39 research outputs found

    Primary Lymphoma of the Kidney: Case Report and Review of Literature

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    Lymphomatous involvement of the kidney is often seen as a part of disseminated disease. Characteristics of disease are poor prognosis and survival of less than a year after diagnosis. The primary renal lymphoma is very rare, is usually part of general disease, is difficult to diagnostic, and has a poor prognosis. Noncharacteristic solitary renal masses need to be differentiated from renal cell carcinoma. We present a 73-year-old man with a solitary renal mass treated with partial nephrectomy and histologic diagnosed with a primary lymphoma of the kidney. In the preventive diagnosis, conventional radiology is unsuitable, contrast-enhanced renal ultrasound contributes to the diagnosis, and primary renal biopsy is useful. We reviewed the medical literature and discuss primary renal lymphoma, a rare disease with poor prognosis, whose treatment after postsurgical diagnosis based on chemotherapy with R-CHOP (rituximab plus cyclophosphamide/doxorubicin/vincristine/prednisone)

    Efficacy of vitamin E in the conservative treatment of Peyronie's disease: legend or reality? A controlled study of 70 cases

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    The medical treatment is indicated in the development stage of Peyronie’s disease (PD) for at least 1 year after diagnosis and whenever in case of penile pain. This research was conducted to demonstrate the possible effectiveness of vitamin E in PD treatment, whereas in the scientific literature this topic is much discussed. A total of 70 patients (age:26–69 years, mean: 54.1 ± 9.71) diagnosed with PD were enrolled in a conservative treatment. In addition to medical histories and physical examinations all patients underwent the following tests: International Index of Erectile Function (IIEF) questionnaire, penile ultrasound and photographic documentation, pain evaluation by a conventional 10-point pain scale Visual analogue pain scale (VAS). All 70 patients were divided into two different treatment groups: A and B, with different combinations of drugs: A = vitamin E + verapamil (injection + iontophoresis) + blueberries + propolis + topical diclofenac; B = verapamil (injection + iontophoresis) + blueberries + propolis + topical diclofenac. All patients were treated for 6 months after which they underwent the same follow-up tests as performed prior to the treatment. Intergroup analysis revealed statistically significant differences: in the vitamin E group the effective plaque size reduction was 50.2% whereas in the control group the reduction was 35.8% (p = 0.027). In group A the improvement of curvature occurred in 96.6% of the cases whereas in the control group B this occurred in 48.4% (p = 0.0001), moreover, the mean curvature decrease was respectively 12.25° and 6.73° (p = 0.01). IIEF score was significantly improved in group A patients with comorbidities and erectile dysfunction (p = 0.025). Increase in plaque size occurred only in the control group (17.1%) (p = 0.032). We can affirm that vitamin E can help to prevent the progression of PD. This study strongly supports the recommendation that the best approach for treating PD is multimodal therapy

    Performance of the Electromagnetic Calorimeter of the HERMES Experiment

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    The performance of the electromagnetic calorimeter of the HERMES experiment is described. The calorimeter consists of 840 radiation resistant F101 lead-glass counters. The response to positrons up to 27.5 GeV, the comparison between the measured energy and the momentum reconstructed from tracking, long-term stability, hadron rejection and neutral meson invariant mass reconstruction are shown.Comment: 22 pages, 13 figures, LaTeX, accepted by NI

    Measurement of Angular Distributions and R= sigma_L/sigma_T in Diffractive Electroproduction of rho^0 Mesons

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    Production and decay angular distributions were extracted from measurements of exclusive electroproduction of the rho^0(770) meson over a range in the virtual photon negative four-momentum squared 0.5< Q^2 <4 GeV^2 and the photon-nucleon invariant mass range 3.8< W <6.5 GeV. The experiment was performed with the HERMES spectrometer, using a longitudinally polarized positron beam and a ^3He gas target internal to the HERA e^{+-} storage ring. The event sample combines rho^0 mesons produced incoherently off individual nucleons and coherently off the nucleus as a whole. The distributions in one production angle and two angles describing the rho^0 -> pi+ pi- decay yielded measurements of eight elements of the spin-density matrix, including one that had not been measured before. The results are consistent with the dominance of helicity-conserving amplitudes and natural parity exchange. The improved precision achieved at 47 GeV, reveals evidence for an energy dependence in the ratio R of the longitudinal to transverse cross sections at constant Q^2.Comment: 15 pages, 15 embedded figures, LaTeX for SVJour(epj) document class Revision: Fig. 15 corrected, recent data added to Figs. 10,12,14,15; minor changes to tex

    Observation of a Single-Spin Azimuthal Asymmetry in Semi-Inclusive Pion Electro-Production

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    Single-spin asymmetries for semi-inclusive pion production in deep-inelastic scattering have been measured for the first time. A significant target-spin asymmetry of the distribution in the azimuthal angle phi of the pion relative to the lepton scattering plane was observed for pi+ electro-production on a longitudinally polarized hydrogen target. The corresponding analyzing power in the sin(phi) moment of the cross section is 0.022 +/- 0.005 +/- 0.003. This result can be interpreted as the effect of terms in the cross section involving chiral-odd spin distribution functions in combination with a time-reversal-odd fragmentation function that is sensitive to the transverse polarization of the fragmenting quark.Comment: 5 pages of RevTex, 3 ps figures, 2 table

    Measurement of Longitudinal Spin Transfer to Lambda Hyperons in Deep-Inelastic Lepton Scattering

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    Spin transfer in deep-inelastic Lambda electroproduction has been studied with the HERMES detector using the 27.6 GeV polarized positron beam in the HERA storage ring. For an average fractional energy transfer = 0.45, the longitudinal spin transfer from the virtual photon to the Lambda has been extracted. The spin transfer along the Lambda momentum direction is found to be 0.11 +/- 0.17 (stat) +/- 0.03 (sys); similar values are found for other possible choices for the longitudinal spin direction of the Lambda. This result is the most precise value obtained to date from deep-inelastic scattering with charged lepton beams, and is sensitive to polarized up quark fragmentation to hyperon states. The experimental result is found to be in general agreement with various models of the Lambda spin content, and is consistent with the assumption of helicity conservation in the fragmentation process.Comment: 8 pages, 3 figures; new version has an expanded discussion and small format change

    Beam-Induced Nuclear Depolarisation in a Gaseous Polarised Hydrogen Target

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    Spin-polarised atomic hydrogen is used as a gaseous polarised proton target in high energy and nuclear physics experiments operating with internal beams in storage rings. When such beams are intense and bunched, this type of target can be depolarised by a resonant interaction with the transient magnetic field generated by the beam bunches. This effect has been studied with the HERA positron beam in the HERMES experiment at DESY. Resonances have been observed and a simple analytic model has been used to explain their shape and position. Operating conditions for the experiment have been found where there is no significant target depolarisation due to this effect.Comment: REVTEX, 6 pages, 5 figure

    The Flavor Asymmetry of the Light Quark Sea from Semi-inclusive Deep-inelastic Scattering

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    The flavor asymmetry of the light quark sea of the nucleon is determined in the kinematic range 0.02<x<0.3 and 1 GeV^2<Q^2<10 GeV^2, for the first time from semi-inclusive deep-inelastic scattering. The quantity (dbar(x)-ubar(x))/(u(x)-d(x)) is derived from a relationship between the yields of positive and negative pions from unpolarized hydrogen and deuterium targets. The flavor asymmetry dbar-ubar is found to be non-zero and x dependent, showing an excess of dbar over ubar quarks in the proton.Comment: 7 Pages, 2 figures, RevTeX format; slight revision in text, small change in extraction of dbar-ubar and comparison with a high q2 parameterizatio

    Determination of the Deep Inelastic Contribution to the Generalised Gerasimov-Drell-Hearn Integral for the Proton and Neutron

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    The virtual photon absorption cross section differences [sigma_1/2-sigma_3/2] for the proton and neutron have been determined from measurements of polarised cross section asymmetries in deep inelastic scattering of 27.5 GeV longitudinally polarised positrons from polarised 1H and 3He internal gas targets. The data were collected in the region above the nucleon resonances in the kinematic range nu < 23.5 GeV and 0.8 GeV**2 < Q**2 < 12 GeV**2. For the proton the contribution to the generalised Gerasimov-Drell-Hearn integral was found to be substantial and must be included for an accurate determination of the full integral. Furthermore the data are consistent with a QCD next-to-leading order fit based on previous deep inelastic scattering data. Therefore higher twist effects do not appear significant.Comment: 6 pages, 3 figures, 1 table, revte

    Observation of a Coherence Length Effect in Exclusive Rho^0 Electroproduction

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    Exclusive incoherent electroproduction of the rho^0(770) meson from 1H, 2H, 3He, and 14N targets has been studied by the HERMES experiment at squared four-momentum transfer Q**2>0.4 GeV**2 and positron energy loss nu from 9 to 20 GeV. The ratio of the 14N to 1H cross sections per nucleon, known as the nuclear transparency, was found to decrease with increasing coherence length of quark-antiquark fluctuations of the virtual photon. The data provide clear evidence of the interaction of the quark- antiquark fluctuations with the nuclear medium.Comment: RevTeX, 5 pages, 3 figure
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