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1.
Bacillus thuringiensis (Bt), a Gram-positive bacte-rium, produces insecticidal crystal proteins during sporulation. Bt has been used as biopesticides to con-trol a number of insect pests from Lepidoptera, Dip-tera and Hymenoptera and also has become so far the leading gene sources of transgenic plants resistant toinsect pests[1,2]. In China, the use of Bt cotton began in 1997 in Hebei, Shandong and Henan provinces, etc. and rapidly increased to more than 2 million ha in 2002, which is effe…  相似文献   
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Genetic mapping provides a powerful tool for quantitative trait loci (QTL) analysis at the molecular level. A simple sequence repeat (SSR) genetic map containing 590 markers and a BCI population from two cultivated tetraploid cotton (Gossypium hirsutum L.) cultivars, namely TM-1 and Hai 7124 (G. barbadense L.), were used to map and analyze QTL using the composite interval mapping (CIM) method. Thirty one QTLs, 10 for lobe length, 13 for lobe width, six for lobe angle, and two for leaf chlorophyll content, were detected on 15 chromosomes or linkage groups at logarithm of odds (LOD)≥2.0, of which 15 were found for leaf morphology at LOD≥3.0. The genetic effects of the QTL were estimated. These results are fundamental for marker-assisted selection (MAS) of these traits in tetraploid cotton breeding.  相似文献   
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重视每个建设环节铸造微生物学国家精品课程*   总被引:1,自引:1,他引:0  
国家精品课程建设是提高高校教育质量的重要举措,是涉及教师、学生、教材、教学技术手段、教育思想和教学过程管理的系统工程。介绍了我们在微生物学国家级精品课程建设过程中在师资队伍建设,教学内容和课程体系改革,注重使用先进的教学方法和手段,重视教材建设,理论教学与实践教学并重等各个课程建设环节的做法与体会。  相似文献   
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高灵敏假单胞菌铁载体的平板检测方法   总被引:6,自引:1,他引:5  
CAS蓝色检测平板是一种筛选、检测各类细菌铁载体的常用方法,而蔗糖-天冬酰氨培养基被用于假单胞菌产铁载体规律的研究。用天冬氨酸替代天冬酰氨,将CAS蓝色检测液与蔗糖-天冬氨酸培养基(MSA培养基)相结合,得到一种改进的MSA-CAS检测平板。通过对假单胞菌属7个种8个株进行荧光与非荧光铁载体检测方面的比较研究,结果表明MSA-CAS检测平板假单胞菌铁载体的检测灵敏度比通用CAS检测平板高,而且在检测荧光铁载体方面具有荧光背景低、荧光铁载体晕圈明显和晕圈与背景的对比度大的优点。  相似文献   
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采用pH6.8的磷酸缓冲液代替通用CAS固体检测培养基中的MM9缓冲体系,不加哌嗪二乙醇磺酸,得到颜色稳定、检测效果明显、配制方便,适合高产铁载体细菌筛选与检测的新型检测平板。根据CAS检测液连续吸收光谱比较分析结果,将CAS液体定量检测体系中的检测波长由630nm改为680nm,可以克服OD630读数偏高、易受干扰的问题,而且OD680与铁载体浓度线性关系不变,但采用OD680检测不同细菌产铁载体能力的差异更为明显,因此提高了CAS  相似文献   
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We evaluate comparative toxicity of malathion in the two populations of the grasshopper Oxya chinensis, collected from Daixian and Fanshi of Shanxi province, China. General esterases and acetylcholinesterase (ACHE) from the two populations were characterized and compared. LD50 of the Daixian population (7.58 μg/g body weight) was 2.02-fold higher than that of the Fanshi population (3.75μg/g body weight). General esterase-specific activities in the Daixian population were 1.91,130 and 1.85-fold higher than those in the Fanshi population, when α-NA, α-NB and β-NA were used as a substrate, respectively. Kinetic studies of general esterase showed that Vmax values of general esterases hydrolyzing α-NA,α-NB and β-NA in the Daixian population were 2.15-, 1.12-, and 1.47-fold, respectively, higher than those in the Fanshi population. The AChE activity of the Fanshi population was 1.54-fold higher than that of the Daixian population. Kinetic analysis of AChE showed that significant differences were presented between the two populations in the Km values; and the Vmax value in the Fanshi population was higher than that in the Daixian population. Inhibition studies of AChE indicated that AChE from the Daixian population was 2.56-, 2.80-, and 2.29-fold less sensitive to inhibition by paraoxon, chlorpyrifos-oxon, and demeton-S-methyl, respectively, than that from the Fanshi population. These biochemical characterizations of general esterases and AChE were consistent with malathion bioassay in the two populations. It is inferred that the reduced sensitivity of altered AChE and increased general esterase activities play an important role in the differences of insusceptibility of Oxya chinensis to malathion between the two populations.  相似文献   
8.
For successful therapy, hepatocellular carcinoma (HCC) must be detected at an early stage. Herein, we used a proteomic approach to analyze the secretory/releasing proteome of HCC tissues to identify plasma biomarkers. Serum-free conditioned media (CM) were collected from primary cultures of cancerous tissues and surrounding noncancerous tissues. Proteomic analysis of the CM proteins permitted the identification of 1365 proteins. The enriched molecular functions and biological processes of the CM proteins, such as hydrolase activity and catabolic processes, were consistent with the liver being the most important metabolic organ. Moreover, 19% of the proteins were characterized as extracellular or membrane-bound. For validation, secretory proteins involved in transforming growth factor-β signaling pathways were validated in plasma samples. Alphafetoprotein (AFP), metalloproteinase (MMP)1, osteopontin (OPN), and pregnancy-specific beta-1-glycoprotein (PSG)9 were significantly increased in HCC patients. The overall performance of MMP1 and OPN in the diagnosis of HCC remained greater than that of AFP. In addition, this study represents the first report of MMP1 as a biomarker with a higher sensitivity and specificity than AFP. Thus, this study provides a valuable resource of the HCC secretome with the potential to investigate serological biomarkers. MMP1 and OPN could be used as novel biomarkers for the early detection of HCC and to improve the sensitivity of biomarkers compared with AFP.  相似文献   
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