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141.
It has been suggested that environmental exposures and living conditions can explain some of the worldwide variation in atopic disorders. Norway has large environmental contrasts within the country. We compared skin prick sensitization rates among school children living in the southern subarctic and in the northern artic part of Norway. Approximately one quarter of the children were sensitized, mostly against pollen and animal dander, while mite and mould sensitization seemed to be a minor problem. Sensitization rates and profiles were similar in the north and south despite differences in living conditions and environmental exposures.  相似文献   
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A total of 779 patients operated on for vestibular schwannoma mostly by the translabyrinthine approach in Denmark during the period 1976-2000 answered a questionnaire about various postoperative consequences. In this paper we describe the patients' facial function evaluated by professionals one year postoperatively and self-evaluated by each patient according to the House-Brackmann scale at the time of the questionnaire. The patients' self-evaluation was more pessimistic than that of the professionals with 26% reporting House-Brackmann grade IV-VI, compared with 20%. One hundred and seventeen (15%) of 779 patients considered their facial palsy to be a big problem and 125 patients (16%) were interested in surgical treatment for the sequelae of facial palsy. Seventy-eight (10%) had already had some kind of operation, usually the VII-XII coaptation. Thirty-three of 61 patients who had already been operated on for facial palsy were interested in further surgical treatment. One hundred and ninety-five patients (25%) had some kind of operation on the eye, mostly (88%) a tarsorrhaphy. Reanimation procedures such as a palpebral gold weight or a spring, apparently still have a small place in Denmark. In conclusion, there seem to be a considerable and unmet need for surgical reanimation of facial function in patients with facial palsy after operations for vestibular schwannoma in Denmark.  相似文献   
147.
Inhaled chemical toxicants can damage the lungs during two phases: (1) the first-pass phase, in which toxicants are initially absorbed through the air/blood barrier, or (2) the circulation-transport phase, in which toxicants are transported back through the lungs with the circulating blood. While respiratory-tract dosimetry for inhaled toxicants is relatively easy to evaluate for the circulation-transport phase, it is more problematic for the first-pass phase and can involve higher local concentrations of toxicants. This article describes a respiratory-tract dosimetry model that simulates both the rate of absorption and the local concentration of low-volatile organic toxicants in the airway mucosa. The model simulates the non-steady-state diffusion of organic solutes from the air interface through the epithelium and into the capillary bed below. Cellular tissues are described as a heterogeneous, two-phase medium, with a minor lipid phase dispersed in a major aqueous phase. Results show that the lipid-phase/aqueous-phase partition coefficient, PC L/A', is a critical factor in determining the rate of absorption of solutes in the airway mucosa. For a PC L/A in the range 1 to 100, absorption is limited by blood flow and occurs with typical half-times from about 1 to 10 min. As PC L/A increases above 100, absorption is gradually limited by the rate of diffusion through the air/blood barrier, and absorption half-times increase to hours. Over the same range, the concentration gradient in the mucosa changes from almost uniform to more nonuniform, and the site-of-entry epithelium becomes more selectively exposed. As a result, with increasing PC L/A', protoxicants of lower reactivities can still be activated in significant quantities in the airway epithelium and thus act as site-ofentry toxicants. The presented results are important for understanding exposure/target-dose relationships of chemical carcinogens and for conducting reliable risk assessments.  相似文献   
148.
Background: Clinimetrics was introduced three decades ago to specify the domain of clinical markers in clinical medicine (indexes or rating scales). In this perspective, clinical validity is the platform for selecting the various indexes or rating scales (macro-analysis). Psychometric validation of these indexes or rating scales is the measuring aspect (micro-analysis). Methods: Clinical judgment analysis by experienced psychiatrists is included in the macro-analysis and the item response theory models are especially preferred in the micro-analysis when using the total score as a sufficient statistic. Results: Clinical assessment tools covering severity of illness scales, prognostic measures, issues of co-morbidity, longitudinal assessments, recovery, stressors, lifestyle, psychological well-being, and illness behavior have been identified. Conclusion: The constructive dialogue in clinimetrics between clinical judgment and psychometric validation procedures is outlined for generating developments of clinical practice in psychiatry.  相似文献   
149.
Axillary plexus blocks (AXB) are widely used for upper limb operations. It is recommend that AXB should be performed using a multiple injection technique. Information about the course and position of the musculocutaneous nerve (MCN) is of relevance for AXB performance. The objective of this study was to examine the position of the MCN and its relationship to the axillary sheath using MRI. 54 patients underwent an AXB with 40 ml of local anaesthetic before MRI examination. The course of the MCN and the position where it left the axillary sheath and perforated the coracobrachial muscle (MCN exit point), in relation to the axillary artery and the block needle insertion point in the axillary fold, were recorded. The MCN was seen clearly in 23, partly in 26, and not identified in five patients at the MCN exit point. The mean distance from the insertion point of the block needle in the axillary fold to the MCN exit point was 36.8 mm (SD = 18.9, range: 0–90.5). In 37 patients the MCN exit point was positioned inside the Q1 quadrant (lateral anterior to the axillary artery) and in 11 patients inside the Q2 quadrant (medial anterior to the axillary artery). There is a wide variability as to where the musculocutaneous nerve (MCN) leaves the axillary sheath. Therefore multiple injection techniques, or the use of a proximally directed catheter, should be appropriate to block the MCN.  相似文献   
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