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941.
Peng R; Al-Katib A; Knowles DM d; Lu L; Broxmeyer H; Tolidjian B; Chiao JW; Koziner B; Wang CY 《Blood》1984,64(6):1169-1178
A series of monoclonal antibodies recognizing myeloid differentiation antigens were prepared by immunizing Balb/c mice with HL-60 cells. Hybrids secreting antibodies reactive with HL-60 cells but unreactive with peripheral blood mononuclear cells were isolated and further cloned. One clone was found to produce an IgG2a antibody recognizing an 85,000-dalton molecular weight surface glycoprotein, and a second clone was found to produce an IgM antibody recognizing a heat-stable determinant present on a glycolipid. We have termed these antigens Pro- Im1 and Pro-Im2, respectively (Pro for using HL-60 promyelocytes as an immunogen and Im for the presence of these antigens on immature cells). alpha Pro-Im1 and alpha Pro-Im2 were used to investigate the surface expression and tissue distribution of these two antigens. Pro-Im1 and Pro-Im2 were found to be brightly expressed on a fraction of fetal liver hematopoietic and bone marrow cells. Both antibodies mediated complement-dependent inhibition of CFU-GM, BFU-E, and CFU-GEMM formation assayed by soft agar colony and burst formation, indicating the expression of these antigens by early hematopoietic precursor cells. This was further confirmed by the induction of HL-60 cells by TPA to differentiate into more mature monocytes and macrophages, accompanied by the loss of both antigens. Pro-Im1 and Pro-Im2 were absent from peripheral blood monocytes, erythrocytes, and platelets, but Pro-Im2 was expressed on granulocytes. Both antigens were absent from thymocytes and peripheral T cells. Cytofluorographic analysis suggested their absence from peripheral blood B cells but that both were expressed on a minority of tissue B cells. Analysis of 150 cases of various myeloid and lymphoid malignancies demonstrated Pro-Im1 and Pro-Im2 expression on myeloblasts and promyelocytes from some acute myelogenous leukemias as well as some B cell malignancies, suggesting that these antigens are shared by early hematopoietic cells and a subset of B cells. 相似文献
942.
Variable expression of coxsackie-adenovirus receptor in thyroid tumors: implications for adenoviral gene therapy. 总被引:2,自引:0,他引:2
Derek K Marsee Douangsone D Vadysirisack Carl D Morrison Manju L Prasad Charis Eng Quan-Yang Duh Katherine A Rauen Richard T Kloos Sissy M Jhiang 《Thyroid》2005,15(9):977-987
Adenoviral gene therapy represents a novel approach for the treatment of aggressive thyroid carcinomas. Both coxsackie-adenovirus receptor (CAR) and integrins have been shown to be the major determinants for adenoviral infectivity in many types of cancer cells, yet conflicting results have been reported. In this report we examine these factors mediating adenoviral infection in thyroid cells and to evaluate CAR expression in various types of thyroid cancer. We found that neither expression levels of CAR nor integrins are solely predictive of adenoviral infectivity in thyroid cells. However, the absence of CAR was associated with poor adenoviral infectivity in immortalized rat FRTL-5 cells. Moreover, preincubation with alpha-CAR antibody decreased infectivity in FTC 238 cells, a human thyroid tumor line. These results indicate that CAR does play a role in adenoviral infection of thyroid cells. Immunohistochemical analysis revealed that CAR is expressed at the cell surface in the majority of malignant thyroid tumors. We further show that adenoviral infectivity in some thyroid cancer cells can be improved by poly-L-lysine. Our study warrants a functional method to evaluate adenoviral infectivity should be developed and instituted prior to clinical trials of adenoviral gene therapy in patients with advanced thyroid cancer. 相似文献
943.
目的:观察胰岛素对严重烧伤所致的急性肺损伤的保护效应。方法:实验于2006-01/08在解放军第四军医大学西京医院全军烧伤中心实验室完成。取成年雄性SD大鼠36只,随机分成3组,每组12只:①烫伤 胰岛素组:水浴锅94℃,20s,制备30%总体表面积全层皮肤烫伤模型,伤后即刻腹腔注射生理盐水40mL/kg,并皮下注射胰岛素3U/kg。②烫伤组:造模和腹腔注射同烫伤 胰岛素组,皮下注射等体积生理盐水。③假烫组:用室温水浴模拟烫伤过程,伤后不给予补液。烫伤24h后,收集动脉血测定超氧化物歧化酶活性,收集支气管肺泡灌洗液测定蛋白含量,取肺组织进行苏木精-伊红染色观察病理变化,并测定髓过氧化物酶活性,同时电镜观察胸主动脉血管内皮细胞变化情况。结果:36只大鼠进入结果分析。①肺病理变化:烫伤 胰岛素组肺脏渗出和水肿较烫伤组明显减轻。②肺泡灌洗液中蛋白的质量浓度:烫伤组和烫伤 胰岛素组高于假烫组[(702.9±169.5),(486.5±149.2),(240.5±140.7)mg/L,P<0.05],烫伤 胰岛素组低于烫伤组(P<0.05)。③肺脏髓过氧化物酶活性:烫伤 胰岛素组低于烫伤组[(36.01±8.17),(59.51±12.50)nkat/g,P<0.05],与假烫组比较差异不显著。④血清超氧化物歧化酶活性:烫伤组和烫伤 胰岛素组低于假烫组[(2.27±0.18),(2.63±0.19),(2.81±0.21)mkat/L,P<0.01,0.05],烫伤 胰岛素组高于烫伤组(P<0.01)。⑤电镜下可见烫伤 胰岛素组内皮细胞损伤较烫伤组轻。结论:严重烧伤早期外源性胰岛素干预后可减轻急性肺损伤,具有明显的肺脏保护作用,这种作用可能与胰岛素的内皮细胞保护效应有关。 相似文献
944.
945.
Christenson RH Mandichak JJ Duh SH Augustyn JM Thompson JC 《Clinica chimica acta; international journal of clinical chemistry》2003,327(1-2):157-164
BACKGROUND: Therapeutic monitoring of lithium is important because of its narrow therapeutic range and therapeutic index, low protein binding and single route of elimination. We characterized a new photometric method that avoids the specialized requirements of ion-specific electrode (ISE), atomic absorption and flame emission methods. METHODS: Minimum detectable concentration (MDC), linearity and calibration drift over 65 days were determined. Within-run, between-run and total imprecision were assessed over 20 days in accordance with NCCLS EP5. Interference studies were conducted for 46 endogenous and exogenous compounds. Two production lots of the new photometric method (LI) were compared on the Dimension(R) RxL system and two ISE methods [Ciba Corning (n=124) and DuPont (n=131)], an established photometric method (Vitros) 950 system; n=63) and atomic absorption (Thermo-Jerell Ash; n=63). RESULTS: The MDC was 0.04 mmol/l. Linearity was demonstrated from 0.12 to 5.8 mmol/l by the regression equation: observed=(1.01 x expected)-0.0005 mmol/l, S(y/x)=0.03 mmol/l, r=0.999. Drift for the lithium calibrators over the 65-day study period was <5%, except for the lowest calibrator, which showed 0.04 mmol/l drift. None of the 46 potential interfering substances showed greater than a 6.5% difference between control and test solutions. ISE method comparisons showed the following: LI=(1.08 x Ciba Corning ISE)-0.15 mmol/l, S(y/x)=0.05, r=0.999, and LI=(1.03 x DuPont ISE)+0.00 mmol/l, S(y/x)=0.06 mmol/l, r=0.999. Comparison of the LI method with the atomic absorption and Vitros system showed proportionality error <10%. Bias between the LI method and atomic absorption was 7%, substantially less than that documented in proficiency surveys for the Vitros and other systems. No lot-to-lot or site-to-site differences were observed. CONCLUSION: This new photometric method is an attractive alternative for Li measurement and is adaptable to instruments having spectrophotometric capability. 相似文献
946.
Lin Li Jing Wang Cheng-Cheng Tong Chi-Yi He 《Hepatobiliary & pancreatic diseases international : HBPD INT》2023,22(3):282-287
Background: The risk factors for the recurrent choledocholithiasis after endoscopic retrograde cholangiopancreatography(ERCP) have not been well studied. The aim of this study was to explore the risk factors of recurrent choledocholithiasis. Methods: We carried out a retrospective analysis of data collected between January 1, 2010 and January 1, 2020. Univariate analysis and multivariate analysis were used to explore the independent risk factors of recurrent choledocholithiasis following therape... 相似文献
947.
The aim of this study was to introduce Ag–Cu phase nanopowder as an additive to improve the corrosion behavior of dental amalgams. A novel Ag–Cu nanopowder was synthesized by the precipitation method. An amalgam alloy powder (World-Cap®) was added and mixed with 5 wt.% and 10 wt.% of Ag–Cu nanopowders, respectively, to form experimental amalgam alloy powders. The original alloy powder was used as a control. Alloy powders were examined using X-ray diffraction, transmission electron microscopy (TEM), scanning electron microscopy and electron probe microanalysis. Amalgam disk specimens of metallurgically prepared were tested in 0.9% NaCl solution using electrochemical methods. The changes in the corrosion potential and anodic polarization characteristics were determined. Corrosion potential data were analyzed statistically (n = 3, analysis of variance, Tukey’s test, p < 0.05). The diameters of lamellar structure Ag–Cu nanoparticles were measured to be approximately 30 nm. The composition of the Ag–Cu nanoparticles determined by TEM–energy-dispersive spectroscopy was 56.28 at.% Ag–43.72 at.% Cu. A light-shaded phase was found mixing with dark Cu–Sn reaction particles in the reaction zones of Ag–Cu nanoparticle-doped amalgams. The Ag–Cu nanoparticle-doped amalgams exhibited zero current potentials more positive than the control (p < 0.05) and no current peak was observed at −325 mV that related to Ag–Hg phase and Cu6Sn5 phase in anodic polarization curves. The results indicated that the corrosion resistance of high-copper single-composition amalgam could be improved by Ag–Cu nanoparticle-doping. 相似文献
948.
949.
Elias Jabbour Maral DerSarkissian Mei Sheng Duh Nora McCormick Wendy Y. Cheng Lisa J. McGarry Ariadne Souroutzidis Hui Huang Susan O’Brien Farhad Ravandi Hagop M. Kantarjian 《Clinical Lymphoma, Myeloma & Leukemia》2018,18(4):257-265