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21.
In this study, the anti-tumour activity of selenium-protein polysaccharide (SPP), a water extract of the rich selenium Agaricus blazei, was tested both in vivo and in vitro. The results of in vivo experiments show that SPP at doses of 50 and 100 mg/kg inhibits proliferation of implanted Sarcoma 180 by 22 and 37.69%, respectively, and promotes lymphocyte transformation and natural killer (NK) cells activity in tumour bearing mice. During the in vitro experiment, we treated the tumour and non-tumour bearing mice with SPP, and prepared serum treated with SPP (SerumSPP). The results show that SerumSPP, whether from tumour or non-tumour bearing mice, significantly inhibits K562 cells proliferation and induces their apoptosis, and also significantly increases caspase-3 activity of K562 cells. However, the difference in anti-tumour activity of SerumSPP between tumour and non-tumour bearing mice is significantly different (p<0.01). The results, according to the studies both in vivo and in vitro, imply that SPP extracted from rich selenium A. blazei can inhibit growth of implanted Sarcoma 180 and promote lymphocyte transformation and NK cells activity in vivo. Additionally, SerumSPP can inhibit proliferation and cause apoptotic morphological changes and the fragmentation of internucleosomal DNA, and increase caspase-3 activity of K562 cells in vitro, which indicates that apoptosis of K562 cells induced by SerumSPP may be related to up-regulation of caspase-3. 相似文献
22.
对16例直肠癌旁0~5cm粘膜采用粘蛋白组织化学与电镜的方法对比观察。结果表明,移行区细胞有早期亚微结构的病理改变,杯状细胞及未分化细胞增多,有轻度异形性,并出现“双重特征”细胞。证明癌旁移行粘膜细胞成熟迟缓,应视为潜在癌前期改变。 相似文献
23.
Che Dong-yuan车东媛 Liu Shao-chun刘绍春and Huang Xiao-zhu黄晓珠Department of Pathology Tongji Medical University Wuhan 《中华医学杂志(英文版)》1989,102(7):563-567
There were 48 strains of thermophilic actinomyces isolated from the specimens of mouldy hay and sputum of the patients suffering from farmer’s lung (FL). Streptomyces thermohygroscopicus (STHs),one strain of them, was used for this investigation. The microorganisms were injected into the lungs of rabbits and rats by thyrocrico – or tracheocentesis. The result showed that the pathological changes in the lungs including macrophage alveolitis, granuloma formation and diffuse interstitial were similar to that induced by other thermophilic actinomyces. IgG and C3 deposition in the lesions were also observed by immunofluorescence examination. Specific immunocomplexes in the sera of some animals were detected by ELISA with the STHs was possibly one of the pathogens responsible for FL in China’s countryside. 相似文献
24.
Novel proteins with binding specificity for DNA CTG repeats and RNA CUG repeats: implications for myotonic dystrophy 总被引:7,自引:6,他引:7
While an unstable CTG triplet repeat expansion is responsible for myotonic
dystrophy, the mechanism whereby this genetic defect induces the disease
remains unknown. To detect proteins binding to CTG triplet repeats, we
performed bandshift analysis using as probes double- stranded DNA fragments
having CTG repeats [ds(CTG)6-10] and single- stranded oligonucleotides
having CTG repeats ss(CTG)8 or RNA CUG triplet repeats (CUG)8. The source
of protein was nuclear and cytoplasmic extracts of HeLa cells, fibroblasts
and myotubes. Proteins binding to the double-stranded DNA repeat
[ds(CTG)6-10], were inhibited by nonlabeled ds(CTG)6-10, but not by a
non-specific DNA fragment (USF/AD-ML). Another protein binding to ssCTG
probe and RNA CUG probe was inhibited by nonlabeled (CTG)8 and (CUG)8.
Nonlabeled oligos with different triplet repeat sequences, ss(CAG)8 or
ss(CGG)8, did not inhibit binding to the ss(CTG)8 probe. However, when
labeled as probes, the (CAG)8 and (CGG)8 bound to proteins distinct from
the CTG proteins and binding was inhibited by nonlabeled (CAG)8 or (CGG)8
respectively. The protein binding only to the RNA repeat (CUG)8 was
inhibited by nonlabeled (CUG)8 but not by nonlabeled single- or
double-stranded CTG repeats. Furthermore, the CUG-BP exhibited no binding
to an RNA oligonucleotide of triplet repeats of the same length but having
a different sequence, CGG. The CUG binding protein was localized to the
cytoplasm, whereas dsDNA binding proteins were localized to the nuclear
extract. Thus, several trinucleotide binding proteins exist and their
specificity is determined by the triplet sequence. The novel protein,
CUG-BP, is particularly interesting since it binds to triplet repeats known
to be present in myotonin protein kinase mRNA which is responsible for
myotonic dystrophy.
相似文献
25.
Detection of antibodies specific to an antigenic cell wall galactomannoprotein for serodiagnosis of Aspergillus fumigatus aspergillosis 总被引:3,自引:0,他引:3
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Chan CM Woo PC Leung AS Lau SK Che XY Cao L Yuen KY 《Journal of clinical microbiology》2002,40(6):2041-2045
Aspergilloma and invasive aspergillosis are important opportunistic infections caused by Aspergillus species, among which Aspergillus fumigatus is the most common species associated with human disease. We developed an enzyme-linked immunosorbent assay (ELISA)-based antibody assay with Afmp1p, a purified recombinant antigenic cell wall galactomannoprotein of A. fumigatus. Evaluation of the test with guinea pig sera against A. fumigatus and other pathogenic fungi indicated that this assay was specific for A. fumigatus. Clinical evaluation revealed that the assay was 100% sensitive for patients with aspergilloma and 33.3% sensitive for patients with invasive aspergillosis. No false-positive results were found for serum samples from 80 healthy blood donors, 6 patients with typhoid fever, 4 patients with melioidosis, 20 patients with penicilliosis marneffei, 5 patients with candidiasis, and 4 patients with cryptococcosis, indicating a high specificity of the test. Thus, this ELISA-based test for the detection of anti-Afmp1p antibody can be of significant value as a diagnostic for aspergillosis. 相似文献
26.
新生大鼠海马神经元原代培养方法的研究 总被引:18,自引:0,他引:18
目的 :研究和比较 3种不同培养神经元的方法 ,提供一种纯化效率和存活率均较高的培养技术。方法 :取新生SD大鼠的海马区 ,应用一般培养法、加阿糖胞苷法、加阿糖胞苷和神经生长因子法培养神经元 ,观察神经元的形态。用倒置显微镜观察和MTT比色分析检测神经元的存活率。用ABC免疫组化染色法 ,比较 3种不同培养方法在不同培养时间所获得神经元的纯度。结果 :加阿糖胞苷和神经生长因子培养组神经元生长良好 ,纯度和存活率均较高。结论 :加阿糖胞苷和神经生长因子培养神经元的方法具有简便可行 ,易于生长的优点 ,可作为神经元体外培养的良好模型 相似文献
27.
单睑下缘与睑缘间高度测量及临床关系的探讨 总被引:1,自引:0,他引:1
目的 为国人人类学积累资料,亦为探讨重睑术中设计重睑线的新方式。方法 对象为280例双眼眼部无畸形且均为单睑的青年人(男144人,女136人),测量单睑下缘与睑缘之间的内、中、外三处垂立距离。结果 男女各点均值分别是内眦点为4.0mm,中央点为55mm,外眦点为3.5mm。结论 单睑下缘不宜作为重睑术中设计重睑线的标志线,但在单睑下缘于内,外眦点处上方0.5mm-1mm,中央点处上方1.0mm-2mm作重睑术设计标志线较为适宜。 相似文献
28.
目的:探讨血小板源性生长因子(PDGF)在低氧肺动脉高压血管构形重建发生中的作用。方法:应用免疫组化技术结合计算机图像分析,检测了低氧大鼠腺泡内肺动脉(IAPA)PDGF-B链蛋白表达水平。结果:常氧时,IAPA仅有PDGF-B链蛋白弱表达;低氧1天时,IAPA便有较强的PDGF-B链蛋白表达,定位于IAPA的内皮和中膜,低氧3天至14天仅分布于中膜;低氧1、3、5、7、14天各时间点PDGF-B链蛋白表达分别为常氧组的1.53、1.59、1.56、1.62和1.42倍,差异有显著性(P<0.01)。结论:PDGF-B链蛋白可能参与了低氧肺动脉高压血管构形重建的发病过程 相似文献
29.
Ricardo Pietrobon Anand Shah Paul Kuo Matthew Harker Mariana McCready Christeen Butler Henrique Martins CT Moorman Danny O Jacobs 《BMC medical informatics and decision making》2006,6(1):32-11
Background
Although regulatory compliance in academic research is enforced by law to ensure high quality and safety to participants, its implementation is frequently hindered by cost and logistical barriers. In order to decrease these barriers, we have developed a Web-based application, Duke Surgery Research Central (DSRC), to monitor and streamline the regulatory research process. 相似文献30.
Correlation of AIB1 overexpression with advanced clinical stage of human colorectal carcinoma 总被引:7,自引:0,他引:7
AIB1, a member of the steroid receptor coactivator 1 family, has been cloned on 20q12 and is a candidate oncogene in human breast cancer. It is commonly amplified and overexpressed in several types of human cancers. In this study, we examined the expression of AIB1, as related to clinicopathologic features, in 85 human colorectal cancers (CRCs). The status of the number of AIB1 copies, p53 expression, and DNA ploidy was also analyzed. The overexpression of AIB1 was detected in 35% of CRCs. Amplification of AIB1 was observed in 10% of CRCs. In addition, the overexpression of AIB1 was observed more frequently in CRCs in later clinical stages (T3 N1 M0/T3 N0 2M1), compared with that in T3 N0 M0 stage (P < .05). These results suggest that overexpression of AIB1 might provide a selective advantage for the developmental growth and/or progression of subsets of CRCs. In addition, a significant correlation (P < .05) of overexpression of AIB1 with p53 overexpression as well as with aneuploid DNA content was observed in these CRCs. The overexpression of p53 was also correlated significantly with CRC DNA ploidy (P < .05). Furthermore, there was a substantial population of CRCs showing overexpression of both AIB1 and p53 protein and all had aneuploid DNA content; most of these were in the later clinical stage. These findings suggest a possible convergence of AIB1 with a pathway involving p53, which might induce chromosomal instability and affect the clinical phenotype of a subset of CRCs. 相似文献