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Performance evaluation of the FastIC readout ASIC with emphasis on Cherenkov emission in TOF-PET. Phys Med Biol 2024; 69:115014. [PMID: 38657637 DOI: 10.1088/1361-6560/ad42fe] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2023] [Accepted: 04/24/2024] [Indexed: 04/26/2024]
Abstract
Objective.The efficient usage of prompt photons like Cherenkov emission is of great interest for the design of the next generation, cost-effective, and ultra-high-sensitivity time-of-flight positron emission tomography (TOF-PET) scanners. With custom, high power consuming, readout electronics and fast digitization the prospect of sub-300 ps FWHM with PET-sized BGO crystals have been shown. However, these results are not scalable to a full system consisting of thousands of detector elements.Approach.To pave the way toward a full TOF-PET scanner, we examine the performance of the FastIC ASIC with Cherenkov-emitting scintillators (BGO), together with one of the most recent SiPM detector developments based on metal trenching from FBK. The FastIC is a highly configurable ASIC with 8 input channels, a power consumption of 12 mW ch-1and excellent linearity on the energy measurement. To put the timing performance of the FastIC into perspective, comparison measurements with high-power consuming readout electronics are performed.Main results.We achieve a best CTR FWHM of 330 ps for 2 × 2 × 3 mm3and 490 ps for 2 × 2 × 20 mm3BGO crystals with the FastIC. In addition, using 20 mm long LSO:Ce:Ca crystals, CTR values of 129 ps FWHM have been measured with the FastIC, only slightly worse to the state-of-the-art of 95 ps obtained with discrete HF electronics.Significance.For the first time, the timing capability of BGO with a scalable ASIC has been evaluated. The findings underscore the potential of the FastIC ASIC in the development of cost-effective TOF-PET scanners with excellent timing characteristics.
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On timing-optimized SiPMs for Cherenkov detection to boost low cost time-of-flight PET. Phys Med Biol 2023; 68:165016. [PMID: 37467766 PMCID: PMC10410404 DOI: 10.1088/1361-6560/ace8ee] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 07/10/2023] [Accepted: 07/19/2023] [Indexed: 07/21/2023]
Abstract
Objective.Recent SiPM developments and improved front-end electronics have opened new doors in TOF-PET with a focus on prompt photon detection. For instance, the relatively high Cherenkov yield of bismuth-germanate (BGO) upon 511 keV gamma interaction has triggered a lot of interest, especially for its use in total body positron emission tomography (PET) scanners due to the crystal's relatively low material and production costs. However, the electronic readout and timing optimization of the SiPMs still poses many questions. Lab experiments have shown the prospect of Cherenkov detection, with coincidence time resolutions (CTRs) of 200 ps FWHM achieved with small pixels, but lack system integration due to an unacceptable high power uptake of the used amplifiers.Approach.Following recent studies the most practical circuits with lower power uptake (<30 mW) have been implemented and the CTR performance with BGO of newly developed SiPMs from Fondazione Bruno Kessler tested. These novel SiPMs are optimized for highest single photon time resolution (SPTR).Main results.We achieved a best CTR FWHM of 123 ps for 2 × 2 × 3 mm3and 243 ps for 3 × 3 × 20 mm3BGO crystals. We further show that with these devices a CTR of 106 ps is possible using commercially available 3 × 3 × 20 mm3LYSO:Ce,Mg crystals. To give an insight in the timing properties of these SiPMs, we measured the SPTR with black coated PbF2of 2 × 2 × 3 mm3size. We confirmed an SPTR of 68 ps FWHM published in literature for standard devices and show that the optimized SiPMs can improve this value to 42 ps. Pushing the SiPM bias and using 1 × 1 mm2area devices we measured an SPTR of 28 ps FWHM.Significance.We have shown that advancements in readout electronics and SiPMs can lead to improved CTR with Cherenkov emitting crystals. Enabling time-of-flight with BGO will trigger a high interest for its use in low-cost and total-body PET scanners. Furthermore, owing to the prompt nature of Cherenkov emission, future CTR improvements are conceivable, for which a low-power electronic implementation is indispensable. In an extended discussion we will give a roadmap to best timing with prompt photons.
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ENUBET: A monitored neutrino beam for high precision cross section measurements. EPJ WEB OF CONFERENCES 2023. [DOI: 10.1051/epjconf/202328201018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023] Open
Abstract
The main source of systematic uncertainty on neutrino cross section measurements at the GeV scale is represented by the poor knowledge of the initial flux. The goal of cutting down this uncertainty to 1% can be achieved through the monitoring of charged leptons produced in association with neutrinos, by properly instrumenting the decay region of a conventional narrow-band neutrino beam. Large angle muons and positrons from kaons are measured by a sampling calorimeter on the decay tunnel walls (tagger), while muon stations after the hadron dump can be used to monitor the neutrino component from pion decays. This instrumentation can provide a full control on both the muon and electron neutrino fluxes at all energies. Furthermore, the narrow momentum width (<10%) of the beam provides a O(10%) measurement of the neutrino energy on an event by event basis, thanks to its correlation with the radial position of the interaction at the neutrino detector. The ENUBET project has been funded by the ERC in 2016 to prove the feasibility of such a monitored neutrino beam and is cast in the framework of the CERN neutrino platform (NP06) and the Physics Beyond Colliders initiative. In our contribution, we summarize the ENUBET design, physics performance and opportunities for its implementation in a timescale comparable with next long baseline neutrino experiments.
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Vacuum ultraviolet silicon photomultipliers applied to BaF 2cross-luminescence detection for high-rate ultrafast timing applications. Phys Med Biol 2021; 66. [PMID: 33794510 DOI: 10.1088/1361-6560/abf476] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Accepted: 04/01/2021] [Indexed: 11/11/2022]
Abstract
Inorganic scintillators are widely used for fast timing applications in high-energy physics (HEP) experiments, time-of-flight positron emission tomography and time tagging of soft and hard x-ray photons at advanced light sources. As the best coincidence time resolution (CTR) achievable is proportional to the square root of the scintillation decay time it is worth studying fast cross-luminescence, for example in BaF2which has an intrinsic yield of about 1400 photons/MeV. However, emission bands in BaF2are located in the deep-UV at 195 nm and 220 nm, which sets severe constraints on photodetector selection. Recent developments in dark matter and neutrinoless double beta decay searches have led to silicon photomultipliers (SiPMs) with photon detection efficiencies of 20%-25% at wavelengths of 200 nm. We tested state-of-the-art devices from Fondazione Bruno Kessler and measured a best CTR of 51 ± 5 ps full width at half maximum when coupling 2 mm × 2 mm × 3 mm BaF2crystals excited by 511 keV electron-positron annihilation gammas. Using these vacuum ultraviolet SiPMs we recorded the scintillation kinetics of samples from Epic Crystal under 511 keV excitation, confirming a fast decay time of 855 ps with 12.2% relative light yield and 805 ns with 84.0% abundance, together with a smaller rise time of 4 ps beyond the resolution of our setup. The total intrinsic light yield was determined to be 8500 photons/MeV. We also revealed a faster component with 136 ps decay time and 3.7% light yield contribution, which is extremely interesting for the fastest timing applications. Timing characteristics and CTR results on BaF2samples from different producers and with different dopants (yttrium, cadmium and lanthanum) are given, and clearly show that the the slow 800 ns emission can be effectively suppressed. Such results ultimately pave the way for high-rate ultrafast timing applications in medical diagnosis, range monitoring in proton or heavy ion therapy and HEP.
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Dual-ended readout of bismuth germanate to improve timing resolution in time-of-flight PET. Phys Med Biol 2019; 64:105007. [PMID: 30978713 DOI: 10.1088/1361-6560/ab18da] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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NUV-Sensitive Silicon Photomultiplier Technologies Developed at Fondazione Bruno Kessler. SENSORS 2019; 19:s19020308. [PMID: 30646553 PMCID: PMC6359208 DOI: 10.3390/s19020308] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 12/09/2018] [Accepted: 12/30/2018] [Indexed: 11/16/2022]
Abstract
Different applications require different customizations of silicon photomultiplier (SiPM) technology. We present a review on the latest SiPM technologies developed at Fondazione Bruno Kessler (FBK, Trento), characterized by a peak detection efficiency in the near-UV and customized according to the needs of different applications. Original near-UV sensitive, high-density SiPMs (NUV-HD), optimized for Positron Emission Tomography (PET) application, feature peak photon detection efficiency (PDE) of 63% at 420 nm with a 35 um cell size and a dark count rate (DCR) of 100 kHz/mm2. Correlated noise probability is around 25% at a PDE of 50% at 420 nm. It provides a coincidence resolving time (CRT) of 100 ps FWHM (full width at half maximum) in the detection of 511 keV photons, when used for the readout of LYSO(Ce) scintillator (Cerium-doped lutetium-yttrium oxyorthosilicate) and down to 75 ps FWHM with LSO(Ce:Ca) scintillator (Cerium and Calcium-doped lutetium oxyorthosilicate). Starting from this technology, we developed three variants, optimized according to different sets of specifications. NUV-HD–LowCT features a 60% reduction of direct crosstalk probability, for applications such as Cherenkov telescope array (CTA). NUV-HD–Cryo was optimized for cryogenic operation and for large photosensitive areas. The reference application, in this case, is the readout of liquid, noble-gases scintillators, such as liquid Argon. Measurements at 77 K showed a remarkably low value of the DCR of a few mHz/mm2. Finally, vacuum-UV (VUV)-HD features an increased sensitivity to VUV light, aiming at direct detection of photons below 200 nm. PDE in excess of 20% at 175 nm was measured in liquid Xenon. In the paper, we discuss the specifications on the SiPM related to different types of applications, the SiPM design challenges and process optimizations, and the results from the experimental characterization of the different, NUV-sensitive technologies developed at FBK.
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Characterization of the Detection Module of the INSERT SPECT/MRI Clinical System. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2018. [DOI: 10.1109/trpms.2018.2864792] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Performance of a high-resolution depth-encoding PET detector module using linearly-graded SiPM arrays. Phys Med Biol 2018; 63:035035. [PMID: 29324437 PMCID: PMC5823499 DOI: 10.1088/1361-6560/aaa707] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The goal of this study was to exploit the excellent spatial resolution characteristics of a position-sensitive silicon photomultiplier (SiPM) and develop a high-resolution depth-of-interaction (DOI) encoding positron emission tomography (PET) detector module. The detector consists of a 30 × 30 array of 0.445 × 0.445 × 20 mm3 polished LYSO crystals coupled to two 15.5 × 15.5 mm2 linearly-graded SiPM (LG-SiPM) arrays at both ends. The flood histograms show that all the crystals in the LYSO array can be resolved. The energy resolution, the coincidence timing resolution and the DOI resolution were 21.8 ± 5.8%, 1.23 ± 0.10 ns and 3.8 ± 1.2 mm, respectively, at a temperature of -10 °C and a bias voltage of 35.0 V. The performance did not degrade significantly for event rates of up to 130 000 counts s-1. This detector represents an attractive option for small-bore PET scanner designs that simultaneously emphasize high spatial resolution and high detection efficiency, important, for example, in preclinical imaging of the rodent brain with neuroreceptor ligands.
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Reaching 200-ps timing resolution in a time-of-flight and depth-of-interaction positron emission tomography detector using phosphor-coated crystals and high-density silicon photomultipliers. J Med Imaging (Bellingham) 2016; 3:043501. [PMID: 27921069 DOI: 10.1117/1.jmi.3.4.043501] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 10/28/2016] [Indexed: 12/14/2022] Open
Abstract
Current research in the field of positron emission tomography (PET) focuses on improving the sensitivity of the scanner with thicker detectors, extended axial field-of-view, and time-of-flight (TOF) capability. These create the need for depth-of-interaction (DOI) encoding to correct parallax errors. We have proposed a method to encode DOI using phosphor-coated crystals. Our initial work using photomultiplier tubes (PMTs) demonstrated the possibilities of the proposed method, however, a major limitation of PMTs for this application is poor quantum efficiency in yellow light, corresponding to the wavelengths of the converted light by the phosphor coating. In contrast, the red-green-blue-high-density (RGB-HD) silicon photomultipliers (SiPMs) have a high photon detection efficiency across the visible spectrum. Excellent coincidence resolving time (CRT; [Formula: see text]) was obtained by coupling RGB-HD SiPMs and [Formula: see text] lutetium fine silicate crystals coated on a third of one of their lateral sides. Events were classified in three DOI bins ([Formula: see text] width) with an average sensitivity of 83.1%. A CRT of [Formula: see text] combined with robust DOI encoding is a marked improvement in the phosphor-coated approach that we pioneered. For the first time, we read out these crystals with SiPMs and clearly demonstrated the potential of the RGB-HD SiPMs for this TOF-DOI PET detector.
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Abstract
Bismuth germanate (BGO) was a very attractive scintillator in early-generation positron emission tomography (PET) scanners. However, the major disadvantages of BGO are lower light yield and longer rise and decay time compared to currently popular scintillators such as LSO and LYSO. This results in poorer coincidence timing resolution and it has generally been assumed that BGO is not a suitable scintillator for time-of-flight (TOF) PET applications. However, when a 511 keV photon interacts in a scintillator, a number of Cerenkov photons are produced promptly by energetic electrons released by photoelectric or Compton interactions. If these prompt photons can be captured, they could provide a better timing trigger for PET. Since BGO has a high refractive index (increasing the Cerenkov light yield) and excellent optical transparency down to 320 nm (Cerenkov light yield is higher at shorter wavelengths), we hypothesized that the coincidence timing resolution of BGO can be significantly improved by efficient detection of the Cerenkov photons. However, since the number of Cerenkov photons is far less than the number of scintillation photons, and they are more abundant in the UV and blue part of the spectrum, photosensors need to have high UV/blue sensitivity, fast temporal response, and very low noise in order to trigger on the faint Cerenkov signal. In this respect, NUV-HD silicon photomultipliers (SiPMs) (FBK, Trento, Italy) are an excellent fit for our approach. In this study, coincidence events were measured using BGO crystals coupled with NUV-HD SiPMs. The existence and influence of Cerenkov photons on the timing measurements were studied using different configurations to exploit the directionality of the Cerenkov emissions. Coincidence resolving time values (FWHM) of ~270 ps from 2 × 3 × 2 mm3 BGO crystals and ~560 ps from 3 × 3 × 20 mm3 BGO crystals were obtained. To our knowledge, these are the best coincidence resolving time values reported for BGO to date. With these values, BGO can be considered as a relevant scintillator for TOF PET scanners, especially if photodetectors with even better near UV/blue response can be developed to further improve the efficiency of Cerenkov light detection.
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First results with SiPM tiles for TOF PET based on FBK RGB-HD technology. EJNMMI Phys 2015; 2:A86. [PMID: 26956348 PMCID: PMC4798611 DOI: 10.1186/2197-7364-2-s1-a86] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Sub-100 ps coincidence time resolution for positron emission tomography with LSO:Ce codoped with Ca. Phys Med Biol 2015; 60:4635-49. [DOI: 10.1088/0031-9155/60/12/4635] [Citation(s) in RCA: 111] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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ECONOMIC ANALYSIS OF COSTS FOR PATIENTS WITH END STAGE LIVER DISEASE OVER THE LAST YEAR OF LIFE. BMJ Support Palliat Care 2015. [DOI: 10.1136/bmjspcare-2014-000838.23] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Timing and Energy Resolution of new near-UV SiPMs coupled to LaBr 3:Ce for TOF-PET. IEEE TRANSACTIONS ON NUCLEAR SCIENCE 2014; 61:2426-2432. [PMID: 25530626 PMCID: PMC4266942 DOI: 10.1109/tns.2014.2346579] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The high light output and fast decay time of LaBr3:Ce scintillation detectors leads to excellent timing performance. To realize the potential of timing resolution with LaBr3:Ce we have investigated the performance with SiPMs, which enable 1-to-1 coupling to individual crystals, and which have been optimized for the near-ultraviolet (NUV) scintillation light emission of LaBr3:Ce. Coincidence timing resolution (CTR) of 100 ps was measured for a 4×4×5 mm3 LaBr3:30%Ce crystal directly coupled to a large-area 4×4 mm2 NUV-SiPM. Results show very little dependence on temperature, in the range of -20° to 20°C, and bias voltage, from 2 V to 5 V over breakdown. Optimal performance was achieved at an over-voltage (OV) range of 3 V - 5 V, at which high gain and high photon detection efficiency are achieved. Though saturation was evident at 511 keV, an energy resolution of 6.8% was measured after correcting for non-linearity. We also measured a CTR of 110 ps for a 4×4×5mm3 LaBr3:5%Ce crystal and 245 ps for a 4×4×30 mm3 LaBr3:5%Ce crystal using the NUV-SIPM. The poorer timing measurement for the 30-mm long crystal is due mainly to a systematic shift in the time pick-off as a function of the depth-of-interaction. The excellent temperature stability, fast rise time, high gain, and low noise of the NUV-SiPM make it a practical and highly appealing photodetector for the readout of a LaBr3:Ce TOF-PET detector.
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Characterization of linearly graded position-sensitive silicon photomultipliers. EJNMMI Phys 2014; 1:A14. [PMID: 26501599 PMCID: PMC4546021 DOI: 10.1186/2197-7364-1-s1-a14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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SiPM optical crosstalk amplification due to scintillator crystal: effects on timing performance. Phys Med Biol 2014; 59:3615-35. [DOI: 10.1088/0031-9155/59/13/3615] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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DO INDIVIDUALS WITH SEVERE MENTAL ILLNESS RECEIVE EQUITABLE CARE IN THE LAST YEAR OF LIFE? BMJ Support Palliat Care 2014. [DOI: 10.1136/bmjspcare-2014-000653.45] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Performance of FBK high-density SiPM technology coupled to Ce:LYSO and Ce:GAGG for TOF-PET. Phys Med Biol 2014; 59:869-80. [DOI: 10.1088/0031-9155/59/4/869] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Abstract
Detectors for simultaneous positron emission tomography and magnetic resonance imaging in particular with sub-mm spatial resolution are commonly composed of scintillator crystal arrays, readout via arrays of solid state sensors, such as avalanche photo diodes (APDs) or silicon photomultipliers (SiPMs). Usually a light guide between the crystals and the sensor is used to enable the identification of crystals which are smaller than the sensor elements. However, this complicates crystal identification at the gaps and edges of the sensor arrays. A solution is to use as many sensors as crystals with a direct coupling, which unfortunately increases the complexity and power consumption of the readout electronics. Since 1997, position-sensitive APDs have been successfully used to identify sub-mm crystals. Unfortunately, these devices show a limitation in their time resolution and a degradation of spatial resolution when placed in higher magnetic fields. To overcome these limitations, this paper presents a new sensor concept that extends conventional SiPMs by adding position information via the spatial encoding of the channel sensitivity. The concept allows a direct coupling of high-resolution crystal arrays to the sensor with a reduced amount of readout channels. The theory of sensitivity encoding is detailed and linked to compressed sensing to compute unique sparse solutions. Two devices have been designed using one- and two-dimensional linear sensitivity encoding with eight and four readout channels, respectively. Flood histograms of both devices show the capability to precisely identify all 4 × 4 LYSO crystals with dimensions of 0.93 × 0.93 × 10 mm(3). For these crystals, the energy and time resolution (MV ± SD) of the devices with one (two)-dimensional encoding have been measured to be 12.3 · (1 ± 0.047)% (13.7 · (1 ± 0.047)%) around 511 keV with a paired coincidence time resolution (full width at half maximum) of 462 · (1 ± 0.054) ps (452 · (1 ± 0.078) ps).
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Abstract
The hypothesis that single low-dose exposures (0.025-0.5 Gy) to low-LET radiation given at either high (about 150 mGy/min) or low (1 mGy/min) dose rate would promote aortic atherosclerosis was tested in female C57BL/6J mice genetically predisposed to this disease (ApoE⁻/⁻). Mice were exposed either at an early stage of disease (2 months of age) and examined 3 or 6 months later or at a late stage of disease (8 months of age) and examined 2 or 4 months later. Changes in aortic lesion frequency, size and severity as well as total serum cholesterol levels and the uptake of lesion lipids by lesion-associated macrophages were assessed. Statistically significant changes in each of these measures were observed, depending on dose, dose rate and disease stage. In all cases, the results were distinctly non-linear with dose, with maximum effects tending to occur at 25 or 50 mGy. In general, low doses given at low dose rate during either early- or late-stage disease were protective, slowing the progression of the disease by one or more of these measures. Most effects appeared and persisted for months after the single exposures, but some were ultimately transitory. In contrast to exposure at low dose rate, high-dose-rate exposure during early-stage disease produced both protective and detrimental effects, suggesting that low doses may influence this disease by more than one mechanism and that dose rate is an important parameter. These results contrast with the known, generally detrimental effects of high doses on the progression of this disease in the same mice and in humans, suggesting that a linear extrapolation of the known increased risk from high doses to low doses is not appropriate.
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Abstract
In this work, we present the results of the experimental characterization of the DRAGO (DRift detector Array-based Gamma camera for Oncology), a detection system developed for high-spatial resolution gamma-ray imaging. This camera is based on a monolithic array of 77 silicon drift detectors (SDDs), with a total active area of 6.7 cm(2), coupled to a single 5-mm-thick CsI(Tl) scintillator crystal. The use of an array of SDDs provides a high quantum efficiency for the detection of the scintillation light together with a very low electronics noise. A very compact detection module based on the use of integrated readout circuits was developed. The performances achieved in gamma-ray imaging using this camera are reported here. When imaging a 0.2 mm collimated (57)Co source (122 keV) over different points of the active area, a spatial resolution ranging from 0.25 to 0.5 mm was measured. The depth-of-interaction capability of the detector, thanks to the use of a Maximum Likelihood reconstruction algorithm, was also investigated by imaging a collimated beam tilted to an angle of 45 degrees with respect to the scintillator surface. Finally, the imager was characterized with in vivo measurements on mice, in a real preclinical environment.
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Abstracts: Cardiac arrhythmias - non invasive analysis of mechanisms. Europace 2009. [DOI: 10.1093/europace/euq234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Left ventricular function in colon cancer patients receiving adjuvant fluoro-folate chemotherapy: an echocardiographic study. Oncol Rep 2000; 7:887-90. [PMID: 10854564 DOI: 10.3892/or.7.4.887] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cardiotoxicity has been reported with increasing frequency after 5-FU administration. Since 5-FU-based regimens are increasingly used as adjuvant treatment for resected colon cancer patients, this carries a potential increased risk of cardiotoxicity. In the present study, we evaluated if fluoro-folate chemotherapy has any effect on left ventricular (LV) diastolic function in resected colon cancer. Twenty-five resected colon cancer patients receiving adjuvant fluoro-folate chemotherapy, were prospectively studied. Both digitized M-mode and Doppler echocardiography were performed, in order to investigate different aspects of LV diastolic function. None of the studied parameters was influenced by chemotherapy administration. Indeed, values recorded at the end of the 6-month treatment and 6 months later were not statistically different from baseline values. This study suggests that the use of fluoro-folate chemotherapy in otherwise normal subjects carries a very low risk of severe cardiotoxicity.
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Left ventricular diastolic function in scleroderma. BRITISH JOURNAL OF RHEUMATOLOGY 1997; 36:609-10. [PMID: 9189071 DOI: 10.1093/rheumatology/36.5.609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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[Pulmonary venous flow in patients with chronic heart failure: feasibility and additional value compared to transmitral flow for non-invasive estimation of pulmonary wedge pressure]. GIORNALE ITALIANO DI CARDIOLOGIA 1996; 26:1123-37. [PMID: 9005158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND In many cardiac conditions, Doppler of transmitral flow has been showed to be related to left ventricular filling pressure, but several factors may limit its practical value in estimating pulmonary wedge pressure in patients with chronic heart failure. Pulmonary venous velocities directly depend on the oscillations of left atrial pressure. Recent studies suggest that transthoracic Doppler of pulmonary venous flow provides a more accurate estimation of pulmonary wedge pressure. However the relative values of transmitral and pulmonary venous flow for assessing pulmonary wedge pressure in patients with chronic heart failure have not been fully classified until now. Accordingly, we performed this study to assess the feasibility of transthoracic Doppler of pulmonary venous flow in patients with chronic heart failure and to evaluate whether it provides additional information regarding pulmonary wedge pressure when compared with Doppler indices of transmitral flow. METHODS Simultaneous Doppler echocardiographic examinations and right heart catheterizations were performed prospectively in 300 consecutive patients with chronic heart failure due to dilated cardiomyopathy. The correlations of mitral and pulmonary venous flow velocity variables, left atrial volumes, mitral regurgitation jet area and left ventricular ejection fraction with pulmonary artery wedge pressure were evaluated. RESULTS A complete recording of transthoracic pulmonary venous flow including all components was obtained in 66% of patients, while only systolic and diastolic forward flow were recorded in 88% of patients. Several indices, derived from pulmonary venous flow, were correlated with pulmonary wedge pressure; the strongest correlation was between systolic fraction of peak velocities and pulmonary wedge pressure (r = -0.76). This value was similar to that obtained between deceleration rate (r = 0.78) and deceleration time (r = -0.67) of transmitral flow and pulmonary wedge pressure. A systolic fraction > 40% showed a greater positive predictive value than restrictive pattern of transmitral flow for identifying patients with pulmonary wedge pressure > 18 mmHg (95% vs 86% p < 0.05). This accuracy is confirmed also in patients who had a single peak of transmitral flow. CONCLUSIONS Doppler of pulmonary venous flow can be performed in a high percentage of patients with chronic heart failure due to dilated cardiomyopathy. The indices derived from transthoracic pulmonary venous flow are strongly correlated with pulmonary wedge pressure and improve the noninvasive identification of patients with high pulmonary wedge pressure, even when transmitral flow pattern is difficult to be interpreted.
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Comparison of Doppler echocardiography with thermodilution for assessing cardiac output in advanced congestive heart failure. Am J Cardiol 1996; 78:708-12. [PMID: 8831417 DOI: 10.1016/s0002-9149(96)00406-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Noninvasive cardiac output estimation by Doppler echocardiography was compared with thermodilution and Fick oxygen methods in 73 patients with advanced chronic congestive heart failure due to dilated cardiomyopathy. In these patients, Doppler echocardiographic measurements showed a closer agreement with Fick measurements than that of thermodilution.
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29
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[Chronic granulocytic leukemia and an organ neoplasm in the same person]. POLSKI TYGODNIK LEKARSKI (WARSAW, POLAND : 1960) 1996; 51:289-290. [PMID: 9289713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Among 200 patients treated for chronic granulocytic leukaemia (CGL) 6 (3%) cases have been selected in whom a second synchronic or metachronic neoplasma coexisted. In one patient CGL was the first neoplasma and skin basalioma the second in line. In the remaining fife; Thyroid adenocarcinoma, adeno-carcinoma of the bowl (bis), epithelial carcinoma of the penis, epithelial carcinoma of the pulmonary, were followed respectively CGL as secondary tumor in same patient.
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30
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Cryptococcal infection and lymphogranulomatous infiltration of the central nervous system in Hodgkin's disease. Mycoses 1994; 37:439-41. [PMID: 7659133 DOI: 10.1111/j.1439-0507.1994.tb00396.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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31
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[Results of alternating treatment of multiple myeloma--cytostatics VBMCP and recombinant interferon alfa-2B]. POLSKIE ARCHIWUM MEDYCYNY WEWNETRZNEJ 1993; 90:134-41. [PMID: 8247946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
In 19 patients with recently diagnosed multiple myeloma 3-week cycles of vincristine, BCNU, melphalan, cyclophosphamide and prednisone alternating with interferon were administered over 6-12 months. Results were compared with a control group of 33 myeloma patients treated exclusively with VBMCP cytostatics. In interferon treated patients objective response was more frequent (76%) and median survival time longer (above 35 months).
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32
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Determinants of left ventricular function before and after regression of myocardial hypertrophy in hypertension. Am J Hypertens 1993; 6:708-12. [PMID: 8217034 DOI: 10.1093/ajh/6.8.708] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Using digitized M-mode echocardiograms, we evaluated the determinants of left ventricular (LV) systolic and diastolic function in 30 hypertensives with LV hypertrophy (LV mass > 230 g and normal LV diastolic diameter), before (LV mass 319 +/- 26 g) and after normalization of LV mass (196 +/- 21 g) by antihypertensive treatment with angiotensin converting enzyme inhibitors. As a control group we selected 50 normal subjects. Using multiple regression analysis we studied the relative role of preload (LV end-diastolic diameter), afterload (end-systolic wall stress), inotropic state (systolic pressure/end-systolic LV diameter ratio), and LV mass on LV systolic (peak shortening rate of LV diameter) and diastolic function (peak lengthening rate of LV diameter). The major determinant of systolic function was the end-systolic stress in hypertensives before treatment and the systolic pressure/end-systolic LV diameter ratio in normals and in hypertensives after treatment. The major determinant of diastolic function was LV mass in hypertensives before treatment and end-systolic stress in normals and in hypertensives after normalization of LV mass by treatment. Preload seems not to influence LV function in normals and in hypertensives with normal LV diameter. The inotropic state is the major determinant of systolic function in normals and in hypertensives after treatment, whereas this role is played by afterload in hypertensives before treatment. The diastolic function is primarily influenced by after-load in normals and in hypertensives after regression of myocardial hypertrophy, whereas in hypertensives with myocardial hypertrophy LV mass is the major determinant of diastolic function.
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33
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[Treatment of blood hyperviscosity syndrome with continuous plasma exchange using a Fenval CS 3000 separator in patients with multiple myeloma]. POLSKI TYGODNIK LEKARSKI (WARSAW, POLAND : 1960) 1993; 48:123-5. [PMID: 8361907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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34
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[Neoplastic diseases of the hematopoietic system and ischemia of the lower limbs]. POLSKI TYGODNIK LEKARSKI (WARSAW, POLAND : 1960) 1991; 46:697-9. [PMID: 1669135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The possible interaction between hematopoietic neoplasms and ischemia of the lower limbs in patients with both pathologies was subjected to analysis. Anaemia, polycythemia, thrombocythemia, increased leucocytosis in the peripheral blood, and hyperuricemia exerted unfavourable effect on the blood flow through the arteries of the lower limbs. In some cases effective cytostatic treatment diminished the ischemia of the lower limbs. Interactions between various drugs used in the chronic treatment of both pathologies in the same patient was also examined.
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35
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[Analysis of the prognostic significance of serum immunoglobulins in Hodgkin's disease]. POLSKIE ARCHIWUM MEDYCYNY WEWNETRZNEJ 1991; 85:50-8. [PMID: 2038576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Main classes of serum immunoglobulins have been studied in plasma of patients with untreated Hodgkin's disease and correlations have been analyzed between their levels and the clinical stage of the disease, its histological type and the patient's age and survival. In the Hematology Department, Wrocław, in the years 1979-1989 to the study 115 cases were qualified, 59 were female, 56 male, 75 are still under treatment, whereas 40 died. Stage III B and IV B and histological type NS and MC prevailed. Mathematical analysis resulted in the following: In untreated Hodgkin's disease plasma levels of IgA, IgG, IgM were elevated compared to the controls. No correlation was found of the immunoglobulins elevations to the patients age, histological type, clinical stage and survival.
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36
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[Plasmapheresis and plasma exchange in the treatment of internal diseases]. POLSKIE ARCHIWUM MEDYCYNY WEWNETRZNEJ 1989; 81:41-5. [PMID: 2694116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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37
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[Cryptococcal cerebrospinal meningitis as a complication of acute blast crisis of chronic myeloid leukemia]. POLSKI TYGODNIK LEKARSKI (WARSAW, POLAND : 1960) 1988; 43:746-7. [PMID: 3237514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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38
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[Results of the combined treatment of advanced multiple myeloma by the M-2 protocol: cyclophosphamide, vincristine, melphalan, nitrosourea and prednisone]. POLSKIE ARCHIWUM MEDYCYNY WEWNETRZNEJ 1987; 77:200-5. [PMID: 3078182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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39
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[Bone marrow damage in chronic fluoride poisoning after ingestion of large amounts of fluoridated toothpaste]. POLSKIE ARCHIWUM MEDYCYNY WEWNETRZNEJ 1986; 76:274-7. [PMID: 3601728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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40
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[Prof. Edward Szczeklik--a Polish physician and scientist 1898-1985]. POLSKIE ARCHIWUM MEDYCYNY WEWNETRZNEJ 1986; 76:70-2. [PMID: 3543870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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41
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[Serum immunoglobulins in non-Hodgkin's lymphoma]. POLSKI TYGODNIK LEKARSKI (WARSAW, POLAND : 1960) 1986; 41:417-9. [PMID: 3755239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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42
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[Incidence of genetically determined hemorrhagic diathesis in Lower Silesia]. POLSKI TYGODNIK LEKARSKI (WARSAW, POLAND : 1960) 1986; 41:234-8. [PMID: 3714564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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43
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[Kaposi's sarcoma and acquired immunodeficiency syndrome (AIDS)]. POLSKI TYGODNIK LEKARSKI (WARSAW, POLAND : 1960) 1985; 40:1109-11. [PMID: 3909125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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44
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[Sedimentation leukapheresis in the treatment of resistant forms of lymphocytic leukemia]. POLSKI TYGODNIK LEKARSKI (WARSAW, POLAND : 1960) 1985; 40:561-3. [PMID: 4022828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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45
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[Sedimentation plasmapheresis in the treatment of multiple myeloma]. POLSKIE ARCHIWUM MEDYCYNY WEWNETRZNEJ 1985; 73:177-80. [PMID: 4047957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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46
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[Basophilic myelocytic leukemia]. POLSKIE ARCHIWUM MEDYCYNY WEWNETRZNEJ 1985; 73:45-8. [PMID: 3860799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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47
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[Development of malignant lymphoma during anticonvulsant therapy]. POLSKI TYGODNIK LEKARSKI (WARSAW, POLAND : 1960) 1983; 38:505-7. [PMID: 6634496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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48
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[Plasmacytic leukemia in non-secreting multiple myeloma]. POLSKI TYGODNIK LEKARSKI (WARSAW, POLAND : 1960) 1983; 38:179-80. [PMID: 6856511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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49
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[Rare histological picture of histiocytosis located in the cervical lymph nodes]. POLSKI TYGODNIK LEKARSKI (WARSAW, POLAND : 1960) 1981; 36:1105-6. [PMID: 7312683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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50
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[Clinical pattern, biochemical changes and prognostic factors in multiple myeloma]. POLSKIE ARCHIWUM MEDYCYNY WEWNETRZNEJ 1981; 65:11-6. [PMID: 6794008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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