789 research outputs found
An iliac-appendiceal fistula causing gastrointestinal bleeding
© 2019 The Authors Aortoenteric fistulas are an uncommon cause of gastrointestinal bleeding, and iliac-appendiceal fistulas are an even rarer cause. We describe a case of an iliac-appendiceal fistula in a patient who presented several months after aortic reconstruction with gastrointestinal bleeding. An extensive workup revealed that the source of bleeding was localized to the appendiceal orifice. The patient underwent an appendectomy with a two-stage procedure involving the iliac graft for definitive repair and ultimately recovered well. Despite the rarity of aortoenteric and iliac-appendiceal fistulas causing gastrointestinal bleeding, keeping a high index of suspicion in patients with a prior vascular repair can prevent death
Multiple cerebral aneurysms of middle cerebral artery: Case report
Multiple cerebral aneurysms present a wide variation in incidence with averages of 13% at angiographic studies and 22.7% at autopsy. High blood pressue, cigarette smoking, stress and possible also age and female sex seem to be risk factors for multiple intracranial aneurysms (MIAn) in patients of working age who have suffered a subarachnoid hemorrhage (SAH). Aneurysms were situated on the same side in one-third of the patients with two aneurysms and the most common site was the middle cerebral artery (MCA). To manage these challenging lesions neurosurgeons must use all available innovations and advances, including diagnostic, technical and perioperative adjuncts. The author presents a case of middle age female, with two saccular aneurysms situated on the same side (right MCA), who was operated in our clinic, 20 days after first SAH episode, I grade on Hunt/Hess scale. The angio MRI was performed before, and control DS angiography after operation. After pterional approach, the author used the magnification, microsurgical technics, temporal clip, and two permanent Yasargil curved clips. A postoperative good recovery enable the patient go to work and drive one month later
Evaluation of Left Atrial Size and Function: Relevance for Clinical Practice
Left atrial (LA) structural and functional evaluation have recently emerged as powerful biomarkers for adverse events in a variety of cardiovascular conditions. Moreover, noninvasive evaluation of LA pressure has gained importance in the characterization of the hemodynamic profile of patients. This review describes the methodology, benefits and pitfalls of measuring LA size and function by echocardiography and provides a brief overview of the prognostic utility of newer echocardiographic metrics of LA geometry and function (i.e., three-dimensional volumes, longitudinal strain, and phasic function parameters)
New data on OZI rule violation in bar{p}p annihilation at rest
The results of a measurement of the ratio R = Y(phi pi+ pi-) / Y(omega pi+
pi-) for antiproton annihilation at rest in a gaseous and in a liquid hydrogen
target are presented. It was found that the value of this ratio increases with
the decreasing of the dipion mass, which demonstrates the difference in the phi
and omega production mechanisms. An indication on the momentum transfer
dependence of the apparent OZI rule violation for phi production from the 3S1
initial state was found.Comment: 11 pages, 3 PostScript figures, submitted to Physics Letter
Natural Diagonal Riemannian Almost Product and Para-Hermitian Cotangent Bundles
We obtain the natural diagonal almost product and locally product structures
on the total space of the cotangent bundle of a Riemannian manifold. We find
the Riemannian almost product (locally product) and the (almost) para-Hermitian
cotangent bundles of natural diagonal lift type. We prove the characterization
theorem for the natural diagonal (almost) para-K\"ahlerian structures on the
total spaces of the cotangent bundle.Comment: 10 pages, will appear in Czechoslovak Mathematical Journa
Formation of the in Two-Photon Collisions at LEP
The two-photon width of the meson has been
measured with the L3 detector at LEP. The is studied in the decay
modes , KK, KK,
KK, , , and
using an integrated luminosity of 140 pb at GeV and
of 52 pb at GeV. The result is
(BR) keV. The dependence of the cross section is studied for
GeV. It is found to be better described by a Vector Meson
Dominance model form factor with a J-pole than with a -pole. In addition,
a signal of events is observed at the mass. Upper limits
for the two-photon widths of the , , and are also
given
Study of Z Boson Pair Production in e+e- Collisions at LEP at \sqrt{s}=189 GeV
The pair production of Z bosons is studied using the data collected by the L3
detector at LEP in 1998 in e+e- collisions at a centre-of-mass energy of 189
GeV. All the visible final states are considered and the cross section of this
process is measured to be 0.74 +0.15 -0.14 (stat.) +/- 0.04 (syst.) pb. Final
states containing b quarks are enhanced by a dedicated selection and their
production cross section is found to be 0.18 +0.09 -0.07 (stat.) +/- 0.02
(syst.) pb. Both results are in agreement with the Standard Model predictions.
Limits on anomalous couplings between neutral gauge bosons are derived from
these measurements
Search for Scalar Leptons in e+e- collisions at \sqrt{s}=189 GeV
We report the result of a search for scalar leptons in e+e- collisions at 189
GeV centre-of-mass energy at LEP. No evidence for such particles is found in a
data sample of 176 pb^{-1}. Improved upper limits are set on the production
cross sections for these new particles. New exclusion contours in the parameter
space of the Minimal Supersymmetric Standard Model are derived, as well as new
lower limits on the masses of these supersymmetric particles. Under the
assumptions of common gaugino and scalar masses at the GUT scale, we set an
absolute lower limit on the mass of the lightest scalar electron of 65.5 Ge
Direct Observation of Longitudinally Polarised W Bosons
The three different helicity states of W bosons, produced in the reaction
e+e- -> W+W- -> l nu q q~ are studied using leptonic and hadronic W decays at
sqrt{s}=183GeV and 189GeV. The W polarisation is also measured as a function of
the scattering angle between the W- and the direction of the e- beam. The
analysis demonstrates that W bosons are produced with all three helicities, the
longitudinal and the two transverse states. Combining the results from the two
center-of-mass energies and with leptonic and hadronic W decays, the fraction
of longitudinally polarised W bosons is measured to be 0.261 +/- 0.051(stat.)
+/- 0.016(syst.) in agreement with the expectation from the Standard Model
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