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181.
Congenital sinus of Valsalva aneurysms are extremely rare in Spain. The lesion consists of a defect that allows the aortic media to separate from the annulus fibrosus of the aortic valve, causing it to dilate with arterial pressure. The natural course of the aneurysm involves the risk of complication due to bacterial endocarditis, with conduction blocks or myocardial ischemia. Rupture of the aneurysm, usually into a right chamber, causes a left-right shunt that leads to heart failure and death if untreated. We present the case of a previously asymptomatic 60-year-old woman who presented with a clinical picture that led to a diagnosis of hyperthyroidism, and in whom there occurred a coincident rupture of a congenital sinus of Valsalva aneurysm. We describe the anesthetic procedure and emphasize the importance of intraoperative echocardiography throughout the resection of the aneurysm.  相似文献   
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A cross-sectional study was carried out to determine the prevalence of Streptococcus mutans and Streptococcus sobrinus and the association of the two in a random sample (n=614) of the child population of the region of Valencia (Spain). Saliva samples were analyzed by the quantitative polymerase chain reaction (PCR) method to study the relation of these bacteria to caries prevalence and the DMFT index. The prevalence of S. mutans was 35.4% at age 12 and 22.9% at age 15, that of S. sobrinus 18.9% and 8.4% and that of the S. mutans-S. sobrinus association 18.2% and 6.8% respectively. At both 12 and 15 years of age, the caries prevalence rates were lower in the Streptococcus-free group of children (37.6% and 48.5% respectively) and higher in the S.mutans-only group (67.3% and 74.0%). At the age of 12, the DMFT index was significantly higher in the mutans-only carriers (2.1) than in the Streptococcus-free and S. mutans-S. sobrinus association groups (both 0.9). At the age of 15, the DMFT index was significantly higher in the S. mutans-S. sobrinus association (3.71) and mutans-only (3.1) carrier groups than in the Streptococcus-free group (1.4). Determination of S. mutans and S. sobrinus by real-time quantitative PCR can provide valuable information for caries risk assessment in epidemiological studies. Key words:Streptococcus mutans, Streptococcus sobrinus, polymerase chain reaction, dental caries, cross-sectional studies.  相似文献   
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Intramedullary neurenteric cysts (NEC) without associated malformations are extremely rare and, to our knowledge, have never been reported in association with calcification. We report a unique imaging presentation as a partially calcified mass of an isolated intramedullary neuroenteric cyst of the lower thoracic spinal cord with pathologic correlation. The literature for isolated forms of intramedullary NEC since the advent of magnetic resonance imaging is also reviewed.  相似文献   
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Caveolin‐1 (CAV1) has been implicated in the regulation of several signaling pathways and in oncogenesis. Previously, we identified CAV1 as a key determinant of the oncogenic phenotype and tumorigenic activity of cells from tumors of the Ewing's Sarcoma Family (ESFT). However, the possible CAV1 involvement in the chemotherapy resistance commonly presented by an ESFT subset has not been established to date. This report shows that CAV1 expression determines the sensitivity of ESFT cells to clinically relevant chemotherapeutic agents. Analyses of endogenous CAV1 levels in several ESFT cells and ectopic CAV1 expression into ESFT cells expressing low endogenous CAV1 showed that the higher the CAV1 levels, the greater their resistance to drug treatment. Moreover, results from antisense‐ and shRNA‐mediated gene expression knockdown and protein re‐expression experiments demonstrated that CAV1 increases the resistance of ESFT cells to doxorubicin (Dox)‐ and cisplatin (Cp)‐induced apoptosis by a mechanism involving the activating phosphorylation of PKCα. CAV1 knockdown in ESFT cells led to decreased phospho(Thr638)‐PKCα levels and a concomitant sensitization to apoptosis, which were reversed by CAV1 re‐expression. These results were recapitulated by PKCα knockdown and re‐expression in ESFT cells in which CAV1 was previously knocked down, thus demonstrating that phospho(Thr638)‐PKCα acts downstream of CAV1 to determine the sensitivity of ESFT cells to chemotherapeutic drugs. These data, along with the finding that CAV1 and phospho(Thr638)‐PKCα are co‐expressed in ∼45% of ESFT specimens tested, imply that targeting CAV1 and/or PKCα may allow the development of new molecular therapeutic strategies to improve the treatment outcome for patients with ESFT.  相似文献   
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As a part of a research program directed to the discovery of novel antidepressant agents, a series of new hetero[2,1]benzothiazepine derivatives was synthesized. Some of these compounds antagonized the ptosis and motor depression induced by tetrabenazine and were also active in the Porsolt forced swimming test.  相似文献   
190.
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