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1.
Max Heiland Philipp Pohlenz Marco Blessmann Christian R Habermann Lars Oesterhelweg Philipp C Begemann Christian Schmidgunst Felix A S Blake Klaus Püschel Rainer Schmelzle Dirk Schulze 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(6):814-820
OBJECTIVE: The aim of this study was to evaluate soft tissue image quality of a mobile cone-beam computed tomography (CBCT) scanner with an integrated flat-panel detector. STUDY DESIGN: Eight fresh human cadavers were used in this study. For evaluation of soft tissue visualization, CBCT data sets and corresponding computed tomography (CT) and magnetic resonance imaging (MRI) data sets were acquired. Evaluation was performed with the help of 10 defined cervical anatomical structures. RESULTS: The statistical analysis of the scoring results of 3 examiners revealed the CBCT images to be of inferior quality regarding the visualization of most of the predefined structures. Visualization without a significant difference was found regarding the demarcation of the vertebral bodies and the pyramidal cartilages, the arteriosclerosis of the carotids (compared with CT), and the laryngeal skeleton (compared with MRI). Regarding arteriosclerosis of the carotids compared with MRI, CBCT proved to be superior. CONCLUSIONS: The integration of a flat-panel detector improves soft tissue visualization using a mobile CBCT scanner. 相似文献
2.
Deborah Bray Preston Anthony R D'Augelli Cathy D Kassab Richard E Cain Frederick W Schulze Michael T Starks 《AIDS education and prevention》2004,16(4):291-303
Research investigating predictors of risky sexual behavior of rural MSM is sparse, even though the prevalence of HIV in rural areas has increased. This study explored two sets of predictors of 93 rural MSM's levels of risky sexual behavior: mental health variables and stigma emanating from men's family members, health care professionals, and people in the rural communities in which they live. Over 47% of the men were found to be at modified high to high risk. Logistic regression using a continuation logit model was used to test the relationship of the predictor variables and the four levels of risk. Findings indicate that self-esteem was predictive of the highest sexual risk behavior but not lower levels of risk. Stigma was predictive of modified high sexual risk when compared to low and no risk categories. No variables differentiated men at low risk from men at no risk. 相似文献
3.
Thomas Teltzrow Franz-Josef Kramer Andrea Schulze Carola Baethge Peter Brachvogel 《Journal of cranio-maxillo-facial surgery》2005,33(5):307-313
INTRODUCTION: The aim of this study was to review complications in a series of 1264 consecutive patients who were operated in a single centre during a 20-year-period. MATERIAL AND METHODS: Complications were documented, their incidences calculated and compared with data from the literature. RESULTS: In 35 patients (2.8%) infection developed requiring extraoral incision and drainage; in 27 patients (2.1%) the inferior alveolar nerve was inadvertently cut; 18 patients (1.4%) had to undergo re-operation due to bending or fracture of osteosynthesis material; 15 patients (1.2%) suffered from bleeding complications; in 12 patients (0.9%) an unfavourable split occurred. In 8 patients (0.6%) foreign bodies were left in situ; in 7 patients a partial weakness of the facial nerve occurred, which was permanent in 1 patient. Six patients (0.5%) with a significantly higher age than average (mean: 33.6 years in comparison with 23.1 years) developed non-union at the site of osteotomy, and the mandible had to be bone grafted. Two patients (0.2%) developed osteomyelitis, and in one patient airway problems led to a need for tracheostomy (0.1%). CONCLUSION: Although some of these complications of bilateral sagittal split with osteotomy carry severe limitations in health related quality of life, it remains an overall safe procedure, demanding, however, comprehensive informed consent. Good knowledge of technical reasons for these complications should help to reduce their incidence. 相似文献
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Paul Christian Schulze 《European heart journal》2007,28(9):1052-1053
Chronic heart failure is defined as the inability of the heartto meet the circulatory demands of the organism. While cardiacinjury, e.g. of ischaemic, toxic, metabolic, or genetic cause,is the initial abnormality, secondary changes occur over thecourse of the disease affecting most organ systems. This leadsto a variety of pathologic changes including endothelial, pulmonary,hepatic, renal, endocrine and skeletal muscle abnormalities,and the state of multi-organ impairment in chronic heart failureis now considered the syndrome of chronic heart failure.1 A neuroendocrine activation has been described early in 相似文献
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K Müssig S Kaltenbach C Maser-Gluth M F Hartmann S A Wudy M Horger B Gallwitz F Raue H-U H?ring E Schulze 《Experimental and clinical endocrinology & diabetes》2006,114(4):208-214
Congenital adrenal hyperplasia results from 21-hydroxylase deficiency in more than ninety percent of cases. The classical form of 21-hydroxylase deficiency presents in the neonatal period with virilization or adrenal insufficiency, with or without concurrent salt wasting. We report on a rare case of classic 21-hydroxylase deficiency diagnosed in late adulthood. A 39-year-old male patient presented for workup of infertility. Urologic investigation revealed small testes, bilateral testicular masses, and asthenozoospermia. The patient's steroid metabolism showed markedly increased levels of adrenal androgens, in particular of 17-hydroxyprogesterone amd 21-deoxycortisol. The gas chromatographic-mass spectrometric (GC-MS) urinary steroid profile was dominated by metabolites of 17-hydroxyprogesterone, while the endogenous glucocorticoid production was subnormally low. ACTH levels in plasma were elevated. These hormonal findings were consistent with 21-hydroxylase deficiency. Therapy with dexamethasone was initiated. The CTP21A2 gene analysis revealed the mutation I172N (ATC --> AAC) in exon 4 of allele 1 and a large gene deletion in allele 2. Cases of 21-hydroxylase deficiency diagnosed in late adulthood are rare; however, clinicians should be alert of this possibility. 相似文献
8.
Cell culture-based influenza vaccine manufacturing is of growing importance. Depending on virus strains, differences in infection dynamics, virus-induced apoptosis, cell lysis and virus yields are observed. Comparatively little is known concerning details of virus–host cell interaction on a cellular level and virus spreading in a population of cells in bioreactors. In this study, the infection of MDCK cells with different influenza A virus strains in lab-scale microcarrier culture was investigated by flow cytometry. Together with the infection status of cells, virus-induced apoptosis was monitored. A mathematical model has been formulated to describe changes in the concentration of uninfected and infected adherent cells, dynamics of virus particle release (infectious virions, hemagglutinin content), and the time course of the percentage composition of the cell population. 相似文献
9.
Background: Previous studies investigated extreme stress of ambulance personnel, where post-traumatic stress disorder dominated as far as the consequences were concerned. Recent studies are being led by the assumption that daily stress can increase the vulnerability with regard to psychological and health impairments. Aim: In the study, the main focus is placed on which daily stress exposures are of importance in the fire brigade and how they correlate with the personal health of the fire fighters. Burnout and the reduced habitual physical well-being are being examined as potential impairments. Method: Data was gathered from fire fighting personnel working in Berlin and Saxony-Anhalt by means of a questionnaire. Responses of 364 (response rate 40%) fire fighting personnel were analyzed by performing univariate, bivariate and multivariate analyses. A frame model “stress — burnout — physical well-being” is examined by using structural equation modelling (Lisrel). Results: Work-related obstacles in every-day life are of the greatest importance in the fire brigade’s daily work; extreme stress is being experienced rather seldom in comparison. Unfavorable general conditions of work organization correlate with higher burnout levels. The analyzed frame model — work-related stress influences burnout, burnout as an predictor for impairments of well-being — exhibits a satisfactory level of model fit. Conclusions: The results support the assumption that burnout has an intermediating effect on the relation of work-related stress and health. Therefore, the possibility of achieving a reduction of work organizational stress in order to lower the probability of long-term health impairments exists in the fire brigade. 相似文献
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