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A number of novel pyridazinomorphinans have been synthesized by the inverse electron demand Diels-Alder reaction of various 3,6-disubstituted 1,2,4,5-tetrazines with enamines derived from dihydrocodeinone and with codeinone. Reduction of some of the pyridazinomorphinans did not furnish the expected pyrroloepoxymorphinans; in all cases investigated reductive cleavage of the epoxybridge was observed to yield dihydropyridazino- or pyrrolomorphinans. The structures of all new compounds were assigned by the spectral data, that of the cycloadduct of codeinone was additionally verified by X-ray crystallography. Compounds 5a, 8, 11a , and 16 have been evaluated for their affinity at μ and κ opioid receptors in radioligand binding assays. Their ability to inhibit [3H]DAMGO binding at μ and [3H]U 69.593 binding at κ receptors, respectively as compared to codeine has been found to be lower.  相似文献   
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Noninvasive imaging techniques might be of particular diagnostic value for studying and monitoring cutaneous inflammatory conditions such as contact dermatitis. We evaluate acute allergic contact dermatitis (AACD) by means of optical coherence tomography (OCT) and correlate the clinical grading of patch test reactions with the findings obtained from OCT. Twenty positive patch test reactions (+, n = 6; ++, n = 7; +++, n = 7) are investigated using a conventional OCT scanner. In comparison to the control sites, OCT of AACD showed pronounced skin folds, thickened and/or disrupted entrance signals, and a significant increase in epidermal thickness. Moreover, clearly demarcated signal-free cavities within the epidermis and considerable reduction of dermal reflectivity are demonstrated by OCT. Notably, the latter findings strongly correlate with the clinical patch test grading. OCT may be a useful tool for visualization of micromorphological features of AACD. However, before OCT can be employed as an objective parameter in grading severity of patch test reactions, larger studies are required that correlate clinical patch test readings and OCT findings with histopathology.  相似文献   
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Mouse models of atopic eczema critically evaluated   总被引:2,自引:0,他引:2  
Atopic eczema (AE) is a chronic relapsing inflammatory skin disorder with increasing prevalence in Western societies. Even though we have made considerable progress in understanding the cellular and molecular nature of cutaneous inflammation, the precise pathomechanisms of AE still remain elusive. Experimental animal models are indispensable tools to study the pathogenic mechanisms and to test novel therapeutic approaches in vivo. For AE a considerable number of mouse models have been proposed and have been used to study specific aspects of the disease, such as genetics, skin barrier defects, immune deviations, bacteria-host interactions or the role of cytokines or chemokines in the inflammatory process. While some models closely resemble human AE, others appear to reflect only specific aspects of the disease. Here we review the currently available mouse models of AE in light of the novel World Allergy Organization classification of eczematous skin diseases and evaluate them according to their clinical, histopathological and immunological findings. The pathogenetic analogies between mice and men will be discussed.  相似文献   
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Macrolide-resistant Helicobacter (H.) pylori represent an increasing therapeutic problem. Macrolide resistance is usually determined phenotypically in vitro with methods such as E-test or agar dilution test. A prerequisite for those tests, however, is bacterial culture that is not routinely set up in the course of gastroscopy. In contrast, formalin-fixed, paraffin-embedded biopsies are regularly available from patients who have undergone gastroscopy. In such biopsies macrolide-resistant H. pylori can be detected by the genotype-based technique of fluorescence in situ hybridization (FISH). Experience gained by this new method, however, is still extremely limited, especially in formalin-fixed tissue. Therefore, we retrospectively investigated formalin-fixed, paraffin-embedded biopsy specimens by FISH in 104 patients suffering from therapy-resistant H. pylori gastritis. To test the accuracy of FISH, we initially examined specimens from 53 patients for whom results of the E-test were available. Next we analyzed biopsies from another 51 patients that had been selected since phenotypical resistance testing had failed despite documented culturing attempts. In all 104 patients, H. pylori was detected by FISH and could thus be investigated for macrolide resistance. Overall, macrolide-resistant bacteria were found in 71 patients (68.3%). In 49 of 53 patients (92.4%), FISH and E-test returned identical results (no significant discordance according to McNemar's chi(2)-test). Taken together, our study demonstrates that FISH is a highly sensitive and reliable method for detecting macrolide-resistant H. pylori in formalin-fixed, paraffin-embedded biopsy specimens, which represents the routine method of processing tissue obtained upon gastroscopy.  相似文献   
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Large-field motion of the visual environment is a powerful stimulus to induce the perception of contra-directional self-motion in a stationary observer. We investigated the interrelations between horizontal optokinetic nystagmus and subjective states of motion perception under variation of subjects' orientation with respect to gravity. Subjects were tested sitting upright and lying supine, and signalled transitions between object- and self-motion perception whilst viewing an optokinetic stimulus rotating about the subjects' longitudinal axis at a range of angular velocities. Optokinetic stimulation in the supine condition resulted in subjects perceiving a graviceptive conflict and the illusory perception of whole body tilt in a direction opposite to optokinetic stimulus rotation, whereas during upright viewing the axis of stimulus rotation was aligned with the direction of gravity and thus did not result in a conflict or perception of tilt. In both postures, self-motion perception coincided with an increased deviation of mean horizontal gaze position in the perceived direction of heading with a concurrent reduction in optokinetic nystagmus slow-phase gain. Slow-phase gain was also significantly reduced in the supine position as well as at increasing stimulus velocities. The results demonstrate that spontaneous transitions between the perception of object-motion and that of self-motion consistently coincide with spatial attentional and orientational strategies, shifting from passive monitoring to active oculomotor exploration and anticipation.  相似文献   
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