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1.
Bing Xia Haiping Ke Wei Jiang Masayori Inouye 《The Journal of biological chemistry》2002,277(8):6005-6011
The 5'-end region of cspA mRNA contains a Cold Box sequence conserved among several cold-shock mRNAs. This region forms a stable stem-loop structure followed by an AU-rich sequence. Here we show that the Cold Box region is essential for the normal scale of cspA mRNA induction after cold shock because a deletion of the stem-loop significantly destabilizes the mRNA and reduces the cold shock-induced cspA mRNA amount by approximately 50%. The AU-rich track, however, slightly destabilizes the mRNA. The integrity of the stem is essential for the stabilizing function, whereas that of the loop sequence is less important. Overexpression of a mutant cspA mRNA devoid of both the AUG initiation codon and the coding sequence results in a severe growth inhibition at low temperature along with a derepression of the chromosomal cspA expression. Furthermore, the overexpressed RNA is stably associated with the 30 S and 70 S ribosomes. Our results demonstrate that the AUG initiation codon and the coding region containing the downstream box are not required for cspA mRNA to bind ribosomes and that the 5'-untranslated region by itself has a remarkable affinity to ribosomes at low temperature. 相似文献
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W J Allard C D Cheli D L Morris J Goldblatt Y Pierre L Kish Y Chen J Dai R L Vessella D W Chan M K Schwartz Z Zhou K K Yeung 《The International journal of biological markers》1999,14(2):73-83
We conducted a multicenter evaluation of the analytical and clinical performance of the automated Bayer Immuno 1 complexed PSA (cPSA) assay, and compared assay performance to the Bayer Immuno 1 PSA assay. We sought to determine whether measurements of cPSA could be of clinical utility in the management of patients with prostate cancer. Results of the 10-day imprecision across three evaluation sites produced total CV < 2.50% and an analytical sensitivity of 0.02 microgram/L. There was an increased trend in clinical sensitivity for prostate cancer with increasing stage of disease (71-86%). Clinical specificity for patients with benign urogenital disease was 74.8%, and for other nonprostate diseases ranged from 91.1-100%. Retrospective serial monitoring of 155 patients with prostate cancer demonstrated concordance of cPSA measurements to clinical status for 97% of the patients analyzed. Results from the clinical studies using the Bayer Immuno 1 cPSA assay were comparable to results obtained with the Bayer Immuno 1 PSA assay. The Bayer Immuno 1 cPSA assay demonstrates analytical performance and clinical effectiveness in the management of prostate cancer patients during the course of disease and therapy. 相似文献
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Cory Bystrom Shijun Sheng Ke Zhang Michael Caulfield Nigel J. Clarke Richard Reitz 《PloS one》2012,7(9)
Measurement of insulin-like growth factor-1 (IGF-I) has utility for the diagnosis and management of growth disorders, but inter-assay comparison of results has been complicated by a multitude of reference standards, antibodies, detection methods, and pre-analytical preparation strategies. We developed a quantitative LC-MS method for intact IGF-I, which has advantages in throughput and complexity when compared to mass spectrometric approaches that rely on stable isotope dilution analysis of tryptic peptides. Since the method makes use of full-scan data, the assay was easily extended to provide quantitative measurement of IGF-II using the same assay protocol. The validated LC-MS assay for IGF-I and IGF-II provides accurate results across the pediatric and adult reference range and is suitable for clinical use. 相似文献
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Lexical gap in cQA search, resulted by the variability of languages, has been recognized as an important and widespread phenomenon. To address the problem, this paper presents a question reformulation scheme to enhance the question retrieval model by fully exploring the intelligence of paraphrase in phrase-level. It compensates for the existing paraphrasing research in a suitable granularity, which either falls into fine-grained lexical-level or coarse-grained sentence-level. Given a question in natural language, our scheme first detects the involved key-phrases by jointly integrating the corpus-dependent knowledge and question-aware cues. Next, it automatically extracts the paraphrases for each identified key-phrase utilizing multiple online translation engines, and then selects the most relevant reformulations from a large group of question rewrites, which is formed by full permutation and combination of the generated paraphrases. Extensive evaluations on a real world data set demonstrate that our model is able to characterize the complex questions and achieves promising performance as compared to the state-of-the-art methods. 相似文献
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Three new species, Tambocerus dentatus, T. longicaudatus and T. robustispinus spp. n. from southern China, are described and illustrated. A checklist and distribution to the Tambocerus species from China is provided together with a key for their separation. 相似文献