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We have previously reported that caffeine prevented sleep deprivation‐induced impairment of long‐term potentiation (LTP) of area CA1 as well as hippocampus‐dependent learning and memory performance in the radial arm water maze. In this report we examined the impact of long‐term (4‐week) caffeine consumption (0.3 g/L in drinking water) on synaptic plasticity ( Alhaider et al., 2010 ) deficit in the dentate gyrus (DG) area of acutely sleep‐deprived rats. The sleep deprivation and caffeine/sleep deprivation groups were sleep‐deprived for 24 h by using the columns‐in‐water technique. We tested the effect of caffeine and/or sleep deprivation on LTP and measured the basal levels as well as stimulated levels of LTP‐related molecules in the DG. The results showed that chronic caffeine administration prevented the impairment of early‐phase LTP (E‐LTP) in the DG of sleep‐deprived rats. Additionally, chronic caffeine treatment prevented the sleep deprivation‐associated decreases in the basal levels of the phosphorylated calcium/calmodulin‐dependent protein kinase II (P‐CaMKII) and brain derived neurotrophic factor (BDNF) as well as in the stimulated levels of P‐CaMKII in the DG area. The results suggest that chronic use of caffeine prevented anomalous changes in the basal levels of P‐CaMKII and BDNF associated with sleep deprivation and as a result contributes to the revival of LTP in the DG region.  相似文献   
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995.
The objective of this investigation was to evaluate the reliability of classification systems by determining inter- and intraobserver agreement in displaced distal radius fractures. Radiographs of 32 patients (21 men and 11 women with a mean age of 41.6 years) who presented with a displaced distal radius fracture were classified by 9 orthopedic surgeons (5-25 years experience) using 5 different classification systems (Fernandez, AO, Frykman, Melone, and Universal Classification systems) twice with 20-day intervals. The results were processed with kappa statistics and used in assessment of inter- and intraobserver agreement of the classification systems. When classification systems were compared, the highest kappa coefficient in intraobserver agreement was determined in Universal classification (0.621). Fernandez (0.474), AO (0.309), Frykman (0.305), and Melone classification systems (0.262) followed the Universal system respectively. Kappa statistical results were evaluated using the Landis Koch score system for the assessment of interobserver agreement. According to the Landis Koch score system, the results were insufficient in all classification systems. Fernandez classification system had the highest interobserver agreement (0.235) and Melone classification system had the lowest interobserver agreement (0.056). According to the results of our study, the systems used to classify the displaced distal radial fractures are insufficient. A new classification system that ensures the 3-dimensional assessment of the fracture is more user-friendly and a high inter- and intraobserver agreement is necessary.  相似文献   
996.
Acute severe colicky pain in the flank region is termed as renal colic (RC), which is commonly diagnosed and treated in the emergency department (ED). The present study is designed to investigate the hospital costs of patients with RC admitted to the ED and factors affecting the figures. Retrospective analysis includes all patients diagnosed with RC following physical examination and X-ray, ultrasound, computed tomography together with laboratory investigations in the university-based ED between February 2007 and February 2009. The study included 574 patients eligible for the predefined criteria. Mean total hospital cost in patients admitted to the ED due to RC was calculated to be 55.77 Euro. The greatest contribution to the total cost was made by radiological investigations in the ED (40.5%) followed by treatment costs (19.7%). Size and location of the stone and stay times in the ED were the independent variables affecting the costs. The costs were higher as the stones were bigger and as they were more distal in the ureter. Renal stones were associated with the lowest hospital costs. Radiological investigations are the greatest contributors in the ED costs in patients with RC. Effective measures need to be undertaken to reduce resultant costs. Preventive measures as well as diagnostic and therapeutic procedures should be standardized in the ED in accordance with technological advances and also cost-effectiveness when appropriate.  相似文献   
997.

Background

Detailed knowledge of nerve distribution in the neurovascular bundle (NVB) is essential to preserve sexual function after prostatic surgery.

Objective

To identify the location as well as the type (adrenergic, cholinergic, and sensory) of nerve fibres within the NVB and to provide a three-dimensional (3D) representation of their structural relationship in the human male foetus.

Design, setting, and participants

Serial transverse sections were performed every 150–200 μm in the pelvic portion of six human male foetuses (15–20 wk of gestation). Sections were treated with histologic and immunohistochemical methods (hematin-eosin-safran, Luxol Fast Blue, immunolabelling of protein S100, vesicular acetylcholine transporter, tyrosine hydroxylase, calcitonin gene-related peptide, and substance P). The 3D pelvic reconstruction was obtained from digitised serial sections using WinSurf software.

Measurements

NVB nerve location and type were evaluated qualitatively.

Results and limitations

The 3D reconstruction allowed precise identification of pelvic organ innervation. Nerve fibres derived from the inferior hypogastric plexus followed two courses: posterior and lateral, providing cholinergic, adrenergic, and sensory innervation to seminal vesicles, vas deferens, prostate, and urethral sphincter. Cavernous nerve fibres did not strictly follow the NVB course; they were distributed at several levels, in a fanlike formation. The main limitations of this study were the limited number of specimens available due to legal restriction and the time-consuming nature of the manually performed stages in the method.

Conclusions

The distribution of nerve fibres within the posterolateral prostatic NVB and the existence of mixed innervation in the posterior and lateral fibre courses at the level of the prostate and seminal vesicles give us an insight into how to minimise effects on sexual function during prostatic surgery. The 3D computer-assisted anatomic dissection represents an original method of applying anatomic knowledge to surgical technique to improve nerve preservation and decrease postoperative sexual complications.  相似文献   
998.
999.
Upper-extremity deep vein thrombosis is common after pacemaker or cardioverter-defibrillator implantation. Only 1% to 3% of patients with upper-extremity deep vein thrombosis become symptomatic. Downhill esophageal varices develop in the upper third of the esophagus as a result of the obstruction of the superior vena cava. Herein, we report the case of a 54-year-old man--a recipient of multiple implanted cardiac pacemakers--who presented with bilateral upper-extremity deep vein thrombosis. This severely symptomatic condition was complicated by very rare and life-threatening downhill varices of the upper esophagus, but without bleeding. To the best of our knowledge, this is the 1st report of this array of conditions.  相似文献   
1000.
Video capsule endoscopy (VCE) that was launched 10 years ago has become a first-line procedure for examining the small bowel, especially in the case of obscure gastrointestinal bleeding. Other major indications include Crohn disease (CD), celiac disease, and intestinal polyposis syndrome. In the case of small bowel diseases, the use of VCE must be integrated in?a?global diagnostic and therapeutic approach. More recently, wireless endoscopy has been adapted for examining the colon, opening up larger perspectives for colorectal cancer screening or colon examination. Technologic modifications of the second-generation colon capsule increase the sensitivity of this method for detecting polyps. Other new developments, including remote magnetic manipulation, power management, drug delivery capsule, microbiopsy capsule, and adaptation of technologies such as chromoendoscopy, are sure to enhance the capabilities of wireless endoscopy in gastrointestinal disorders.  相似文献   
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