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单克隆抗体博来霉素A6偶联物对白血病细胞特异性结合与内化 总被引:2,自引:0,他引:2
抗CCT2单克隆抗体博来霉素A6偶联物可吸附胶体金颗粒(McAb-A6-Au)。电镜观察表明,在4℃,1h,表面有McAb-A6-Au颗粒的CEM细胞最高达78%;在37℃,4h,内化McAb-A6-Au颗粒的CEM细胞高达72%。而抗原性无关的U937细胞仅为14%。并且McAb-A6-Au颗粒能直接穿过细胞膜、核膜进入细胞浆和细胞核。37℃,1h已有10~18%的CEM细胞核内有McAb-A 6-Au颗粒。实验结果提示了单抗与博来霉素A6的偶联物与选择性地结合靶细胞,而且进入细胞速度快、穿透力强,有可能成为治疗白血病药物。 相似文献
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The predictive value of soluble major histocompatibility complex class I chain-related molecule A (MICA) levels on heart allograft rejection 总被引:4,自引:0,他引:4
Suárez-Alvarez B López-Vázquez A Díaz-Molina B Bernardo-Rodríguez MJ Alvarez-López R Pascual D Astudillo A Martínez-Borra J Lambert JL González S López-Larrea C 《Transplantation》2006,82(3):354-361
BACKGROUND: Recently the presence of a soluble form of major histocompatibility complex class I chain-related molecule A (sMICA) has been detected in the sera of patients with tumors. Shedding of sMICA by tumor cells downregulates NKG2D-mediated antitumor immunity. The aim of this investigation was to study the possible involvement of sMICA in the allograft acceptance after heart transplantation (HTX). METHODS: We monitored the levels of sMICA by specific enzyme-linked immunosorbent assay (ELISA) in a total of 146 serum samples obtained from 34 heart transplantation patients followed up during the first year post-HTX. RESULTS: The persistence of sMICA expression was correlated with the clinical evolution of these patients. sMICA was detected in the serum of 21 of 34 patients (61.70%) between 15 and 20 days after implantation and was practically absent in pretransplant serum samples. Twenty of these 21 patients (95.24%) with sMICA did not experience episodes of severe rejection during this period (P = 0.0001), whereas sMICA was practically absent in patients with manifestations of severe acute rejection. The longitudinal study of these patients revealed that the presence of sMICA was consistently maintained in 75% of the patients with good graft status during the period of observation. CONCLUSION: This has led us to believe that the presence of levels of sMICA during the first year post-HTX may contribute to allograft acceptance. Additionally, functional studies indicate that sMICA downregulates NKG2D surface expression, which may lead to a functional impairment of cell-mediated cytolysis. These data suggest a significant correlation between the presence of sMICA and a lower incidence of rejection. 相似文献
45.
Health Risk Assessment of PCDD/PCDF Exposure for the Population Living in the Vicinity of a Municipal Waste Incinerator 总被引:1,自引:0,他引:1
Domingo JL Agramunt MC Nadal M Schuhmacher M Corbella J 《Archives of environmental contamination and toxicology》2002,43(4):0461-0465
Emissions of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) by municipal solid waste (MSW) incinerators
cause concern to the populations living in the vicinity of these facilities. In this study, the health risks of PCDD/F exposure
were assessed for adults and children living 500 and 1,000 m from the MSW incinerator. A comparative analysis was performed
before (1998) and after (2000) pronounced decreases in PCDD/F air emissions from the stack were noted as a consequence of
technical improvements in the facility. At 500 m, total environmental exposure to PCDD/Fs diminished from 5.102 × 10−5 to 1.271 × 10−5 ng I-TEQ/kg/day for adults, and from 8.131 × 10−5 to 2.656 × 10−5 ng I-TEQ/kg/day for children, which means a reduction of 75.1% for adults and 67.3% for children between 1998 and 2000. At
1,000 m, total environmental PCDD/F exposure diminished from 4.087 × 10−5 ng I-TEQ/kg/day in 1998 to 0.995 × 10−5 ng I-TEQ/kg/day in 2000 and from 6.294 × 10−5 ng I-TEQ/kg/day in 1998 to 1.983 × 10−5 ng I-TEQ/kg/day in 2000 for adults and children, respectively. However, these reductions are almost imperceptible compared
with the contribution of dietary intake of PCDD/F to total exposure to these contaminants. The present results corroborate
that for MSW incinerators with modern technologies, human PCDD/F exposure is mainly due to background contamination.
Received: 2 January 2002/Accepted: 30 May 2002 相似文献
46.
Nieves Derqui Joshua Nealon Ainara MiraIglesias Javier DíezDomingo Cedric Mah Sandra S. Chaves 《Influenza and other respiratory viruses》2022,16(5):862
PurposeInfluenza hospitalizations contribute substantially to healthcare disruption. We explored the impact of ageing, comorbidities and other risk factors to better understand associations with severe clinical outcomes in adults hospitalized with influenza.MethodsWe analysed multi‐season data from adults ≥18 years, hospitalized with laboratory‐confirmed influenza in Valencia, Spain. Severity was defined as intensive care unit (ICU) admission, assisted ventilation and/or death. Generalized estimating equations were used to estimate associations between risk factors and severity. Rate of hospital discharge was analysed with a cumulative incidence function.ResultsOnly 26% of influenza patients had their primary discharge diagnosis coded as influenza. Comorbidities were associated with severity among adults aged 50–79 years, with the highest odds ratio (OR) in patients with ≥3 comorbidities aged 50–64 years (OR = 6.7; 95% CI: 1.0–44.6). Morbid obesity and functional dependencies were also identified risk factors (ORs varying from 3 to 5 depending on age). The presence of increasing numbers of comorbidities was associated with prolonged hospital stay.ConclusionsInfluenza clinical outcomes are aggravated by the presence of comorbidities and ageing. Increased awareness of influenza among hospitalized patients could prompt clinical and public health interventions to reduce associated burden. 相似文献
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Escarlata Angullo-Martínez Enrique Carretero-Anibarro Ignacio Manuel Snchez Barrancos Xavier Cos Claramunt Domingo Orozco Beltrn Jos Luis Torres Baile Patxi Ezkurra Loiola en representacin del Grupo de Trabajo de Diabetes de la SemFyC en representacin del Grupo de Trabajo de Diabetes de la SemFyC 《Atencion primaria / Sociedad Espa?ola de Medicina de Familia y Comunitaria》2021,53(4)
Las circunstancias actuales provocadas por la COVID-19 nos obligan a los profesionales de atención primaria a idear nuevas formas de garantizar la atención sanitaria de nuestros pacientes con diabetes tipo 2 (DM2). Existen evidencias que respaldan la eficacia de la telemedicina en el control glucémico de los pacientes con DM2. Ante la rápida adaptación de la práctica clínica al uso de la telemedicina, el Grupo de Trabajo de Diabetes de la Sociedad Española de Medicina Familiar y Comunitaria (SemFyC) optó por elaborar un documento de consenso plasmado en un algoritmo de actuación/seguimiento telemático en la atención de los pacientes con DM2.Palabras clave: Telemedicina, Diabetes mellitus tipo 2, COVID-19 相似文献
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