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INTRODUCTION Aqueous two-phase system (ATPS) is widely used in biochemistry and biotechnology for purifica- tion of proteins (Diamond and Hsu, 1992; Balasubramaniam et al., 2003), enzymes (Pan et al., 2001; Bim and Franco, 2000), amino acids (Li et al., 2002), antibiotics (Yang et al., 1994; Guan et al., 1994), nucleic acids (Ohlsson et al., 1978; Kimura, 2000), aroma compounds (Marco et al., 2000) and lactic acid (Planas et al., 1998). ATPS is mainly composed of two-incompatible p…  相似文献   
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重视学生整体素质的提高,全面推行素质教育是当前教育界的迫切任务.学生工作在学生的素质教育问题上,能够发挥较大的作用.  相似文献   
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巨大的火成区   总被引:5,自引:0,他引:5  
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Relationship between hyperuricemia and metabolic syndrome   总被引:6,自引:0,他引:6  
Objective: To investigate the relationship between metabolic syndrome and hyperuricemia. Methods: A total of 2 374 subjects who received health examination in our hospital from Jan. 2004 to Dec. 2006 were enrolled in our study. Hyperuricemia is defined as ≥7 mg/dl (in men) or ≥6.0 mg/dl (in women). Metabolic syndrome was defined using AHA/NHLBI (American Heart Association/National Heart, Lung, and Blood Institute) criteria. Results: (1) The overall prevalence of hyperuricemia was 13.10%. The condition was more common in men than in women (19.07% vs 3.42%). (2) Among men, uric acid concentration is statistically significantly positively correlated with waist circumference, blood pressure, and triglyceride. Uric acid is negatively correlated with serum high-density lipoprotein-cholesterol (HDL-C). Uric acid concentration is most strongly correlated with serum triglyceride (r=0.379) and waist circumference (r=0.297). Among women, statistically significant positive correlations were noted for the serum uric acid concentrations with waist circumference, triglyceride and fasting plasma glucose. Serum triglyceride (r=0.329) and waist circumference (r=0.234) are most strongly correlated with uric acid concentrations. (3) Men with hyperuricemia had a 1.634-fold increased risk of metabolic syndrome as compared with those without hyperuricemia odds ratio (OR)=1.634, P=0.000. Women with hyperuricemia had a 1.626-fold increased risk of metabolic syndrome (OR=1.626, P=0.000) as compared with those without hyperuricemia. Conclusion: Hyperuricemia is prevalent among Chinese population. Additionally, serum uric acid is positively associated with metabolic syndrome.  相似文献   
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Infant joint attention has been observed to be related to social-emotional outcomes in at-risk children. To address whether this relation is also evident in typically developing children, 52 children were tested at 12, 15, 24, and 30 months to examine associations between infant joint attention and social outcomes. Twelve-month initiating and responding to joint attention were related to 30-month social competence and externalizing behavior, even when accounting for 15-month temperament ratings, 24-month cognition and language, and demographic variables. These results suggest that, in addition to associations with language and cognition, infant joint attention reflects robust aspects of development that are related to individual differences in the emergence of social and behavioral competence in childhood.  相似文献   
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The longitudinal development of the intraindividual coupling between academic achievement, interest, and self-concept of ability (SCA) was analyzed in a sample of approximately 1,000 children between grades 1 and 12 (ages 6-17). Across all calculated indexes, the average level of coupling was positive. Individuals generally felt competent and interested in domains where they achieve well, and were interested in domains where they perceive their personal strengths. The degree of coupling was the highest between interest and SCA and the lowest between interest and achievement. For all indexes, evidence for an increase in coupling across time was found. Female gender was related to a lower level of coupling. There was evidence for a positive effect of conscientiousness on the amount of coupling.  相似文献   
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目的:探讨TCT(液基薄层细胞学)与阴道镜下活检的吻合程度,分析不同医生的诊断吻合度,最大限度提高TCT作为宫颈癌筛查手段的的准确性。方法:选取2007年2月至2010年9月期间来我院进行妇科体检TCT异常病例3 226人次的TCT诊断报告与阴道镜活检诊断结果进行比较,以病理活检作为最后诊断。结果:三位主治医生中甲的阅片吻合率为73.98%,乙的吻合率为77.04%,丙的吻合率为82.30%,总的吻合率为78.18%,三者间比较差异极显著(χ2=22.42,P〈0.000 1)。结论:1)TCT细胞学检查与传统的细胞学方法相比取材方便,无创,确诊率高,是宫颈癌筛查的重要方法。2)医生经验在诊断过程中起重要作用,加强对医务人员的培养,适时培训是提高TCT确诊率的重要环节。  相似文献   
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厌氧消化技术能够实现废弃物污染防治和综合利用的双重目标,是有机固废处理与处置的发展趋势。对厌氧消化技术处理有机固废的微生物学机理、影响因素以及消化工艺的研究进展进行了综述。  相似文献   
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