1,673 research outputs found

    Laparoscopic resection of nonparasitar splenic cyst

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    Government Hospital IMSP SR ACSR, Department of Endoscopy and Miniinvasive Surgery, Al XI-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” din Republica Moldova și cea de-a XXXIII-a Reuniune a Chirurgilor din Moldova „Iacomi-Răzeșu” 27-30 septembrie 2011Introduction: Nonparasitic splenic cysts are rarely disease, and may be congenital or post-traumatic in origin. Traditional management includes total or partial splenectomy, partial cystectomy with marsupialization, percutaneous drainage, and sclerotherapy. A laparoscopic technique used to minimize the risk of splenic loss and cyst recurrence is presented.In the current study, we aimed to evaluate the laparoscopic management of patients with nonparasitic splenic cysts together with their long term follow up progresses.Methods: The cases of 5 patients who underwent surgery for spleen cysts at our hospital over the last 12 years from 1998 to 2010 were analyzed. There are 1 male and 4 female. The mean age was 31 (25 - 36). Symptoms included left upper quadrant pain and there was no history of trauma. Diagnosis was based on ultrasonography (US), and computed tomography (CT) findings. The mean size of cysts was 12 (8 – 15) cm. All patients were managed with laparoscopic partial cystectomy using the diathermic monopolar cutting of the cyst wall and hemostasis by coagulation.Results: All patients had an noncomplicated postoperative course and were discharged home within 3 – 5 days. Operative time was 35 – 90 min., and blood loss was minimal. Pathology finding was a epithelial (mesothelial) cysts. One case (the second of) the operation was finished by laparoscopic splenectomy immediately after resection of the cyst. Decision for splenectomy was caused to marginal bleeding and insufficiency of experience in this kind of procedure. Consecutive follow up in 10 years showed the hyperplasia (6 cm. in diameter) of accessory spleen (initial 1cm. in diameter) in this patient. One patient underwent laparoscopic procedure repeat in two years, but in 3th procedure the spleen was removed because recurrence and infecting of the cyst. Conclusion: 1.Laparoscopic splenic cystectomy can be performed safely. 2.This technique preserves the spleen and minimizes the risk of recurrence of the cyst

    First Measurement of Bose-Einstein Correlations in Proton-Proton Collisions at √s=0.9 and 2.36 TeV at the LHC

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    Bose-Einstein correlations have been measured using samples of proton-proton collisions at 0.9 and 2.36 TeV center-of-mass energies, recorded by the CMS experiment at the CERN Large Hadron Collider. The signal is observed in the form of an enhancement of pairs of same-sign charged particles with small relative four-momentum. The size of the correlated particle emission region is seen to increase significantly with the particle multiplicity of the event

    Transverse-Momentum and Pseudorapidity Distributions of Charged Hadrons in pp Collisions at √s=7  TeV

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    Charged-hadron transverse-momentum and pseudorapidity distributions in proton-proton collisions at √s=7  TeV are measured with the inner tracking system of the CMS detector at the LHC. The charged-hadron yield is obtained by counting the number of reconstructed hits, hit pairs, and fully reconstructed charged-particle tracks. The combination of the three methods gives a charged-particle multiplicity per unit of pseudorapidity dN_(ch)/dη||η|<0.5=5.78±0.01(stat)±0.23(syst) for non-single-diffractive events, higher than predicted by commonly used models. The relative increase in charged-particle multiplicity from √s=0.9 to 7 TeV is [66.1±1.0(stat)±4.2(syst)]%. The mean transverse momentum is measured to be 0.545±0.005(stat)±0.015(syst)  GeV/c. The results are compared with similar measurements at lower energies

    First measurement of hadronic event shapes in pp collisions at √s = 7 TeV

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    Hadronic event shapes have been measured in proton–proton collisions at √s = 7 TeV source, with a data sample collected with the CMS detector at the LHC. The sample corresponds to an integrated luminosity of 3.2 pb^(−1). Event-shape distributions, corrected for detector response, are compared with five models of QCD multijet production

    Measurements of inclusive W and Z cross sections in pp collisions at √s=7 TeV

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    Measurements of inclusive W and Z boson production cross sections in pp collisions at √s = 7 TeV are presented, based on 2.9 pb^(-1) of data recorded by the CMS detector at the LHC. The measurements, performed in the electron and muon decay channels, are combined to give σ(pp → WX) x B (W → lv) = 9.95 ± 0.07 (stat.) ± 0.28 (syst.) ± 1.09 (lumi.) nb and σ(pp → ZX) x B (Z → ℓ+ℓ-) = 0.931 ± 0.026 (stat.) ± 0.023 (syst.) ± 0.102 (lumi.) nb, where ℓ stands for either e or µ. Theoretical predictions, calculated at the next-to-next-to-leading order in QCD using recent parton distribution functions, are in agreement with the measured cross sections. Ratios of cross sections, which incur an experimental systematic uncertainty of less than 4%, are also reported

    Measurement of BB angular correlations based on secondary vertex reconstruction at √s = 7 TeV

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    A measurement of the angular correlations between beauty and anti-beauty hadrons (BB) produced in pp collisions at a centre-of-mass energy of 7 TeV at the CERN LHC is presented, probing for the first time the region of small angular separation. The B hadrons are identified by the presence of displaced secondary vertices from their decays. The B hadron angular separation is reconstructed from the decay vertices and the primary-interaction vertex. The differential BB production cross section, measured from a data sample collected by CMS and corresponding to an integrated luminosity of 3.1 pb^(−1), shows that a sizable fraction of the BB pairs are produced with small opening angles. These studies provide a test of QCD and further insight into the dynamics of bb production

    Charged particle multiplicities in pp interactions at √s = 0.9, 2.36, and 7 TeV

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    Measurements of primary charged hadron multiplicity distributions are presented for non-single-diractive events in proton-proton collisions at centre-of-mass energies of √s = 0.9, 2.36, and 7 TeV, in five pseudorapidity ranges from |η| < 0.5 to |η| < 2.4. The data were collected with the minimum-bias trigger of the CMS experiment during the LHC commissioning runs in 2009 and the 7 TeV run in 2010. The multiplicity distribution at √s = 0.9 TeV is in agreement with previous measurements. At higher energies the increase of the mean multiplicity with √s is underestimated by most event generators. The average transverse momentum as a function of the multiplicity is also presented. The measurement of higher-order moments of the multiplicity distribution confirms the violation of Koba-Nielsen-Olesen scaling that has been observed at lower energies

    Measurement of the B^+ Production Cross Section in pp Collisions at √s=7 TeV

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    Measurements of the total and differential cross sections dσ/dp_T^B and dσ/dy^B for B^+ mesons produced in pp collisions at √s=7  TeV are presented. The data correspond to an integrated luminosity of 5.8  pb^(-1) collected by the CMS experiment operating at the LHC. The exclusive decay B^+→J/ψK^+, with J/ψ→μ^+μ^-, is used to detect B^+ mesons and to measure the production cross section as a function of p_T^B and y^B. The total cross section for p_T^B>5  GeV and |y^B|<2.4 is measured to be 28.1±2.4±2.0±3.1  μb, where the first uncertainty is statistical, the second is systematic, and the last is from the luminosity measurement
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