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N Pomara C A Bagne M Stanley G G Yarbrough 《Progress in neuro-psychopharmacology & biological psychiatry》1986,10(3-5):553-569
The cholinergic hypothesis of memory dysfunction has guided most of the recent proposals for treating the primary symptoms of AD. The efficacy of these treatments has been severely limited. This review examines two major lines of evidence which suggest that the cholinergic hypothesis may have to be expanded and revised. The cholinergic hypothesis focuses on pre-synaptic defects. It assumes cholinoceptive neurons would function normally with adequate stimulation. Evidence is not sufficient to support this assumption. In addition, dissociations have been demonstrated between muscarinic receptor number and functional response of cholinoceptive neurons. Various measures are proposed to investigate the functional integrity of muscarinic receptors in AD patients. AD often has been characterized as a disorder produced by generalized cholinergic hypoactivity. Evidence for cortisol hypersecretion, abnormal dexamethasone suppression, and the occurrence of depressive symptoms, motoric dysfunction and sleep abnormalities in AD patients is more consistent with regional cholinergic hyperactivity than generalized hypoactivity. Resolution of these discrepancies could shed new light on the pathophysiology and treatment strategies for AD. Cholinoceptive neurons could be hypersensitive, subsensitive or have unaltered responsivity. These options would have very different treatment implications. New developments in outcome assessment which are capable of discriminating varieties of differential response to treatment can spur treatment development and improve quality of care for patients with complex disorders such as AD. 相似文献
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Morgan Murphrey BS Samantha Casselman R.N. C.P.N.P. Kevin B. Yarbrough MD 《Pediatric dermatology》2018,35(4):e239-e240
Hand, foot, and mouth disease is a common exanthem linked to infection with several non‐polio enteroviruses. This case of an 11‐year‐old boy with an enteroviral infection limited to areas of sunburn is an atypical presentation of hand, foot, and mouth disease. Recognition of this unusual distribution will allow pediatricians and pediatric dermatologists to appropriately manage and counsel patients and parents. 相似文献
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A base-catalyzed sol–gel approach combined with a solvent-driven self-assembly process at low temperature is augmented to make manganese oxide (Mn3O4), copper oxide (CuO), and magnesium hydroxide (Mg(OH)2) nanostructures with size- and shape-controlled morphologies. Nanostructures of Mn3O4 with either hexagonal, irregular particle, or ribbon shape morphologies with an average diameter ranged from 100 to 200 nm have been prepared in four different solvent types. In all morphologies of Mn3O4, the experimental XRD patterns have indexed the nanocrystal unit cell structure to triclinic. The hexagonal nanoparticles of Mn3O4 exhibit high mesoporocity with a BET surface area of 91.68 m2 g−1 and BJH desorption average pore diameter of ∼28 nm. In the preparation of CuO nanostructures, highly nanoporous thin sheets have been produced in water and water/toluene solvent systems. The simulated XRD pattern matches the experimental XRD patterns of CuO nanostructures and indexes the nanocrystal unit cell structure to monoclinic. With the smallest desorption total pore volume of 0.09 cm3 g−1, CuO nanosheets have yielded the lowest BET surface area of 18.31 m2 g−1 and a BHJ desorption average pore diameter of ∼16 nm. The sol of magnesium hydroxide nanocrystals produces highly nanoporous hexagonal nanoplates in water and water/toluene solvent systems. The wide angle powder XRD patterns show well-defined Bragg''s peaks, indexing to a hexagonal unit cell structure. The hexagonal plates show a significantly high BET surface area (72.31 m2 g−1), which is slightly lower than the surface area of Mn3O4 hexagonal nanoparticles. The non-template driven sol–gel synthesis process demonstrated herein provides a facile method to prepare highly mesoporous and nanoporous nanostructures of binary (II–IV) metal oxides and their hydroxide derivatives, enabling potential nanostructure platforms with high activities and selectivities for catalysis applications.A base-catalyzed sol–gel approach combined with a solvent-driven self-assembly process at low temperature is augmented to make highly mesoporous metal oxide nanostructures of manganese and copper, and hydroxide nanostructures of magnesium. 相似文献
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Hangman's fracture resulting from improper seat belt use 总被引:11,自引:0,他引:11
Diagonal seat belt application without accompanying lap belt closure may produce severe cervical spine injuries, including hangman's fracture and decapitation. Seat belts are effective in reducing injury, but they must be worn properly to do so. Passive restraint systems involving a diagonal seat belt may be hazardous if the motorist does not use the accompanying lap belt. We have presented a case in which the driver in a motor vehicle accident sustained a hangman's fracture (bilateral fracture of the pedicles of C-2) caused by use of a diagonal seat belt without accompanying lap belt closure. The mechanism of injury, as classically described in judicial hanging, is hyperextension and distraction, which occurred when the victim "submarined" under the diagonal seat belt and was caught at the neck. 相似文献
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T C Litton J P Sutton C W Smith W B Allen J W Yarbrough E M Leppard 《American journal of surgery》1988,155(4):587-589
A review of postinfarction ventricular septal defects repaired surgically at Providence Hospital over the past 6 years is presented. Although this complication of myocardial infarction carries a high mortality rate, a lower rate can be achieved with early operative intervention. Preoperative pharmacologic reduction of preload, afterload, and intra-aortic balloon pumping are only temporizing measures to allow delineation of concomitant lesions. Operative mortality does not appear to be influenced by posterior location of the ventricular septal defects. 相似文献