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排序方式: 共有1518条查询结果,搜索用时 15 毫秒
1.
P Sacerdote F Rubboli L Locatelli I Ciciliato P Mantegazza A E Panerai 《Journal of neuroimmunology》1991,32(1):35-41
The concentrations of beta-endorphin and cholecystokinin were measured in fresh resting peripheral mononuclear cells obtained from rats and human subjects in basal conditions and after different pharmacological treatments. Both in the human and the rat, beta-endorphin concentrations in mononuclear cells, increased after treatment with serotoninergic agonists, decreased after dopaminergic or GABAergic drugs, while the respective antagonists exerted the opposite effect. In vitro, serotoninergic and GABAergic compounds confirmed their roles in the modulation of beta-endorphin in mononuclear cells. Cholecystokinin was never affected by the pharmacological treatments. 相似文献
2.
Nutritional-inflammation status and resistance to erythropoietin therapy in haemodialysis patients. 总被引:1,自引:0,他引:1
Francesco Locatelli Simeone Andrulli Bruno Memoli Camilla Maffei Lucia Del Vecchio Stefano Aterini Walter De Simone Antonella Mandalari Giuliano Brunori Marcello Amato Bruno Cianciaruso Carmine Zoccali 《Nephrology, dialysis, transplantation》2006,21(4):991-998
BACKGROUND: Chronic kidney disease patients who are resistant to erythropoietin (EPO) treatment may suffer from malnutrition and/or inflammation. METHODS: In a cross-sectional study of haemodialysis patients, we investigated the relationship between the natural logarithm of the weekly EPO dose normalized for post-dialysis body weight and outcome measures of nutrition and/or inflammation [BMI, albumin and C reactive protein (CRP)] by means of multiple linear regression analysis. On the basis of the decile distribution of weekly EPO doses, we also evaluated four groups of patients: untreated, hyper-responders, normo-responders and hypo-responders. RESULTS: Six hundred and seventy-seven adult haemodialysis patients were recruited from five Italian centres. BMI and albumin were lower in the hypo-responders than in the other groups (21.3+/-3.8 vs 24.4+/-4.7 kg/m(2), P<0.001; and 3.8+/-0.6 vs 4.1+/-0.4 g/dl, P<0.001), whereas the median CRP level was higher (1.9 vs 0.8 mg/dl, P = 0.004). The median weekly EPO dose ranged from 30 IU/kg/week in the hyper-responsive group to 263 IU/kg/week in the hypo-responsive group. Transferrin saturation linearly decreased from the hyper- to hypo-responsive group (37+/-15 to 25+/-10%, P = 0.003), without any differences in transferrin levels. Ferritin levels were lower in the hypo-responsive than in the other patients (median 318 vs 445 ng/ml, P = 0.01). At multiple linear regression analysis, haemoglobin, BMI, albumin, CRP and serum iron levels were independently associated with the natural logarithm of the weekly EPO dose (R(2) = 0.22). CONCLUSIONS: Our findings support a clear association between EPO responsiveness and nutritional and inflammation variables in haemodialysis patients; iron deficiency is still a major cause of hypo-responsiveness. 相似文献
3.
Maria Cristina Locatelli Lucilla Tedeschi Maurizia Clerici Antonella Romanelli Adelaide D'Antona Roberto Labianca Gino Luporini 《Supportive care in cancer》1996,4(3):218-219
We have reviewed the incidence of cisplatin-induced anaemia in patients affected with solid tumours treated with at least three courses of first-line cisplatincontaining regimens. In our experience, a low percentage (5%) of patients required transfusions of red blood cells. We think it is of the utmost importance to adopt uniform criteria in monitoring and treatment of patients at risk of developing cisplatin anaemia and to identify subsets of patients to eventually treat with erythropoietin. 相似文献
4.
A Andreani M Rambaldi A Locatelli A Fraccari R Bossa I Galatulas 《Pharmaceutica acta Helvetiae》1992,67(8):234-236
The synthesis of phenothiazine and anthraquinone derivatives, bearing at least one fragment present in lotifazole, is reported. Some of the new compounds showed antitumor activity in vitro (P388 leukemia cells) and in vivo (Ehrlich ascites tumor cells in mice). 相似文献
5.
6.
Vincenzo La Milia Salvatore Di Filippo Monica Crepaldi Simeone Andrulli Lucia Del Vecchio Pietro Scaravilli Giovambattista Virga Francesco Locatelli 《Nephrology, dialysis, transplantation》2004,19(7):1849-1855
BACKGROUND: Sodium removal (NaR) may have a major impact on the survival of peritoneal dialysis patients. The dialysate/plasma sodium concentration ratio (D/P(Na)) is an indirect index of transcellular water transport by aquaporin channels, and thus of ultrafiltration. Sodium concentration can be assessed by means of flame photometry (F), and direct (D-ISE) or indirect ion-selective electrodes (I-ISE), but these methods have different properties. I-ISE is being used increasingly in clinical laboratories. The aim of this study was to evaluate NaR and D/P(Na) using the three different measurement methods. METHODS: We performed peritoneal equilibration tests (PETs) in 44 peritoneal dialysis patients and calculated the NaR. We also calculated D/P(Na) during the test; plasma and dialysate sodium concentrations were measured by F, D-ISE and I-ISE. RESULTS: NaR was lower (P<0.001) with D-ISE (69+/-29 mmol) than with F (81+/-29 mmol) or I-ISE (79+/-28 mmol). D/P(Na) was also lower at baseline (0.92+/-0.02 vs 0.95+/-0.02 and 0.95+/-0.02; P<0.001), after 60 min (0.87+/-0.03 vs 0.90+/-0.03 and 0.90+/-0.03; P<0.001) and at the end of PET (0.88+/-0.04 vs 0.92+/-0.04 and 0.92+/-0.04; P<0.001) when measured by D-ISE in comparison with F and I-ISE, respectively. CONCLUSIONS: NaR and D/P(Na) were lower when measured by the D-ISE method compared with the F and I-ISE methods. NaR and D/P(Na) were similar when measured by F or I-ISE. I-ISE can be used reliably in the evaluation of NaR and D/P(Na) in everyday clinical practice of peritoneal dialysis. 相似文献
7.
A simple, rapid, and sensitive method for the determination of aspirin and salicylic acid in plasma of uremic patients is reported. After extraction with hexane, aspirin (ASA) and salicylic acid (SA) were quantified by high-performance liquid chromatography (HPLC) with ultraviolet detection at 229 nm. ASA and SA concentrations and peak-height ratios were linearly related up to 20 micrograms/ml. The lower limit of sensitivity was 0.1 microgram/ml for both compounds. The average recoveries of aspirin and salicylic acid were 27 and 54%, respectively. This procedure offers better performance than do previously described methods. The sample clean-up allows quantitation of a low concentration of aspirin in uremic patients' plasma, commonly rich in interfering endogenous substances. 相似文献
8.
The nonstructural protein 3 (NS3) of Dengue virus (DV) is a multifunctional enzyme carrying activities involved in viral RNA replication and capping: helicase, nucleoside 5'-triphosphatase (NTPase), and RNA 5'-triphosphatase (RTPase). Here, a 54-kDa C-terminal domain of NS3 (DeltaNS3) bearing all three activities was expressed as a recombinant protein. Structure-based sequence analysis in comparison with Hepatitis C virus (HCV) helicase indicates the presence of a HCV-helicase-like catalytic core domain in the N-terminal part of DeltaNS3, whereas the C-terminal part seems to be different. In this report, we show that the RTPase activity of DeltaNS3 is Mg2+-dependent as are both helicase and NTPase activities. Mutational analysis shows that the RTPase activity requires an intact NTPase/helicase Walker B motif in the helicase core, consistent with the fact that such motifs are involved in the coordination of Mg2+. The R513A substitution in the C-terminal domain of DeltaNS3 abrogates helicase activity and strongly diminishes RTPase activity, indicating that both activities are functionally coupled. DV RTPase seems to belong to a new class of Mg2+-dependent RTPases, which use the active center of the helicase/NTPase catalytic core in conjunction with elements in the C-terminal domain. 相似文献
9.
Incoronata Tritto Maria Carmela Sacchi Paolo Locatelli 《Macromolecular chemistry and physics.》1986,187(9):2145-2151
A 13C NMR analysis of the methyl and ethyl end-groups in isotactic polypropylene, prepared in the presence of TiCl3- and Til3-based catalysts, was performed and the isotactic regularity of the first propylene unit added to the Ti—alkyl bond was measured. In the presence of the catalyst Til3/Al(13CH2CH3)3 the stereoregulating effects derived from the ethyl and iodine ligands are cooperative, so that the addition of the first monomeric unit is as isotactic as the following propagation steps. A comparison of the chain end-groups of polypropylene obtained in the presence of different catalysts shows that the extent of steric control upon insertion of the first monomer molecule results not only from the presence of alkyl titanium ligands larger than methyl and of titanium halide ligands larger than chlorine, but also from mutual ligand interactions. 相似文献
10.
Incoronata Tritto San Xi Li Laura Boggioni Maria Carmela Sacchi Paolo Locatelli Aideen O'Neill 《Macromolecular chemistry and physics.》1997,198(5):1347-1361
Ethylene polymerizations and norbornene oligomerizations catalysed by Cp2Ti13CH3Cl/MAO (Cp: cyclopentadienyl; MAO: methylaluminoxane) mixtures have been carried out at different temperatures (from -20°C to 20°C), in order to test the validity of carbene mechanisms in α-olefin polymerizations. Depending on the temperature, different ratios of the cationic species [Cp2Ti13CH3]+[Cl · MAO]? and precursors of the alkylidene Cp2Ti = 13CH2 exist. The in situ polymerization of 13C enriched ethylene was monitored by 13C NMR spectroscopy. Moreover, catalytic activity was determined and polyethylene samples were analyzed by 13C NMR and gel permeation chromatography (GPC). The following evidence has been provided against the carbene mechanism in the α-olefin polymerization with titanocene based catalysts: (a) in the in situ ethylene polymerization experiments the appearance of polyethylene signals is concurrent with the decrease of cationic [Cp2Ti13CH3]+[Cl · MAO]? signals and is not related to the intensity of the alkylidene Cp2Ti = 13CH2 signals; (b) from the 13C NMR analysis of polyethylene chain-end groups the 13C enrichment of Cp2Ti13CH3Cl has only been found in the methyl chain-end group and not in the methylene of the propyl chain-end group, as should have been the case if the carbene mechanism had been valid; (c) from norbornene oligomerization (at 0°C) the addition product 2-13C enriched methyl-norbornane has been identified. Moreover, the identification of a 13C enriched methylidene-norbornane dimer at higher temperatures has revealed the possibility of norbornene addition to titanium carbenes through the formation of titanacyclobutane without the opening of the norbornene ring. However, this process requires higher energies with respect to the Cossee type insertion. 相似文献