4,466 research outputs found
Biliary cystic disease and neoplasia: surgical management
Background Congenital cystic dilatation of the extra- and intrahepatic bile ducts is a rare condition with several potential complications, especially a high risk of malignant degeneration, which may develop from an anomalous arrangement of the pancreatico-biliary ductal junction. Patients Twenty-two patients with cystic dilatation of the biliary tree, subdivided according to the Todani classification, were observed and treated during a 17-year period. The intrahepatic ducts were involved in 15 patients. Results Surgical treatment involved either total excision of extrahepatic cysts, hepatic resection in cases of segmental intrahepatic disease or, in the presence of diffuse intrahepatic disease, a wide biliary-digestive anastomosis performed onto the biliary confluence, with the intent of reducing the risk of neoplastic degeneration. One patient with extensive and symptomatic liver involvement complicated by biliary cirrhosis has already undergone liver transplantation, and another two patients who are currently asymptomatic may require this procedure in future. Neoplastic degeneration was found in three patients (one each of Todani type I, type IVa and type V), or 14% of the series. The postoperative course was complicated by cholangitis in only two patients, who were treated successfully with antibiotics. Except for one patient with a type I cyst complicated by carcinoma, who died 14 months post-operatively, all patients are alive and well at a mean follow-up of eight years (range 8 months to 17 years). Discussion The ideal surgical procedures to cure the disease and prevent malignant degeneration are: (a) complete excision of the extrahepatic biliary cysts; (b) hepatic resection in cases of segmental intrahepatic involvement; (c) wide bilio-digestive anastomosis in cases of multiple intrahepatic involvement, or liver transplantation when this is complicated by secondary biliary cirrhosis
Espectroscopia no infravermelho próximo (NIRS) como ferramenta complementar para a discriminação de sementes do gênero Paspalum.
A espectroscopia no infravermelho próximo (NIRS) é sensível a transições de sobretons, ressonâncias e combinações dos modos vibracionais de ligações químicas
Avaliação do uso do Infravermelho Próximo (NIRS) para distinção entre sementes cheias e sementes chochas de Paspalum notatum Flüggé (Poaceae).
O Banco Ativo de Germoplasma de Paspalum da Embrapa Pecuária Sudeste abriga 538 acessos desse importante gênero de gramíneas
Avaliação do uso do infravermelho próximo (NIRS) para predição de características de sementes do banco ativo de germoplasma de Paspalum.
Paspalum L. (Poaceae) é um gênero de gramíneas com potencial forrageiro
Intercalibration of the barrel electromagnetic calorimeter of the CMS experiment at start-up
Calibration of the relative response of the individual channels of the barrel electromagnetic calorimeter of the CMS detector was accomplished, before installation, with cosmic ray muons and test beams. One fourth of the calorimeter was exposed to a beam of high energy electrons and the relative calibration of the channels, the intercalibration, was found to be reproducible to a precision of about 0.3%. Additionally, data were collected with cosmic rays for the entire ECAL barrel during the commissioning phase. By comparing the intercalibration constants obtained with the electron beam data with those from the cosmic ray data, it is demonstrated that the latter provide an intercalibration precision of 1.5% over most of the barrel ECAL. The best intercalibration precision is expected to come from the analysis of events collected in situ during the LHC operation. Using data collected with both electrons and pion beams, several aspects of the intercalibration procedures based on electrons or neutral pions were investigated
Search for Charginos with a Small Mass Difference with the Lightest Supersymmetric Particle at \sqrt{s} = 189 GeV
A search for charginos nearly mass-degenerate with the lightest
supersymmetric particle is performed using the 176 pb^-1 of data collected at
189 GeV in 1998 with the L3 detector. Mass differences between the chargino and
the lightest supersymmetric particle below 4 GeV are considered. The presence
of a high transverse momentum photon is required to single out the signal from
the photon-photon interaction background. No evidence for charginos is found
and upper limits on the cross section for chargino pair production are set. For
the first time, in the case of heavy scalar leptons, chargino mass limits are
obtained for any \tilde{\chi}^{+-}_1 - \tilde{\chi}^0_1 mass difference
Measurement of W Polarisation at LEP
The three different helicity states of W bosons produced in the reaction e+
e- -> W+ W- -> l nu q q~ at LEP are studied using leptonic and hadronic W
decays. Data at centre-of-mass energies \sqrt s = 183-209 GeV are used to
measure the polarisation of W bosons, and its dependence on the W boson
production angle. The fraction of longitudinally polarised W bosons is measured
to be 0.218 \pm 0.027 \pm 0.016 where the first uncertainty is statistical and
the second systematic, in agreement with the Standard Model expectation
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
Search for Anomalous Couplings in the Higgs Sector at LEP
Anomalous couplings of the Higgs boson are searched for through the processes
e^+ e^- -> H gamma, e^+ e^- -> e^+ e^- H and e^+ e^- -> HZ. The mass range 70
GeV < m_H < 190 GeV is explored using 602 pb^-1 of integrated luminosity
collected with the L3 detector at LEP at centre-of-mass energies
sqrt(s)=189-209 GeV. The Higgs decay channels H -> ffbar, H -> gamma gamma, H
-> Z\gamma and H -> WW^(*) are considered and no evidence is found for
anomalous Higgs production or decay. Limits on the anomalous couplings d, db,
Delta(g1z), Delta(kappa_gamma) and xi^2 are derived as well as limits on the H
-> gamma gamma and H -> Z gamma decay rates
- …