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991.
992.
Nitric oxide (NO) a free radical having both cytoprotective as well as tumor promoting agent is formed from l-arginine by converting it to l-citrulline via nitric oxide synthase enzymes. The reaction product of nitric oxide with superoxide generates potent oxidizing agent, peroxynitrite which is the main mediator of tissue and cellular injury. Peroxynitrite is reactive towards many biomolecules which includes amino acids, nucleic acid bases; metal containing compounds, etc. NO metabolites may play a key role in mediating many of the genotoxic/carcinogenic effects as DNA damage, protein or lipid modification, etc. The basic reactions of nitric oxide can be divided as direct effect of the radical where it alone plays a role in either damaging or protecting the cell milieu and an indirect effect in which the byproducts of nitric oxide formed by convergence of two independent radical generating pathways play the role in biological reactions which mainly involve oxidative and nitrosative stress. Nitric oxide is also capable of directly interacting with mitochondria through inhibition of respiration or by permeability transition. Reaction of nitric oxide with metal ions include its direct interaction with the metals or with oxo complexes thereby reducing them to lower valent state. Excessive production of nitric oxide can be studied by inhibiting the synthetic pathway of nitric oxide using both selective or specific nitric oxide synthase inhibitor or non-selective nitric oxide synthase inhibitor with respect to isoforms of nitric oxide.  相似文献   
993.
Oral cancer has emerged as an alarming public health problem with increasing incidence and mortality rates all over the world. Therefore, the implementation of newer screening and early detection approaches are of utmost importance which could reduce the morbidity and mortality associated with this disease. Sensitive and specific biomarkers for oral cancer are likely to be most effective for screening, diagnosis, staging and follow-up for this dreaded malignancy. Unlike other deep cancers, oral cancer is located in oral cavity. Hence, the direct contact between saliva and oral cancer lesion makes the measurement of tumor markers in saliva an attractive alternative to serum and tissue testing. The DNA, RNA and protein molecules derived from the living cancer cells can be conveniently obtained from saliva. Thus, salivary biomarkers, a non-invasive alternative to serum and tissue-based biomarkers may be an effective modality for early diagnosis, prognostication and monitoring post therapy status. In the current post-genomic era, various technologies provide opportunities for high-throughput approaches to genomics and proteomics; which have been used to evaluate altered expressions of gene and protein targets in saliva of oral cancer patients. The emerging field of salivary biomarkers has great potentials to prove its clinical significance to combat oral cancer. Hence, we have reviewed importance of several salivary genomics and proteomics biomarkers for oral cancer.  相似文献   
994.
Perhaps nothing strikes more fear into the hearts of all tenure-track professors than the process itself. Are four papers in this journal good enough? Are eight papers in another okay? What if someone doesn’t like me or my area of research? These issues have plagued academia since the first essay was penned by the first researcher hundreds of years ago. While personal bias and journal preference continue to infect honest tenure reviews, solutions exist. This does not mean we have a magic bullet to solve issues of bullying or elitism. However, if we are honest in our desire to improve the Academy, we should avail ourselves of every possible tool for improvement. This essay is based on a survey sent to 2,500 mass communication educators. Of the almost 500 respondents, roughly 10% took the time to express emotions that ranged from fear and confusion to outright rage and anger, all because what ought to be clear is not. The author offers 10 ideas of how academia can improve its evaluation of new faculty, as well as a few suggestions regarding the unnecessary inclusion of personal issues in a process that ought to be about creating better researchers and teachers.  相似文献   
995.
996.
The article documents the editorial relationship between Peter Carey and his New York based editor for Knopf, Gary Fisketjon, who worked with Carey on his True History of the Kelly Gang. This account provides the basis for a discussion of how globalised publishing, while promising unity—a single text across all territories—has instead introduced a tension into the previously cohesive triad of author, editor, and the single authorized text. As Fisketjon’s experience lays bare, major contemporary texts that are published in multiple editions in different global centers may well proceed through competing or at least parallel editing processes with different presses, different editors, and in different publishing territories. The authorized single edition, even of major literary texts, has been replaced by competing editions. The single edit and editor have been replaced by competing “servant[s] of the writer” (to use Fisketjon’s phrase). Cohesion, while not quite giving way to disunity, gives way to multiplicity and plurality. The experience of the Kelly Gang book is cast against a longer narrative of Carey’s interactions with editors including the University of Queensland Press (UQP) from the 1970s and Faber from the 1980s.  相似文献   
997.
The purpose of this article is to add to the collective body of knowledge on student behavior and attitudes relative to the adoption of digital textbooks. The article summarizes an ongoing research project that examines past, current and evolving behavior in the classroom related to digital textbooks and school. It includes students, faculty and administrative attitudes behaviors and perceptions. This research was undertaken at the Sawyer Business School of Suffolk University in Boston, Massachusetts. Student attitudes and behavior toward their use of digital textbooks (eTextbooks) in higher education was examined in an ongoing longitudinal study over two years at Sawyer Business School, Suffolk University. Students in the class were divided into six teams. Five of the teams were assigned an eTextbook device and the sixth team was given a paper textbook for use through the semester. The digital technologies examined were: Amazon Kindle, Sony eReader Touch, Apple iPad, enTourage eDGe, and CourseSmart. Student attitudes and behaviors were examined pre and post class by survey each semester, and during the semesters through quizzes, journals and classroom discussion. Differential learning was measured between the six teams. Student attitudes and behaviors are becoming more receptive to and accepting of using digital textbooks each year. There was no significant difference in learning between the eTextbook devices teams or between them and the paper textbook team.  相似文献   
998.
The migration from print books to ebooks is more than a change of format; it is also the first step in an ongoing process, whose final outcome is hard to predict. Ebooks are likely to lead to a restructuring of the industry by enabling cross-border commerce. This in turn is likely to lead to difficult disputes over territorial rights. It appears probable that these disputes will be resolved by an assertion of the dominance of the American market and the publishers that already serve it well, as authors are likely to place their rights with practitioners in the largest markets. This in turn will lead to the acquisition of many smaller “national” publishers, which cannot compete on a world stage with truly global publishers. But rather than simply becoming sources of editorial product for American-based global marketing machines, smaller publishers operating in different regions will respond through innovation, both in product design (attempting to do electronically what cannot be done in print) and in developing new marketing plans that the giant publishers would be indisposed to pursue.  相似文献   
999.
The forces for change in the 600 hundred-year history of book publishing have never been more powerful and fundamental than in 2011. Barely 12 months ago, what publishers viewed as “innovation” was the creation of digitized versions of physical books to be ‘consumed’ on e-reading devices. As 2011 begins, that change is largely regarded as accepted business practice, and the edge of “innovation” is moving in more complex directions. Publishing finds itself in the midst of a ‘phase shift’ from the scarcity model of print to a complex, new world of digital abundance. The dimensions of change, moreover, its speed, and its extent are still unknown. While book publishing begins with the creative work of authors, digital technologies are turning the business models inside out. Among the forces for change acting on book publishing, this article examines several phenomena that are working their way in from the edge to the center of the industry, including complex interwoven considerations around container, context, and customer.  相似文献   
1000.
The critical task of predicting clicks on search advertisements is typically addressed by learning from historical click data. When enough history is observed for a given query-ad pair, future clicks can be accurately modeled. However, based on the empirical distribution of queries, sufficient historical information is unavailable for many query-ad pairs. The sparsity of data for new and rare queries makes it difficult to accurately estimate clicks for a significant portion of typical search engine traffic. In this paper we provide analysis to motivate modeling approaches that can reduce the sparsity of the large space of user search queries. We then propose methods to improve click and relevance models for sponsored search by mining click behavior for partial user queries. We aggregate click history for individual query words, as well as for phrases extracted with a CRF model. The new models show significant improvement in clicks and revenue compared to state-of-the-art baselines trained on several months of query logs. Results are reported on live traffic of a commercial search engine, in addition to results from offline evaluation.  相似文献   
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