?rg Holste Christian Kaps Michael Sittinger 《Nordisk plastikkirurgisk forening [and] Nordisk klubb for handkirurgi》2003,37(3):129-133
Large mandibular defects caused by trauma, infection or resection of a tumour are still a major problem for plastic and maxillofacial surgeons. The modern concept of tissue engineering combines the osteoinductive effects of osteogenic cells with a suitable scaffold structure to promote differentiation of osteoblasts and optimal matrix production. Critical size mandibular bone defects were therefore made to investigate the osteogenic potential of periosteal cells and a bioabsorbable polymer fleece (Ethisorb 510) in minipigs. Periosteal cells were isolated from four minipigs, expanded in vitro and seeded with fibrin glue into Ethisorb 510 fleeces. Tissue constructs were used to repair critical size mandibular defects and compared with two minipigs with untreated bone defects. Bone healing was evaluated after 90 and 180 days by radiographs and a histological scoring system. The radiographs showed increased radiodensity of defects filled with the cell-fibrin-fleece-constructs compared with the untreated control group after 90 and 180 days in vivo. The defects repaired by the cell-fibrin-scaffolds (180 days in vivo) obtained the highest histological mean score 2.9 (range 2-3), while defects filled by cell-fibrin-scaffolds (90 days in vivo) achieved a mean score of 2.1 (range 2-3). In contrast, the control group (n = 2) scored 1 and 2. The results show that a combination of periosteal cells and polymer fleeces may be a promising approach for clinical mandibular augmentation. 相似文献
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5.
Dr. Hans-Albert Schumacher Christoph Bourauel Dieter Drescher 《Journal of orofacial orthopedics》1998,59(3):139-149
In orthodontic treatment employing arch guided tooth movement, rectangular wires are usually used to achieve three-dimensional controlled tooth movement. In the intention to optimize sliding mechanics and to improve the comfort of patients, edge beveled rectangular orthodontic wires are offered by different manufacturers. The objective of the study presented was to investigate the influence of differing but defined wire roundings on sliding mechanics of canine retraction. Employing the 0.018″ slot system, 0.016″×0.022″ standard steel wires (Remaloy and Remanium, Dentaurum Comp.) were tested. Force loss due to friction during canine retraction was determined using the Orthodontic Measurement and Simulation System (OMSS). In the arch guided distalization of canines, the average loss of force caused by friction was determined to be approximately 50%. Comparing wires with different edge bevel, the rounded wire in contrast to the wire with sharpest edge configuration results in a reduction of friction. Even a moderate wire rounding of the 0.016″×0.022″ steel wire results in about 10% reduction in frictional losses. However, dynamic analysis of tooth movement with the OMSS shows that there is no further improvement of sliding mechanics using wires with edge bevel exceeding the standard rounding of rectangular wires. In contrast, a strong edge bevel may result in a considerable loss of leveling. 相似文献
6.
J. Kreuzer S. Denger A. Schmidts L. Jahn M. Merten E. von Hodenberg 《Journal of molecular medicine (Berlin, Germany)》1996,74(3):161-165
The accumulation of blood monocytes at sites of predilection of the vessel wall is an early cellular event of atherogenesis. Proteins of the vessel wall may facilitate monocyte adhesion and thus promote their recruitment. It has been shown that the relative content of extracellular fibrinogen increases during lesion development, and this study investigated the contribution of immobilized fibrinogen to monocyte adhesion and the underlying mechanism. Freshly isolated human blood monocytes were cultivated in serum-free RPMI 1640 in tissue culture wells precoated with albumin, fibrinogen, or fibrin. After 16 h the plates were washed and adherent cells enumcrated. Immobilized fibrinogen enhanced monocyte adhesion more than 1.9-fold compared to immobilized albumin or fibrin (P<0.05). Concomitant addition of the protein kinase C (PKC) inhibitors staurosporine or H7 suppressed monocyte adherence to immobilized fibrinogen but exerted no significant effect upon adhesion to any other surface tested. Stimulation of monocytes using phorbol myristate acetate resulted in increased binding of monocytes on fibrinogen but not on bovine serum albumin. When PKC activity was reduced through prolonged incubation with PMA for 16h, a significant reduction of monocyte adhesion on fibrinogen was observed. Peptides containing RGD sequences, which have been demonstrated to be ligands for certain integrins, did not inhibit monocyte adhesion. The data suggest that fibrinogen promotes monocyte adhesion in vitro by a PKC-dependent mechanism. PKC appears to be important not only for the initial cell adhesion but also for sustained binding of monocytes to fibrinogen.Abbreviations
BSA
Bovine serum albumin
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ECM
Extracellular matrix
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PKC
Protein kinase C
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PMA
Phorbol myristate acetate 相似文献
7.
Symptom validity testing is a major topic in the field of neuropsychological research, but until now, few studies focus on effort testing in children. Three symptom validity tests (SVTs), the Medical Symptom Validity Test, the Test of Memory Malingering, and the Fifteen Item Test plus several standard neuropsychological tests were administered to 73 German-language school children from 6 to 11 years.Participants were either instructed to give full effort or to follow a malingering scenario. It could be demonstrated that, except for one child, all participants with a basic reading level of grade 2 were able to pass all administered SVTs according to established cutoffs for poor effort (i.e., earned a score higher than the cutoff). For the experimental malingerers, however, it was fairly difficult to act according to the scenario throughout the session. While they scored worse in the neuropsychological tests, all but one of them failed at least one SVT. The results support the use of SVTs in childhood age. More elaborate experimental designs and studies with bona-fide patients and suspected malingerers are needed in order to evaluate both the appropriateness of available effort tests and the capabilities of children to fake poor performance. 相似文献
8.
Thomas Merten Paul Green Matthias Henry Nina Blaskewitz Robbi Brockhaus 《Archives of clinical neuropsychology》2005,20(6):719-726
Although symptom validity testing is an integral part of the repertory of neuropsychologists in a number of countries, this is not yet true for Germany. The German adaptations of two effort tests, the Medical Symptom Validity Test (MSVT) by Green and the Amsterdam Short-Term Memory Test (ASTM) by Schmand et al., were investigated with a German-language sample. An analog study was performed with 18 healthy experimental malingerers and 18 controls with a mean age of 25.4 years. The scenario contained detailed information about mild post-traumatic cognitive impairment, as well as an explicit warning against symptom exaggeration. In addition to MSVT and ASTM, the Trail Making Test (TMT), the Complex Figure Test (CFT), and Digit Span were performed. Half of the sample were also given Rey's 15-Item-Test (FIT). Both groups were significantly different in all effort and performance measures, with the exception of the ratio TMT-B:TMT-A. With MSVT and ASTM, correct classification of group membership was between 97 and 100%. For the ratio TMT-B:TMT-A, there was a considerable overlap in the test scores for the two groups and the sensitivity of the FIT was too low. Although the ASTM and the MSVT were identified by a number of subjects as possible effort measures, both tests obtained very good results within this analog design. 相似文献
9.
In recent years, lengthening the human mandible by distraction osteogenesis has become an accepted treatment to correct severe mandibular hypoplasia. Using intraoral unidirectional and extraoral bidirectional distraction devices we report about our experiences and results in the application of the bone distraction technique in four selected cases of syndromal disease, including various forms of mandibular hypoplastic malformations. The patients involved were a boy with Pierre Robin syndrome, a girl with unilateral facial hypoplasia in Goldenhar's syndrome, a case with Nager's syndrome, and a rare case of midline deficiency caused by partial deletion of chromosome 18 (18p-syndrome). The distraction period lasted from 6 to 30 days and new bone formation, ranging from 6 to 28 mm, was achieved. 相似文献
10.
An item analysis of the Hooper Visual Organization Test (VOT) was performed using the test protocols of 320 German-speaking neurological patients with a mean age of 51.3 years. All patients presented some form of cerebral pathology. The sample yielded a mean test score of 18.8 (SD = 6.2). Estimates of internal consistency of the total scale yielded acceptable results (>.88). Although the VOT was judged to be a useful instrument for assessing visuoperceptual and visuospatial-organizational dysfunction, item characteristics of the test are not satisfactory. In particular, the item ranking does not correspond to the order of difficulty. Moreover, in their current form, scoring rules of a number of items seem to be arbitrary and not founded on empirical data. A revision of the VOT is proposed to improve its psychometric properties. 相似文献