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991.
In biological system, the interaction between nanoparticles (NPs) and serum biomolecules results in the formation of a dynamic corona of different affinities. The formed corona enriched with opsonin protein is recognized by macrophages and immune effector cells, resulting in rapid clearance with induced toxicity. Hence, to reduce corona genesis, surface-engineered ZnO (c-ZnO) NPs were in situ synthesized using a polyacrylamide-grafted guar gum (PAm-g-GG) polymer that provided surface neutrality to the NPs. Furthermore, we studied the characteristics of the corona formed onto uncapped anionic ZnO (bared ZnO [b-ZnO]) NPs and c-ZnO NPs by serum incubation. The result shows that b-ZnO NPs were wrapped with a high amount of serum proteins, particularly opsonin (IgG and complement), compared with c-ZnO NPs. These corona findings helped us substantially in interpretation of in vivo biokinetics studies. The in vivo study was accomplished by oral administration of NPs to Swiss mice at doses of 300 and 2000 mg/kg body weight. The studies performed on the cellular uptake, intracellular particle distribution, cytotoxicity, and pharmacokinetics of NPs indicated that b-ZnO NPs experienced higher immune cell recognition, hepatic inflammation, and resultant rapid clearance from the system, unlike c-ZnO NPs. Thus, capping of NPs by a neutral polymer has provided limited binding sites for undesired proteins around NPs, which limits immune system activation.  相似文献   
992.
993.
Interictal EEG and the Diagnosis of Epilepsy   总被引:4,自引:0,他引:4  
Summary:  The interictal EEG provides information that aids in diagnosis and management of epilepsy. One must remember that the EEG is merely a tool, and its usefulness depends largely upon the skill of the individual who wields it. Like all diagnostic tests, it has significant limitations and cannot substitute for a careful history and exercise of good judgment. Nonetheless, in skilled hands, it provides unique and vital information in many patients, and enhances our understanding of their condition.  相似文献   
994.
Considerable research has been conducted on the topic of entertainment-education (DD), the method of using entertainment platforms such as popular music, radio, and television programming to diffuse information, attitudes, and behaviors via role modeling. A significant portion of the recently published EE literature has used the example of the Radio Communication Project (RCP) in Nepal to demonstrate the effectiveness of EE and to argue that EE campaigns can indeed be participatory in nature. In this project, we apply the culture-centered approach to examine the discursive space created by the RCP and its claim of being participatory, A critical examination of RCP discourse brings forth an alternative lens for approaching RCP and its participatory claim.  相似文献   
995.
996.
Anomalous origin of aberrant right subclavian artery (ARSA) is a congenital anomaly where symptomatic patients require surgical intervention. It can be associated with other congenital anomalies. A 38-year-old, woman with a 4-year history of progressive dysphagia had bilateral cervical rib and a scalene node. She underwent surgical repair by right supraclavicular approach. She tolerated the procedure well, and was discharged home, symptom free, on postoperative day 4. This approach provides good exposure for simultaneous management of dysphagia lusoria and excision of cervical rib.  相似文献   
997.
998.
The Protein Data Bank is the most comprehensive source of experimental macromolecular structures. It can, however, be difficult at times to locate relevant structures with the Protein Data Bank search interface. This is particularly true when searching for complexes containing specific interactions between protein and ligand atoms. Moreover, searching within a family of proteins can be tedious. For example, one cannot search for some conserved residue as residue numbers vary across structures. We describe herein three databases, Protein Relational Database, Kinase Knowledge Base, and Matrix Metalloproteinase Knowledge Base, containing protein structures from the Protein Data Bank. In Protein Relational Database, atom–atom distances between protein and ligand have been precalculated allowing for millisecond retrieval based on atom identity and distance constraints. Ring centroids, centroid–centroid and centroid–atom distances and angles have also been included permitting queries for π-stacking interactions and other structural motifs involving rings. Other geometric features can be searched through the inclusion of residue pair and triplet distances. In Kinase Knowledge Base and Matrix Metalloproteinase Knowledge Base, the catalytic domains have been aligned into common residue numbering schemes. Thus, by searching across Protein Relational Database and Kinase Knowledge Base, one can easily retrieve structures wherein, for example, a ligand of interest is making contact with the gatekeeper residue.  相似文献   
999.
Curcumin is a polyphenol extracted from the rhizome of Curcuma longa and well known as a multi-functional drug with antioxidative, anti-cancerous and anti-inflammatory activities. Curcumin's antiageing and neuroprotective potential is widely reported. In the present study, effect of curcumin treatment dose 30 mg kg− 1 day− 1 was investigated against aluminium neurotoxicity in young and old animals. Direct and indirect intakes of aluminium have been reported to be involved in the etiology of several neurodegenerative disorders like Alzheimer's and Parkinson's diseases. Long term Al was administered through drinking water at a dose of 50 mg/kg/day for 6 months in both young (4 months) and old (18 months) male Wistar rats. Result obtained demonstrates that curcumin treatment attenuates the Al-induced alterations at biochemical, behavioral and ultrastructural levels which was well reflected in the electrophysiological recordings. Our results indicate that curcumin's ability to bind redox active metals and cross the blood-brain barrier could be playing crucial role in preventing against Al-induced neurotoxicity.  相似文献   
1000.
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