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31.
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
32.
Zi Yue’er 《中外文化交流(英文版)》2011,(11):4-7
Public cultural ser vice has gained increasing attention worldwide in recent years. It has become ever y government’s top priority to build a well-developed public cultural service system, provide diverse cultural products and promote cultural consumption by the public. In one-day disccusions of the Cultural Session, participants shared each other’s experience in public cultural service, in particular, concepts and practices of Xi’an City. Participants reached a consensus of increasing exchanges and cooperation in the sector of public culture in the future. 相似文献
33.
In this study, we develop a finite element model to examine the oblique soccer ball bounce. A careful simulation of the interaction between the ball membrane and air pressure in the ball makes the model more realistic than analytical models, and helps us to conduct an accurate study on the effect of different parameters on a bouncing ball. This finite element model includes a surface-based fluid cavity to model the mechanical response between the ball carcass and the internal air of the ball. An experimental set-up was devised to study the bounce of the ball in game-relevant impact conditions. Ball speed, angle, and spin were measured before and after the bounce, as well as ball deformation and the forces during the impact. The finite element model has been validated with three different sets of data, and the results demonstrate that the finite element model reported here is a valuable tool for the study of ball bounce. After validation of the model, the effect of the friction coefficient on soccer ball bounce was studied numerically. Simulation results show that increasing the friction coefficient may result in reversal of the horizontal impact force. 相似文献
34.
Muhammad Rafiq Syeda Hina Batool Amna Farzand Ali Midrar Ullah 《The Journal of Academic Librarianship》2021,47(1):102280
The purpose of this study was to explore the university libraries' response during the COVID-19 pandemic and determine their working practices, services patterns, strategies applied, and role played. This study is a qualitative exploration by collecting data through in-depth interviews of purposely selected Heads of seven university libraries. The interview recordings were transcribed, translated, and analyzed thematically. The majority of the university libraries were physically closed for patrons in this pandemic but engaged with the users. Libraries revamped their web pages, reassigned resources, and planned robust online offerings. The university portal and other social media tools were less used communication tools during the pandemic. Library staff worked from home and there was a sense of over burden because of 24/7 connectivity and without any formal working policy addressing the new working routines. University librarians felt that digital divide, lack of digital literacy skills, and slow internet speed were the major barriers in their transition from physical to online mode and less use of library's online resources and web portals. Libraries see their individual and collective roles of societal and educational dimensions during these uncertain times. The study also made recommendations for the betterment of libraries' role in such situations. 相似文献
35.
[目的/意义] 针对"和+共享图书馆"的建设现状进行分析,反映长沙市民间自办公共阅读空间的一般性问题,为长沙市民间自办公共阅读空间可持续发展提出优化建议。[方法/过程] 通过现场观察、问卷调查、访谈法等方法对"和+共享图书馆"建设现状和特点进行剖析,认为存在专业人员短缺、空间利用率偏低、营销形式单一等问题。[结果/结论] 提出优化建议包括:构建运营管理机制;加强专业人员培养;增强公共阅读空间服务的可及性和丰富服务营销形式等,以促进长沙市民办公共阅读空间的良性发展。 相似文献
36.
Mohammed M. Hasanen Ali A. Al-Kandari Hussain Al-Sharoufi 《Globalisation, Societies & Education》2014,12(4):542-563
This study examines the influence of English language usage and international media on the strength of either national or global identity. The regression analysis of 354 responses reveals that individuals who studied at universities that use English as a medium of instruction show significant differences in the extent to which they embrace a global identity. Viewing local (Kuwaiti) television programmes and the use of the Internet predict national identity. This study discusses the social entities that are important factors in mitigating the influence of globalisation on national identity. It concludes that the argument that globalisation and Westernisation are two faces of the same coin is overstated. 相似文献
37.
Fatemeh Lashkari Ebrahim Bagheri Ali A. Ghorbani 《Information processing & management》2019,56(3):733-755
Traditional information retrieval techniques that primarily rely on keyword-based linking of the query and document spaces face challenges such as the vocabulary mismatch problem where relevant documents to a given query might not be retrieved simply due to the use of different terminology for describing the same concepts. As such, semantic search techniques aim to address such limitations of keyword-based retrieval models by incorporating semantic information from standard knowledge bases such as Freebase and DBpedia. The literature has already shown that while the sole consideration of semantic information might not lead to improved retrieval performance over keyword-based search, their consideration enables the retrieval of a set of relevant documents that cannot be retrieved by keyword-based methods. As such, building indices that store and provide access to semantic information during the retrieval process is important. While the process for building and querying keyword-based indices is quite well understood, the incorporation of semantic information within search indices is still an open challenge. Existing work have proposed to build one unified index encompassing both textual and semantic information or to build separate yet integrated indices for each information type but they face limitations such as increased query process time. In this paper, we propose to use neural embeddings-based representations of term, semantic entity, semantic type and documents within the same embedding space to facilitate the development of a unified search index that would consist of these four information types. We perform experiments on standard and widely used document collections including Clueweb09-B and Robust04 to evaluate our proposed indexing strategy from both effectiveness and efficiency perspectives. Based on our experiments, we find that when neural embeddings are used to build inverted indices; hence relaxing the requirement to explicitly observe the posting list key in the indexed document: (a) retrieval efficiency will increase compared to a standard inverted index, hence reduces the index size and query processing time, and (b) while retrieval efficiency, which is the main objective of an efficient indexing mechanism improves using our proposed method, retrieval effectiveness also retains competitive performance compared to the baseline in terms of retrieving a reasonable number of relevant documents from the indexed corpus. 相似文献
38.
Sridhar Mishra Devanshi B. Dubey Krachi Agarwal Deval B. Dubey Shweta Verma Nida Shabbir Rashmi Kushwaha D Himanshu Reddy Uma Shankar Singh Wahid Ali 《Indian journal of clinical biochemistry : IJCB》2023,38(2):172
Lymphocyte dysregulation in coronavirus disease-19 (COVID-19) is a major contributing factor linked to disease severity and mortality. Apoptosis results in the accumulation of cell-free DNA (cfDNA) in circulation. COVID-19 has a heterogeneous clinical course. The role of cfDNA levels was studied to assess the severity and outcome of COVID-19 patients and correlated with other laboratory parameters. The current case series included 100 patients with mild COVID-19 (MCOV-19) and 106 patients with severe COVID-19 (SCOV-19). Plasma cfDNA levels were quantified using SYBR green quantitative real-time PCR through amplification of the β-actin gene. CfDNA level was significantly higher in SCOV-19 at 706.7 ng/ml (522.6–1258) as compared to MCOV-19 at 219.8 ng/ml (167.7–299.6). The cfDNA levels were significantly higher in non-survivor than in survivors (p = 0.0001). CfDNA showed a significant correlation with NLR, ferritin, LDH, procalcitonin, and IL-6. The diagnostic sensitivity and specificity of cfDNA in the discrimination of SCOV-19 from MCOV-19 were 90.57% & 80%, respectively. CfDNA showed a sensitivity of 94.74% in the differentiation of non-survivors from survivors. CfDNA levels showed a significant positive correlation with other laboratory and inflammatory markers of COVID-19. CfDNA levels, NLR, and other parameters may be used to stratify and monitor COVID-19 patients and predict mortality. CfDNA may be used to predict COVID-19 severity with higher diagnostic sensitivity. 相似文献
39.
The aim of this study was to examine the possibility of obtaining information about the heart rate and physiological load imposed on soccer players during a game. The study was conducted on 27 soccer players, 9 each from semi-professional, university and recreational soccer teams. Players from all positions (attack, midfield and defence) were selected for the study. Each subject's heart rate was monitored during a match using a short-range radio telemetry (Sport Tester PE3000), and was sampled at 5-s intervals. The results indicate that it is possible to monitor successfully the heart rate of players with such equipment. The mean heart rate and standard deviation for each player during match play were: semi-professional players (172 +/- 12, 176 +/- 9 and 166 +/- 15 for forwards, midfielders and defenders, respectively); university players (171 +/- 13, 173 +/- 10 and 156 +/- 13 for forwards, midfielders and defenders, respectively); and recreational players (173 +/- 13, 170 +/- 12 and 162 +/- 13 for forwards, midfielders and defenders, respectively). Analysis by playing position revealed that midfield and forward players has a greater mean heart rate during a game than defensive players. To examine the suitability and accuracy of the two methods of obtaining objective data on heart rate, comparisons were made between the Sport Tester PE3000 and a standard electrocardiograph (ECG) telemetry technique. The results show that both techniques produce similar results; the former was the more convenient.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
40.