黑曲霉原生质体诱变选育果胶酶高产菌株

通过UV和NTG诱变筛选获得了2株高产果胶酶突变株。以果胶酶产生菌黑曲霉EIM6为诱变材料,采用1．5％的溶壁酶和1．5％的纤维素酶处理其对教生长期菌丝体2h获得高质量的原生质体。采用UV25S或50μg／mL NTG诱变30min,构建原生质体突变库,经刚果红果胶平板筛选获得果胶酶突变株,通过液体深层培养复筛获得高产突变株EIM6-U11、EIM6-N5,酶活力分别从46598．08、46598．08U／mL提高至68596．57、68879．56U／mL,分别提高了47．21％、47．82％。连续8次传代经发酵测酶活力表明高产突变株EIM6-U11、EIM6-N5具有较高的遗传稳定性。     

汉防己甲素联合顺铂对乳腺癌细胞的作用

目的:汉防己甲素和顺铂联合作用乳腺癌细胞,来提高癌细胞对顺铂的敏感性.方法:运用原子力显微镜对乳腺癌细胞表面的超微结构进行表征;MTr法和流式细胞术检测细胞的生长抑制率和细胞周期变化.结果:顺铂和汉防己甲素分别作用乳腺癌细胞48h IC50值为26.33μmoL/l和5.6μmok/l;联合用药组的IC50值为汉防己甲素2.5μmol/L和顺铂13.32μmol/l,在低浓度的联合用药作用乳腺癌细胞24h细胞膜表面结构被破坏,产生孔洞,作用48h被严重破坏使细胞周期在S比例增加为51.7%±0.30%.结论:提高了癌细胞对抗癌药物的敏感性,联合用药通过改变了细胞膜的结构对癌细胞进行有效杀伤,抑制肿瘤细胞生长.     

以肠道外症状为首发表现的结肠癌47例临床分析

目的:分析以肠道外症状为首发表现的结肠癌临床特征,旨在提高结肠癌诊治水平。方法:收集我院1994年1月至2008年1月间以肠道外症状为首发表现的结肠癌47例,对其临床特点进行回顾性分析。结果:47例以肠道外症状为首发表现的结肠癌中位发病年龄为65岁;贫血症状多见,占78.7%(37/47),长期低热3例,肝转移瘤4例,肺转移瘤2例,皮肌炎1例;肿瘤多发生于右半结肠,占74.5%(35/47);病理类型:乳头状腺癌为主,占61.7%(29/47);Dukes分期:B期占44.7%(21/47),C期占42.6%(20/47);结肠镜是重要诊断方法,结肠镜与钡灌肠有互补优势;手术是主要治疗手段,综合治疗可延长患者生存期。结论:以肠道外症状为首发表现的结肠癌以贫血多见,病变多位于右半结肠,结肠镜是主要确诊方法,以手术为主的综合治疗可改善患者预后。     

以肠道外症状为首发表现的结肠癌47例临床分析

目的:分析以肠道外症状为首发表现的结肠癌临床特征,旨在提高结肠癌诊治水平.方法:收集我院1994年1月至2008年1月间以肠道外症状为首发表现的结肠癌47例,对其临床特点进行回顾性分析.结果:47例以肠道外症状为首发表现的结肠癌中位发病年龄为65岁;贫血症状多见,占78.7％(37/47),长期低热3例,肝转移瘤4例,肺转移瘤2例,皮肌炎1例;肿瘤多发生于右半结肠,占74.5％(35/47);病理类型:乳头状腺癌为主,占61.7％(29/47);Dukes分期:B期占44.7％(21/47),C期占42.6％(20/47);结肠镜是重要诊断方法,结肠镜与钡灌肠有互补优势;手术是主要治疗手段,综合治疗可延长患者生存期.结论:以肠道外症状为首发表现的结肠癌以贫血多见,病变多位于右半结肠,结肠镜是主要确诊方法,以手术为主的综合治疗可改善患者预后.     

Production of transgenic tomato plants expressing Cry 2Ab gene for the control of some lepidopterous insects endemic in Egypt

Transgenic tomato (cv. Money maker) over expressing Bt (Cry 2Ab) gene was produced using Agrobacterium-mediated transformation method. Molecular and biochemical analysis confirmed the expression and integration of the transgene into tomato genome. Obvious effects of Cry 2Ab were judged by the mortality of the American bollworm Helicoverpa armigera (Hübner) and the potato tuber moth Phthorimaea operculella (Zeller) when fed on Bt tomato. These results indicate that a significant amount of Bt protein was present in all of the transgenic lines and that plants expressing Cry 2Ab gene could be used for management of the target lepidopteran insect pests endemic in Egypt.     

Variation between strains of the cyanobacterium Microcystis aeruginosa isolated from a Portuguese river

AIMS: The aim of this study was to investigate toxicological differences between strains of the cyanobacterium Microcystis aeruginosa isolated from a potable water supply in the north of Portugal over a 2-month period. METHODS AND RESULTS: Twenty-six strains of M. aeruginosa were isolated, grown in pure culture, and tested using a range of techniques including matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), ELISA and a PCR procedure targeting the genes implicated in the production of toxic microcystins. There was considerable variation with respect to the amounts of microcystin produced by each of the strains as measured by ELISA, with values ranging from 0.02 to 0.53% dry weight. The results of the MALDI-TOF MS analysis demonstrated the presence of several chemically distinct forms of microcystin as well as aeruginosins, anabaenopeptins and several other unidentified peptide-like compounds. CONCLUSIONS: The growth of individual strains that comprise bloom populations, with unique 'chemotypes' can potentially be an important factor affecting the toxicity of bloom populations. Molecular probes, targeting the genes responsible for microcystin production were shown to be useful for distinguishing between toxic and nontoxic strains and showed good agreement with the results obtained from the other analyses. SIGNIFICANCE AND IMPACT OF THE STUDY: The results of this study show that the analysis of cyanobacterial bloom populations at the subspecies (strain) level can potentially provide important information regarding the toxin-producing potential of a cyanobacterial bloom and could be used as an 'early warning' for toxic bloom development.     

A biological and molecular characterization of some Egyptian barley genotypes which are resistant to net blotch disease

A survey for resistance against net blotch disease (caused by Pyrenophora teres) was performed on some Egyptian barley landraces and some selected resistance and susceptible standard German barley genotypes. The results indicated that most of the Egyptian barley landraces are extremely resistant to the disease. Molecular analysis using RAPD and AFLP showed unique banding profiles for the different genotypes, and specific AFLP markers for the Egyptian genotypes were identified. The effectiveness of RAPD and AFLP for identifying different barley genotypes of different origins and with different reactions against P. teres was discussed. The results of the biological evaluation and molecular characterization done in this study can be seen as the starting point needed to identify the valuable net blotch resistant Egyptian barley germplasm at both the phenotype and genotype levels and draw the attention of breeders and banks of natural plant genetic resources towards this valuable yet neglected germplasm.     

杂色鲍头触角的显微与亚显微结构

本文采用光镜和电镜方法,研究了杂色鲍(Haliotisdiversicolor)头触角的显微和亚显微结构。结果表明,杂色鲍头触角的表皮布满乳头状突起,突起表面布满微绒毛,顶端具纤毛。头触角作为重要的感觉器官之一,具触觉兼嗅觉功能,其上皮为特殊的感觉上皮,其组成细胞主要包括三种类型:支持细胞、感觉细胞、腺细胞。头触角表皮之下的成分为平滑肌纤维和疏松结缔组织,疏松结缔组织里含胶原纤维、成纤维细胞、肥大细胞、微孔细胞、变形细胞等成分。     

胃溃疡对大鼠胃中HAP1表达的影响

建立冰乙酸性大鼠胃溃疡模型,采用ABC法进行免疫组织化学染色,观察并探讨胃溃疡对胃壁中HAP1(huntingtin as-soc iated protein 1,HAP1)表达的影响。结果溃疡组大鼠胃壁中HAP1阳性细胞数目及光密度与正常进食的大鼠相比显著增多。