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11.
Pyelography is superior to all other imaging techniques for the demonstration of fine detail in the pelveocalyceal system and the ureter. For almost 90 years it has been performed through a retrogradely inserted catheter, but during the recent 30 years antegrade injection via a transparenchymally inserted needle or catheter has become an accepted alternative, especially in case of a dilated upper urinary tract. Both methods have their advantages and their disadvantages. This article presents a review of indications, techniques, and complications. Furthermore, interventional procedures on the upper urinary tract--such as stent placement and balloon dilatation--are now handled by the radiologist, mainly through an antegrade approach. These therapeutic procedures are also reviewed. 相似文献
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13.
Thomas B?llingtoft Knudsen Simon Francis Thomsen Charlotte Suppli Ulrik Mogens Fenger Steen Nepper-Christensen Vibeke Backer 《The Journal of asthma》2007,44(4):257-260
BACKGROUND: Season of birth (SOB) has been regarded as a risk factor for atopy. The aim of this study was to explore the relationship between season of birth (SOB) and later development of atopic disease in children and adolescents. METHODS: A total of 1,007 randomly selected subjects, 7 to 17 years of age, who were living in urban Copenhagen, Denmark were studied. All participants were interviewed about respiratory symptoms and possible risk factors for atopic disease. Skin test reactivity, serum total immunoglobulin E (IgE), and airway responsiveness were measured using standard techniques. RESULTS: The overall risk of atopy, as judged by skin test reactivity and serum total IgE, was the same regardless of SOB. On the contrary, asthma was more common in subjects born in the autumn compared with subjects born during the remaining part of the year (12.4% vs. 5.6%), OR = 2.40, 95% CI (1.56-3.94), p < 0.001. This was observed both for atopic asthma OR = 2.41, 95% CI (1.25-4.64), p = 0.007, non-atopic asthma, OR = 2.35, 95% CI (1.14-4.83), p = 0.02, and house dust mite (HDM) sensitive airway hyperresponsiveness, OR = 3.00, 95% CI (1.44-6.24), p = 0.002. Rhinitis and pollen allergy were not significantly related to SOB. CONCLUSIONS: Atopy itself is independent of season of birth, whereas asthma is more prevalent among subjects born during the autumn. Regarding asthma, these results suggest that the first months of life enclose a period of particular vulnerability towards environmental risk factors, especially exposure to aeroallergens like HDM. 相似文献
14.
False-Positive Computed Tomographic Findings in a Series of 525 Patients with Acoustic Neuromas
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In our series of 525 patients operated on for acoustic neuroma, there were three false-positive computed tomography findings resulting in unnecessary surgery. The histories and results of laboratory investigations and surgery are presented. Discussion of the outcome had gadolinium-enhanced magnetic resonance imaging been performed is presented. 相似文献
15.
F St?hlberg A Ericsson B Nordell C Thomsen O Henriksen B R Persson 《Acta radiologica (Stockholm, Sweden : 1987)》1992,33(3):179-200
The present work is intended as a nonmathematical review of the role of flow and motion in nuclear magnetic resonance (MR) imaging. A historical review of MR flow measurement techniques is given, followed by a short overview of flow models in vitro and in vivo. The theory behind the influence of motion on the modulus and phase MR signal information is discussed and effects such as washin/washout, flow-induced signal void, phase offset, and phase dispersion are defined. A simple approach to the concept of MR angiography is given, and methods for quantitative flow measurements such as the phase mapping technique, are surveyed. Aspects of the measurement of diffusion and microcirculation are given, and finally, an overview of the role of MR flow imaging in present and future clinical application is given. 相似文献
16.
An important methodological issue in depressionanalog research is whether individuals who scoreextremely low on self-report measures like the BeckDepression Inventory (BDI) should be included innondepressed control groups. Joiner, Schmidt, and Metalsky(1994) found that college students with BDI scores of 0or 1 evidenced a fake-good test taking style as measuredby the MMPI validity scales. The present study investigated whether very low BDI scores (BDI= 0 or 1; n = 21) might be associated with an elevatedpositive mood state, extreme optimism, positiveattributional style or social desirability. Resultsindicated that the very low scoring BDI subjects scoredhigher on social desirability than the low scoring group(BDI = 2 9, n = 63). Significant differences on mood,symptom and cognitive measures disappeared when social desirability was entered as a covariate.Findings support Kendall, Hollon, Beck, Hammen, andIngram's (1987) recommendation that subjects who score0 or 1 on the BDI should be excluded from a nondepressed control group. 相似文献
17.
S V Morán B Chuaqui M J Irarrázaval P Thomsen M Navarro J Urzúa G Maturana 《The Annals of thoracic surgery》1986,41(1):79-84
Potassium cardioplegia was compared with normothermic, intermittent ischemic arrest in 30 patients undergoing multiple coronary artery bypass grafts. Group 1 comprised 15 patients in whom cold potassium cardioplegia with St. Thomas' Hospital solution was used. In Group 2 were 15 patients who underwent intermittent ischemic arrest during the construction of the distal anastomoses. Two myocardial transmural left ventricular biopsies were done in each patient. There was no operative mortality. Electron microscopical examination showed normal myocardial ultrastructure in both groups. In particular, mitochondria were well preserved in all samples. The postoperative electrocardiogram demonstrated a new Q wave in 1 patient in Group 2 whose level of the myocardial isoenzyme of creatine phosphokinase (CPK-MB) was within the normal range. The peak CPK-MB release in Group 1 was 23.2 +/- 20.1 IU and in Group 2, 19.9 +/- 15.1 IU. This difference was not statistically significant. The mean period of anoxic arrest in Group 1 was 49.5 +/- 15 minutes and in Group 2, 25.5 +/- 8 minutes (p less than 0.001). Total cardiopulmonary bypass time in Group 1 was 114.5 +/- 20 minutes and in Group 2, 90.2 +/- 16 minutes (p less than 0.01). It is concluded that both techniques can preserve myocardial subcellular architecture during multiple coronary artery bypass grafting in patients with normal left ventricular function. 相似文献
18.
Obsessive-compulsive symptoms in children and adolescents. A phenomenological analysis of 61 Danish cases 总被引:1,自引:0,他引:1
P H Thomsen 《Psychopathology》1991,24(1):12-18
The charts of 61 children and adolescents admitted to the Psychiatric Hospital for Children in Aarhus, Denmark, in the period 1970-1986 fulfilling the DSM-III criteria for obsessive-compulsive disorder were reviewed for obsessive/compulsive symptoms. The symptoms were divided into form and content. The most common form of compulsion was rituals seen in 39 of the patients, and the most common compulsive content was washing. The most frequent obsessive content was thoughts about dirt and contamination followed by concern about death, illness and harm. The phenomenological feature of boys and girls was very similar, and only a few significant differences between boys and girls were found. One quarter of the boys and 12.5% of the girls had only obsession, whereas 27.0% of the boys and 37.5% of the girls had only compulsion and no obsession. The number of obsessive/compulsive symptoms was not found to correlate with the time spent each day on the symptom. It is concluded that there do not seem to be any intercultural differences between Denmark, India, and Japan as to the content of obsessional thoughts and compulsive behaviour in children and adolescents. 相似文献
19.
In a retrospective study, 1.173 fractures of the proximal femur, which had been treated surgically, were analysed in two periods from 1975 to 1991 and from 1992 to 2000. The influence on mortality of preoperative risk factors and primary treatment with total hip replacement (THR), even in cases of pertrochanteric fractures, was analysed by stepwise logistic regression. In the later period, mortality within 90 days was 13.1%, and within 1 year 22.2%. Rejection of hemiendoprosthesis in high-risk patients with intracapsular fractures increased the mortality rate from 6.3% to 11.8%. The introduction of dynamic hip screws instead of Ender nails led to a reduction of mortality from 16.5 to 7.1%. Higher mortality after THR (27.6%) compared to osteosynthesis (15.5%) in pertrochanteric femur and lateral neck fractures was due to higher age and increased risk factors. Although the influence of some risk factors could be reduced, age, sex and morbidity influenced the outcome more than surgical treatment. THP, even after pertrochanteric fractures, is reasonable if it guarantees a quick and enduring mobilisation of the patient. Bicentric bipolar prostheses are recommended for high risk patients. 相似文献
20.
H S Thomsen K Rasmussen F Burcharth S L Nielsen 《Acta radiologica (Stockholm, Sweden : 1987)》1988,29(1):138-140
The perfusion of two pancreatic transplants were examined three times a week for the first five postoperative weeks by intravenous angiography using 99Tcm-pertechnetate. Worsening of the perfusion always preceded or was associated with deterioration of the pancreatic function. Accordingly, radionuclide angiography may have an important place in the systematic monitoring of pancreatic transplants in the critical postoperative period. 相似文献