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Background  

It has been asserted that the success rate of oral appliances was more satisfactory for mild to moderate obstructive sleep apnea (OSA) than severe ones; besides, there is a lack of literature about mandibular advancement device (MAD) application for edentulous patients with OSA.  相似文献   
83.

Background

Pulmonary hypertension (PH) caused by chronic obstructive lung disease (COLD) essentially involves the right heart. Also left ventricular (LV) systolic and diastolic functions may be affected.

Objectives

The aim of this study was to investigate the effect of on LV diastolic function in patients with COLD.

Methods

A total of 47 patients with COLD and 20 controls were included in this study. All patients underwent Doppler echocardiography, tissue Doppler imaging examinations and right cardiac catheterization. The patients were divided into 2 subgroups according to mean pulmonary arterial pressure (mPAP): patients without PH (group1, n = 25) and with PH (group 2, n = 22). The following measurements were taken: peak velocity of early diastolic filling (E), peak late filling with atrial contraction (A), E/A ratio, deceleration time (DT) of E, isovolumic relaxation time (IVRT), early (Em) and late (Am) diastolic mitral lateral annulus velocity.

Results

Mitral E/A < 1 and Em < 8 cm/sec were higher in group 2 than in group 1 and the control group. There were significant correlations between mPAP and both mitral E/A (r:? 0.60) and Em (r:? 0.45). In multivariate model, mPAP was not found to be significant on mitral E/A ratio < 1, but there was a significant effect on mitral Em < 8 cm/sec (odds ratio [OR]:1.14, P < 0.05).

Conclusion

This study shows that LV diastolic dysfunction in COLD is closely correlated to PH levels. Although increased mPAP may affect the mitral E/A ratio, it seems to have no effect on mitral E/A < 1, whereas it has an independent effect on Em < 8 cm/sec. Copyright © 2010 Wiley Periodicals, Inc.
  相似文献   
84.

Introduction  

Renal physiology is a partially cyclooxygenase (COX)-dependent system. Kidneys express both COX-1 and COX-2 enzymes. In this study, we tried to investigate the effects of diclofenac sodium (D), with or without furosemide (F), on plasma renin activity (PRA), serum and urine electrolytes, creatinine clearance, and COX-1 and COX-2 expression in the renal cortex.  相似文献   
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OBJECTIVE: Phase-contrast X-ray computed tomography (PCCT) with an interferometer can reveal the inner soft tissue structures of biological objects without contrast agent, and the image quality is thought to resemble that of magnetic resonance imaging (MRI). Comparative study among PCCT, MRI, and optical microscopy was undertaken. METHODS: Three formalin-fixed colon cancer specimens from nude mice were imaged both by PCCT with a reconstructed volumetric resolution of (0.018)3 mm3 and 4.74-T MRI with that of (0.075)3 mm3. RESULTS: Phase-contrast X-ray computed tomography with an interferometer clearly demonstrated the inner structures of colon cancer masses, such as cancer, necrosis, surrounding tumor vessels, and skin, in a similar way to low-magnified optical microscopic images and had approximately 4.0-fold higher signal-to-noise ratio than MRI. CONCLUSIONS: With formalin-fixed biological samples, PCCT exhibited higher image quality than MRI and was thought to be suitable for detailed imaging of soft tissue with high volumetric resolution.  相似文献   
90.
Cauda equina syndrome is the result of any lesion that compresses or paralyzes cauda equina roots which are both motor and sensory. It is an uncommon syndrome, which features low back pain, sciatica, variable lower extremity motor and sensory loss with possible bladder and bowel dysfunction. It is an emergency situation as it may cause significant morbidity such as permanent paralysis, impaired bladder and/or bowel control or loss of sexual sensation. We present the case of a patient who was admitted to the emergency department with a traumatic posterior L5-S1 dislocation, low back pain and bladder dysfunction 8 days following an initial trauma. Open L5-S1 reduction and posterior stabilization was performed and the dural sac was decompressed. Most of the patient's neurological deficits resolved over several years, following the initial surgery.  相似文献   
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