Results 321 to 330 of about 1,936,418 (346)

Ganglioneuroma: To Operate or Not to Operate

European Journal of Pediatric Surgery, 2013
Ganglioneuroma (GN) is a benign, differentiated variety of neurogenic tumor. It is often asymptomatic and may be diagnosed by serendipity. Surgical removal is the treatment of choice. However, it has been suggested that postoperative complications and sequelae might outweigh the benefits of this approach. The purpose of the present study was to examine
Sara Hernández A. Martín, Barrena S, Juan A. Tovar, Manuel López-Santamaría, Sergio Lopez-Fernandez, Alejandra Vilanova-Sanchez, Purificación García, Leopoldo Martinez, Alba Sanchez-Galan   +8 more
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Operations and compositions in transrecursive operators

Cybernetics and Systems Analysis, 1994
Earlier, the authors introduced classes of alphabetic operators that have greater computational possibilities than classical algorithms. In Dokl. Akad. Nauk SSSR 321, No. 5, 876-879 (1991), they gave a uniform procedure for obtaining such alphabetic operators, which will be called transrecursive operators in what follows.
Mark Burgin, Yu. M. Borodyanskii
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Operations and Operatives

2014
Operation RUVANDIZ-SCHLUCHT (ROWANDUZ GORGE) is said to have been a detailed scheme originally submitted to Hans-Otto Wagner of Abwehr II in 1941 by Paul Leverkuehn of KONO in Istanbul for a 2–3-man parachute team to carry out the demolition of bridges on the 185 km-long, strategic asphalt road, known even today as the Hamilton Road, constructed by the
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On operator algebras and operator ranges [PDF]

Integral Equations and Operator Theory, 1986
Some further results are given and some questions raised concerning operator algebras of countable range multiplicity. An example is given of an abelian range cyclic algebra that does not have finite strict multiplicity. On the other hand it is shown that every uniformly closed abelian range cyclic algebra is strictly cyclic.
Peter Rosenthal, W. E. Longstaff
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Pituitary Incidentaloma: to Operate or Not to Operate ?

Acta Chirurgica Belgica, 2012
The wide use of sophisticated imaging techniques has led to the discovery of asymptomatic pituitary lesions, which are called 'incidentalomas'. Their global prevalence averages 10% whereas that of macroadenomas (> 10 mm) is less than 1%. The most frequently encountered lesions are non-functioning adenomas followed by Rathke's cleft cysts. Physiological
Julian Donckier, Th Gustin
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Commutators of operators

American Journal of Mathematics, 1952
A mathematical formulation of the famous Heisenberg uncertainty principle is that a certain pair of linear transformations P and Q satisfies, after suitable normalizations, the equation PQ - QP = 1. It is easy enough to produce a concrete example of this behavior; consider L2(-∞, +∞) and let P and Q be the differentiation transformation and the ...
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Operations on Closure Operators

1995
Despite the powerful continuity condition, the notion of closure operator is very general. It is therefore important to provide tools for improving a given operator. Fortunately, there is a natural lattice structure for closure operators that allows us to distinguish between properties stable under meet (idempotency, hereditariness, productivity), and ...
W. Tholen, D. Dikranjan
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