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21.
人肺腺癌细胞分化相关基因cDNAs的克隆   总被引:2,自引:0,他引:2  
在用10-5 mol/L全反式维甲酸(RA)诱导人肺腺癌细胞系GLC-82分化的基础上,以M13噬菌粒pSPORT1为载体,应用定向克隆技术,分别构建了未经RA诱导和RA诱导1d及4d细胞的3个cDNA文库.以含重组子的诱导文库单链DNA为靶标(Target)同未诱导文库的cDNA驱除子(Driver)进行消减杂交,富集RA特异性单链DNA,将富集的单链DNA回复为双链后转化感受态菌,建立细胞诱导分化过程中活化表达基因的cDNA消减文库,得到124个cDNA消减克隆.经同源性分析和与文库总cDNA作Southern印迹杂交,进而与RA诱导前后细胞的RNA作Northern印迹杂交,筛选出2个(RA5,RA28)诱导后呈早期瞬时表达和1个(RA42)呈早期并持续表达的cDNA克隆,cDNA全长分别为1.8,1.5和0.7kb.序列测定及初步功能分析结果表明,RA5,RA28和RA42这3个首次报道的序列,可能是人肺腺癌细胞分化相关基因的cDNA克隆.  相似文献   
22.
王华东  曹文杰  张民  付振帅  刘道营  李耀胜 《生物磁学》2013,(25):4929-4931,4912
目的:早期液体复苏对感染性休克患者血流动力学的影响。方法:选取2012年2月-2013年2月我院ICU收治的26例感染性休克患者作为研究对象,随机分为对照组和试验组,各13例。两组患者均采用PICCO监测,并根据早期复苏目标导向(Earlygoaldirectedtherapy,EGDT)进行早期液体复苏治疗。对照组和试验组复苏液分别为林格液和6%羟乙基淀粉130/0.4氯化钠溶液。分别于复苏开始时(Oh)、8h和24h收集患者的血流动力学参数。结果:两组患者CO及PAWP水平均随着时间的延长下降,而CI、CVP及SVR水平均随着时间的增加上升。除对照组CI外,与开始复苏(oh)相比较试验组和对照组的C0、CI、CVP、SVR及PAWP与开始复苏(O小时)相比较均有显著差异(P值均〈0.05)。经重复测量资料的.方差分析进行比较发现,与对照组相比较,试验组CVP和SVR上升水平及PAWP下降水平明显,差异具有统计学意义(P值均〈0.05)。结论:感染性休克患者使用6%羟乙基淀粉130/0.4氯化钠溶液进行复苏,能更好的改善患者的血流动力学指标。  相似文献   
23.
Multi-drug-resistant bacteria pose a significant threat to public health. The role of the environment in the overall rise in antibiotic-resistant infections and risk to humans is largely unknown. This study aimed to evaluate drivers of antibiotic-resistance levels across the River Thames catchment, model key biotic, spatial and chemical variables and produce predictive models for future risk assessment. Sediment samples from 13 sites across the River Thames basin were taken at four time points across 2011 and 2012. Samples were analysed for class 1 integron prevalence and enumeration of third-generation cephalosporin-resistant bacteria. Class 1 integron prevalence was validated as a molecular marker of antibiotic resistance; levels of resistance showed significant geospatial and temporal variation. The main explanatory variables of resistance levels at each sample site were the number, proximity, size and type of surrounding wastewater-treatment plants. Model 1 revealed treatment plants accounted for 49.5% of the variance in resistance levels. Other contributing factors were extent of different surrounding land cover types (for example, Neutral Grassland), temporal patterns and prior rainfall; when modelling all variables the resulting model (Model 2) could explain 82.9% of variations in resistance levels in the whole catchment. Chemical analyses correlated with key indicators of treatment plant effluent and a model (Model 3) was generated based on water quality parameters (contaminant and macro- and micro-nutrient levels). Model 2 was beta tested on independent sites and explained over 78% of the variation in integron prevalence showing a significant predictive ability. We believe all models in this study are highly useful tools for informing and prioritising mitigation strategies to reduce the environmental resistome.  相似文献   
24.
目的建立心脏特异表达LMNAE82K转基因小鼠,为研究LMNAE82K与心肌病发病机制的关系提供工具动物。方法把LMNAE82K基因插入α-MHC启动子下游,构建转基因表达载体,显微注射法建立C57BL/6JLMNAE82K转基因小鼠,PCR鉴定转基因小鼠的基因型,采用Western Blot鉴定LMNAE82K在心脏组织中的表达,H&E染色和超声检测转基因小鼠心脏的病理改变。结果建立了2个心脏组织特异表达LMNAE82K的转基因小鼠品系。超声检查显示转基因小鼠心室壁变薄,收缩期容积和舒张期容积增加,射血分数及短轴缩短率降低。结论LMNAE82K转基因小鼠具有LMNAE82K引起的家族性扩心病有类似的病理变化,为研究LMNAE82K与心肌病发病机制的关系的研究提供了有价值的疾病动物模型。  相似文献   
25.
26.
Molecular phylogeny and divergence times of drosophilid species   总被引:17,自引:15,他引:17  
The phylogenetic relationships and divergence times of 39 drosophilid species were studied by using the coding region of the Adh gene. Four genera--Scaptodrosophila, Zaprionus, Drosophila, and Scaptomyza (from Hawaii)--and three Drosophila subgenera--Drosophila, Engiscaptomyza, and Sophophora--were included. After conducting statistical analyses of the nucleotide sequences of the Adh, Adhr (Adh-related gene), and nuclear rRNA genes and a 905-bp segment of mitochondrial DNA, we used Scaptodrosophila as the outgroup. The phylogenetic tree obtained showed that the first major division of drosophilid species occurs between subgenus Sophophora (genus Drosophila) and the group including subgenera Drosophila and Engiscaptomyza plus the genera Zaprionus and Scaptomyza. Subgenus Sophophora is then divided into D. willistoni and the clade of D. obscura and D. melanogaster species groups. In the other major drosophilid group, Zaprionus first separates from the other species, and then D. immigrans leaves the remaining group of species. This remaining group then splits into the D. repleta group and the Hawaiian drosophilid cluster (Hawaiian Drosophila, Engiscaptomyza, and Scaptomyza). Engiscaptomyza and Scaptomyza are tightly clustered. Each of the D. repleta, D. obscura, and D. melanogaster groups is monophyletic. The splitting of subgenera Drosophila and Sophophora apparently occurred about 40 Mya, whereas the D. repleta group and the Hawaiian drosophilid cluster separated about 32 Mya. By contrast, the splitting of Engiscaptomyza and Scaptomyza occurred only about 11 Mya, suggesting that Scaptomyza experienced a rapid morphological evolution. The D. obscura and D. melanogaster groups apparently diverged about 25 Mya. Many of the D. repleta group species studied here have two functional Adh genes (Adh-1 and Adh-2), and these duplicated genes can be explained by two duplication events.   相似文献   
27.
28.
采用DNA-蛋白质体外吸附的方法研究伴刀豆球蛋白激活小鼠胸腺T淋巴细胞增殖过程中c-myc与核骨架蛋白的结合.实验结果显示,c-myc与核骨架蛋白的结合具有特异性,在淋巴细胞激活过程中c-myc与P34/P36核骨架蛋白及核纤层蛋白结合,并发生动态变化.  相似文献   
29.
采用红外气体分析仪,于2008年10月17-19日连续3个昼夜原位监测了荷木的树干CO_2释放通量、树干温度、木质部液流密度和CO_2浓度.结果表明:树干CO_2释放通量(EA)日变化呈S形曲线,不同径级间差异显著.EA与树干温度呈显著幂函数关系(0.24
Abstract:
By using a Li-820 infra-red CO_2 gas analyzer, an in situ measurement of Schima super-ba stem CO_2 efflux was conducted for three consecutive days from 17 to 19 October 2008. In the meantime, the stem temperature, xylem sap efflux density, and xylem CO_2 concentration were measured. The stem CO_2 efflux had a diurnal variation of "S" pattern, and differed significantly with stem diameter. There was a significant exponential relationship between stem CO_2 efflux and stem temperature (0. 24 < R~2 < 0. 78). The temperature coefficient (b) and regression coeffi-cient (R~2) were higher at nighttime than at daytime, and the Q_(10) value ranged from 2. 01 to 2. 79. The stem CO_2 efflux correlated significantly with the xylem CO_2 concentration, and the best regression curve was cubic (R~2= 0. 48). Excluding the effects of stem temperature, the stem CO_2 efflux showed a significant negative correlation with xylem sap flux density (r =-0.462). Therefore, only using simple temperature function to estimate stem CO_2 efflux would yield a significant error, and xylem sap flux should be taken into consideration in the stem CO_2 emux estimation.  相似文献   
30.
The pathogenetic role of anticardiolipin antibodies (aCLs) in patients with neuropsychiatric systemic lupus erythematosus (NPSLE) without cerebral infarcts remains elusive. Magnetization transfer imaging (MTI) has proved to be a sensitive tool for detecting diffuse microscopic brain damage in NPSLE patients. In this study we examined the correlation between grey and white matter magnetization transfer ratio (MTR) parameters and the presence of IgM and IgG aCLs and lupus anticoagulant in 18 patients with systemic lupus erythematosus and a history of NPSLE but without cerebral infarcts on conventional magnetic resonance imaging. Lower grey matter mean MTR (P < 0.05), white matter mean MTR (P < 0.05), white matter peak location (P < 0.05) and grey matter peak location (trend toward statistical significance) were observed in IgM aCL-positive patients than in IgM aCL-negative patients. No significant differences were found in MTR histogram parameters with respect to IgG aCL and lupus anticoagulant status, nor with respect to anti-dsDNA or anti-ENA (extractable nuclear antigen) status. This is the first report of an association between the presence of aCLs and cerebral damage in grey and white matter in NPSLE. Our findings suggest that aCLs are associated with diffuse brain involvement in NPSLE patients.  相似文献   
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