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41.
The present study was undertaken to evaluate effects of quercetin, a major dietary flavonoid occurring in foods of plant origin, on cell viability and migration of osteoblastic cells. Quercetin inhibited cell viability, which was largely attributed to apoptosis, in a dose-and time-dependent manner in osteoblastic cells. Similar cytotoxicity of quercetin was observed in adipose tissue-derived stromal cells. Quercetin exerted a protective effect against H2O2-induced cell death, whereas it increased TNF-α-induced cell death. Western blot analysis showed that quercetin induced activation of ERK and p38, but not JNK. Quercetin-induced cell death was prevented by the ERK inhibitor PD98059, but not by inhibitors of p38 and JNK. Quercetin increased Bax expression and caused depolarization of mitochondrial membrane potential, which were inhibited by PD98059. Quercetin induced caspase-3 activation, and the quercetininduced cell death was prevented by caspase inhibitors. Quercetin inhibited cell migration, and its effect was prevented by inhibitors of ERK and p38. Taken together, these findings suggest that quercetin induces apoptosis through a mitochondria-dependent mechanism involving ERK activation and inhibits migration through activation of ERK and p38 pathways. Quercetin may exert both protective and deleterious effects in bone repair.  相似文献   
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Schwannomas are particularly rare neoplasms among tumors of the retroperitoneal space. Only 0.3-3.2% of benign schwannomas are found in retroperitoneal locations. As these tumors are usually asymptomatic and discovered by chance or in the course of the evaluation of an unrelated health problem, they may cause the delay of early diagnosis and treatment. With recent advances in the field of minimally invasive surgery, several laparoscopic approaches to retroperitoneal schwannomas have been reported. In this paper, we present the case of a 59-year-old female patient with an asymptomatic retroperitoneal mass that was found during a regular medical checkup. The mass was located between the inferior vena cava (IVC) and aorta under the pancreaticoduodenal unit (site of lymph node 16b1), compressing the IVC. She underwent successful laparoscopic surgery for retroperitoneal schwannoma. In addition, we summarized the literature on cases regarding the laparoscopic management of the retroperitoneal schwannoma.  相似文献   
44.
The authors used vertebroplasty for the treatment of severe lower lumbar radicular pain caused by osteoporotic compression fracture. Patients presented with severe radiating leg pain rather than lower back pain from recent osteoporotic compression fracture of lower lumbar vertebra. Radiologic findings showed osteoporotic compression fracture combined with preexisting stenosis of the intervertebral foramen resulting in root compression. After injection of polymethylmethacrylate into the compressed vertebral body through the pedicle of the symptomatic side, all seven patients experienced dramatic pain relief that lasted throughout the mean follow-up duration of 9.1 months. They conclude that vertebroplasty may be an effective way of relieving radicular pain caused by osteoporotic compression fracture combined with foraminal stenosis.  相似文献   
45.
Fifteen skeletally immature patients with double major adolescent idiopathic scoliosis with large lumbar curves and notable L4 and L5 coronal plane obliquity were retrospectively studied. Seven patients who underwent anterior release and fusion of the lumbar curve with segmental anterior instrumentation and subsequent posterior instrumentation ending at L3 were compared with eight patients treated with anterior release and fusion without anterior instrumentation followed by posterior instrumentation to L3 or L4. At 4.5 years follow-up (range 2.5-7 years), curve correction, coronal balance and fusion rate were not statistically different between the two groups; however, the group with anterior instrumentation had improved coronal plane, near normalangulation in the distal unfused segment compared with the group without anterior instrumentation. In cases involving severe lumbar curvatures in the context of double major scoliosis, when as a first stage anterior release is chosen, the addition of instrumentation appears to restore normal coronal alignment of the distal unfused lumbar segment, and may in certain cases save a level compared with traditional fusions to L4.  相似文献   
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RATIONALE AND OBJECTIVES: The purpose of this study in rabbits was to evaluate the effect of furosemide on resistive index (RI) in the diagnosis of partial hydronephrosis. MATERIALS AND METHODS: In 14 rabbits the left ureter was ligated by being tied to an angiographic guide wire. Doppler sonography was performed before and 1 and 6 hours, 1 and 3 days, and 1, 2, and 4 weeks after ureteral ligation. At each interval it was performed both before and after intravenous injection of saline and furosemide. RIs were compared (a) between obstructed and contralateral kidneys and (b) before and after furosemide administration, and the statistical significance of any differences was determined. RESULTS: Obstructed kidneys had significantly higher RIs than the contralateral kidneys before furosemide administration at five of seven postligation measurements and after furosemide administration at all seven. The differences between obstructed and contralateral kidneys were significantly higher after furosemide administration (P < .05). The increase in RI after furosemide administration was significantly greater in obstructed than in contralateral kidneys (P < .05). CONCLUSION: The results in a rabbit model indicate that Doppler sonography with furosemide administration is a valuable method for evaluating hydronephrosis. The administration of furosemide accentuates the difference in RI between obstructed and nonobstructed kidneys.  相似文献   
48.
We present a case of cerebellopontine (CP) angle ganglioglioma in a young child with developmental delay and no trigeminal nerve symptoms. MR imaging demonstrated a mass of homogeneous low signal intensity in the left CP angle on T1-weighted images with no enhancement with gadolinium, and of relatively homogeneous high signal intensity on T2-weighted images.  相似文献   
49.
Echocardiography and catheterization angiography suffer certain limitations in the evaluation of congenital heart diseases in adults, though these are overcome by MRI, in which a wide field-of view, unlimited multiplanar imaging capability and three-dimensional contrast-enhanced MR angiography techniques are used. In adults, recently introduced fast imaging techniques provide cardiac MR images of sufficient quality and with less artifacts. Ventricular volume, ejection fraction, and vascular flow measurements, including pressure gradients and pulmonary-to-systemic flow ratio, can be calculated or obtained using fast cine MRI, phase-contrast MR flow-velocity mapping, and semiautomatic analysis software. MRI is superior to echocardiography in diagnosing partial anomalous pulmonary venous connection, unroofed coronary sinus, anomalies of the pulmonary arteries, aorta and systemic veins, complex heart diseases, and postsurgical sequelae. Biventricular function is reliably evaluated with cine MRI after repair of te ralogy of Fallot, and Senning''s and Mustard''s operations. MRI has an important and growing role in the morphologic and functional assessment of congenital heart diseases in adolescents and adults.  相似文献   
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