I. Immunosurveillance and tumorigenesis in BALB/c mice—1. Early reactive state in mesenteric granulomas

The cellular immune response in BALB/c mice mesenteric granulomas (MG) was analysed by the means of functional ultrastructure and the assessment of the presence or absence of asynchronous plasma cells in situ.

Results from this study establish: (a) the sequential events involved in the genesis of the oil-induced granulomas, (b) the weak T-cellular immune response and the almost absence of these cells in mitosis, (c) the presence of asynchronous plasma cells of type II was found in mice Nos. 8, 9, 10 and 11 and they were considered to be plasma cell mutants of temporary type, to indicate the first step of this cell alienation in tumorigenesis, (d) the high ratio of peritoneal macrophages was found and connected with what is known about it in the literature. It was speculated that the supraoptimal presence of peritoneal macrophages could have been responsible for the appearance of plasma cell mutants and (e) four morphological types of macrophages have been found in this animal's oil-induced MG, representing different stages of the monocyte transformation in situ.     

与HEp-2细胞粘附现象相关的大肠杆菌O157基因的发现

将产志贺毒素大肠杆菌O157：H7菌株97094培养于含有不同质量浓度的萘啶酮酸(nalidixie acid，NA)的麦康凯(MacConkey)琼脂平板上，获得对NA有抗性的菌株。用含有自杀性质粒pRT733的供体菌SM10λpir(携带转座子TnphoA)和抗萘啶酮酸的97094菌株做接合试验，使转座子TnphoA转入受体菌97094，经过约200个接合试验，有503个菌株在含有Km、NA、XP的LB琼脂平板上形成蓝色菌落，说明在这些菌株中形成了phoA融合基因,并能表达phoA基因。在这503个Km^r，NA^r变异体中，有6株完全失去了对HEp-2细胞的局灶型粘附(local adherence,LA)现象。对构建的6株大肠杆菌O157 TnphoA变异体，克隆TnphoA及其两侧的大肠杆菌O157 DNA序列，用根据TnphoA融合接点处的phoA的DNA序列设计合成的寡核苷酸引物，对各克隆中TnphoA上游的大肠杆菌O157的DNA片段部分进行测序，测序结果做BLAST搜索，发现有4个变异体的TnphoA插入到已知的大肠杆菌O157紧密素基因eae中，有2个变异体的TnphoA分别插入到eae之外的核苷酸序列中，分别插入到一个功能未知的菌毛分子伴侣基因和一个功能未知的Z4182基因的上游。这项研究表明，除紧密素外，大肠杆菌O157尚有其他因子参与对真核细胞的粘附。     

西花蓟马对不同颜色粘卡的嗜好及其诱虫效果

西花蓟马对14种不同颜色粘卡的嗜好及其诱虫量比较试验数据显示,颜色较浅的1号和4号黄色粘卡诱虫效果显著高于12号粘卡（市售黄板）.在测定颜色范围内,随黄色程度变浅诱集效果逐渐增强,蓝色粘卡从9号开始随颜色变深或变浅,诱虫效果均逐渐降低,黄色1号的诱虫效果最好,与黄色4号和蓝色9号粘卡的效果差异不显著.结果表明市场上出售的蓝色和黄色均不是诱集效果最好的颜色或亮度,以前没有黄色粘卡对西花蓟马诱集效果的报道.     

海南香蕉枯萎病菌营养亲和群研究

从海南省各市县香蕉种植区采集发病的香蕉和粉蕉植株近地面茎段维管束病变的样本,经分离纯化获14个单孢菌株。经寄主致病性测定表明:粉蕉分离物皆为香蕉枯萎病菌1号生理小种,香蕉分离物则为4号生理小种。利用氯酸钾诱变这14个枯萎菌株共产生104个抗氯酸盐突变体,诱发获得67个nit突变株,其中nitl型58株,nitM型6株,nit3/nit8型3株。将获得的nit突变株做营养亲和性配对反应,可将14个菌株分为2个亲和群,其中VCG1包括7个菌株,且全为1号生理小种,VCG2则由7个4号小种菌株组成。     

基于颜色特征的稻种霉变检测算法

根据机器视觉检测杂交水稻种子质量的要求，对单粒、静态稻种图像进行霉变分析识别。比较了提取颜色特征的3种方法，研究了基于颜色特征的稻种霉变检测算法，经试验验证，该算法对正常稻种、轻度霉变稻种、严重霉变稻种的检测准确率分别为92％、95％、83％。     

9 种药剂对温室彩椒西花蓟马的田间防效评价

针对西花蓟马对京郊保护地彩椒危害严重的现况,选取市售的0.6% 苦参碱水剂、0.5% 印楝素乳油、1% 虫菊·苦参碱微囊悬乳剂、1.5% 除虫菊素水乳剂、7.5% 鱼藤酮乳油等5 种植物源药剂和1% 甲氨基阿维菌素苯甲酸盐微乳剂、1.8% 阿维菌素乳油、2% 高氯·甲维盐微乳剂、6% 乙基多杀菌素悬乳剂等4 种非植物源药剂,进行田间药效筛选。结果表明：在试验观察期,施药后1、3、7 d,5 种植物源药剂校正防效由34.8%～50.0% 上升至59.2%～68.6%,防效随着处理时间的延长表现出增强的趋势,药效呈现较好的持效性;4 种非植物源药剂在药后3 d 的校正防效均达64% 以上,对西花蓟马表现出较好的速效防治效果,但防效随时间
延长表现出减弱的趋势,施药后第7 天,除1.8% 阿维菌素乳油之外,非植物源药剂的防效均显著低于植物源药剂防效。     

雪莲果营养浆水工艺技术研究

研究雪莲果营养浆水工艺技术,为雪莲果深加工提供理论依据。以新鲜雪莲果为原料,针对雪莲果在加工过程中易褐变、易沉淀等实际问题开展深入研究,研究结果表明:100℃杀青6 min雪莲果出汁率达90.1%,颜色为淡黄色;采用食盐0.06%、Vc0.3%、柠檬酸0.3%、时间40 min,雪莲果汁护色效果最佳;采用0.3g/100ml果胶酶+0.3 g/100ml纤维素酶复配处理雪莲果果汁,果汁澄清状态最佳;雪莲果原汁含量20%,柠檬酸含量0.1%,白砂糖含量9%,蜂蜜含量0.5%的雪莲果营养浆水口感风味及状态最佳。     

Development and characterization of rifampicin-resistant mutants from high virulent strains of Flavobacterium columnare

Flavobacterium columnare is divided into three genetic groups or genomovars, genomovar II being highly virulent for channel catfish. A modified live vaccine is currently available to prevent columnaris disease under the licensed name Aquavac‐Col^®. The strain of F. columnare used to generate the avirulent rifampicin‐resistant mutant used in Aquavac‐Col^® belonged to genomovar I, the less virulent group towards channel catfish. In this study, we describe the generation and characterization of rifampicin‐resistant mutants from genomovar II strains. A total of 13 new mutants were obtained, and eight of them (two from each parent strain) were genetically and phenotypically characterized. Highly conserved regions within the ribosomal operons were identical between parent and mutant strains. Genetic differences between mutants and their parent strains were revealed by amplified fragment length polymorphism (AFLP). Genetic changes were distinctive among different mutants. Analysis of the lipopolysaccharide (LPS) showed that while some mutants lacked a few molecular bands of the LPS, some exhibited the same LPS profiles as their parent strains. Comparison between immunogenic proteins from mutants and parents was carried out by immunoblot analysis and further confirmed the uniqueness of individual mutants. A complete set of rifampicin‐resistant mutants with different genetic and immunogenic properties from the highly virulent genomovar II has been created. These mutants may have the potential of becoming vaccine candidates against columnaris disease.     

基于颜色特征的加工番茄叶片氮素评价初步研究

利用数码相机获取加工番茄地上部分彩色图像,通过图像处理软件提取RGB及其组合的颜色特征值,同时与氮素指标叶片叶绿素含量、SPAD值、叶片含氮量及单株吸氮量作回归分析,根据统计性检验,有相当数量的颜色特征与4个氮素指标呈较高的相关性,相关系数达到r=0.7以上.综合筛选出的颜色特征指标,结合地面覆盖度与氮素营养指标建立以叶片含氮量为应变量的估算模型.经模型校验,其预测值与实测值在n=15,P＜0.01水平上达r=0.8以上的极显著相关.因此,可依据颜色特征参数通过建立相应的统计模型进行加工番茄叶片氮素含量的评价,进而为加工番茄氮素营养诊断提供依据.     

壳聚糖后处理染色单板的耐水和耐光颜色稳定性

酸性染料染色后的木材单板耐水性较差,容易褪色。采用单板染色后涂刷壳聚糖的方法,固色效果优异,单板本身变色小,能显著地提高染色单板的耐水和耐光稳定性。探讨了不同壳聚糖质量分数、涂刷量、处理方法对染色单板的固色效果。