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101.
Interleukin-1, a peptide produced by monocytes, histiocytes, and interdigitating reticulum cells, plays an important role in the regulation of immune function. In this styde, we examined the production of interleukin-1 in 115 patients with a variety of human lymphomas by using a rabbit anti-interleukin-1 antibody and the immunoperoxidase technique. Interleukin-1 was detected in Reed-Sternberg cells from 20 patients with Hodgkin's disease as well as in neoplastic cells from 9 patients with true histiocytic lymphoma or malignant histiocytosis. In the other 86 cases, which included T- and B-cell lymphomas, no interleukin-1 could be detected. This result indicates a close relationship between Hodgkin's disease and true histiocytic malignancies and provides additional evidence to support our hypothesis that Reed-Sternberg cells are related to interdigitating reticulum cells.  相似文献   
102.
本文采用部分肋骨切除术,切除15只家兔双侧5、6、7、8肋中任一肋距脊柱约2cm处一段长约1cm的肋骨。一周后对受冲击波致伤的肺肋面的出血情况进行解剖观察,发现肺肋面的出血条纹呈“工”字形,从而为冲击伤肺肋面的平行出血条纹是肋间压痕这一观点找到了直接的实验证据。  相似文献   
103.
HLA-DR, DQ antigens in North American Caucasians   总被引:1,自引:0,他引:1  
HLA-DR, DQ specificities are determined by serological methods in 2,586 North American Caucasians. Antigen frequency, gene frequency and haplotype frequency are computed for each phenotype observed. The DR and DQ loci antigen distributions are well-fitted to a Hardy-Weinberg equilibrium (p greater than 0.25 for DR locus, p greater than 0.10 for DQ locus). All World Health Organization (WHO) recognized HLA-DR,DQ specificities were found except HLA-DRw18, which has been identified only in the black population. DR and DQ linkage disequilibria among recently defined splits is observed. The following DR and DQ associations are found: DR1 and DQw5; DR4 and DQw7, DQw8; DR7 and DQw2, DQw9; DR8 and DQw4, DQw6, DQw7; DR9 and DQw2, DQw9; DRw10 and DQw5; DRw11 and DQw6, DQw7; DRw12 and DQw5, DQw7; DRw13 and DQw6, DQw7; DRw14 and DQw5, DQW7; DRw15 and DQw6, DQw7; DRw16 and DQw5; DRw17 and DQw2. In this large study population, the following unusual DR and DQ associations are found: DR4, DQw2; DR4, DQw1; DR1, DQw7; DR7, DQw5; DRw17, DQw6; and other unusual haplotype phenotypes containing DRX, DQX.  相似文献   
104.
用放射免疫分析法和比浊法测定PAI0134对大鼠血浆血栓素B2浓度,血小板TXB2生成血小板聚集的影响。静脉注射API013470mg或100mg.kg显著降低血浆TXB2浓度,其降低2率分别为38.8%和51.6%,API0134明显抑制ADP诱导的大鼠血小板聚集和TXB2生成,抑制率分别为27.8%,39.5%,和41.4%,53.6%,两抑制率间呈显著正相关。  相似文献   
105.
We have developed small-volume (50 or 250 μl)-format branched-DNA assays for human immunodeficiency virus type 1 (HIV-1) RNA for use with specimens in which the volume is limited and/or a high viral load is anticipated. These formats exhibited good correlation with the standard 1-ml format; high specificity, reproducibility, and linearity; and no significant difference in the quantification of HIV-1 subtypes.  相似文献   
106.
107.
The objectives were (1) to determine the effect of the erythrocyte aggregation level (wide range of aggregation) and shear rate (which also affects aggregation) on the ultrasound backscattered power, and (2) to evaluate the reproducibility of the ultrasound method. Experiments were performed under steady flow (100–1250 ml/min) in a 12.7 mm diameter vertical tube. Doppler ultrasound at 10 MHz was used to measure simultaneously the velocity and the backscattered power across the tube. For each radial position, the shear rate was computed from the derivative of the velocity profile. The backscattered power decayed exponentially as a function of the shear rate, and for a given shear rate, the power increased monotonically with the level of aggregation measured by laser reflectometry. Using blood samples simulating hypo-, normal, and hyperaggregating erythrocytes, the power of the ultrasound signal varied respectively by –7.8, –13.2, and –16.1 dB as a function of the shear rate (from 0.4 to 50 s–1). The reproducibility of the backscattered power was 5.5 dB, which is less than the variations observed as a function of the shear rate. In conclusion, ultrasound backscattering is sensitive to the level of erythrocyte aggregation. At a first glance, ultrasound seems less accurate when compared to laser reflectometry but it is suggested that this is because ultrasound backscattering may be sensitive to structural aggregate changes that are not detected by the laser method. © 2000 Biomedical Engineering Society. PAC00: 8718-h, 8719Tt, 8750Kk  相似文献   
108.
Chronic hypoxia has been newly proposed as a common mechanism of tubulointerstitial fibrosis in the progression of various chronic inflammatory renal diseases, where PAI-1 plays an important role in the accumulation of extracellular matrix (ECM) through inhibition of plasmin-dependent ECM degradation. In the present study, we investigated the presence of PAI-1 in renal tubular cells by immunostaining renal biopsy samples. We also closely examined the effects of hypoxia and TNF-alpha on PAI-1 expression in cultured human proximal renal tubular cells (HRCs). Confluent cells growth-arrested in DMEM for 24h were exposed to hypoxia (1% O2) and/or TNF-alpha at 10 ng/ml for 24 hours. Amounts of PAI-1 protein and mRNA after stimulation were measured by ELISA and TaqMan quantitative PCR, respectively and compared to those in cells incubated under control conditions (18% O2 without TNF-alpha). HIF-1alpha was demonstrated by immunoblot analysis. In crescentic glomerulonephritis, clusters of proximal tubules were specifically stained for PAI-1. Treatment of 24 hours with hypoxia, TNF-alpha and their combination induced a 2.7-fold, a 1.8-fold, and a 4.6-fold increase in PAI-1 protein secretion, and produced a 3.6-fold, a 3.3-fold, and a 12.1-fold increase at the PAI-1 mRNA level, respectively. Immunoblot analysis revealed that hypoxia-inducible factor-1alpha (HIF-1alpha) was markedly accumulated in the nuclear fraction after 16-hours exposure of HPTECs to hypoxia but not to TNF-alpha. In conclusion, hypoxia induces PAI-1 expression via remarkable nuclear accumulation of HIF-1alpha in HRCs. TNF-alpha can enhance this hypoxia-induced PAI-1 expression.  相似文献   
109.
Horimoto  T.  Limcumpao  J. A.  Xuan  X.  Ono  M.  Maeda  K.  Kawaguchi  Y.  Kai  C.  Takahashi  E.  Mikami  T. 《Archives of virology》1992,126(1-4):283-292
Summary Heterogeneity of 9 feline herpesvirus type 1 (FHV-1) strains consisting of the prototype C27 strain, one French isolate, six Japanese isolates, and the attenuated vaccine F2 strain was examined by biological, immunological, and molecular biological methods. No significant difference was observed in virus growth and antigenic properties among the strains in Crandell feline kidney cell cultures. Hemagglutination activity was also detected in all extracts of cells infected with each strain. However, in immunoblot analysis, a virus-structural immunogenic protein with an Mr of 36 kDa was lacking in 2 strains, one of which was the vaccine F2 strain, whereas the other immunogenic proteins including three kinds of major glycoproteins were detected in all strains without differences in electrophoretic mobilities. Furthermore, when restriction endonuclease analysis was performed to examine the genomic heterogeneity of strains, the cleavage patterns with the enzymeMluI showed a genomic heterogeneity between wild and vaccine strains. In contrast, only a slight variation in the sizes of some fragments was shown with most of the 7 other enzymes used. These results indicated that the lack of the 36 kDa protein and theMluI cleavage pattern could be used as markers of the vaccine F2 strain. The specific markers are important not only to control the quality of the vaccine but also to evaluate the vaccine immunity in FHV-1 infection in cats.  相似文献   
110.
Yuan X  Yao Z  Shan Y  Chen B  Yang Z  Wu J  Zhao Z  Chen J  Cong Y 《Virus research》2005,114(1-2):70-79
The open reading frame 3 (ORF3) of the severe acute respiratory syndrome coronavirus (SARS-CoV) genome encodes a predicted 154-amino acid protein, which lacks similarities to any known protein, and is named 3b. In this study, it was shown that 3b protein was predominately localized to nucleus with EGFP tag at its N- or C-terminus. The localization patterns were similar in different transfected cells. Immuno-fluorescence assay revealed that 3b protein was co-localized well with C23 in nucleolus. C23, B23 and fibrillarin all are important nucleolar proteins, which localize in the region of the nucleolus. Co-transfection of p3b-EGFP with pC23-DsRed, pB23-DsRed and pfibrillarin-DsRed further confirmed 3b's nucleolus localization. With construction of serial truncated mutants of 3b, a region (residues 134-154 aa) responsible for nucleolar localization was determinated in 3b protein. These results provide a new insight for further functional studies of SARS-CoV 3b protein.  相似文献   
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