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61.
62.
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
63.
隐动脉筋膜蒂的交腿皮瓣修复小腿严重软组织缺损 总被引:7,自引:2,他引:5
目的探讨一种小腿严重软组织缺损的修复方法。方法以健侧隐动脉为蒂的顺行或逆行交腿皮瓣修复患侧小腿软组织缺损。结果本组8例均有效地覆盖受区创面,随访三个月,皮瓣全部成活。结论该皮瓣不牺牲小腿的重要血管,质地与受区相似,方法简单易行,血运可靠,血管蒂长,是修复小腿严重软组织缺损的较好方法。 相似文献
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65.
自1990年以来收治直径在2-5.6cm的大、巨型垂体腺瘤33例。依肿瘤生长形态与扩展范围将其简略分为三种类型。A型:瘤体位于鞍内或侵入蝶窦;B型;瘤体呈椭圆形或哑铃向鞍上扩展,三脑室明显移位抬高;C型:瘤体巨大侵入三脑室阻塞室间孔或明显的鞍周扩展。 相似文献
66.
bcl-2反义寡核苷酸对膀胱癌BIU87细胞株的影响 总被引:2,自引:0,他引:2
目的:探讨bcl-2反义寡核苷酸对培养的膀胱癌BIU87细胞株的影响.方法:采用bcl-2基因第1外显子的反义寡核苷酸,以硫代磷酸修饰(PS-ASON),序列为5′-TCTCCCAGCGTGCGCCAT-3′,与膀胱癌细胞株BIU87共同孵育作为实验组.加入正义的bcl-2寡核苷酸,序列为5′-TACCGCGTGCGACCCTCT-3′(PS-SON)作为对照组,用流式细胞仪检测细胞凋亡和坏死率,电镜观察细胞形态变化.结果:与对照组相比,实验组的细胞坏死率明显上调,电镜下细胞形态呈坏死改变.结论:bcl-2的反义寡核苷酸引起膀胱癌细胞大量坏死,可能成为膀胱癌的治疗方法之一. 相似文献
67.
We have previously reported the purification of a 37 kDa platelet agglutinating protein (PAP p37) from the plasma of a patient with thrombotic thrombocytopenic purpura (TTP) that was shown to be present in a subset of TTP patients. To gain further insight into the interaction between PAP p37 and platelets, we have studied the properties of PAP p37 binding to platelets. Washed human platelets from two normal donors and two TTP patients after recovery were used for the experiments. The PAP p37 binding to platelets was specific, concentration dependent and saturable. Scatchard analysis demonstrated about 20,564-27,090 PAP p37 binding sites per platelet. Stimulation of platelets with thrombin or ADP did not have any significant effect on its binding. Thiol- and serine-specific protease inhibitors did not inhibit PAP p37 binding to the platelets. Sugars such as glucose, fructose, mannose, and sialic acid, at 40 mM, inhibited its binding to platelets by 44%, 73%, 79%, and 91% respectively, but galactose and amino sugars did not have any significant effect. At 250 micrograms/ml, Concanavalin-A inhibited 42% of binding, but other lectins, such as phytohemagglutinin-P, potato lectin and helix pomatia lectin (snail), did not. Pre-incubation of 125I-PAP p37 with the adult human IgG, decreased its binding to the platelets. The monoclonal antibodies to GP Ib (6D1) and GP IIb-IIIa complex (10E5) did not inhibit the binding of 125I-PAP p37 to platelets. Fibrinogen and von Willebrand factor did not affect the binding either. These results suggest that PAP p37 binds to platelets on the sites other than GP Ib or GP IIb-IIIa complex. 相似文献
68.
Effect of fathers'' age and birth order on occurrence of congenital heart disease. 总被引:3,自引:1,他引:2 下载免费PDF全文
STUDY OBJECTIVE--The aim was to examine if there is an effect of fathers' age and of birth order on the occurrence of congenital heart disease. DESIGN--This was a hospital based case-referent study including use of birth defects surveillance data. SUBJECTS--Subjects were 497 cases of congenital heart disease aged between 3 months and 5 years, born in Beijing and Hebei Province, China; 6222 children without congenital heart disease serve as reference baseline. MEASUREMENTS AND MAIN RESULTS--With stratified analysis and logistic regression analyses, congenital heart disease was found to be associated with fathers' age less than 25 years (odds ratio 2.63), independent of mothers' age and of birth order. There was also evidence to show a higher birth order effect on the occurrence of congenital heart disease independent of parental ages. CONCLUSION--Higher birth order and fathers aged less than 25 years were both independently associated with some categories of congenital heart disease and with congenital heart disease overall. 相似文献
69.
70.
新生鼠和成年鼠脑7种微量元素含量的比较 总被引:1,自引:0,他引:1
利用高频电感耦合等离子体原子发射光谱法(ICP-AES)测定Sprunge-Dawley大鼠新生期大脑皮层、海马、小脑、间脑和脑桥等部位的锌、铁、铜、锰、铬、锶、钼等7种微量元素的含量,并与成年动物做了比较。结果表明:(1)新生期大鼠全脑7种微量元素含量的多寡依次为:锌、铁、铬、锶、锰、铜、钼;成年期时钢跃居第四位,总含量低于新生期。(2)脑内不同部位微量元素的含量不同。新生大鼠海马和小脑内多数元素含量高于其他脑区,钼在间脑和海马中含量较高。成年鼠皮层、海马微量元素含量较高,皮层内铜、锶、钼含量最低。 相似文献