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Endotracheal Metastasis Causing Airway Obstruction
Endotracheal metastasis, a critical complication of primary lung cancer, is an extremely rare lesion. A 73-year-old woman who had previously received treatment for lung cancer presented to our emergency department with dyspnea. A chest computed tomography and nasopharyngolaryngoscopy showed an endotracheal mass below the epiglottis, obstructing the trachea almost completely. The patient had an emergency tracheostomy, and then the mass was removed via median laryngotomy. This lesion was proven to be a recurrent metastasis of lung cancer. Clinicians should recognize endotracheal metastasis as an important differential diagnosis in cancer patients presenting with respiratory symptoms
Parabolic isometries of CAT(0) spaces and CAT(0) dimensions
We study discrete groups from the view point of a dimension gap in connection
to CAT(0) geometry. Developing studies by Brady-Crisp and Bridson, we show that
there exist finitely presented groups of geometric dimension 2 which do not act
properly on any proper CAT(0) spaces of dimension 2 by isometries, although
such actions exist on CAT(0) spaces of dimension 3.
Another example is the fundamental group, G, of a complete, non-compact,
complex hyperbolic manifold M with finite volume, of complex-dimension n > 1.
The group G is acting on the universal cover of M, which is isometric to H^n_C.
It is a CAT(-1) space of dimension 2n. The geometric dimension of G is 2n-1. We
show that G does not act on any proper CAT(0) space of dimension 2n-1 properly
by isometries.
We also discuss the fundamental groups of a torus bundle over a circle, and
solvable Baumslag-Solitar groups.Comment: Published by Algebraic and Geometric Topology at
http://www.maths.warwick.ac.uk/agt/AGTVol4/agt-4-38.abs.htm
Dual effect of sympathetic hyperfunction on blood vessels in spontaneously hypertensive and stroke-prone spontaneously hypertensive rats
The sympathetic nervous system has been considered to be hyperactive from the very beginning after birth in spontaneously hypertensive and stroke-prone spontaneously hypertensive rats. This is a primary factor for the development and maintenance of hypertension via structural and functional alterations of the arteries and the heart. It is also described that the sympathetic hyperfunction probably play a protective role in necrosis of vascular smooth muscle cells in spontaneously hypertensive and stroke-prone spontaneously hypertensive rats.Biomedical Reviews 1996; 6: 57-68
Vanishing or non-vanishing rainbow? Reduction formulas of electric dipole moment
In this paper, we derive a simplified formula of electric dipole moments
(EDMs) of a fermion. In the Standard Model, it is well-known that non-trivial
cancellations between some rainbow-type diagrams induced by boson exchanges
occur in the calculation of the neutron EDM at the two-loop level due to the
gauge symmetry. The fermion self-energy and the vertex correction are related
through the Ward-Takahashi identity, and this relation causes the exact
cancellation of the EDM. We derive EDM formulas for a more general setup by
introducing the form factors for the fermion self-energy and the vertex
correction so that the derived formulas can be applicable to a larger class of
models. We conclude that the non-zero EDM contributions are induced from
rainbow-type diagrams with the chirality flipping effects for internal
fermions. We also discuss the other possible generalization of the EDM
calculation which is applicable to the other classes of models.Comment: 23 pages, 7 figures, 2 tables, the version published in JHE
Genome-wide search for strabismus susceptibility loci.
The purpose of this study was to search for chromosomal susceptibility loci for comitant strabismus. Genomic DNA was isolated from 10mL blood taken from each member of 30 nuclear families in which 2 or more siblings are affected by either esotropia or exotropia. A genome-wide search was performed with amplification by polymerase chain reaction of 400 markers in microsatellite regions with approximately 10 cM resolution. For each locus, non-parametric affected sib-pair analysis and non-parametric linkage analysis for multiple pedigrees (Genehunter software, http://linkage.rockefeller.edu/soft/) were used to calculate multipoint lod scores and non-parametric linkage (NPL) scores, respectively. In sib-pair analysis, lod scores showed basically flat lines with several peaks of 0.25 on all chromosomes. In non-parametric linkage analysis for multiple pedigrees, NPL scores showed one peak as high as 1.34 on chromosomes 1, 2, 4, 7, 10, 15, and 16, while 2 such peaks were found on chromosomes 3, 9, 11, 12, 18, and 20. Non-parametric linkage analysis for multiple pedigrees of 30 families with comitant strabismus suggested a number of chromosomal susceptibility loci. Our ongoing study involving a larger number of families will refine the accuracy of statistical analysis to pinpoint susceptibility loci for comitant strabismus.</P></p
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