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961.
Coexisting bicuspid aortic and pulmonary valves is an extremely rare condition, and there have been few published cases. Diagnosis of bicuspid aortic valve is straightforward with 2D echocardiography; however, analysis of the morphology of the pulmonary valve is challenging. In this study, we report on a case of a 32‐year‐old man with bicuspid aortic and pulmonary valves diagnosed by 2D and 3D transthoracic echocardiography. The enlarged pulmonary artery without any obvious etiology led us to suspect a pulmonary valve anomaly; thus, we comprehensively evaluated it with 2D and 3D echocardiography, which confirmed the diagnosis of bicuspid pulmonary valve.  相似文献   
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Overexpression of PKD2 in the mouse is associated with renal tubulopathy.   总被引:1,自引:0,他引:1  
Polycystin-2 (PC-2), a cation channel of the Trp family, is involved in autosomal dominant polycystic kidney disease (ADPKD) type 2 (ADPKD2). This protein has recently been localized to the primary cilium where its channel function seems to be involved in a mechanosensory phenomenon. However, its biological function is not totally understood, especially in tubule formation. In the present paper, we describe a mouse model for human PC-2 overexpression, obtained by inserting a human bacterial artificial chromosome (BAC) containing the PKD2 gene. Three lines were generated, expressing different levels of PKD2. One line, PKD2-Y, has been explored in more detail and we will present physiological and molecular exploration of these transgenic animals. Our data demonstrate that transgenic animals older than 12 months present tubulopathy with proteinuria and failure to concentrate urine. Moreover, the kidney cortex has been found disorganized. Finally, we observe that extracellular matrix protein expression is downregulated in these animals. In conclusion, overexpression of human PKD2 leads to anomalies in tubular function, probably due to abnormalities in tubule morphogenesis.  相似文献   
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Neurovascular coupling, or the tight coupling between neuronal activity and regional cerebral blood flow (CBF), seems largely driven by the local processing of incoming afferent signals within the activated area. To test if cortical gamma-aminobutyric acid (GABA) interneurons-the local integrators of cortical activity-are involved in this coupling, we stimulated the basalocortical pathway in vivo, monitored cortical CBF, and identified the activated interneurons (c-Fos-immunopositive) and the neuromediators involved in this response. Basal forebrain (BF) stimulation induced ipsilateral increases in CBF and selective activation of layers II to VI somatostatin- and/or neuropeptide Y-containing, as well as layer I GABA interneurons. Nitric oxide synthase interneurons displayed weak bilateral activation, whereas vasoactive intestinal polypeptide- or acetylcholine (ACh)-containing GABA interneurons were not activated. Selective cholinergic deafferentation indicated that ACh released from stimulated BF afferents triggered the CBF response, but the latter was mediated, in part, by the local release of GABA from cholinoceptive cortical interneurons, and through GABA-A receptor-mediated transmission. These data show that activation of specific subsets of GABA interneurons and their GABA-A-mediated effects on neuronal, vascular, and/or astroglial targets are necessary for the full expression of the hemodynamic response to BF stimulation. Further, these findings highlight the importance of understanding the cellular networks and circuitry that underlie hemodynamic signals, as only specific subsets of neurons may be activated by a given stimulus, depending on the afferent inputs they receive and integrate.  相似文献   
968.
Ohne ZusammenfassungAus Gründen der Raumersparnis verzichten wir auf die Darlegung der in ihren Resultaten durchaus noch nicht übereinstimmenden Literatur. Sie findet sich in der Dissertation von E. HAHNE, Rostock 1023.  相似文献   
969.
Venous thromboembolism (VTE) is an important medical problem that affects millions of patients each year. With appropriate prophylaxis, many of these thromboembolic events can be prevented. Although strong evidence supporting VTE prophylaxis spans several decades, several large American and global registries have documented very poor use of appropriate prophylaxis. Because of increasing regulatory requirements, hospitals nationwide are in the process of developing documentation of appropriate VTE prophylaxis programs for both surgical and medical patients. A wide range of clinicians must understand what constitutes appropriate VTE prophylaxis in various patient populations. With the existence of numerous pharmacologic agents, abundance of data from major clinical trials, and several nationally recognized clinical guidelines, compiling the needed reference material to make evidence-based decisions on appropriate VTE prophylaxis can be difficult for clinicians. Therefore, we provide a bibliography of key articles and guidelines related to the prevention of VTE in various patient groups. We hope this compilation will serve as a resource for pharmacists, physicians, nurses, residents, and students responsible for the care of patients who may be at risk for VTE.  相似文献   
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