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Context: Scorzonera L. species (Asteraceae) are edible and as medicinal plants are used for various purposed in folk medicine.

Objective: The methanol extracts of the aerial parts and roots from 27 Scorzonera taxa were investigated for their possible neurobiological effects.

Materials and methods: Inhibitory potential of the Scorzonera species was tested against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and tyrosinase (TYRO) at 100?µg?mL?1 using ELISA microtiter assay. Antioxidant activity of the extracts was tested with radical scavenging activity, metal-chelation capacity, ferric- (FRAP), and phosphomolibdenum-reducing antioxidant power (PRAP) assays. Chlorogenic acid, hyperoside, rutin, and scorzotomentosin-4-O-β-glucoside were also screened in the same manner. Total phenol and flavonoid quantification in the extracts were determined spectrophotometrically.

Results: The aerial parts of Scorzonera pisidica (40.25?±?0.74%) and chlorogenic acid (46.97?±?0.82%) displayed the highest TYRO inhibition, while the remaining samples showed only trivial inhibition against cholinesterases (2.08?±?1.35%–25.32?±?1.37%). The same extract of S. pisidica was revealed to be the most potent in scavenging of all three radicals and FRAP assay.

Discussion and conclusion: Out of 27 taxa, S. pisidica, in particular, may deserve further investigation for its neuroprotective potential.  相似文献   
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Anomalous right coronary artery is a rare entity with an incidence of 0.26%. The anomalous origin usually arises from the left sinus valsalva. An anomalous right coronary artery arising from the left anterior descending artery is rare. It is usually known as a benign entity but may have clinical importance due to its course between the aorta and pulmonary artery which may cause myocardial ischemia or sudden cardiac death. Here we present an anomalous coronary artery arising from the left anterior descending artery detected by coronary artery angiogram and confirmed by multislice computed tomography thereafter. 40% retrospective electrocardiographic gating is performed and volume-rendered 3 D and axial MIP (maximum intensity projection) images were reconstructed on a Vitrea post- processing Workstation. The images demonstrated the anomalous origin of the right coronary artery arising from the proximal portion of left anterior descending artery after the first septal perforator and coursing.  相似文献   
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Congenital, infectious, toxic, and demyelinating disorders are common etiological causes of deafness. Tuberculous meningitis, as one of the infectious causes, should be considered in the differential diagnosis since tuberculosis represents an endemic public health problem in developing countries. Multiple cranial nerve palsies can be expected due to basal meningitis; however, presentation with bilateral hearing loss is quite rare. Early diagnosis and treatment are crucial to prevent mortality and residual neurologic deficits. The focus of this discussion is a 42-year-old female presenting with bilateral hearing loss and nonspecific complaints who was finally diagnosed with chronic tuberculous meningitis. We also demonstrate the characteristic radiological and histopathological findings.Congenital, infectious, toxic, vascular, tumoral, and demyelinating disorders are common etiologic factors that can result in deafness. Acoustic trauma, endolymphatic hydrops, and senility are relatively rare causes that should also be taken into account. Bilateral hearing loss is an unusual clinical presentation, resulting from any one of these conditions. Among the infectious causes, tuberculosis still represents an endemic public health problem in developing countries and tuberculous meningitis, which is the most common form of CNS involvement, accounts for 1-2% of these cases.1 Sufferers generally describe constitutional symptoms including fever and night sweats or various complaints arising from basal meningitis like headache, nausea, and/or vomiting; however, presentation with bilateral hearing loss is quite rare. The objective of this case presentation is to include tuberculous meningitis in the differential diagnosis of progressive bilateral hearing loss, and emphasize the importance of early diagnosis and treatment to prevent morbidity and mortality.  相似文献   
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