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排序方式: 共有6791条查询结果,搜索用时 15 毫秒
61.
Aránzazu Caballero-Marcos Magdalena Salcedo Roberto Alonso-Fernández Manuel Rodríguez-Perálvarez María Olmedo Javier Graus Morales Valentín Cuervas-Mons Alba Cachero Carmelo Loinaz-Segurola Mercedes Iñarrairaegui Lluís Castells Sonia Pascual Carmen Vinaixa-Aunés Rocío González-Grande Alejandra Otero Santiago Tomé Javier Tejedor-Tejada José María Álamo-Martínez Luisa González-Diéguez Flor Nogueras-Lopez Gerardo Blanco-Fernández Gema Muñoz-Bartolo Francisco Javier Bustamante Emilio Fábrega Mario Romero-Cristóbal Rosa Martin-Mateos Julia Del Rio-Izquierdo Ana Arias-Milla Laura Calatayud Alberto A. Marcacuzco-Quinto Víctor Fernández-Alonso Concepción Gómez-Gavara Jordi Colmenero Patricia Muñoz José A. Pons the Spanish Society of Liver Transplantation 《American journal of transplantation》2021,21(8):2876-2884
The protective capacity and duration of humoral immunity after SARS-CoV-2 infection are not yet understood in solid organ transplant recipients. A prospective multicenter study was performed to evaluate the persistence of anti-nucleocapsid IgG antibodies in liver transplant recipients 6 months after coronavirus disease 2019 (COVID-19) resolution. A total of 71 liver transplant recipients were matched with 71 immunocompetent controls by a propensity score including variables with a well-known prognostic impact in COVID-19. Paired case–control serological data were also available in 62 liver transplant patients and 62 controls at month 3 after COVID-19. Liver transplant recipients showed a lower incidence of anti-nucleocapsid IgG antibodies at 3 months (77.4% vs. 100%, p < .001) and at 6 months (63.4% vs. 90.1%, p < .001). Lower levels of antibodies were also observed in liver transplant patients at 3 (p = .001) and 6 months (p < .001) after COVID-19. In transplant patients, female gender (OR = 13.49, 95% CI: 2.17–83.8), a longer interval since transplantation (OR = 1.19, 95% CI: 1.03–1.36), and therapy with renin–angiotensin–aldosterone system inhibitors (OR = 7.11, 95% CI: 1.47–34.50) were independently associated with persistence of antibodies beyond 6 months after COVID-19. Therefore, as compared with immunocompetent patients, liver transplant recipients show a lower prevalence of anti-SARS-CoV-2 antibodies and more pronounced antibody levels decline. 相似文献
62.
Receptors for IgM were detected on peripheral blood human eosinophils by a rosette technique with ox red blood cells coated with the IgM fraction of the specific immunserum. Between 14 % and 43 % (mean 27 %) FcµR positive cells were found after an overnight incubation period at 37°C by using this technique. The specificity of the receptors for IgM was assessed by studying the inhibitory capacity of purified human IgM in the rosette assay. From an ultrastructural point of view, the EAM rosette-forming cells are mature eosinophlic granulocytes characterized by a nucleus with a variable number of lobes and a certain number of «first type» granules partially or totally devoid of their content. 相似文献
63.
Riccardo Patacchini Carlo Alberto Maggi Alberto Meli 《Naunyn-Schmiedeberg's archives of pharmacology》1990,342(1):72-77
Summary 1. The effects of some naturally occurring pungent substances, piperine, mustard oil, eugenol and curcumin, were compared to those of capsaicin in the rat isolated urinary bladder. 2. All test compounds dose-dependently contracted the rat bladder and produced desensitization toward capsaicin (1 mol/l). Development of cross-tachyphylaxis among the natural pungent substances on one hand and capsaicin on the other, suggested a common site of action on visceral primary afferents. 3. Contractile responses to piperine, mustard oil and eugenol were partially tetrodotoxin and ruthenium red-sensitive, suggesting that activation of sensory terminals by these agents takes place indirectly, as well as by a direct action on sensory receptors. 4. The presence of the secondary acylamide linkage (present in the backbone of capsaicin, but not in that of test compounds) does not appear to be essential to produce desensitization of sensory nerve terminals.
Send offprint requests to R. Patacchini at the above address 相似文献
64.
Pellegrini-Giampietro DE Cozzi A Peruginelli F Leonardi P Meli E Pellicciari R Moroni F 《The European journal of neuroscience》1999,11(10):3637-3647
Metabotropic glutamate (mGlu) receptors have been implicated in a number of physiological and pathological responses to glutamate, but the exact role of group I mGlu receptors in causing postischaemic injury is not yet clear. In this study, we examined whether the recently-characterized and relatively selective mGlu1 receptor antagonists 1-aminoindan-1,5-dicarboxylic acid (AIDA) and (S)-(+)-2-(3'-carboxybicyclo[1.1.1]pentyl)-glycine (CBPG) could reduce neuronal death in vitro, following oxygen-glucose deprivation (OGD) in murine cortical cell and rat organotypic hippocampal cultures, and in vivo, after global ischaemia in gerbils. When present in the incubation medium during the OGD insult and the subsequent 24 h recovery period, AIDA and CBPG significantly reduced neuronal death in vitro. The extent of protection was similar to that observed with the nonselective mGlu receptor antagonist (+)-alpha-methyl-4-carboxyphenylglycine [(+)MCPG] and with typical ionotropic glutamate (iGlu) receptor antagonists. Neuroprotection was also observed when AIDA or CBPG were added only after the OGD insult was terminated. Neuronal injury was not attenuated by the inactive isomer (-)MCPG, but was significantly enhanced by the nonselective mGlu receptor agonist (1S,3R)-1-aminocyclopentane-1, 3-dicarboxylic acid [(1S,3R)-ACPD] and the group I mGlu receptor agonist 3,5-dihydroxyphenylglycine (3,5-DHPG). The antagonists (+)MCPG, AIDA and CBPG were also neuroprotective in vivo, because i. c.v. administration reduced CA1 pyramidal cell degeneration examined 7 days following transient carotid occlusion in gerbils. Our results point to a role of mGlu1 receptors in the pathological mechanisms responsible for postischaemic neuronal death and propose a new target for neuroprotection. 相似文献
65.
Santiago JM 《Psychiatric services (Washington, D.C.)》1999,50(12):1571-1576
As the debate over managed care continues, measuring quality has increasingly become a focus in health care. One approach to measuring quality is the use of a scorecard, which summarizes a critical set of indicators that measure the quality of care. The author describes the Balanced Scorecard (BSC), a tool developed for use in businesses to implement strategic plans for meeting an organization's objectives, and shows how the BSC can be adapted for use in behavioral health care. The scorecard addresses quality of care at five levels: financial, customer, outcomes, internal processes, and learning and growth. No more than four or five realistic objectives are chosen at each level, and an indicator for the achievement of each objective is designed. The BSC integrates indicators at the five levels to help organizations guide implementation of strategic planning, report on critical outcomes, and offer a report card for payers and consumers to make informed choices. 相似文献
66.
Giuseppe Caliendo Ferdinando Fiorino Paolo Grieco Elisa Perissutti Vincenzo Santagada Rosaria Meli Giuseppina Mattace Raso Angelina Zanesco Gilberto De Nucci 《European journal of medicinal chemistry》1999,34(12):1043
Two sets of benzotriazinone and benzoyltriazole derivatives were prepared and tested for local anaesthetic activity in comparison with lidocaine. Several of the prepared compounds exhibited a fairly good activity comparable or superior to that of lidocaine. The presence of a benzotriazinone or a benzoyltriazole moiety as an aromatic system was quite profitable for both the intensity and duration of activity. The acute toxicity in mice of the four most potent compounds of the series was also assessed. Compound 1b, which has an anaesthetic activity comparable to that of lidocaine, was also characterized by a more favourable therapeutic index. All compounds were tested in vitro to evaluate their negative chronotropic action in isolated rat right atria. 相似文献
67.
Velmahos GC Chahwan S Falabella A Hanks SE Demetriades D 《World journal of surgery》2000,24(5):539-545
Angiographic embolization (AE) has been used extensively for bleeding control after injuries to the face and neck. Its role
in abdominal trauma requires further exploration. We reviewed the medical records of 137 consecutive patients who underwent
angiography with the intent to embolize bleeding sites within the abdomen. Of them, 97 (71%) had blunt and 40 (29%) had penetrating
trauma. AE was performed for hemorrhage associated with pelvic fractures (97 patients), liver lacerations (n= 26), renal lacerations (n= 12), splenic lacerations (n= 5), other injuries (n= 9), and multiple injuries (n= 12). On angiography, 102 patients were found to have bleeding sites and underwent AE, with angiographic and clinical bleeding
control in 93 (91%). The rate of successful hemostasis by AE was identical in blunt and penetrating trauma patients. There
was no major morbidity after AE. No factors predicted patients with a high likelihood to have a positive angiogram. Patients
who had AE before or after a period of attempted hemodynamic stabilization in the intensive care unit were no different with
respect to hemodynamic parameters immediately before AE or effectiveness of AE for bleeding control. AE is a safe and effective
method for controlling bleeding after blunt and penetrating intra- and retroperitoneal injuries. Early AE may be used in selected
patients as a front-line therapeutic intervention that offers expeditious hemostasis and prevents delays in definitive bleeding
control. 相似文献
68.
Brozzetti S Meli C Polistena A Musto F De Toma G Cavallaro A 《Il Giornale di chirurgia》2000,21(3):95-98
Multiple carcinoid tumors of the small bowel with more than 3 lesions are very unusual. The authors report a case with 4 lesions, 2 of those localized in the jejunum with more advanced infiltration of the wall and extension to regional mesenteric lymph nodes, revealed by ultrasonography. The relative low incidence and particularly the vague, nonspecific clinical presentation, the unusual site in the jejunum, and failure of the radiological examine of one year before lead to not suspect this condition prior to US examination. However, the feature of asymmetric, concentric thickening of the bowel wall requiring a more accurate exam by CT with oral contrast was able to confirm the suspect of the intestinal tumor. The patient, 80 year old, underwent radical surgery with a wide lymph nodes dissection as well as double resection of the jejunum and distal ileum. The post-surgical outcome was uneventful. A 12-month follow-up is free of the disease. 相似文献
69.
Lilia Suárez María-Belén Vidriales José García-Lara?a Guillermo Sanz María-José Moreno Antonio López Susana Barrena Rafael Martínez Mar Tormo Luis Palomera Esperanza Lavilla Ma Consuelo López-Berges María de Santiago M Encarnación Pérez de Equiza Jesús F San Miguel Alberto Orfao 《Clinical cancer research》2004,10(22):7599-7606
Myelodysplastic syndromes and acute myeloid leukemia (AML) are heterogeneous disorders in which conflicting results in apoptosis and multidrug resistance (MDR) have been reported. We have evaluated by multiparameter flow cytometry the expression of apoptosis- (APO2.7, bcl-2, and bax) and MDR-related proteins [P-glycoprotein (P-gp), multidrug resistance protein (MRP), and lung resistance protein (LRP)] specifically on bone marrow (BM) CD34+ cells, and their major CD32-/dim and CD32+ subsets, in de novo AML (n=90), high-risk myelodysplastic syndrome (n=9), and low-risk myelodysplastic syndrome (n=21) patients at diagnosis, and compared with normal BM CD34+ cells (n=6). CD34+ myeloid cells from AML and high-risk myelodysplastic syndrome patients displayed higher expression of bcl-2 (P <0.0001) and lower reactivity for APO2.7 (P=0.002) compared with low-risk myelodysplastic syndrome and normal controls. Similar results applied to the two predefined CD34+ myeloid cell subsets. No significant differences were found in the expression of P-gp, MRP, and LRP between low-risk myelodysplastic syndrome patients and normal BM, but decreased expression of MRP (P <0.03) in AML and high-risk myelodysplastic syndromes and P-gp (P=0.008) in high-risk myelodysplastic syndromes were detected. Hierarchical clustering analysis showed that low-risk myelodysplastic syndrome patients were clustered next to normal BM samples, whereas high-risk myelodysplastic syndromes were clustered together and mixed with the de novo AML patients. In summary, increased resistance to chemotherapy of CD34+ cells from both AML and high-risk myelodysplastic syndromes would be explained more appropriately in terms of an increased antiapoptotic phenotype rather than a MDR phenotype. In low-risk myelodysplastic syndromes abnormally high apoptotic rates would be restricted to the CD34- cell compartments. 相似文献
70.
Quantitative analysis of bcl-2 expression in normal and leukemic human B-cell differentiation. 总被引:5,自引:0,他引:5
P Menendez A Vargas C Bueno S Barrena J Almeida M De Santiago A López S Roa J F San Miguel A Orfao 《Leukemia》2004,18(3):491-498
Lack of apoptosis has been linked to prolonged survival of malignant B cells expressing bcl-2. The aim of the present study was to analyze the amount of bcl-2 protein expressed along normal human B-cell maturation and to establish the frequency of aberrant bcl-2 expression in B-cell malignancies. In normal bone marrow (n=11), bcl-2 expression obtained by quantitative multiparametric flow cytometry was highly variable: very low in both CD34(+) and CD34(-) B-cell precursors, high in mature B-lymphocytes and very high in plasma cells. Bcl-2 expression of mature B-lymphocytes from peripheral blood (n=10), spleen (n=8) and lymph node (n=5) was significantly higher (P<0.02) in CD23(-) as compared to CD23(+) B cells, independent of the type of tissue analyzed. Upon comparison with normal human B-cell maturation, bcl-2 expression in neoplastic B cells from 144 patients was found to be aberrant in 66% of the cases, usually corresponding to bcl-2 overexpression (63%). Follicular lymphoma (FL) carrying t(14;18) and MALT lymphoma were the only diagnostic groups constantly showing overexpression of bcl-2. Bcl-2 overexpression was also frequently found in precursor B-acute lymphoblastic leukemia (84%), typical (77%) and atypical (75%) B-cell chronic lymphocytic leukemia, prolymphocytic leukemia (two of three cases), mantle cell lymphoma (55%), but not in t(14;18)(-) FL, splenic marginal zone lymphoma, Burkitt lymphoma and multiple myeloma. 相似文献