PubMed Health⌕ Search

Biomedical subjects

R Siegert

Publications and source records attributed to R Siegert.

At least 55 records · Page 3Linked to original sources
PubMed1996

Improving schizophrenic in-patients' Wisconsin card-sorting performance.

The effectiveness of a training procedure to improve schizophrenic patients' Wisconsin Card Sorting Test performance was investigated. In the absence of the monetary incentive often employed, 10 schizophrenic in-patients' performance improved with training. This study provides further evidence that the cognitive deficiency associated with the frontal lobe, implied by schizophrenic patients' typically poor Wisconsin Card-Sorting Test performance, is remediable.

Analysis of Variance↗
PubMed1996

[Ultrasound imaging of nasal bone fractures with a 20-MHz ultrasound scanner].

High frequency B-scan ultrasonography is a proven method for the assessment of skin tumors and evaluation of the thickness of skin and cartilage layers. Only limited studies have used sonography to examine bony structures. Our goal was to evaluate the importance of ultrasonography in the diagnosis of nasal fractures. Patients with clinical and/or radiological evidence for such fractures were also examined with 20 MHz B-scan ultrasonography. Results of sonography demonstrated a significant correlation with the nasal fractures present, indicating that additional radiographic examinations are unnecessary in certain cases.

Adult↗
PubMed1996

[Familial occurrence of oculoauricolovertebral dysplasia and Franceschetti syndrome].

Oculoauriculovertebral dysplasia (OAV) and the Franceschetti syndrome (FS) are well-known complexes of anomalies that have dysplasias of the external ear as a common occurrence. In this study the specific patterns of symptoms and familial occurrences of 100 patients with external ear dysplasias were examined (88 patients with OAV dysplasia and 12 patients with FS). Analyzing the pedigree data of the probands, we ascertained the relatives with striking symptoms and associated anomalies of OAV dysplasia. The aim of this study was to determine the influence of genetic transmission on OAV dysplasia in comparison to FS. A striking family history was found in 66.6% of the patients with FS. In 26.1%, family members of patients with OAV dysplasia had external ear dysplasias or other striking symptoms of OAV dysplasia. In this complex of anomalies we also found a higher frequency of skeletal deformities and congenital heart defects than in the normal population. On the basis of our results we suggest that there is a genetic transmission in patients with FS as well as in some cases with OAV dysplasia. Our findings show that it is absolutely necessary to analyze family history very carefully when discussing the recurrence risk or risk of genetic transmission.

Adolescent↗
PubMed1995

Experimental tissue expansion induces changes in expression of procollagen I and III messenger RNA.

Experimental tissue expansion was performed in nine dogs following placement of subcutaneous silicone balloons. The balloon expander was then filled with 300 ml saline immediately after implantation. Duration of expansion varied from 3 days to 124 days. Unaffected skin and skin over an empty expander served as control tissue. Dermal procollagen I and procollagen III gene expression in response to tissue expansion was investigated by dot-blot analysis using digoxigenin-labeled RNA probes complementary to either human procollagen-alpha 1(I) mRNA or procollagen-alpha 1(III) mRNA. Cross-hybridization of human probes with canine procollagen mRNA was demonstrated by Northern blot analysis. In response to the trauma of surgery, procollagen I and III mRNA transcriptions were found to be decreased significantly within the first few days after implantation. After 9 days of expansion, increased levels of procollagen I mRNA were found, while after 16 days increased levels of procollagen III mRNA were evident. The present study is the first to demonstrate changes in dermal collagen gene expression as a reaction to tissue expansion.

Animals↗
PubMed1995

[Experimental studies of chondrosynthesis for the larynx].

UNLABELLED: The aim of this study was to develop and investigate techniques for stabilising and reconstruction of defects in the larynx similar to osteosynthesis. MATERIAL AND METHODS: (1) 400 extrusion forces of sutures and various screws (Howmedica) in thyroid cartilage of fresh cadavers were measured. (2) A new screw specially designed for cartilage was developed. (3) A new technique for stabilising cartilage with a screw nut made out of bone was developed. RESULTS: The extrusion forces correlate with the calcification of the laryngeal skeleton depending on the investigated area of the thyroid cartilage and the type of suture and screws that are used, respectively. Besides the increased extrusion forces the advantages of chondrosynthesis are the possibility of axial stabilisation and of exact bridging of defects with or without implants.

Biomechanical Phenomena↗
PubMed1995

[Kikuchi lymphadenitis. A contribution to the differential diagnosis of cervical lymph node swelling of unknown origin].

According to its morphological appearance, Kikuchi's disease is also called "histiocytic necrotizing lymphadenitis". This disorder was first described in Japan in 1972 as a benign lymphadenopathy of the neck. In Germany only a few cases have been reported by pathologists, whereas most clinicians are unaware of the existence of this rare disease, which can easily be mistaken for malignant lymphoma. In 1993 three cases of Kikuchi's lymphadenitis were treated at the ENT Department of the University of Lübeck. Patients' ages ranged from 15 to 30 years old. Except for cervical adenopathy, findings in blood tests, viral serology and radiological imaging were unremarkable. While fine needle aspirations were suspicious for malignant lymphoma, a final diagnosis of self-limiting "Kikuchi's lymphadenitis" was established histologically from excised lymph nodes. In our opinion early extirpation of lymph nodes and consultation of a pathologist are necessary to make a correct diagnosis without delay. Thus, in patients with Kikuchi's lymphadenitis unnecessary staging procedures and treatment can be avoided.

Adolescent↗
PubMed1995

[The technical safety of tissue expander domes].

UNLABELLED: Since leakage of an expander dome is a well-known complication that may lead to interruption of a tissue expansion procedure, the aim of this project was to study different expansion domes in relation to a medication port after perforation with various needles. MATERIAL AND METHODS: The combinations of five different expansion domes and one medication port were tested with three different needle types having two different diameters. The force-distance curves during puncturing, the puncture forces required and the leakage opening pressures were measured after single on repeated punctures with small and large forces. A total of more than 2000 experiments were performed. RESULTS: Only one of the expander domes and the medication port had sufficient pressure stability. The technical characteristics of these devices are presented. However, the different needle types and puncture techniques had only a minor influence on the pressure stability of the expander domes.

Catheters, Indwelling↗
PubMed1994

[Pressure-volume analysis of wound suction drainage containers and suction capacity of drainage tubes].

Four low-vacuum systems and eight high-vacuum systems were examined with special reference to the pressure-volume relations. The maximum filling volume for adequate transport of wound secretion was determined for each type. The use of a synthetic wound fluid instead of water resulted in a smaller aspiration volume. Enlargement of the tube diameter resulted in a reduced initial vacuum for the low-vacuum systems, whereas the high-vacuum systems were not affected. Normal drain tubes were compared with "Ulm drains" and silicon tubes for suction capacity. The suction maximum of normal tubes and silicon tubes was located at the proximal holes of the perforated tubes. The "Ulm drain," with perforation diameter increasing continuously to the distal end of the tube, was found to exert suction even at the more distal part of the tube. It is estimated that this tube allows locally more balanced vacuum in the wound.

Animals↗
PubMed1994

[Epidermal proliferation rate after skin expansion in the dog model].

The aim of this study was to evaluate the time course of the epidermal proliferation under the influence of skin expansion. Therefore 99 expanders were implanted in 18 beagles. The expansion times were between 2 hours and 4 months. Cells in the S-phase were marked by in vivo application of bromodesoxyuridine (BrdU). The tissue specimens were immunohistochemically stained and positive nuclei counted. The proliferation index increased markedly about 32 hours after the onset of the expansion and decreased afterwards slowly during the first week. Because the dog is the most appropriate species for experimental expansion studies (4,5) it can be assumed that skin expansion leads to a stimulation of the epidermal proliferation during the first few days also under clinical conditions. Nevertheless, the amount of skin that can be surgically used depends not only on the characteristics of the epidermal layer, but also on the dermis with its strong fibre system. Own studies published elsewhere (8) have shown that the dermal fibres react much slower to the expansion stimulus, so that even though there is an early epidermal proliferation increase new surgically applicable skin can only be produced by long-term expansion.

Animals↗
PubMed1994

[Complications of otoplasty and their treatment].

The multitude of otoplastic techniques, described in literature, which are based, as the case may be, on one of the three standard techniques for the correction of prominent ears, shows there is no single technique for satisfactory results. Hence, early and late complications can occur after otoplasty, both immediately and up to 2 weeks and later. These complications include granulomas, allergic reactions, keloids, reprotrusion as well as severe deformities with different defects, besides disturbances of sensitivity, often requiring repeat surgery. The management and treatment of the various complications are described and some reconstruction procedures are demonstrated, employing fascia, skin and cartilage to keep the damage at a minimum.

Adolescent↗
PubMed1994

[Tissue expansion. Part 1: Technical and physiologic principles].

The technique of tissue expansion can now be used to prepare skin for reconstructive operations. This method has been propagated during the last 15 years, but its use has varied from great enthusiasm with exaggerated expectations to disillusion due to high complication rates. For an efficient and successful application of skin expansion an understanding of skin reactions and their control is mandatory. In this review, the biological principles of expansion, various expansion protocols and their objectives, control during the filling phase and preventive measures to avoid complications are described. For clinical use it is important that there is not one but three distinct types of expansion: an intraoperative, intermittent expansion for gentle subcutaneous skin mobilization, a short time period for expansion (between 1-2 weeks) to increase the dermal microcirculation and the "classic" prolonged period of expansion to create new skin for the reconstruction required.

Cell Division↗
PubMed1993

Adults' conceptions of everyday memory failures in others: factors that mediate the effects of target age.

This study investigated young and older adults' conceptions of memory failure in others. One hundred young and 100 older adults rated memory failures in targets of 20, 40, 60, and 80 years of age as to how likely the memory failures were due to lack of effort or lack of ability. With increasing age, targets' forgetful episodes were rated as less likely to be caused by lack of effort and more likely to be due to lack of ability. A Subject Age x Target Age interaction on ability ratings showed age to be more salient for older subjects. Memory content, type of memory, subject sex, and target sex all influenced judgment of memory failure. The results support Erber's (1989) notion of a double standard in memory-failure appraisal; they demonstrated that adults' conceptions of memory include a decremental view of memorial ability with increasing age that is differentially sensitive to subject, target, and memorial variables.

Adult↗
PubMed1993

Clinical and experimental evaluation of intermittent intraoperative short-term expansion.

To assist in the closure of defects in the region of the head lack and neck, a number of surgeons recommend intermittent intraoperative short-term expansion to exploit the biomechanical properties of the skin. It was the aim of this study to assess quantitatively the amount of intraoperative "tissue gain," to analyze its origin, and to throw light on its underlying biomechanical processes. A total of 285 expansions in 5-minute intervals under a constant tissue pressure of 100 mmHg were performed on 30 patients with severe microtia. The volumes achieved were protocolled, and microcirculation was monitored with the help of a laser-Doppler flowmeter. Expanders exerting a tissue pressure of 100 mmHg for more than 80 cycles lasting 20 minutes also were employed in five dogs. Apart from determining the volumes, changes in distance between the skin tattoos and the diameter of the expander base were recorded. A volume increase of about 10 percent per hour was recorded for the human patients and an increase of about 30 percent per hour for the animals. After reaching a maximal increase in length of 15 to 20 percent, there was no further skin elongation despite increasing volumes. Instead, the expander began to move into the subcutaneous tissue so that its diameter showed a continuous increase. We can conclude on the basis of these results that the increase in volume during intermittent intraoperative short-term expansion is not caused by the proclaimed "creep" behavior of the skin.

Animals↗
PubMed1993

Psychiatric disorder and disability in New Zealand long-stay psychiatric patients.

A study was undertaken of the prevalence of physical disease, psychiatric disorder and deviant behaviour in a sample of 137 long stay psychiatric patients at Porirua Hospital near Wellington, New Zealand. Patients were in the main male, single, middle-aged to elderly and of European descent. Schizophrenia was the most common diagnosis. Psychiatric symptoms were moderately severe, the most common being unusual mannerisms and posturing, anxiety, blunted affect, tension, unusual thought content and somatic concerns. Known physical disorders were present in 66 patients. Levels of neuroleptic medication were high and tardive dyskinesia was observed in almost 60% of patients. Frequency of deviant behaviour was low in absolute terms but nonetheless problematic. The frequency of deviant behaviour was similar to those reported for British patients.

Activities of Daily Living↗
PubMed1993

[Pressure-volume analysis of wound suction drainage systems and their importance in otorhinolaryngologic surgery].

Four low-vacuum systems and 6 high-vacuum systems were examined concerning their pressure-volume relationships. For each type the maximum filling volume for sufficient drainage of wound secretions was determined. The use of a wound fluid substitute instead of water resulted in a lower aspiration volume. Enlargement of the tube diameter showed a reduction in the initial vacuum for the low-vacuum systems, whereas the high-vacuum systems were not affected. The amounts of postoperative wound fluid lost in selected ENT operations were determined. Considering the volume capacity of the wound drainage systems, the type of container can be chosen that eliminates the necessity for later bottle exchange on the wards, thus avoiding a potential risk for wound infection. The high-vacuum systems with a volume capacity of 150 or 200 ml are sufficient for parotidectomies, costal cartilage resections and reconstructions of the auricle, resulting in good postoperative wound adaptation and also preventing the need for postoperative bottle exchanges.

Animals↗