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The aim of this study was to evaluate the pathological significance of antibodies against cornea and inner ear tissue in the development of audiovestibular and ocular symptoms in patients with Cogan's syndrome (CS). We analysed the serum of 5 CS patients for binding of IgM and IgG to fresh cryosections of rat labyrinth (semicircular canals, ampulla, utricle, saccule) and cornea by indirect immunofluorescence (IF). The predominant pattern of anti-corneal IgM was staining of the superficial cell layer of the non-keratinizing squamous epithelium. IgM against cornea was found in 3 patients, all of whom had bilateral inflammatory eye signs at the start of the disease. However, IgM was also detected in the chronic stage of the disease when no clinical signs of eye involvement were apparent. The study includes the first follow-up examination of anti-corneal IgM and IgG antibodies during a complete episode of active CS. During the first episode of CS in 1 patient, anti-corneal IgM became detectable 1 week after the onset of interstitial keratitis and 3 weeks after the onset of audiovestibular symptoms. It increased over several weeks and then fell to very low levels. However, at no time was anti-corneal IgG found. In the course of follow-up examinations, the serum of 4 patients intermittently contained low titre IgG antibodies against inner ear labyrinthine tissue, but without any clear correlation with the active stages of CS. In addition, high-resolution MRI (HR-MRI) of the inner ear was performed in the acute and chronic stages of CS to evaluate the activity of CS. In the acute stage, HR-MRI revealed abnormal MRI signals in the vestibule, semicircular canals, vestibular nerve, or cochlea. In the chronic stage, patients showed narrowing or occlusion of semicircular canals and the cochlea on the 3D-CISS images, but no high signal lesions (T1) and no enhancement. Antibodies against cornea or labyrinthine tissue were not consistently detected in CS and the level of organ-specific antibodies did not correlate with the activity of the disease.  相似文献   
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Summary -Adrenoceptor-mediated coronary vasoconstriction contributes to the initiation and aggravation of experimental and clinical myocardial ischaemia. However, the extent of 1- and 2-adrenoceptor-mediated constriction has not been characterized in the porcine coronary circulation despite the frequent use of this experimental model.Fifteen swine were anaesthetized with either -chloralose, enflurane or isoflurane to determine the amount of -adrenoceptor-mediated coronary constriction elicited by either the selective 1-adrenoceptor agonist methoxamine or the selective 2-adrenoceptor agonist azepexole. The left anterior descending coronary artery was cannulated and perfused by an external pump delivering constant blood flow from the carotid artery. Following bilateral cervical vagotomy and ß-adrenoceptor blockade with propranolol (2 mg kg–1), graded dosages of either one of the -adrenoceptor agonists (9–45 g kg–1 min–1) were infused into the coronary perfusion line while coronary arterial pressure (CAP) was measured through a distal side arm of the cannula to detect changes in coronary vascular resistance. Infusion of the -adrenoceptor agonists was terminated when systemic arterial pressure increased. Sonomicrometers were used to measure anterior left ventricular wall thickening for the assessment of regional contractile function. During methoxamine infusion, no increase in vascular resistance was observed during -chloralose, enflurane or isoflurane anaesthesia, whereas the infusion of azepexole increased CAP from 103 ± 31 mmHg to 120 ± 35 mmHg (-chloralose), from 101 ± 16 mmHg to 122 ± 11 mmHg (enflurane) and from 84 ± 20 mmHg to 94 ± 19 mmHg (isoflurane), respectively. In four additional swine anaesthetized with enflurane, the intracoronary infusion of the full catecholamine agonist noradrenaline in the presence of propranolol (6 mg kg–1) increased CAP from 98 ± 10 to 105 ± 10 mmHg prior to an increase in regional left ventricular function or systemic arterial pressure.These results indicate that there are no 1- and relatively little 2-adrenoceptor-mediated coronary constrictive effects in swine. Furthermore, neither -adrenoceptor agonist produced any detectable change in regional myocardial contractile function, regardless of the anaesthesia used.Supported by the German Research Foundation (He 1320/3-2). Dr. Guth is the recipient of a scholarship from the Alexander von Humboldt-Foundation. Send offprint requests to G. Heusch at the above address  相似文献   
999.
Due to the requirement to minimise exposure to radiation, it is desirable to develop non-ionising imaging procedures for the analysis of skeletal maturation for forensic age diagnostics in living individuals. The present pilot study analyses the applicability of ultrasound examinations for the evaluation of apophyseal ossification of the iliac crest. With reference to the sonographic staging of clavicular ossification, the maturation stages of the iliac crest apophysis of 23 male and 16 female subjects, aged 11–20 years, were determined. Ossification stage I occurred in the male subjects at a minimum age of 15.7 years. Ossification stage II was diagnosed in boys at a minimum age of 14.1 years and in girls at a minimum age of 11.7 years. The earliest observation of ossification stage III was at a chronological age of 16.2 years in males and 15.2 years in females. The earliest age of occurrence of ossification stage IV was at least 18.0 years in male test persons and at least 17.1 years in female test persons. The results obtained should be reassessed in a larger number of cases. It is to be expected that sonographic examination of the iliac crest apophysis will become established as a valid and efficient method for forensic age diagnostics in living individuals.  相似文献   
1000.
The experiments concerned the association of opioid dependence with specific opioid receptors. Previous investigations have demonstrated that tolerance may be confined to only one type of opioid receptor. These findings could suggest that dependence develops invariably only with receptors which have been rendered tolerant. We report here that in the guinea-pig isolated ileum, which has been made selectively tolerant to a μ-receptor agonist, naloxone may precipitate a sign of dependence at μ-receptors chronically activated and at naive κ-receptors. Furthermore, suppression of the withdrawal contracture in preparations rendered dependent on a μ-receptor agonist can be achieved by very low concentrations of a κ-agonist, e.g. dynorphin A. These findings challenge the current concept that confines drug dependence only to that opioid receptor type which has been activated chronically.  相似文献   
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