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71.
Abstract

Background: An association between sexually transmitted diseases (STDs) and occurrence of head and neck cancer (HNC) is proposed.

Aims/objectives: We aimed to determine the association between selected STDs (syphilis, gonorrhoea, HIV) and HNC.

Materials and methods: Patients diagnosed with HNC in Denmark between 1978 and 2014 identified through the Danish Cancer Registry were included. Patients were age- and sex-matched in a 1:10 ratio with general population controls. Uni- and multivariate analyses were performed using the Cox regression model to assess the correlation between STD and HNC.

Results: A total of 39,405 HNC patients (63% men; 63.0 years at HNC diagnosis) and 393,238 controls were included. STD in HNC patients was 0.27%, vs. 0.11% in controls. Patients with cancer of the upper airways had a significantly higher prevalence of an STD prior to the HNC compared to controls. Most HNC patients with a prior STD (64.1%) developed the HNC within five years after the STD diagnosis.

Conclusions: Although the studied STDs are rare, patients with cancer of the upper aerodigestive tract more commonly had a previous diagnosis of STD compared to controls. The study promotes the hypothesis that a causal link exists between STD and HNC.  相似文献   
72.
In atrioventricular rhythm the normal auricular pacemaker is inhibited and there is uncovered a secondary center from which impulses activate the ventricle and, in uncompleted cases, the auricle as well. In certain cases, however, impulses from the secondary center are not conducted to the auricle. In such instances auricular escape occurs, the auricular center of highest automaticity becoming the pacemaker for the auricle. The rhythmicity of such a secondary auricular center is subject to the same influence that may affect other centers of impulse formation. In some cases the retrograde blocking of impulses from the ventricular center is incomplete, and the auricular pacemaker is discharged prematurely by those impulses which reach it just before the completion of its automatic period. Impulses from this pacemaker pass not only to the auricle but also toward the ventricle and produce premature ventricular contractions when not interfered with by refractory tissue. Beating of the ventricle in response to impulses both from the ventricular pacemaker and from the auricular center in such cases constitutes parasystole.Ten cases were studied, three of which are reported in detail. Reciprocal rhythm as an explanation of the records in these cases is considered but evidence against this interpretation is presented. It appears that cases of simple A-V rhythm, of so-called reciprocal rhythm, and of parasystole are fundamentally related; the precise mechanism in a given instance being determined by the state of retrograde conductivity from the ventricular pacemaker.These cases occur under circumstances associated with sinus depression and lowered conductivity. Digitalis in some instances appears to be a contributory factor.  相似文献   
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This guideline is the result of a consensus reached during a panel discussion at the 2nd International Consensus Meeting on Urticaria, Urticaria 2004, a joint initiative of the European Academy of Allergology and Clinical Immunology Dermatology Section and the European Union (EU)-funded network of excellence, GA2LEN. It covers the definition and classification of urticaria, taking into account the recent progress in identifying causes, eliciting factors and pathomechanisms of this disease. We have outlined useful diagnostic approaches for different subtypes of urticaria. This guideline was, in addition, accepted by the European Dermatology Forum (EDF) and was formally approved by the European Union of Medical Specialists (UEMS).  相似文献   
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Recent research revealed a surprisingly large range of cognitive operations to be preserved during sleep in humans. The new challenge is therefore to understand functions and mechanisms of processes, which so far have been mainly investigated in awake subjects. The current study focuses on dynamic changes of brain oscillations and connectivity patterns in response to environmental stimulation during non-REM sleep. Our results indicate that aurally presented names were processed and neuronally differentiated across the wake-sleep spectrum. Simultaneously recorded EEG and MEG signals revealed two distinct clusters of oscillatory power increase in response to the stimuli: (1) vigilance state-independent θ synchronization occurring immediately after stimulus onset, followed by (2) sleep-specific α/σ synchronization peaking after stimulus offset. We discuss the possible role of θ, α, and σ oscillations during non-REM sleep, and work toward a unified theory of brain rhythms and their functions during sleep.SIGNIFICANCE STATEMENT Previous research has revealed (residual) capacity of the sleeping human brain to interact with the environment. How sensory processing is realized by the neural assemblies in different stages of sleep is however unclear. To tackle this question, we examined simultaneously recorded MEG and EEG data. We discuss the possible role of θ, α, and σ oscillations during non-REM sleep. In contrast to versatile θ band response that reflected early stimulus processing step, succeeding α and σ band activity was sensitive to the saliency of the incoming information, and contingent on the sleep stage. Our findings suggest that the specific reorganization of mechanisms involved in later stages of sensory processing takes place upon falling asleep.  相似文献   
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