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See detailIntrinsic vulnerability maps of a karstic aquifer as obtained by five different assessment techniques: comparison and comments
Gogu, Radu Constantin; Dassargues, Alain ULg

in Mudry, J.; Zwahlen, Fr. (Eds.) Proceedings of the 7th Conf. on Limestone Hydrology and Fissured Media - Sciences et Techniques de l'Environnement (2001)

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See detailAdministration of erythopoietin and granulocyte colony-stimulating factor in donor/recipient pairs to collect peripheral blood progenitor cells (PBPC) and red blood cell units for use in the recipient after allogeneic PBPC transplantation.
Sautois, Brieuc ULg; Baudoux, Etienne ULg; Salmon, Jean ULg et al

in Haematologica (2001), 86(11), 1209-18

BACKGROUND AND OBJECTIVES: It may be useful to reduce the exposure of transplant recipients to homologous blood. This may be achieved by procuring donor-derived red blood cell (RBC) units, collecting more ... [more ▼]

BACKGROUND AND OBJECTIVES: It may be useful to reduce the exposure of transplant recipients to homologous blood. This may be achieved by procuring donor-derived red blood cell (RBC) units, collecting more peripheral blood progenitor cells (PBPC) with a combination of granulocyte colony-stimulating factor (G-CSF) + recombinant human erythropoietin (rHuEpo) and by administering rHuEpo post-transplantation. DESIGN AND METHODS: Eight ABO-compatible donors were treated with rHuEpo and intravenous iron to collect 12 RBC units for use in their recipients. PBPC were collected after mobilization with rHuEpo and G-CSF in the same donors. The recipients received G-CSF and rHuEpo post-transplantation. A control group of 10 donor/recipient pairs received G-CSF alone for PBPC mobilization and after the transplantation. RESULTS: Eighty-six out of 91 planned RBC units were collected in the donors without significant decrease in hematocrit because of a 4-fold increase in RBC production despite functional iron deficiency. After 2 leukaphereses, the cumulative yields of NC and CFU-GM were lower in the study group while those of BFU-E, CFU-Mix and CD34+ cells were similar. However, erythroid recovery was significantly accelerated in the study group. INTERPRETATION AND CONCLUSIONS: Collection of 12 RBC units within 6 weeks is feasible with rHuEpo and intravenous iron; this strategy allows a dramatic reduction in recipient exposure to homologous blood; rHuEpo has no synergistic effect with G-CSF for mobilization of PBPC in normal donors and may even be deleterious; and rHuEpo in the recipient may enhance erythroid engraftment. [less ▲]

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See detailSerum soluble transferrin receptor concentration is an accurate estimate of the mass of tissue receptors.
R'Zik, Samir ULg; Beguin, Yves ULg

in Experimental hematology (2001), 29(6), 677-85

OBJECTIVE: Serum levels of the soluble transferrin receptor (sTfR) vary depending on the erythropoietic activity and iron status. In vitro, sTfR shed in the incubation medium correlates well with cellular ... [more ▼]

OBJECTIVE: Serum levels of the soluble transferrin receptor (sTfR) vary depending on the erythropoietic activity and iron status. In vitro, sTfR shed in the incubation medium correlates well with cellular TfR, but this relationship has never been established in vivo. To determine the value of serum sTfR as a quantitative marker of the body mass of tissue TfR, we designed experiments to examine the correlation between serum sTfR and tissue TfR in rats with various degrees of erythropoietic activity or iron status. MATERIALS AND METHODS: We studied changes in erythropoietic activity in normal rats as well as in animals experiencing hemolysis, phlebotomy-induced iron deficiency, transfusion- or thiamphenicol-induced erythroid aplasia, or inflammation. At the end of follow-up, ferrokinetic studies were performed and animals were sacrificed. Organs were isolated and homogenized to determine the total mass of tissue TfR from the sum of tissue solubilized TfR in the bone marrow, spleen, liver, and blood cells (direct method). An indirect method was developed to derive the corporeal mass of tissue TfR from a representative marrow sample. RESULTS: As expected, serum sTfR and total mass of tissue TfR varied as a function of iron status and erythropoiesis. Relative erythroid expansion in the spleen was greater than in the bone marrow. With the exception of phlebotomized animals, the indirect method correlated very well with direct measurements of the total mass of tissue TfR (r = 0.97, p < 0.0001). There was a close relationship between the total mass of tissue TfR and the total mass of serum sTfR (r = 0.79, p < 0.0001). Serum sTfR represented approximately 5-6% of the total mass of tissue TfR in most experimental situations, but this ratio was twice as high during iron-restricted erythropoiesis. In addition, the ratio could be higher or lower in nonsteady-state situations, because changes in tissue TfR occurred faster than those of serum sTfR. CONCLUSIONS: Serum sTfR represents a constant proportion of the total mass of tissue TfR over a wide range of erythropoietic activity. However, iron deficiency results in a higher proportion of serum sTfR, and the pace of change in serum sTfR levels is slower than that of tissue TfR mass. [less ▲]

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See detailReticulocyte transferrin receptor (TfR) expression and contribution to soluble TfR levels.
R'Zik, Samir ULg; Loo, Martine; Beguin, Yves ULg

in Haematologica (2001), 86(3), 244-51

BACKGROUND AND OBJECTIVES: Transferrin receptor (TfR) expression in erythroid cells is regulated by a number of factors, including iron status and erythropoietin (Epo) stimulation. However, the impact of ... [more ▼]

BACKGROUND AND OBJECTIVES: Transferrin receptor (TfR) expression in erythroid cells is regulated by a number of factors, including iron status and erythropoietin (Epo) stimulation. However, the impact of these factors on reticulocyte TfR expression in vivo has never been studied. A soluble form of TfR (sTfR) is present in serum in proportion to the mass of cellular TfR. Although sTfR shedding by reticulocytes and erythroblasts has been demonstrated in vitro, the contribution of reticulocyte TfR to serum sTfR has never been evaluated in vivo. DESIGN AND METHODS: We measured directly the total number of reticulocyte TfR in normal rats of different age and iron status, as well as in animals experiencing various conditions and treatments aimed at altering erythropoietic activity and iron status, including rHuEpo therapy, hemolytic anemia, phlebotomies, hypertransfusions, thiamphenicol-induced red cell aplasia or inflammation. In addition, we examined the impact of repeated hypertransfusions with normal, reticulocyte-poor and reticulocyte-rich blood on serum sTfR levels. RESULTS: The number of TfR molecules per reticulocyte was around 50,000 in young rats but was around 100,000 in older animals. These values remained constant in most conditions and in particular were not influenced by iron supplementation or iron overload. However, functional iron deficiency as well as rHuEpo therapy resulted in increased reticulocyte TfR expression. In addition, TfR numbers in reticulocytes were elevated in the early phase of recovery after acute hemolysis or red cell aplasia but normalized soon after. Hypertransfusion experiments clearly demonstrated that reticulocytes can contribute substantially to sTfR levels in vivo. INTERPRETATION AND CONCLUSIONS: TfR numbers are regulated in vivo by the same factors as in vitro, in particular iron deficiency and erythropoietin stimulation. Circulating reticulocytes contribute significantly to serum sTfR levels. [less ▲]

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See detailExpression of Cu/Zn and Mn superoxide dismutases during bovine embryo development: influence of in vitro culture.
Lequarré, Anne-Sophie ULg; Feugang, Jean-Magloire; Malhomme, Olivier et al

in Molecular Reproduction and Development (2001), 58(1), 45-53

Temporal pattern of expression of Cu/Zn and Mn superoxide dismutases (SODs) was investigated in bovine oocytes and embryos produced in vitro in two different culture conditions and in vivo after ... [more ▼]

Temporal pattern of expression of Cu/Zn and Mn superoxide dismutases (SODs) was investigated in bovine oocytes and embryos produced in vitro in two different culture conditions and in vivo after superovulation. SODs were examined at a transcriptional level in single oocytes and embryos by reverse transcriptase-polymerase chain reaction (RT-PCR) and, at a protein level, by Western blotting on pools of embryos. mRNA encoding Cu/Zn SOD were detected in in vitro bovine embryos throughout preattachment development as well as in in vivo derived morulae and blastocysts. Transcripts for Mn SOD gene were detected in most immature and in vitro matured oocytes as well as in some zygotes and 5- to 8-cell embryos while no transcript was found at the 9-to 16-cell stage in both culture conditions. In vitro embryonic expression of Mn SOD was detected earlier in the presence of serum. Half of the morulae showed the transcript if cultured with 5% serum while none without serum. At the blastocyst stage Mn SOD could be detected independently of culture conditions. For in vivo-derived embryos Mn SOD transcripts were detected both in morulae and blastocysts. Immunoblotting analyses revealed that Cu/Zn SOD and Mn SOD were also present at a protein level in in vitro-derived zygotes and blastocysts. Together these data demonstrate, for the first time, that Mn SOD is transcribed and that Cu/Zn and Mn SOD proteins are expressed in preimplantation bovine embryos. Finally, they suggest that Mn SOD transcription is altered by in vitro culture conditions. [less ▲]

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See detailIpNose : Electronic nose for remote bad odour monitoring system in landfill sites.
Perera, A.; Pardo, T.; Sundi, T. et al

in Proceedings of the 8th conference Eurodeur (2001)

Electronic noses are intelligent instruments that are able to classify and quantify different gas/odours. Here we suggest the integration of a small form factor computer inside the electronic nose. This ... [more ▼]

Electronic noses are intelligent instruments that are able to classify and quantify different gas/odours. Here we suggest the integration of a small form factor computer inside the electronic nose. This concept allows us to easily provide remote connectivity, large data storage and complex signal processing. The evolution of this technology will permit distributed sensing with applications to agriculture and environment. Proposed instrument allows incoming connections for remote control of bad odours in landfill sites. Preliminary approach to this application using commercial sensors and mixture model pattern recognition scheme is exposed. [less ▲]

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See detailTraçabilité dans la filière viande. I. La traçabilité administrative.
Evrard, V.; China, B.; Noirfalise, R. et al

in Annales de Médecine Vétérinaire (2001), 145

Le secteur de la viande a été secoué ces dernières années par quelques scandales, tels ceux des hormones et de la dioxine, avec pour conséquences une perte de confiance de la part du consommateur et une ... [more ▼]

Le secteur de la viande a été secoué ces dernières années par quelques scandales, tels ceux des hormones et de la dioxine, avec pour conséquences une perte de confiance de la part du consommateur et une perturbation du marché de la viande. Pour redresser l’image des produits carnés belges, il est important de pouvoir en déterminer et en garantir l’origine. En Belgique, il existe divers systèmes de traçabilité administrative dont le principal est le système SANITEL qui comprend un système automatisé de traitement de données relatives à l’identification et l’enregistrement des animaux. Au-delà de l’aspect légal et réglementaire, différentes initiatives, visant une amélioration de la qualité, fleurissent : "les labels". Ceux-ci intègrent fréquemment la traçabilité dans leur cahier des charges. La traçabilité administrative n’est pas infaillible, la perte de documents et les fraudes peuvent ternir l’image de celle-ci. C’est pourquoi le système documentaire a été associé aux empreintes génétiques des animaux. 5 [less ▲]

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See detailTraçabilité dans la filière viande. 2. Les marqueurs génétiques.
China, B.; Evrard, V.; Noirfalise, R. et al

in Annales de Médecine Vétérinaire (2001), 145

Afin d’assurer une transparence tout le long de la chaîne de transformation de la viande, il faut disposer d’un système de traçabilité performant. La traçabilité administative montre des limites que ... [more ▼]

Afin d’assurer une transparence tout le long de la chaîne de transformation de la viande, il faut disposer d’un système de traçabilité performant. La traçabilité administative montre des limites que l’utilisation de marqueurs génétiques pourrait surmonter. Le génome de chaque individu possède des différences de séquences, à la base du polymorphisme génétique, dont les marqueurs génétiques sont les témoins. Parmi ceux-ci, deux classes semblent s’imposer en matière de traçabilité : les microsatellites et les polymorphismes simple nucléotide. Les microsatellites sont caractérisés par un degré de polymorphisme important avec de nombreux allèles pour un même locus. De plus, leur détection se fait directement par amplification itérative. Techniquement, le problème se pose lors de la détection simultanée de plusieurs microsatellites où le patron obtenu est difficile à interpréter. Les polymorphismes simple nucléotide sont répresentés par des mutations ponctuelles dans la séquence nucléotidique. Ils sont fréquents, stables, répartis de façon aléatoire et généralement bialléliques. La détection se fait soit par hybridation sur des biopuces, soit par spectrométrie de masse ou par d’autres techniques facilement automatisables. Cette automatisation est nécessaire pour pouvoir tester un grand nombre de polymorphismes simultanément sur un grand nombre d’échantillons, permettant ainsi de diminuer les coûts. L’avantage majeur des polymophismes simple nucléotide est le signal binaire obtenu, son désavantage est le caractère population- spécifique de ce type de marqueur. [less ▲]

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See detailIsolation of Clostridium perfringens from three neonatal calves with haemorrhagic abomasitis.
Manteca, C.; Jauniaux, Thierry ULg; Daube, Georges ULg et al

in Revue de Médecine Vétérinaire (2001), 152

Braxy-like disease with sudden death and acute haemorhagic abomasitis was diagnosed in three Belgian Blue calves : one two-day-old and one one month-old calves, in good condition with no clinical signs ... [more ▼]

Braxy-like disease with sudden death and acute haemorhagic abomasitis was diagnosed in three Belgian Blue calves : one two-day-old and one one month-old calves, in good condition with no clinical signs noted a few hours prior to death, and another two day-old calf, which had shown problems of abomasal dilatation and regurgitation prior to death. Histologically, the abomasal wall were oedematous and emphysematous. A pure and abundant growth of Clostridium perfringens was obtained in anaerobic conditions from the abomasal wall of the three Belgian Blue calves. No bacterial growth was obtained in aerobic conditions. The calf with digestive disorders was also positive for BVD virus by immunofluorescence in the abomasal wall and in the spleen. [less ▲]

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See detailClonage humain et processus de prise de décision publique
Brunet, Sébastien ULg

Conference given outside the academic context (2001)

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See detailImage analysis, impedance spectroscopy and mercury porosimetry characterisation of freeze-drying porous materials
Blacher, Silvia ULg; Maquet, Véronique; Pirard, René ULg et al

in Colloids and Surfaces A : Physicochemical and Engineering Aspects (2001), 187-188

Image analysis and impedance spectroscopy have been used as potential tools for the characterization of the texture of ultramacroporous PLA foams prepared by freeze-drying. It has been shown that these ... [more ▼]

Image analysis and impedance spectroscopy have been used as potential tools for the characterization of the texture of ultramacroporous PLA foams prepared by freeze-drying. It has been shown that these two techniques actually provide valuable information on the structure of this material. They are complementary to mercury porosimetry, which does not allow morphological details to be distinguished. Image analysis of SEM micrographs of transverse cross-sections at two different magnifications gave information on both the macroporosity (1 μm < width < 10 μm) and ultramacroporosity (width > 10 μm). Impedance spectroscopy was used to investigate the transport properties of the three-dimensional porous matrices by measurement of ionic conduction [less ▲]

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See detailModule checking
Kupferman, Orna; Vardi, Moshe Y; Wolper, Pierre ULg

in Information & Computation (2001), 164(2), 322-344

In computer system design, we distinguish between closed and open systems. A closed system is a system whose behavior is completely determined by the state of the system. An open system is a system that ... [more ▼]

In computer system design, we distinguish between closed and open systems. A closed system is a system whose behavior is completely determined by the state of the system. An open system is a system that interacts with its environment and whose behavior depends on this interaction. The ability of temporal logics to describe an ongoing interaction of a reactive program with its environment makes them particularly appropriate for the specification of open systems. Nevertheless, model-checking algorithms used for the verification of closed systems are not appropriate for the verification of open systems. Correct model checking of open systems should check the system with respect to arbitrary environments and should take into account uncertainty regarding the environment. This is not the case with current model-checking algorithms and tools. In this paper we introduce and examine the problem of model checking of open systems (module checking, for short). We show that while module checking and model checking coincide for the linear-time paradigm, module checking is much harder than model checking for the branching-time paradigm. We prove that the problem of module checking is EXPTIME-complete for specifications in CTL and 2EXPTIME-complete for specifications in CTL*. This bad news is also carried over when we consider the program-complexity of module checking. As good news, we show that for the commonly-used fragment of CTL (universal, possibly, and always possibly properties), current model-checking tools do work correctly, or can be easily adjusted to work correctly, with respect to both closed and open systems. (C) 2001 Academic Press. [less ▲]

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See detailHST and ground-based observations of the gravitational lens system Q1009-0252 A & B
Claeskens, Jean-François ULg; Khmil, S. V.; Lee, Dong Wook et al

in Astronomy and Astrophysics (2001), 367

In this paper, we propose a critical study of direct images and spectra obtained for the doubly imaged QSO Q1009-0252 A & B (=LBQS1009-0252 A & B). First, we report new observations with the WFPC2 onboard ... [more ▼]

In this paper, we propose a critical study of direct images and spectra obtained for the doubly imaged QSO Q1009-0252 A & B (=LBQS1009-0252 A & B). First, we report new observations with the WFPC2 onboard the Hubble Space Telescope (HST), in which the lensing galaxy is very clearly detected. We combine these with existing NICMOS observations in order to characterize the nature and redshift of the lens. Our HST observations are also fitted with simple analytical lens models; estimates expected for the time delay and M/L of the lensing galaxy are derived. Secondly, new and existing ground-based observations are used in order to establish the first multicolour lightcurves of the lensed components. Although the time resolution is low, flux variability is detected for both components. Finally, ground-based spectroscopic observations published by Surdej et al. (1993) are re-processed with a new method designed to extract spectra with small angular separations. The final spectra are analysed on the basis of a simple model including macrolensing and microlensing amplifications and dust extinction. Based on observations collected at the European Southern Observatory (La Silla, Chile) and with the Hubble Space Telescope. [less ▲]

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See detailQuasar pairs with arcminute angular separations
Zhdanov, V. I.; Surdej, Jean ULg

in Astronomy and Astrophysics (2001), 372

We use the Véron-Cetty & Véron (\cite {veron}) catalog (VV) of 13 213 quasars to investigate their possible physical grouping over angular scales 10arcsec <=Delta theta <= 1000arcsec . We first estimate ... [more ▼]

We use the Véron-Cetty & Véron (\cite {veron}) catalog (VV) of 13 213 quasars to investigate their possible physical grouping over angular scales 10arcsec <=Delta theta <= 1000arcsec . We first estimate the number of quasar pairs that would be expected in VV assuming a random distribution for the quasar positions and taking into account observational selection effects affecting heterogeneous catalogs. We find in VV a statistically significant (>3sigma ) excess of pairs of quasars with similar redshifts (Delta z<= 0.01) and angular separations in the 50arcsec -100arcsec range, corresponding to projected linear separations (0.2-0.5) Mpc/h[SUB]75[/SUB] (Omega[SUB]M[/SUB] =1, Omega[SUB]Lambda[/SUB] =0) or (0.4-0.7) Mpc/h[SUB]75[/SUB] (Omega[SUB]M[/SUB] =0.3, Omega[SUB]Lambda[/SUB] = 0.7). There is also some excess in the 100arcsec -600arcsec range corresponding to (1-5) Mpc in projected linear separations. If most of these quasar pairs do indeed belong to large physical entities, these separations must represent the inner scales of huge mass concentrations (cf. galaxy clusters or superclusters) at high redshifts; but it is not excluded that some of the pairs may actually consist of multiple quasar images produced by gravitational lensing. Of course, a fraction of these pairs could also arise due to random projections of quasars on the sky. The list of 11 pairs of quasars with redshift differences Delta z<= 0.02 and angular separations 50arcsec <= Delta theta <= 100arcsec is presented in order to stimulate further observational studies and to better understand the astrophysical and cosmological significance of these interesting objects. [less ▲]

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See detailObligations des parties et sanctions des obligations dans la Convention de Vienne
Wautelet, Patrick ULg; van Houtte, Hans

in Revue du droit des affaires internationales - International Business Law Journal (2001)

This paper provides a detailed overview of the rights and duties of both seller and buyer under the Vienna Sales Convention. It does so in the light not only of the text of the Convention but also of the ... [more ▼]

This paper provides a detailed overview of the rights and duties of both seller and buyer under the Vienna Sales Convention. It does so in the light not only of the text of the Convention but also of the emerging case law of various countries, which is reviewed and taken into account. The overview also attempts to contrast the rules of the Convention with the rules applicable in Belgian contract law. [less ▲]

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See detailLa sensibilisation du personnel dans le cadre de la mise en place d'un système de management environnemental : une porte d'entrée pour l'éducation relative à l'environnement dans l'entreprise ?
Domasik, Marie-Claire ULg; Semal, Nathalie ULg; Von Frenckell, Marianne ULg

in Education relative à l'environnement- Regards, recherches, réflexions (2001), 3

The increasing needs of enterprises in environmental training, in relation with the rise in environmental management systems in Belgium, generate new research needs in environmental education (EE) scope ... [more ▼]

The increasing needs of enterprises in environmental training, in relation with the rise in environmental management systems in Belgium, generate new research needs in environmental education (EE) scope. The authors experience shows that the entreprises’ expectations can meet EE objectives, and that environmental awareness programs for corporate employees can enable them to adapt their professionnal and private behaviour. This efficiency is based on interactive designing of training actions, responsability sharing and mutual learning. However, EE efficiency in enterprises depends on corporate culture and its capacity to evolve. [less ▲]

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See detailMagnetotransport properties of a single grain boundary in a bulk La-Ca-Mn-O material
Vertruyen, Bénédicte ULg; Cloots, Rudi ULg; Rulmont, André ULg et al

in Journal of Applied Physics (2001), 90(11), 5692-5697

Besides the "intrinsic" colossal magnetoresistance effect observed in single crystals, the polycrystalline manganate compounds also exhibit an "extrinsic" magnetoresistance related to the presence of ... [more ▼]

Besides the "intrinsic" colossal magnetoresistance effect observed in single crystals, the polycrystalline manganate compounds also exhibit an "extrinsic" magnetoresistance related to the presence of grain boundaries. We report electrical transport and magnetic measurements carried out on a bigrain sample extracted from a floating zone method-grown rod of calcium doped lanthanum manganate. Electrical resistance was measured both within a grain and across the grain boundary, between 20 and 300 K and from 0 to 8 T. Magnetoresistance values up to 99% are reached within the grain. The temperature dependence of the resistance across the grain boundary displays a "foot-like" feature towards the bottom of the transition. Low field and high field magnetoresistance effects are examined. We compare our results for a "bulk" grain boundary to those obtained by other authors for bicrystal thin films and bulk polycrystalline materials. (C) 2001 American Institute of Physics. [less ▲]

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See detailOutcome is not improved by the use of alternating chemotherapy in elderly patients with aggressive lymphoma
Bosly, André; Lepage, Eric; Coiffier, Bertrand et al

in Hematology Journal : The Official Journal of the European Haematology Association (2001), 2

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See detailIntraconzole versus amphotericin B plus nystatin in the prophylaxis of fungal infections in neutropenic cancer patients
Boogaerts, Marc; Maertens, Johan; van Hoof, Achiel et al

in Journal of Antimicrobial Chemotherapy (2001), 48

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