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排序方式: 共有360条查询结果,搜索用时 31 毫秒
1.
Precision of three-dimensional CT-assisted model production in the maxillofacial area 总被引:1,自引:0,他引:1
P. Solar C. Ulm W. Lill H. Imhof G. Watzek R. Blahout H. Gruber M. Matejka 《European radiology》1992,2(5):473-477
Individual skull model fabrication was introduced into preoperative diagnostics in maxillofacial surgery in the mid-1980s. The aim of the present study was to collect information on the reproducibility of a skull model milled from hardened polyurethane foam. This model was based on the CT data of a real skull. Twenty comparative studies were carried out on both the model and the original skull, the model showing an average inaccuracy of 1.6 mm. The deviations ranged between 0.0 and 3.6 mm; the general trend favouring enlargements. The total deviation of the model as compared to the original skull was 1.8%. A convincing aspect of the model, which cannot be obtained by any other method, is its plasticity and the possibility of 3 D orientation on a lifesize model. This new method is already used in preoperative planning of corrections of post-traumatic defects and craniofacial deformities as well as in tumour surgery.
Correspondence to: P. Solar 相似文献
2.
Wolfgang H Oertel Tobias W?chter Niall P Quinn Gudrun Ulm Dirk Brandst?dter 《Movement disorders》2003,18(4):430-432
According to the consensus statement on the diagnosis of multiple system atrophy (MSA), erectile dysfunction is required for male patients to fulfil the urinary incontinence criterion. However, there is no equivalent item for female patients. We questioned 19 female patients with MSA of the parkinsonian type (MSA-P), 28 female patients with Parkinson's disease (PD), and 27 healthy controls on their genital sensitivity. A total of 47% of the MSA patients but only 4% of the PD patients and 4% of the control group admitted to reduced genital sensitivity, a highly significant difference (P < 0.001). Moreover, the appearance of reduced genital sensitivity in female MSA patients showed a close temporal relation to the onset of the disease. If these preliminary results can be confirmed and further specified in a larger sample, a historical item of reduced genital sensitivity in female patients might become a diagnostic feature for MSA, comparable to erectile dysfunction in male patients. 相似文献
3.
Y F Posey D Shah J E Ulm K T Bastin F F Parl J A Phillips 《American journal of clinical pathology》1989,92(3):347-351
The prenatal diagnosis of sickle cell anemia (hemoglobin SS) can be established by DNA analysis using two highly sensitive techniques (Southern blot and polymerase chain reaction [PCR]). Hemoglobin electrophoresis provides a third, simpler and more rapid, technique to analyze blood from a fetus at risk for sickle cell anemia. The authors present examples of prenatal diagnostic studies using both DNA analysis techniques and hemoglobin electrophoresis. Hemoglobin electrophoresis of fetal hemolysate can provide a simple and rapid alternative method to PCR analysis for the prenatal exclusion of sickle cell anemia, and it is especially useful in cases in which rapid results are needed because of advanced gestational age. 相似文献
4.
Silica dust and lung cancer in the German stone, quarrying, and ceramics industries: results of a case-control study
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BACKGROUND: A work force based case-control study of lung cancer was performed in non-silicotic subjects exposed to crystalline silica to investigate the association between silica dust and lung cancer excluding the influence of silicosis. METHODS: Two hundred and forty seven patients with lung cancer and 795 control subjects were enrolled, all of whom had been employed in the German stone, quarrying, or ceramics industries. Smoking was used as a matching criterion. Exposure to silica was quantified by measurements, if available, or otherwise by industrial hygienists. Several indices (peak, average and cumulative exposure) were used to analyse the relationship between the level of exposure and risk of lung cancer as odds ratios (OR). RESULTS: The risk of lung cancer is associated with the year of and age at first exposure to silica, duration of exposure, and latency. All odds ratios were adjusted for these factors. Considering the peak exposure, the OR for workers exposed to high levels (>/=0.15 mg/m3 respirable silica dust which is the current occupational threshold value for Germany) compared with those exposed to low levels (<0.15 mg/m3) was 0.85 (95% CI 0.58 to 1. 25). For the time weighted average exposure the OR was 0.91 (95% CI 0.57 to 1.46). The OR for the cumulative exposure was 1.02 (95% CI 0. 67 to 1.55). No increase in risk was evident with increasing exposure. CONCLUSIONS: This study shows no association between exposure to crystalline silica and lung cancer. The exclusion of subjects with silicosis may have led to dilution with respect to the level of exposure and therefore reduced the power to detect a small risk. Alternatively, the risk of getting lung cancer may be restricted to subjects with silicosis and is not directly linked to silica dust. 相似文献
5.
In 45 patients with Parkinson's disease, we investigated coping behavior and its correlations to demographic and disease-related data, locus of control, depression, and psychosocial adaptation. Active, problem oriented, and self-reorganizing strategies were predominantly used and regarded as especially helpful by the 27 men and 18 women (age: 56 years; duration of illness: 9 years). While age and sex were not associated with coping, external locus of control correlated positively to "depressive coping" and duration of illness correlated negatively to "distraction and self-affirmation." Coping strategies regarded as maladaptive and a small degree of internal locus of control correlated to unfavourable results for depression and satisfaction. 相似文献
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7.
Mortality rates in the Federal Republic of Germany following previous occupational exposure to asbestos dust 总被引:3,自引:0,他引:3
H. -J. Woitowitz H. -J. Lange L. Beierl M. Rathgeb K. Schmidt K. Ulm T. Giesen R. H. Wohowitz L. Pache K. Rödelsperger 《International archives of occupational and environmental health》1986,57(3):161-171
Summary In 1972, a procedure was introduced by the Industrial Injuries Insurance Institutes (Berufsgenossenschaften) of the Federal Republic of Germany, which is to be used by the special occupational health service for employees exposed to asbestos dust. Since 1 January 1972, occupational health examinations are performed when exposure to asbestos dust has been of at least 3 years' duration.On 1 January 1977, a prospective cohort study was started with employees formerly exposed to asbestos dust whilst working for companies manufacturing or using asbestos. Data on these persons are collected in the Central Register of Employees Exposed to Asbestos Dust of the Industrial Injuries Insurance Institutes. A total of 3,070 male and female employees in whom asbestos exposure terminated after 1 January 1972 formed subcohort I of the study. For comparison, 665 persons whose exposure terminated before 1 January 1972 served as subcohort II. In addition to several other inclusion criteria, each individual's permission was required before personal data could be evaluated.Of the subjects in the two subcohorts, 185 and 71, respectively, had died by 31 December 1982. Tumours were more frequently than this cause of death is expected in the general population. In addition to a high incidence of mesothelioma, the standard mortality rate was especially increased for lung cancer.The proportional mortality rates of about 40% for tumours of all sites (with about 17% lung cancer and 8% mesothelioma) especially in subcohort II, seemed to be comparable to the international figures for epidemiological mortality.Supported by the Central Office of the Industrial Injuries Insurance Institutes, Bonn, Contract no.638.31:376.3-4104.Presented as a Short Communication at the XXI International Congress on Occupational Health, Dublin, September 9–14, 1984. 相似文献
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The effect of mitral valve closure on left ventricular filling time and its relation to the onset of systole were assessed from mitral valve echocardiograms and simultaneous apex cardiograms in 21 normal subjects, 11 patients with left bundle branch block, and 19 patients with VDD pacemakers programmed for atrioventricular intervals of 50, 150, and 250 ms. The interval between the electrocardiograph Q wave and the apex cardiogram upstroke was similar in normal subjects and patients with left bundle branch block, but was significantly longer in patients with VDD pacemakers at all atrioventricular intervals. Similarly there was little difference in the time interval between the Q wave and mitral valve closure in normal individuals and patients with left bundle branch block but this was considerably delayed in VDD pacemaker patients with the atrioventricular interval set at 50 ms. With increasing atrioventricular intervals the mitral valve closed significantly earlier, whereas the onset of left ventricular systole and the timing of mitral valve opening remained unchanged. Thus as a result of earlier mitral valve closure left ventricular filling time decreased progressively as the atrioventricular interval was increased. Since the onset of left ventricular systole, with respect to left ventricular stimulation, is considerably delayed in VDD pacemaker patients a short atrioventricular interval is required in these patients to maintain the normal time relations between atrial and ventricular contraction and hence maximise left ventricular filling. 相似文献