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91.
Background: People with abnormal colour vision often report difficulty seeing coloured berries and flowers in foliage, which suggests they will have a diminished capacity for visual search when target objects are marked out by colour. There is very little experimental evidence of the effect of abnormal colour vision on visual search and none relating to search for objects in natural foliage. Method: We showed 79 subjects with abnormal colour vision (seven protanopes, 10 deuteranopes, 16 protanomals and 46 deuteranomals) and 20 subjects with normal colour vision photographs of natural scenes and asked them to locate clumps of red berries, to trace the length of a red string on grass and to name the season depicted in a photograph taken in the Autumn and the same scene photographed in the Summer. Colour vision was assessed using the Ishihara, the Medmont C100, the Farnsworth D15, the Richmond HRR and the Nagel anomaloscope. Results: All the subjects with abnormal colour vision located fewer clumps of red berries than those with normal colour vision. The subjects who failed the Farnsworth D15 performed significantly worse than those who passed but the distribution of scores in the two groups overlaps. The majority of subjects with abnormal colour vision could not trace the full length of the string: only 38 per cent of anomalous trichromats who passed the Farnsworth D15 test and three per cent of those who failed it were able to trace the full length of the string. Fifty‐five per cent of those classed as having a mild deficiency by the HRR test could trace the whole string. Most dichromats were unable to identify the Autumn season and those who did may have been assisted by guessing. Most (94 per cent) of those who passed the Farnsworth D15 test and all those classified as having a ‘mild’ deficiency by the HRR test could identify the season. Conclusions: All people with abnormal colour vision, even those with a very mild deficiency, have some degree of impairment of their ability to see coloured objects in natural surroundings. A pass at the Farnsworth D15 test or a ‘mild’ classification with the Richmond HRR test identifies those likely to have the least problems with visual search and identification tasks. The results have practical implications for the selection of personnel in occupations that involve visual search in natural terrain. 相似文献
92.
癌基因c-fos、c-jun蛋白在鳞状细胞癌皮损中的表达及意义 总被引:3,自引:0,他引:3
目的 探讨癌基因c fos、c jun的表达与皮肤鳞癌发生和发展的关系。 方法 采用免疫组化法对 6 0例皮肤鳞癌的c fos、c jun的表达情况进行检测 ,并与正常皮肤组织进行对照。 结果 c fos、c jun在正常皮肤组织不表达 ,在皮肤鳞癌中的表达阳性率分别为 6 1.7%和 4 8.3% ,其表达水平与癌组织的分化程度有关 (P <0 .0 5 ) ,肿瘤的分化程度越高其表达水平越高。 结论 c fos、c jun的表达水平可作为判定皮肤鳞癌分化的指标。 相似文献
93.
S H Jee S Y Won J E Yun J E Lee J S Park S S Ji 《International journal of gynaecology and obstetrics》2004,85(3):301-308
OBJECTIVES: Although some studies have reported that the arginine isoform on codon 72 of p53 increases the susceptibility to invasive cervical cancer, such data remain controversial. The objective of this study was to quantitatively summarize the evidence for such a relationship. METHODS: Our data sources consisted of a MEDLINE search of the literature published before December 2002, bibliography review, and expert consultation. Thirty-seven studies met the inclusion criteria. Information on sample size, study design, Hardy-Weinberg equilibrium, and method of genotype determination was abstracted by two reviewers using a standardized protocol. The overall odds ratio (OR) of the p53 gene on invasive cervical cancer was estimated using the Mantel-Haenzel method. RESULTS: The overall OR (95% confidence interval) for cervical cancer among those with the homozygous mutant (Arg/Arg) was 1.2 (1.1-1.3, P=0.001) compared with those with the heterozygous mutant (Arg/Pro). By a cellular type of cervical cancer, the overall OR among those with Arg/Arg was statistically significant in adenocarcinomas (1.7, 1.1-2.6, P=0.024), but not in squamous cell carcinomas (1.1, 0.9-1.2, P=0.960), compared with Pro/Pro. Compared with Arg/Pro, the OR among those with Arg/Arg was statistically significant in HPV types 16 (1,5, 1.2-2.0, P=0.002). CONCLUSIONS: Overall, the p53 gene was associated with increased risk for invasive cervical cancer. However, the risk varied by country, cellular, and HPV type. 相似文献
94.
检测25例脑肿瘤中抑制癌基因P53突变情况。突用复合PCR,聚合酶链反应-=单链构象多态性分析法,统计学处理采用X^2检验。结果:P53基因总的突变率为44.0%,其中第5外显子突变率为28.0%,第6外显子突变率12.0%,第7外显子突变率为12.0%,第8外显子突变率16.0%;病理分级Ⅱ级及其以上突变为72.7%, 相似文献
95.
石棉相关肿瘤p53基因突变的免疫组化及PCR—SSCP研究 总被引:3,自引:0,他引:3
为了分析石棉相关肿瘤p53基因的突变特点,对石蜡包埋的石棉相关肿瘤p53基因突变体蛋白的表达进行了免疫组化观察,提取染色体DNA,对p53基因的第5、7、8外显子进行PCR-SSCP及测序分析。免疫组化观察发现:在分析的10例病例中有5例阳性。PCR-SSCP分析发现7例(8处)发生突变,其中4处集中在第8外显子上。5例腺癌中有4例发生p53基因突变。测序发现热点区突变。提示:石棉相关肿瘤p53基因突变率高。 相似文献
96.
BACKGROUND: We have previously demonstrated that the proteolytic activity of Der p 1 selectively cleaves human CD25, the 55 kDa alpha subunit of the IL-2 receptor. As a result of cleavage of surface CD25, peripheral blood T cells produce less IFN-gamma and more IL-4, thereby leading to progressive polarization of the T cells towards a Th2 cytokine profile. Therefore, these observations underline the potential role of the proteolytic activity of Der p 1 in creating a microenvironment conducive for IgE synthesis. OBJECTIVE: To study the effect of T cells that have been conditioned by the proteolytic activity of Der p 1 on IgE synthesis by B cells. METHODS: We have examined this concept in experiments whereby T cells that have been exposed to either proteolytically active or inactive Der p 1 were cocultured with autologous B cells and IgE antibody synthesis was monitored. RESULTS: Here we demonstrate for the first time that coculturing T cells that have been in contact with proteolytically active Der p 1 with autologous B cells leads to augmentation of IgE antibody responses. CONCLUSIONS: The proteolytic activity of Der p 1 conditions human T cells, which then become empowered to trigger enhanced IgE synthesis by B cells. 相似文献
97.
98.
Hiroyoshi Suzuki Taisuke Otsuki Yuzo Iwasaki Ryuichi Katakura Hideshi Asano Mamoru Tadokoro Yoichi Suzuki Fumiaki Tezuka Hidehiro Takei 《Neuropathology》2002,22(1):40-47
The present case report describes a case of ganglioglioma with a distinct sarcomatous component in the left temporal lobe of a 59‐year‐old Japanese man. Neoplastic neuroglial tissue contained both benign and anaplastic glial components with a MIB‐1 labeling index of 0.1% and 12.0%, respectively. Sarcomatous tissue adjacent to the anaplastic glial tissue was dominated by pleomorphic fibroblastic cells with a MIB‐1 labeling index of 10.8%. They were immunoreactive for smooth muscle actin, type IV collagen, and alpha 1 antitrypsin, but not for desmin and CD34. Interestingly, some of the sarcomatous cells were double‐positive for smooth muscle actin and GFAP. The p53 protein had accumulated in the anaplastic astrocytes and sarcomatous cells, but direct DNA sequencing of PCR products failed to detect any mutation in the p53 gene (from exon 4 to exon 10). 相似文献
99.
目的:建立一种快速鉴定临床常见真菌菌种的方法。方法:选取真菌核糖体RNA的ITS区为靶基因,设计通用引物和种特异性探针,将3个属的6种临床常见真菌(白色念珠茵、热带念珠茵、光滑念珠茵、新型隐球菌、烟曲霉和黄曲霉)的种特异性探针加尾后固定于硝酸纤维素膜上;用标记生物素的真菌通用引物扩增11种医学真菌DNA,产物与固定在膜上的探针杂交。结果:通用引物可以扩增所试11种医学重要真菌的DNA,扩增片段长度约为560bp。6种真菌扩增产物只与其对应的探针杂交。结论:此方法快速、简便、特异,适合常规实验室开展。 相似文献
100.
目的 :研究cyclinD1 bcl 1和p2 7 kip1在脑胶质瘤中表达及其与病理分级和患者预后的关系。方法 :用免疫法组化技术对 4 8例不同恶性程度 (WHO分类法 )的脑胶质瘤组织和 12例非肿瘤组织中cyclinD1 bc1 1和p2 7 kip1蛋白的表达作了检测 ,用图像分析系统定量分析 ,并与临床资料紧密相联系进行统计学处理。结果 :两种蛋白的免疫反应复合物定位于细胞核。其在脑胶质瘤中的阳性表达都高于非肿瘤组织 (P <0 0 5 ) ,cyclinD1 bcl 1阳性颜色的数量和强度都随肿瘤的恶性程度升高而增加 (P <0 0 5 ) ,相反p2 7 kip1阳性染色的数量和强度都随肿瘤的恶性程度升高而降低 (P <0 0 5 )。cyclinD1 bcl 1的高表达或 和p2 7 kip1的低表达预示着预后差。结论 :CyclinD1 bcl 1和p2 7 kip1的异常表达可能与脑胶质瘤的发生发展密切相关 ,二者可能有协同作用。二者的表达都可作为判断预后的一个指标 相似文献