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91.
Many patients suffer from mild, moderate or severe pain during or after root canal therapy. The purpose of this study was to evaluate the efficacy of supraperiosteal injection of dexamethasone into the periapical tissues to prevent postoperative pain associated with inflammation. In a double-blind, placebo-controlled clinical trial, 100 patients with moderate or severe pain who were referred to dental school of Tehran Islamic Azad University participated in this study. All patients had a tooth with clinical diagnosis of irreversible pulpitis. After administration of local anaesthesia, access cavity was prepared. Then, the root canals were instrumented to a minimum of a No. 25 K-file. One millilitre dexamethasone (8 mg 2 mL(-1)) or placebo was injected around the tooth. The severity of pain was assessed with regard to a modified visual analogue scale after 6, 12, 24 and 48 h. The data was analysed statistically with chi-square test. Dexamethasone was considerably effective on controlling the severity of pain during the first 24 h; in contrast, there was no difference between dexamethasone and placebo groups 48 h after the first appointment. A single dose of dexamethasone infiltrated around the apex of a tooth with irreversible pulpitis could be effective in reduction or prevention of postoperative endodontic pain during the first 24 h.  相似文献   
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Laugier-Hunziker syndrome is a rare mucocutaneous pigmentary disorder. It is considered benign, but other mucocutaneous pigmentation disorders are in the differential diagnosis and should be ruled out. This report describes a woman with pigmentation of the labial mucosa of the lower lip who was successfully treated with a Q-switched 532-nm laser.  相似文献   
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The sensitivity of shear stress over smooth muscle cells (SMCs) to the deformability of media layer due to pressure is investigated in thoracic aorta wall using three-dimensional simulations. A biphasic, anisotropic model assuming the radius, thickness, and hydraulic conductivity of vessel wall as functions of transmural pressure is employed in numerical simulations. The leakage of interstitial fluid from intima to media layer is only possible through fenestral pores on the internal elastic lamina (IEL). The media layer is assumed a heterogeneous medium containing SMCs embedded in a porous extracellular matrix of elastin, proteoglycan, and collagen fibers. The applicable pressures for the deformation of media layer are varied from 0 to 180 mmHg. The SMCs are cylindrical objects of circular cross section at zero pressure. The cross sectional shape of SMCs changes from circle to ellipse as the media is compressed. The local shear stress over the nearest SMC to the IEL profoundly depends on pressure, SMCs configurations, and the corresponding distance to the IEL. The consideration of various SMC configurations, namely the staggered and square arrays, mimics various physiological conditions that can happen in positioning of an SMC. The results of our simulations show that even the second nearest SMCs to the IEL can significantly change their functions due to high shear stress levels. This is in contrast to earlier studies suggesting the highest vulnerability to shear stress for the innermost layer of SMCs at the intimal-medial interface.  相似文献   
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Background

Adenosine stress cardiovascular magnetic resonance (CMR) has been proven an effective tool in detection of reversible ischemia. Limited evidence is available regarding its accuracy in the setting of acute coronary syndromes, particularly in evaluating the significance of non-culprit vessel ischaemia. Adenosine stress CMR and recent advances in semi-quantitative image analysis may prove effective in this area. We sought to determine the diagnostic accuracy of semi-quantitative versus visual assessment of adenosine stress CMR in detecting ischemia in non-culprit territory vessels early after primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI).

Methods

Patients were prospectively enrolled in a CMR imaging protocol with rest and adenosine stress perfusion, viability and cardiac functional assessment 3 days after successful primary-PCI for STEMI. Three short axis slices each divided into 6 segments on first pass adenosine perfusion were visually and semi-quantitatively analysed. Diagnostic accuracy of both methods was compared with non-culprit territory vessels utilising quantitative coronary angiography (QCA) with significant stenosis defined as ≥70%.

Results

Fifty patients (age 59 ± 12 years) admitted with STEMI were evaluated. All subjects tolerated the adenosine stress CMR imaging protocol with no significant complications. The cohort consisted of 41% anterior and 59% non anterior infarctions. There were a total of 100 non-culprit territory vessels, identified on QCA. The diagnostic accuracy of semi-quantitative analysis was 96% with sensitivity of 99%, specificity of 67%, positive predictive value (PPV) of 97% and negative predictive value (NPV) of 86%. Visual analysis had a diagnostic accuracy of 93% with sensitivity of 96%, specificity of 50%, PPV of 97% and NPV of 43%.

Conclusion

Adenosine stress CMR allows accurate detection of non-culprit territory stenosis in patients successfully treated with primary-PCI post STEMI. Semi-quantitative analysis may be required for improved accuracy. Larger studies are however required to demonstrate that early detection of non-culprit vessel ischemia in the post STEMI setting provides a meaningful test to guide clinical decision making and ultimately improved patient outcomes.  相似文献   
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Amebiasis presenting as acute appendicitis is extremely rare. The case of a 38-year-old Hispanic man who presented to the hospital with symptoms and signs suggestive of acute appendicitis is reported. He underwent laparoscopic appendectomy and the pathologic examination of the appendix revealed multiple trophozoites of Entamoeba histolytica. The patient was treated postoperatively with metronidazole for amebiasis, and follow-up stool studies showed no sign of residual infection. The patient has remained asymptomatic.  相似文献   
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In this study, the shape and the configuration of smooth muscle cells (SMCs) within the arterial wall are altered to investigate their influence on molecular transport across the media layer of the thoracic aorta wall. In a 2D geometry of the media layer containing SMCs, the finite-element method has been employed to simulate the diffusion of solutes through the media layer. The media is modeled as a heterogeneous system composed of SMCs having elliptic or circular cross sections embedded in a homogeneous porous medium made of proteoglycan and collagen fibers with an interstitial fluid filling the void. The arrangement of SMCs is in either ordered or disordered fashion for different volume fractions of SMCs. The interstitial fluid enters the media through fenestral pores, which are assumed to be distributed uniformly over the internal elastic lamina (IEL). Results revealed that in an ordered arrangement of SMCs, the concentration of adenosine 5′-triphosphate (ATP) over the surface of SMCs with an elliptic cross section is 5–8% more than those of circular SMCs in volume fractions of 0.4–0.7. The ATP concentration at the SMC surface decreases with volume fraction in the ordered configuration of SMCs. In a disordered configuration, the local ATP concentration at the SMC surface and in the bulk are strongly dependent on the distance between neighboring SMCs, as well as the minimum distance between SMCs and fenestral pores. Moreover, the SMCs in farther distances from the IEL are as important as those just beneath the IEL in disordered configurations. The results of this study lead us to better understanding of the role of SMCs in controlling the diffusion of important species such as ATP within the arterial wall.  相似文献   
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