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91.
Simplified purification of human basophils 总被引:7,自引:0,他引:7
Tsang S Hayashi M Zheng X Campbell A Schellenberg RR 《Journal of immunological methods》2000,233(1-2):13-20
Studies of human basophils have been limited by the low number present in peripheral blood and the difficulties of purification to homogeneity with reasonable yield and functional status. Reproducible purification of human basophils to 96.5+/-0.5% with a yield of 40.8+/-5.3% was obtained by negative selection using immunomagnetic beads following initial separation by density gradient centrifugation. Isolated cells demonstrated complete viability by vital dye exclusion and spontaneous histamine release following incubation of <5%. Stimulation with anti-IgE or calcium ionophore A23187 caused histamine release and leukotriene C(4) production. Basophils demonstrated dose-dependent chemotaxis to monocyte chemotactic protein-3. This simplified methodology results in fully functional basophils in very high purity and good yield. 相似文献
92.
Plasmids encoding foot-and-mouth disease virus VP1 epitopes elicited immune responses in mice and swine and protected swine against viral infection 总被引:20,自引:0,他引:20
VP1 is a capsid protein of foot-and-mouth disease virus (FMDV) and contains epitopes of the virus. Plasmids encoding two VP1 epitopes (amino acid residues 141-160 and 200-213) and a host-self immunoglobulin molecule were constructed to produce a new type of FMD DNA vaccine. Two plasmids, namely, pCEIM and pCEIS, containing mouse immunoglobulin (IgG) or swine IgG were subjected to immunogenicity testing in mice and swine, respectively. In mice administrated pCEIM in the abdomen using a genegun, both FMDV-specific T-cell proliferation and neutralizing antibodies were detected. In swine immunized with pCEIS at the back of the ear, immune responses were achieved after the second administration. Swine showed a T-cell proliferative response with a stimulation index (SI) of up to 8.1 and a neutralizing antibody response that was able to protect suckling mice from 10(2) LD(50) (lethal dose 50) FMDV challenge. To compare the immunogenicity of the DNA-based vaccine candidate, versus the protein-based vaccine candidates, a second group of swine was immunized with the protein F1-scIgG, which was encoded by the plasmid pCEIS. Injection with F1-scIgG elicited a T-cell proliferative response of SI < 1.7 and a neutralizing antibody response that protected suckling mice from up to 10(5) LD(50) FMDV challenge. In the challenge test, three of three swine immunized with pCEIS were fully protected from FMDV challenge. 相似文献
93.
Wang Z Samuelson J Clark CG Eichinger D Paul J Van Dellen K Hall N Anderson I Loftus B 《Molecular and biochemical parasitology》2003,129(1):23-31
Entamoeba invadens, a parasite of reptiles, is a model for the study of encystation by the human enteric pathogen Entamoeba histolytica, because E. invadens form cysts in axenic culture. With approximately 0.5-fold sequence coverage of the genome, we were able to get insights into E. invadens gene and genome features. Overall, the E. invadens genome displays many of the features that are emerging from ongoing genome sequencing efforts in E. histolytica. At the nucleotide level the E. invadens genome has on average 60% sequence identity with that of E. histolytica. The presence of introns in E. invadens was predicted with similar consensus (GTTTGT em leader A/TAG) sequences to those identified in E. histolytica and Entamoeba dispar. Sequences highly repeated in the genome of E. histolytica (rRNAs, tRNAs, CXXC-rich proteins, and Leu-rich repeat proteins) were found to be highly repeated in the E. invadens genome. Numerous proteins homologous to those implicated in amoebic virulence, (Gal/GalNAc lectins, amoebapores, and cysteine proteinases) and drug resistance (p-glycoproteins) were identified. Homologs of proteins involved in cell cycle, vesicular trafficking and signal transduction were identified, which may be involved in en/excystation and cell growth of E. invadens. Finally, multiple copies of a number of E. invadens genes coding for predicted enzymes involved in core metabolism and the targets of anti-amoebic drugs were identified. 相似文献
94.
TRIO amplification and abundant mRNA expression is associated with invasive tumor growth and rapid tumor cell proliferation in urinary bladder cancer 下载免费PDF全文
Zheng M Simon R Mirlacher M Maurer R Gasser T Forster T Diener PA Mihatsch MJ Sauter G Schraml P 《The American journal of pathology》2004,165(1):63-69
Studies by comparative genome hybridization have suggested that 5p amplification is related to tumor progression in urinary bladder cancer. In this study seven genes (TAS2R, ADCY2, DNAH5, CTNND2, TRIO, ANKH, and MYO10) located to 5p15.31-5p15.1 were analyzed by fluorescence in situ hybridization using a tissue microarray containing samples from tumors and cell lines with known 5p amplification by comparative genome hybridization. Amplification frequency was highest for TRIO, which maps to 5p15.2 and encodes a protein with a putative role in cell-cycle regulation. To further investigate the role of TRIO amplification in bladder cancer, a tissue microarray containing samples from 2317 bladder tumors was used for fluorescence in situ hybridization analysis. TRIO amplification was strongly associated with invasive tumor phenotype, high tumor grade, and rapid tumor cell proliferation (Ki67 LI) (P < 0.0001 each). Only 7 of 456 pTaG1/G2 tumors (1.5%) but 62 of 485 pT1-4 carcinomas (12.8%) had TRIO amplification. TRIO amplification was not associated with poor prognosis. Using a frozen bladder tumor tissue microarray RNA in situ hybridization confirmed that TRIO is up-regulated in amplified tumors. It is concluded that TRIO up-regulation through amplification has a potential role in bladder cancer progression. 相似文献
95.
血糖感应型胰岛素给药智能载体的研究进展 总被引:1,自引:0,他引:1
胰岛素控制释放高分子载体系统一直是国内外科技工作者的研究热点 ,迄今已经研究报道了多种具有不同工作原理的血糖感应型胰岛素给药智能载体。本文基于国内外大量研究文献 ,综述了血糖感应型胰岛素控制释放智能化高分子载体的研究进展。 相似文献
96.
Study on the metastatic mechanisms of human giant-cell lung carcinoma comparison between the strains C and D 总被引:4,自引:0,他引:4
Mei L Lezhen C Po Z Zheng G Yali L Nan L 《Asian Pacific journal of allergy and immunology / launched by the Allergy and Immunology Society of Thailand》1998,16(4):167-176
The biologic characteristics of the two human giant-cell lung carcinoma strains with high (strain D) and low metastatic potential (strain C) were studied, including karyotype of chromosome, intracellular free calcium ([Ca2+]i), morphologic changes of cell surface and the expression of nm23-H1, p53, ras, c-myc, c-erbB2, bcl-2 genes and PCNA. The correlation between different biologic features and the metastatic potential of the two strains was analyzed. We found: 1) Both strains had the karyotypic abnormality of -13, -14, -15, +20, +21 with seven same marker chromosomes. Only strain D had the karyotypic abnormality of +7, -17, -18, +X, 7p+; 2) [Ca2+]i of the strain C (984.7 +/- 573.8) and D (517.6 +/- 216.6) was significantly different (p < 0.05). The amplitude of intracellular calcium oscillations of strain C was lower than the one of strain D; 3) strain C had more villous-like protrusions on the cell surface, whereas strain D had more bubble-like protrusions; 4) The expression of nm23-H1 and p53 protein of strain C was all higher than that of strain D. The expression of PCNA of strain C was lower than strain D; 5) nm23-H1 mRNA levels of strain C was lower than that of strain D. We consider that the karyotype of chromosomes, intracellular free calcium, the structure of cell membrane and the expression of nm23-H1 gene, p53 gene, PCNA could be closely related to the metastatic potential of human giant-cell lung carcinoma. They could be used as the sign for judging whether the tumor will metastasize in clinical practice as well as in judging the prognoses of patients. 相似文献
97.
Brain images produced on the EMI 7070 scanner exhibit a "cupping" artefact due to a combination of beam hardening and scatter effects. The magnitude of the artefact is assessed by statistically analysing a series of concentric regions of interest in the final image. Once the magnitude has been determined it can be subtracted from the image. While the result of the technique does not modify the clinical analysis of images it does increase the observer's appreciation of the image. Both the technique and clinical results are presented, and the implications of this type of reconstruction artefact removal discussed. 相似文献
98.
催经止孕药Ru-486的临床药代动力学 总被引:4,自引:1,他引:3
应用高效液相色谱法(HPLC)研究了抗孕激素药,Ru-486的临床药代动力学。六名志愿受试者,一次口服Ru-486 50毫克后测得该药的药代动力学各项参数,血药半寿期t 1/2 33.0小时,一级消除速率常数Kel 0.021 hr~(-1),血药表观容积Vd 120.1 Liter,体内血药总廓清率Cl2.5 Liter/hr,药-时曲线下面积Auc 19825.1 ng/ml/hr。实验表明,服药后一小时血药浓度迅即达高峰,随后转入消除期,血浆药物浓度在消除相的头4~8小时消除较快,而后逐渐减慢,持续24小时,到48小时血药浓度已较低(0.15±0.07μg/ml)。 相似文献
99.
Zheng Ying-jian郑英键and Li Qing-you李庆友Wuhan Second Municipal Hospital Wuhan 《中华医学杂志(英文版)》1986,99(3):191-194
lve cirrhotic patients underwent subtotal
splenectomy. The operative technique involved pre-
servation of anatomic segments and suture of an
omental patch to the residual spleen. With knowledge
on segmental vascular anatomy in splenomegaly, sub-
total splenic resection can be readily accomplished
with ease and safety. Follow-up of the 12 patients
showed that the preserved spleen had normal uptake
of 51Cr denatured erythrocyte isotope, high grade
serum IgM, and effect of alleviating fever after
splenectomy. Splenic scan and clinical immunologic
survey revealed the functional capacity of splenic
remnant, and the lower percentage of "pocked"
RBCs, an important clue to eusplenia. Thus, the
normal function and size retained of the residual
spleen were saved. If long-term follow-up confirms
the value of segmental splenectomy, it may become
an adjuvant treatment in lowering portal hyperten
sion in cirrhotic patients. 相似文献
100.
周围神经炎系指由于中毒、感染、感染后或变态反应等所引起的多数周围神经同时发病。临床表现为多发性或单一性的周围神经麻痹,对称性或非对称性肢体远端感觉障碍,弛缓性瘫痪及自主神经功能障碍的疾病。胶鞋中的聚氯乙烯经皮肤中毒致周围神经炎临床未见报道,需引起人们高度警惕,现将1997~2000年我院收治12例经皮肤中毒致周围神经炎患者报道如下。 相似文献