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排序方式: 共有991条查询结果,搜索用时 31 毫秒
61.
Ali N Yoshizumi M Fujita Y Izawa Y Kanematsu Y Ishizawa K Tsuchiya K Yano S Sone S Tamaki T 《Journal of pharmacological sciences》2005,98(2):130-141
Vascular endothelial growth factor (VEGF) was reported to be a potent proangiogenic factor that plays a pivotal role in both physiological and pathological angiogenesis. M475271, 4-quinazolinamine, N-(2-chloro-5-methoxyphenyl)-6-methoxy-7-[(1-methyl-4-piperidinyl) methoxy]-(9Cl), is a new anilinoquinazoline derivative that showed selective inhibition of Src kinase activity and tumor growth in vivo. Here, we examined the effect of M475271 on VEGF-induced human umbilical vein endothelial cell (HUVEC) proliferation and migration and their intracellular mechanisms. Our findings showed that M475271 pretreatment resulted in a significant inhibition of VEGF-induced HUVEC proliferation, [(3)H]thymidine incorporation, and migration. M475271 inhibited VEGF-induced Flk-1 and Src phosphorylation and their association. Confocal laser microscopic examination confirmed the inhibitory effect of M475271 on VEGF-induced Flk-1/Src association. M475271 inhibited VEGF-induced extracellular signal-regulated kinase1/2 (ERK1/2) and p38 but not Akt activation in a concentration-dependent manner. M475271, PI3-K inhibitor, and p38 inhibitor inhibited VEGF-induced HUVEC proliferation and migration. However, a MEK1/2 inhibitor inhibited VEGF-induced proliferation but not migration. These findings suggest that M475271 attenuates VEGF-induced HUVEC proliferation and migration through the inhibition of signaling pathways involving Src, ERK1/2, and/or p38. Taken together, these data indicate that M475271 may be a useful candidate for inhibition of endothelial cell proliferation and migration relevant to angiogenesis. 相似文献
62.
63.
Ojanguren A Doenz F Qanadli SD Madoff DC Halkic N Bessoud B Denys A 《Journal of vascular and interventional radiology : JVIR》2005,16(7):1033-1036
Retained T-tubes are rare complications after biliary surgery. The authors present three cases of retained T-tubes in patients with transplanted liver that could not be removed by a standard manual traction. The authors describe a new simple percutaneous method that allows removal of these T-tubes without complication. 相似文献
64.
Denys A Lacombe C Schneider F Madoff DC Doenz F Qanadli SD Halkic N Sauvanet A Vilgrain V Schnyder P 《Journal of vascular and interventional radiology : JVIR》2005,16(12):1667-1674
PURPOSE: To describe the safety, complications, and liver regeneration associated with the left liver after embolization of the right portal vein (PV) in patients with hepatocellular carcinoma (HCC) developed in the setting of advanced liver fibrosis and cirrhosis. MATERIALS AND METHODS: Forty patients (31 men, nine women; mean age, 62 years) with HCC underwent PV embolization over a 4-year period. Embolization was performed from a left PV percutaneous access with use of n-butyl cyanoacrylate (NBCA) mixed with iodized oil. Computed tomography (CT) volumetry was performed before and 1 month after PV embolization to measure the left lobe volume as well as the functional liver ratio defined by the ratio between the left lobe and the total liver volume minus tumoral volume. PV pressure and liver enzyme levels were compared before and 1 month after the procedure and complications were registered. Factors potentially affecting regeneration (age, sex, diabetes, chemoembolization, functional liver ratio before PV embolization, and Knodell histologic score) were evaluated by one-way and stepwise regression analysis. RESULTS: PV embolization could be achieved successfully in all cases. Two patients had partial PV thrombosis on the 1-month follow-up CT and two patients developed transient ascites after PV embolization. The left lobe volume increase was 41% +/- 32% after PV embolization and the functional liver ratio increased from 28% +/- 10% to 36% +/- 10% (P < .0001). Hypertrophy of the left lobe was greater in patients with a low functional liver ratio before PV embolization and those with an F3 fibrosis score. Other factors had no influence on left lobe regeneration. CONCLUSION: PV embolization with use of NBCA is feasible in patients with advanced fibrosis and cirrhosis. Hypertrophy of the left lobe of the liver after PV embolization has a statistically significant correlation with lower functional liver ratio and lower degrees of fibrosis. 相似文献
65.
Hypercalcemia is a frequent finding in clinical practice. All possible causes must be considered in a patient with hypercalcemia. The association between both benign or malignant thyroid disease and primary hyperparathyroidism is well recognized. Up to 65% with primary hyperparathyroidism have associated thyroid abnormality. Hypercalcemia has also been associated with many malignant conditions. But, it is rarely seen in digestive tract cancer, such as carcinoma of gallbladder. Hypercalcemia syndrome is an absolutely rare entity. It is coexisting with hyperthyroidism, primary hyperparathyroidism and cancer of the gallbladder. 相似文献
66.
Aslan A Vatansever HS Aslan GG Eskiizmir G Giray G 《The Journal of laryngology and otology》2005,119(8):600-605
The effect of thermal energy due to drilling around the facial nerve canal on the facial nerve was histopathologically evaluated in four guinea pigs. The bony canal of the facial nerve was drilled using a 3 mm diamond burr for one minute. The temperature changes on the facial nerve canal were noted before and after dissection. The temporal bones of the animals were histopathologically examined under light microscopy using haematoxylin & eosin (H&E) and solochrome cyanine staining for myelin, and immunohistochemical staining for neuronal nitric oxide synthase (nNOS). Compared to the control group, it was observed with H&E staining that there was oedema among the axonal fibres and with solochrome cyanine staining that the thickness of the myelin fibres was decreased, and that the severity and extent of nNOS activity was decreased in the axonal fibres. It was concluded that a temperature increase on the facial canal may potentially lead to inflammation of the nerve, and may also cause deterioration of nerve conduction to some extent. 相似文献
67.
Tuncel D Yücesan C Erden E Savaş A Erden I Mutluer N 《Clinical neurology and neurosurgery》2005,107(3):249-252
Idiopathic hypertrophic cranial pachymeningitis (IHCP) consists of meningeal thickening due to chronic inflammation for which no cause such as infection, specific granulomatous disease, or malignancy is demonstrable. We present a case of IHCP with perifocal brain edema suggesting mass lesion with its magnetic resonance imaging (MRI) and pathologic findings. A 36-year-old woman was admitted to our hospital in August 2001 with a complaint of motor weakness in her left leg for 1 month. Magnetic resonance imaging with gadolinium revealed enhancement of the thickened dura mater and perifocal edema in the right frontoparietal region suggesting a mass lesion. Histological examination of the biopsy specimen revealed a dense fibrous cellular tissue. There was no obvious inflammatory infiltrate but in some areas between fibrous bundles one or two lymphocytes were detected. According to our knowledge, our patient is the second report in the literature of IHCP with focal edema causing a mass effect. 相似文献
68.
The aim of this report is to describe a case presenting with complaints of orbital pain, altered facial sensation, nasal obstruction and unilateral spontaneous nose bleeding. Panoramic radiography and computerized tomography disclosed a large pedunculated heterogeneous mineral opacity with two impacted molar teeth invading the maxillary sinus. The patient was operated on under general anaesthesia. Microscopic examination of the surgical specimen revealed relatively dense, compact bone with sparse marrow tissue that was diagnosed as osteoma. Clinical characteristics and biological behaviour of this lesion were evaluated with special regard to the reliability of imaging modalities and surgical procedures. 相似文献
69.
Biochemical bone markers in nephrotic children 总被引:1,自引:0,他引:1
In this study we evaluated the effects of high-dose corticosteroid (CS) therapy and the character of the nephrotic syndrome (NS) itself on bones in patients with normal glomerular filtration rate. We measured serum osteocalcin (OC), alkaline phosphatase (ALP), intact parathyroid hormone (iPTH), 25-hydroxyvitamin D, calcium (Ca), phosphorus (P), and magnesium (Mg) levels, and urinary Ca and protein excretion in nephrotic children during the active phase before (group Ia) and after CS treatment (group Ib). The results were compared with age-matched control subjects. A significant increase in urinary Ca excretion was observed after CS treatment. Serum ALP, OC, and iPTH levels were within normal limits at the time of study entry. However, both serum OC and ALP levels showed a significant decrease after the completion of CS treatment (OC from 13.6±9.2 ng/ml to 6.7±5.2 ng/ml and ALP from 151.8±60.2 U/l to 116±43.8 U/l). 25-Hydroxyvitamin D levels increased to 17.2±8.9 g/l from 9.9±6.9 g/l after CS treatment. The effects of recurrent use of CSs were assessed by dividing nephrotic patients into two subgroups: infrequent relapsers (IFR) and frequent relapsers (FR). The cumulative dose of CS was 28,125 mg/m2 for IFR and 105,000 mg/m2 for FR. The changes in OC, ALP, and 25-hydroxyvitamin D levels after CS treatment were significantly different between IFR and FR. We conclude that high-dose CS treatment causes a decrease in bone formation, as shown by the changes in OC and ALP levels. 25-Hydroxyvitamin D levels remained lower than control subjects after CS therapy. The higher the cumulative dose of CS used the more marked the changes in biochemical bone markers. The contribution of FR to baseline 25-hydroxyvitamin D levels needs further study. 相似文献
70.
Yelmen KN 《The Tohoku journal of experimental medicine》2004,203(3):219-232
Acute hypoxia produces an increase in ventilation. When the hypoxia is sustained, the initial increase in ventilation is followed by a decrease in ventilation. Hypoxia causes changes in brain neurotransmitters depending on its severity and durations. The purpose of this study was to investigate the role of gamma-aminobutyric acid (GABA) and glutamate for hypoxic ventilatory response in rabbits. The experiments were performed in peripheral chemoreceptors intact and denervated rabbits anesthetized with Na-pentobarbitate. For intracerebroventricular (ICV) injections of reagents in each animal, cannula was placed in left lateral cerebral ventricle by stereotaxic method. After ICV injection of GABA (0.48 mg/kg), air breathing in both groups caused a depression of respiratory activity. On the other hand, after ICV injection of GABA, breathing of hypoxic gas mixture (8% O(2)-92% N(2)) in both groups produced the hypoxic hyperventilation. After ICV injection of GABA, blockade of GABA(A) receptors with bicuculline (0.2 mg/kg) did not prevent the hypoxic hyperventilation. In contrast, after ICV GABA injection, blockade of glutamate NMDA receptors with MK-801 (0.09 mg/kg) completely abolished the hypoxic hyperventilation observed while the animals were breathing hypoxic gas mixture. Our findings suggest that ICV injection of GABA causes respiratory depression in normoxic conditions, and that it increases ventilation in hypoxic conditions with or without peripheral chemoreceptor impulses by increasing glutamate. 相似文献