Flow karyotypes and chromosomal DNA contents of genus Triticum species and rye (Secale cereale)

The flow cytometry and chromosome imaging method were jointly used for analyzing genome content and chromosomal DNA content of hexaploid wheat (AABBDD), hexaploid triticale (AABBRR), tetraploid wheat (AABB), and AA, BB, DD genome donors and RR genome rye. Their genome sizes were 34.4 pg, 40.9 pg, 26.2 pg, 12.1 pg, 13.7 pg, 10.5 pg, and 16.9 pg, respectively. The 2C nuclear DNA content of BB genome donor with 13.7 pg was the highest value among the other genome donors, AA or DD. The genome content of tetraploid wheat, unlike hexaploid wheat or hexaploid triticale, was larger than the sum of the genomes of AA and BB genome donors. The DNA content of each chromosome ranged from 1.22 pg in DD genome donor to 2.61 pg in rye. Each chromosome peak was divided into three to four groups. Only one chromosome was included in the highest chromosomal DNA peak in hexaploid wheat, tetraploid wheat, DD genome donor and rye but two chromosomes in AA, BB genome donors, and hexaploid triticale. Correlation between 2C nuclear DNA content and chromosome density volume was the highest value compared with the other chromosomal parameters of chromosome area, or chromosome length.     

Ventricular rate smoothing for atrial fibrillation: a quantitative comparison study.

AIMS: To quantitatively compare the ventricular rate-smoothing (VRS) effects of different ventricular pacing (VP) protocols for atrial fibrillation (AF). METHODS AND RESULTS: Using a recently developed open-source model that can simulate the ventricular response in AF and VP, the performance of fixed-rate pacing and four previously published VRS algorithms were assessed by the mean RR (mRR), the root mean square of successive RR differences (RMSSD), the percentage of ventricular senses (VS%), and the percentage of short RR intervals (sRR%). All pacing protocols cause rate-dependent reduction of RMSSD, VS%, and sRR% with or without shortening of mRR compared to spontaneous AF. Fixed-rate pacing was more sensitive to the intrinsic rate than the VRS algorithms. The performance was generally comparable between different VRS algorithms, although higher mRR and VS% can be achieved at the expense of larger RMSSD and sRR%. CONCLUSION: The effect of VP on ventricular rhythm in AF depends on both intrinsic rate and the aggressiveness of the pacing protocol. Adequate rate control is necessary for effective operation of the VRS algorithm. Choosing VRS algorithm should balance between the beneficial effects of rate regularization and the negative effects of increasing heart rate and percentage of VP.     

用SYBR Green I实时逆转录-聚合酶链反应定量检测人、小鼠精子中CatSper1 mRNA

目的:建立并优化SYBR GreenI实时RT-PCR体系,定量检测人、小鼠成熟精子中的CatSper1 mRNA。方法:用TRIzol分别提取人、小鼠成熟精子中的总RNA,逆转录后用SYBR GreenI实时PCR定量检测CatSper1 mRNA。SYBR GreenI实时PCR采用普通PCR试剂,加入SYBR GreenI染料,优化退火温度、Mg2+浓度及上、下游引物比例,并在PCR循环时采用四步法以消除引物二聚体的影响。优化完成后用不同浓度的精子cDNA为模板做标准曲线,以检测SYBR GreenI实时PCR的扩增效率。结果:定量检测CatSper1 mRNA的SYBR GreenI实时PCR体系适宜退火温度、Mg2+浓度及上、下游引物比例分别为63℃、3.0mmol/L和1∶1,四步法中采集荧光的温度为88℃。优化后用人和小鼠精子cDNA为模板做标准曲线分别为Y=-3.402log(X)+25.99和Y=-3.409log(X)+24.09,扩增效率分别为96.8%和96.5%,可定量检测人、小鼠成熟精子中的CatSper1 mRNA。结论:用普通的逆转录及PCR系统和试剂,建立了一种方便、廉价、可靠的SYBR GreenI实时荧光定量RT-PCR系统,可用于人、小鼠精子中CatSper1 mRNA定量检测。     

核黄素等抗甲基苄基亚硝胺的致细胞突变作用

采用ＣＨＯ细胞ＨＧＰＲＴ位点突变测定系统观察了核黄素、尼克酰胺和锌等微量营养素对甲基苄基亚硝胺（ＭＢＮＡ）致细胞突变作用的影响。结果表明，在ＲＰＭＩ１６４０培养基中添加核黄素（２．６～１３．０μｍｏｌ／Ｌ）或尼克酰胺（４０～１２０μｍｏｌ／Ｌ）可显著抑制ＭＢＮＡ的致细胞突变作用。联合应用核黄素、尼克酰胺和锌效果更佳。提示：核黄素等微量营养素可能具有阻止细胞癌变的作用，为应用微量营养素干预治疗癌变过程提供了一定的理论依据。     

林县冬贮菜中亚硝酸盐及维生素C的含量分析

对林县食管癌高发区两种冬贮菜中亚硝酸盐和维生素C的动态分析,表明亚硝酸盐含量随蔬菜冬贮时间延长而增加,维生素C含量则逐渐降低,两者成负相关。提示蔬菜冬贮过程中应尽量减少维生素C的破坏。     

消化内镜病毒污染的现状及对策

从乙型肝炎病毒、丙型肝炎病毒和人类免疫缺陷病毒污染情况综述了消化内镜病毒污染的现状，分析了污染的原因以及消化内镜消毒现状。     

低功率电切治疗膀胱肿瘤疗效观察

目的 探讨经尿道膀胱肿瘤低功率电切术的适应症、手术方法及其疗效评估. 方法分析65例经尿道膀胱肿瘤切除术.手术时间10～90 min,平均时间41 min;膀胱穿孔1例,术后冲洗时间1～3 d,平均2 d;导尿管留置时间1～5 d,平均4 d.结果 随访0.5～3 a,48例中肿瘤复发15例,其中原位复发2例,异位多位复发13例.结论 经尿道膀胱肿瘤低功率电切可防止并明显减少闭孔神经反射的发生,具有操作简单,损伤小,出血少、恢复快等优点.     

Search for coloured objects in natural surroundings by people with abnormal colour vision

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.     

隐动脉筋膜蒂的交腿皮瓣修复小腿严重软组织缺损

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。     

大,巨型垂体腺瘤的手术入路选择

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。