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Leena Rao 《Resonance》2007,12(8):65-75
This article deals with various ‘supported’ acid catalysts developed as alternatives for the conventional ones in organic synthesis. They have advantages such as producing less toxic waste and using less energy.  相似文献   
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教育评论形态是指教育评论的形式和状态,它是教育评论学研究的理论问题之一.教育评论形态的划分依人们视点的不同而万紫千红.按教育评论主体的不同可以分为:大众教育评论、专家教育评论、行家教育评论.大众教育评论是基础;专家教育评论是基于大众教育评论基础上的专业性评论,是行家教育评论的基础;而行家教育评论则是立足于大众教育评论,建立在专家教育评论之上的"教育评论金字塔"塔顶.  相似文献   
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This paper describes a method for the quantitative detection of cells expressing BlaC, a β-lactamase naturally expressed by Mycobacterium tuberculosis, intended for the diagnosis of tuberculosis. The method is based on the compartmentalization of bacteria in picoliter droplets at limiting dilutions such that each drop contains one or no cells. The co-encapsulation of a fluorogenic substrate probe for BlaC allows the quantification of bacteria by enumerating the number of fluorescent drops. Quantification of 10 colony forming units per milliliter is demonstrated. Furthermore, the encapsulation of single cell in drops maintains the specificity of the detection scheme even when the concentration of bacteria that do not express BlaC exceeds that expressing BlaC by one million-fold.  相似文献   
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Radiation therapy has been widely applied in cancer treatment. However, it often causes thrombocytopenia (deficiency of white blood cells) as an adverse effect. Recombinant human interleukin-6 (rhIL-6) has been found to be a very effective way against this thrombocytopenia, but IL-6 has low stability in blood, which reduces its efficacy. To increases the stability and half-life of rhIL-6, it was modified by polyethylene glycol (PEG). The pharmacokinetics and the tissue distribution of PEG-rhIL-6 labeled with 125I were examined after subcutaneous injection in rats. The pharmacokinetic pattern of PEG-rhIL-6 was defined with linear-kinetics, and we fitted a one-compartment model with half-lives of 10.44–11.37 h (absorption, t 1/2K a) and 19.77–21.53 h (elimination, t 1/2Ke), and peak concentrations at 20.51–21.96 h (t peak) in rats. Half-lives and t peak of PEG-rhIL-6 were longer than those of rhIL-6 previously reported. In the present study, for deposition of PEG-rhIL-6 in rats, the tissue distribution examination showed that blood was the major organ involved, rather than liver. However, as to the elimination of PEG-rhIL-6, the major organ was the kidney. The excretion fraction of the injection dose recovered from urine was 23.32% at 192 h after subcutaneous administration. Less than 6% of PEG-rhIL-6 was eliminated via the feces at 192 h. These results indicate that PEG-rhIL-6 is a good candidate drug formulation for patients with cancer.  相似文献   
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Science & Education - Like all SSI, the COVID-19 pandemic requires decisions that are contentious, involve scientific thinking, and vary across social groups. This investigation determined how...  相似文献   
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