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91.
AIM: To study adherence to the widely accepted surveillance guidelines for patients with long-standing colitis in the Netherlands. METHODS: A questionnaire was sent to all 244 gastroenterologists in the Netherlands. RESULTS: The response rate was 63%. Of all gastroenterologists, 95% performed endoscopic surveillance in ulcerative colitis (UC) patients and 65% in patients with Crohn's colitis. The American Gastroenterological Association (AGA) guidelines were followed by 27%, while 27% and 46% followed their local hospital protocol or no specific protocol, respectively. The surveillance was correctly initiated in cases of pancolitis by 53%, and in cases of left-sided colitis by 44% of the gastroenterologists. Although guidelines recommend 4 biopsies every 10 cm, less than 30 biopsies per colonoscopy were taken by 73% of the responders. Only 31%, 68% and 58% of the gastroenterologists referred patients for colectomy when low-grade dysplasia, high-grade dysplasia (HGD) or Dysplasia Associated Lesion or Mass (DALM) was present, respectively. CONCLUSION: Most Dutch gastroenterologists perform endoscopic surveillance without following international recommended guidelines. This practice potentially leads to a decreased sensitivity for dysplasia, rendering screening for colorectal cancer in this population highly ineffective.  相似文献   
92.

Introduction

Patients undergoing cardiac surgery with cardiopulmonary bypass (CPB) are susceptible to haemostatic disturbances. Monitoring the haemostatic capacity by conventional clotting tests is challenging.

Materials and Methods

Thrombin generation (TG) by Calibrated Automated Thrombography, clotting tests and tissue factor pathway inhibitor (TFPI) measurements were performed to describe the relationship between haemostatic changes and alterations in these tests. Blood samples were collected before, during and after CPB. Furthermore, it was investigated whether TG measured intraoperatively, is associated with increased risk of bleeding postoperatively.

Results

TG diminished significantly (p < 0.01) after heparinization in the presence and absence of platelets (37% and 50%) compared to baseline. After the start of CPB, TG elevated and persisted till the end of surgery but remained lower than preoperatively. Activated clotting time increased after heparinization and after the start of bypass compared to baseline (400% and 500%). Anti-FXa activity reduced on the start of CPB compared to the level after heparinization, to almost the baseline value following protamine reversal of heparin. The plasma levels of total and free TFPI elevated 9 and 14 fold during bypass and remained after protamine administration higher than preoperatively. Plasma D-dimer levels reduced (p < 0.01) when bypass started. However, a marked elevation was observed in the following time points. TG in platelet-rich plasma measured after heparinization and after the start of CPB associated (p < 0.05) with postoperative blood loss.

Conclusions

TG can be determined during CPB despite the high heparinization level, it reflects the haemostatic capacity better than clotting-based assays and might better predict bleeding when performed intraoperatively.  相似文献   
93.

Background

Reversible posterior leukoencephalopathy syndrome (RPLS) is radiologically characterized by symmetrical subcortical areas of vasogenic edema that are preferentially parieto-occipital, and it typically resolves after appropriate treatment.

Case Report

We present a patient with strikingly unilateral RPLS that developed 21 days after coiling of an anterior communicating artery aneurysm and several days of triple-H therapy. Cortical and subcortical vasogenic edema and enhancement developed only in the left hemisphere, with a pattern suggesting RPLS. After 7 months the lesions had nearly completely resolved.

Conclusions

The pathophysiological mechanism underlying RPLS is still not well understood, which makes it difficult to explain the unilateral appearance in this case. Since the imaging findings may be confused with other conditions such as ischemia, recognition of RPLS after coiling is necessary in order to avoid inadequate treatment.  相似文献   
94.

Objective

The purpose of this study is to examine the perforating arteries (PAs) in the proximal part of the posterior inferior cerebellar artery (PICA) for surgical approaches to the brain stem and fourth ventricle, and to stress their importance in microsurgical procedures.

Methods

Twenty-six adult cadaver obtained from routine autopsies were used. During the examination, the PAs and the segmental structure of the proximal part of the PICAs and their relation to the neighbouring anatomical structures were demonstrated.

Results

We classified the PICAs into 4 types on the basis of the distance of the middle point of the width of the caudal loop to the midline, and their presence or absence as Group A (symmetrical, anterior medullary type: 26.9%), Group B (lateral medullary type: 15.4%), Group C (asymmetrical type: 38.5%), and Group D (unilateral type: 19.2%). The number of the PAs in the tonsillomedullary segment and the caudal loop was higher than those originating from the other segments.

Conclusions

Approaches to the medial or lateral of the PICA should be made in a way that protects the PAs (avoiding retraction of the PICA). Otherwise the PAs will be damaged and as a result brain stem ischaemia may occur, which can have serious clinical outcomes.  相似文献   
95.
Astrocyte activation is an important feature in many disorders of the central nervous system, including chronic pain conditions. Activation of astrocytes is characterized by a change in morphology, including hypertrophy and increased size of processes, proliferation, and an increased production of proinflammatory mediators. The xanthine derivatives pentoxifylline and propentofylline are commonly used experimentally as glial inhibitors. These compounds are generally believed to attenuate glial activity by raising cyclic AMP (cAMP) levels and inhibiting glial tumor necrosis factor (TNF) production. In the present study, we show that these substances inhibit TNF and serum‐induced astrocyte proliferation and signaling through the mammalian target of rapamycin (mTOR) pathway, demonstrated by decreased levels of phosphorylated S6 kinase (S6K), commonly used as a marker of mTOR complex (mTORC) activation. Furthermore, we show that pentoxifylline and propentofylline also inhibit JNK and p38, but not ERK, activation induced by TNF. In addition, the JNK antagonist SP600125, but not the p38 inhibitor SB203580, prevents TNF‐induced activation of S6 kinase, suggesting that pentoxifylline and propentofylline may regulate mTORC activity in spinal astrocytes partially through inhibition of the JNK pathway. Our results suggest that pentoxifylline and propentofylline inhibit astrocyte activity in a broad fashion by attenuating flux through specific pathways. © 2012 Wiley Periodicals, Inc.  相似文献   
96.
Rubrospinal neurons (RSNs) undergo marked atrophy after cervical axotomy. This progressive atrophy may impair the regenerative capacity of RSNs in response to repair strategies that are targeted to promote rubrospinal tract regeneration. Here, we investigated whether we could achieve long-term rescue of RSNs from lesion-induced atrophy by adeno-associated viral (AAV) vector-mediated gene transfer of brain-derived neurotrophic factor (BDNF). We show for the first time that AAV vectors can be used for the persistent transduction of highly atrophic neurons in the red nucleus (RN) for up to 18 months after injury. Furthermore, BDNF gene transfer into the RN following spinal axotomy resulted in counteraction of atrophy in both the acute and chronic stage after injury. These novel findings demonstrate that a gene therapeutic approach can be used to reverse atrophy of lesioned CNS neurons for an extended period of time.  相似文献   
97.
Title.  Music-assisted relaxation to improve sleep quality: meta-analysis.
Aim.  This paper is a report of a meta-analysis conducted to evaluate the efficacy of music-assisted relaxation for sleep quality in adults and elders with sleep complaints with or without a co-morbid medical condition.
Background.  Clinical studies have shown that music can influence treatment outcome in a positive and beneficial way. Music holds the promise of counteracting psychological presleep arousal and thus improving the preconditions for sleep.
Data sources.  We conducted a search in the Embase (1997 – July 2008), Medline (1950 – July 2008), Cochrane (2000 – July 2008), Psychinfo (1987 – July 2008) and Cinahl (1982 – July 2008) databases for randomized controlled trials reported in English, German, French and Dutch. The outcome measure of interest was sleep quality.
Methods.  Data were extracted from the included studies using predefined data fields. The researchers independently assessed the quality of the trials using the Delphi list. Only studies with a score of 5 points or higher were included. A pooled analysis was performed based on a fixed effect model.
Results.  Five randomized controlled trials with six treatment conditions and a total of 170 participants in intervention groups and 138 controls met our inclusion criteria. Music-assisted relaxation had a moderate effect on the sleep quality of patients with sleep complaints (standardized mean difference, −0·74; 95% CI: −0·96, −0·46). Subgroup analysis revealed no statistically significant contribution of accompanying measures.
Conclusion.  Music-assisted relaxation can be used without intensive investment in training and materials and is therefore cheap, easily available and can be used by nurses to promote music-assisted relaxation to improve sleep quality.  相似文献   
98.
99.
OBJECTIVE: To determine which thalamic subnuclei are involved in symptomatic unilateral movement disorders due to localized thalamic infarction, and the clinical characteristics of these abnormal movements. METHODS: The authors studied 22 patients with thalamic infarcts for their clinical presentation and the topography of the lesions, using three-dimensional T1-weighted MRI sequencing and stereotaxic analysis of the lesions. RESULTS: Patients were divided into four groups: 1) absence of abnormal involuntary movements (AIM) (nine patients); 2) isolated dystonic posture (two patients); 3) myoclonic dystonia (five patients); and 4) tremor or myoclonus (six patients). In patients with AIM, thalamic lesions were contralateral to the abnormal movements, involving the thalamogeniculate territory, centered on the ventral intermediate (Vim) and ventral caudal (Vc) nuclei. No significant difference in the volumes or center of mass of the lesions was found between patients with tremor and myoclonus and patients with dystonia, although the central nucleus and the internal part of the Vim nucleus were more consistently damaged in dystonic patients. CONCLUSION: Movement disorders related to thalamic lesions included: 1) myoclonic dystonia with predominating myoclonus and "thalamic" hand associating dystonic posture and slow, pseudo-athetoid movements, both related to lesions in the Vim and Vc nuclei of the thalamus; and 2) postural and action tremor, also related to lesions in the Vim, similar to tremor associated with midbrain lesions, as a result of abnormal functioning of the cerebello-thalamic pathways.  相似文献   
100.
The visual front-end of reading is most often associated with orthographic processing. The left ventral occipito-temporal cortex seems to be preferentially tuned for letter string and word processing. In contrast, little is known of the mechanisms responsible for pre-orthographic processing: the processing of character strings regardless of character type. While the superior parietal lobule has been shown to be involved in multiple letter processing, further data is necessary to extend these results to non-letter characters. The purpose of this study is to identify the neural correlates of pre-orthographic character string processing independently of character type. Fourteen skilled adult readers carried out multiple and single element visual categorization tasks with alphanumeric (AN) and non-alphanumeric (nAN) characters under fMRI. The role of parietal cortex in multiple element processing was further probed with a priori defined anatomical regions of interest (ROIs). Participants activated posterior parietal cortex more strongly for multiple than single element processing. ROI analyses showed that bilateral SPL/BA7 was more strongly activated for multiple than single element processing, regardless of character type. In contrast, no multiple element specific activity was found in inferior parietal lobules. These results suggests that parietal mechanisms are involved in pre-orthographic character string processing. We argue that in general, attentional mechanisms are involved in visual word recognition, as an early step of word visual analysis.  相似文献   
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