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991.
Purpose: To evaluate the characteristic features of mechanical responses and the membrane potential changes induced by repetitive pulsed electromagnetic field (PEMF, 50 Hz, 5 mT) in thoracic aorta rings obtained from streptozotocin-induced diabetic and healthy control rats to determine if PEMF could ameliorate problems associated with diabetes.

Methods: Sixty male Wistar rats weighing 250–290 g were randomly divided into two experimental groups, each containing 30 animals. Streptozotocin was given via tail vein to produce diabetes mellitus (DM) in the first group rats. The second group rats were treated only with % 0.9 saline and considered as non-DM group. Both groups were also divided into two subgroups as DM + PEMF, DM + sham, PEMF and sham, each containing 15 animals. Although the DM + PEMF and PEMF groups were treated, the DM + sham and sham groups were not treated with PEMF. The PEMF treatment occurred four times daily for 30 min at 15-min intervals repeated daily for 30 days. Thoracic aorta rings from both DM and non-DM rats exposed to PEMF were evaluated for contraction and relaxation responses and membrane potential changes in the presence or absence of chemical agents that were selected to test various modes of action.

Results: Relaxation response of thoracic aorta rings was significantly reduced in DM than non-DM group. PEMF treatment significantly increased the relaxation response of the diabetic rings to acetylcholine, and reduced the concentration response to phenylephrine. Resting membrane potential was significantly higher in DM than in non-DM group. Inhibitors of nitric oxide (NO), both nitro-L-arginine (L-NO-ARG) and L-NO-ARG + indometacin combination, produced a significant transient hyperpolarisation in all groups. Inhibitors of potassium channel activity, charybdotoxin or apamine, produced a membrane depolarisation. However, PEMF did not induce any significant effect on the membrane potential in DM group.

Conclusions: Diabetes reduced the relaxation response of thoracic aorta rings. It also affected the membrane potentials of the rings. Treatment with PEMF ameliorated the diabetes-induced impairments in the relaxation response of these rings.  相似文献   
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We aimed to evaluate the differences between apparent diffusion coefficient (ADC), fractional anisotropy (FA), axial diffusivity (AD), and radial diffusivity (RD) values obtained from different cranial sites in subjects with Chiari I Malformation (CM-I) and borderline tonsillar ectopia (BTE), and to determine correlations between diffusion tensor imaging (DTI) metrics and the severity of tonsillar ectopia. A total of 73 subjects with CM-I and BTE and 35 control underwent MRI and DTI. In our study, ADC values measured from the level of medulla oblongata and the RD values measured in middle cerebellar peduncles, thalamus, and globus pallidus were higher in CM-I patients than in controls. FA values at the medulla oblongata level and AD values at the medulla oblongata and pons level higher in patients with CM-I. ADC and AD values measured at the pons level were higher in BTE subjects than in controls. Compared with BTE, the CM-I subjects’ ADC values at the medulla oblongata and AD values at the pons level were higher. In addition, FAs at the pons and medulla oblongata level were higher. At the medulla oblongata level, a positive correlation was observed between ADC and the size of tonsillar ectopia. AD and FA values measured at the level of medulla oblongata and pons were positively correlated with the size of tonsillar ectopia. These findings may be related to the severity of microstructural changes involving neuronal tracts at the brainstem level due to tonsillar ectopia. DTI may be useful in determining the extent of microstructural changes at the tissue level in subjects with tonsillar ectopia.  相似文献   
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We report a case of reactive arthritis following tetanus vaccination. A healthy 55-year-old woman presented with pain and acute swelling of the right knee two days after receiving a tetanus vaccination. Erythrocyte sedimentation rate and C-reactive protein were elevated. Rheumatoid factor and human leukocyte antigen B-27 were negative. Her arthritis improved with the administration of nonsteroidal anti-inflammatory drugs. One week later the knee swelling and pain had settled. Reactive arthritis may occur after tetanus vaccination.  相似文献   
996.
The anatomical structure of the maxillary sinus is fundamental to maxillofacial surgery. The presence of septa, located at the inner surface of the maxillary sinus, increases the risk of sinus membrane perforation during sinus elevation for dental implant surgery. The aim of this study was to evaluate the anatomy of maxillary sinus septa.Data in this study was obtained from a total of 205 cases. One hundred and seventy‐seven patients were partially edentulous (PE) whereas 28 patients had no teeth. Dental computerized tomography (dental CT) was used in the assessment of 410 sinus segments (205 left and 205 right segments). The prevalence of sinus segments with septa was found to be 145/410. Septa were detected in 91 of the 177 PE cases. There were a total of 26 septa in 18 of the 28 completely edentulous (CE) cases. A total of 165 septa were detected in these segments. The prevalence of septa was 46.4% (26/56) in the CE, and 39.2% (139/354) in the PE segments. Thirty septa were found in the anterior, 110 in the middle and 25 in the posterior region. All detected septa were located mediolateral direction. Their relative position: lateral, middle or medial were also noted. The height measurements of the septa varied amongst the different positions. In view of the fact that septa of various heights and courses can develop in all parts of the maxillary sinus, timely and adequate assessment of the inner aspect of the maxillary sinus is essential to avoid complications during sinus augmentation procedures. Clin. Anat. 22:563–570, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
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The Early Glycoprotein IIb-IIIa inhibitors in Primary angioplasty (EGYPT) cooperation aimed at evaluating, by pooling individual patient’s data of randomized trials, the benefits of pharmacological facilitation with Gp IIb-IIIa inhibitors among STEMI patients undergoing primary angioplasty. In the current study we analyze the benefits of early Gp IIb-IIIa inhibitors in diabetic patients. The literature was scanned by formal searches of electronic databases (MEDLINE, EMBASE) from January 1990 to October 2007. We examined all randomized trials on facilitation by early administration of Gp IIb-IIIa inhibitors in STEMI. No language restrictions were enforced. Individual patients’ data were obtained from 11 out of 13 trials, including 1,662 patients. Diabetes was present in 281 (16.9%). Early Gp IIb-IIIa inhibitors were associated with improved preprocedural TIMI 3 flow (26.0% vs. 13.1%, P = 0.006), postprocedural TIMI 3 flow (90.1% vs. 75.0%, P = 0.18), MBG 3 (40.8% vs. 30.4%, P = 0.004), and less distal embolization (11.6% vs. 20.8%, P = 0.05). However, early Gp IIb-IIIa inhibitors did not significantly reduce mortality (8.3% vs. 9.5%, P = 0.64). This meta-analysis shows that pharmacological facilitation with early administration of Gp IIb-IIIa inhibitors in STEMI patients with diabetes undergoing primary angioplasty, is associated with significant benefits in terms of preprocedural and postprocedural TIMI flow, improved myocardial perfusion, without significant benefits in mortality.  相似文献   
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