The action of local anesthetics, containing a tertiary nitrogen, on mammalian nonmyelinated fibers of the rabbit’s vagus nerve has been analyzed to determine whether the uncharged or the positively charged form of these compounds is responsible for their ability to block impulse conduction. The compounds studied were dibucaine, tetracaine, chlorpromazine, imipramine, and procaine. Impulse condu...

We make several eye movements per second when we explore a visual scene. Each eye movement sweeps the scene's projection across the retina and changes its representation in retinotopic areas of the visual cortex, but we nevertheless perceive a stable world. Here we investigate the neuronal correlates of visual stability in the primary visual cortex. Monkeys were trained to make two saccades alo...

After tooth loss, alveolar bone resorption occurs and causes soft tissue collapse. In the anterior maxilla, this situation becomes a great challenge. Bone volume must be reestablished to allow for proper implant placement. Another challenge is achieving primary closure and improving soft tissue esthetics. Nine patients who were partially edentulous in the anterior maxilla and received 10 palata...

Intracranial self-administration of mu- and delta-opioid agonists was demonstrated in male Long-Evans rats. Independent groups were allowed to lever-press for ventral tegmental area (VTA) microinfusions of morphine, the selective mu agonist [D-Ala2,N-Me-Phe4-Gly5-ol]-enkephalin (DAMGO), the selective delta-agonist [D-Pen2,D-Pen5]-enkephalin (DPDPE), or ineffective drug vehicle. Morphine, DAMGO,...

OBJECTIVE We present a case of femoral artery thrombosis and acute limb ischemia in an infant following attempted femoral venipuncture. Microsurgical reconstruction of the lesion and a review of the literature are described. METHODS Insertion of intravascular catheters is a commonly performed procedure in neonatal and pediatric intensive care units. However, significant iatrogenic injuries to...

Copyright © 2009 Massachusetts Medical Society. A 55-year-old man collapses while jogging through the park. A bystander finds him unconscious and without a pulse and initiates cardiopulmonary resuscitation (CPR) while an ambulance is summoned. On arrival in the emergency room, the patient is in ventricular fibrillation; the partial pressure of oxygen in arterial blood is 200 mm Hg, the pH is 7....

Proximal nerve injury can lead to devastating functional impairment. Because axonal regeneration is slow, timely reinnervation of denervated muscle does not occur. These denervated muscles atrophy and lose function. Sensory protection is a surgical technique thought to prevent denervated muscle impairment using local sensory nerves to provide trophic support to the muscle until motor nerves can...

El Tor and non-O1 strains of Vibrio cholerae were analyzed to determine whether synthesis of secreted hemolysin was influenced by the concentration of iron in the medium. Synthesis of hemolysin was found to be iron regulated in both El Tor and non-O1 isolates. Increased levels of hemolytic activity were detected in supernatants of iron-starved cells. Spontaneous hemolysin-deficient mutants of o...

Restraint and cold stress increase both corticosterone and glycemia, which lead to oxidative damages in hepatic tissue. This study assessed the effect of royal jelly (RJ) supplementation on the corticosterone level, glycemia, plasma enzymes and hepatic antioxidant system in restraint and cold stressed rats. Wistar rats were allocated into no-stress, stress, no-stress supplemented with RJ and st...

A realistic quantum many-body system, characterized by a generic microscopic Hamiltonian, is accessible only through approximation methods. The mean field theories, as the simplest practices of approximation methods, commonly serve as a powerful tool, but unfortunately often violate the symmetry of the Hamiltonian. The conventional BCS theory, as an excellent mean field approach, violates the p...