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1.
Ramesh Chander Farhan Rizvi A. K Khanna Ram Pratap 《Indian journal of clinical biochemistry : IJCB》2003,18(2):71-79
Guggulsterone, a mixture of cis (E) and trans (Z) isomers (7∶3 w/w) was synthesized from 16-DPA. The isomers were separated
by column chromatography and evaluated for cardioprotective and antioxidant activities. Myocardial necrosis induced by isoproterenol
in rats caused marked increase in serum creatine phosphokinase and glutamate pyruvate transaminase. Simultaneously in ischemic
heart, phospholipase, xanthine oxidase and lipid peroxides were enhanced following depletion of glycogen, phospholipids and
cholesterol. Treatment with guggulsterone and its both isomers at the dose of 50 mg/kg po., significantly protected cardiac
damage as assessed by the reversal of blood and heart biochemical parameters in ischemic rats. The cardioprotective activity
of guggulsterone and of both the isomers were compared with that of gemfibrozil at the same doses. Guggulsterone and both
the isomers at tested concentrations (5–20mM) inhibited oxidative degradation of lipids in human low-density lipoprotein and
rat liver microsomes induced by metal ionsin vitro. The drug counteracted against the generation of superoxide anions (O2) and hydroxyl radicals (OH−) in non-enzymic test systems. It is suggested that cardioprotective and antioxidant activities of synthetic guggulsterone
and guggulsterone obtained from gum resinCommiphora mukul that contains isomers E & Z in the ratio of 46∶54w/w are the same. 相似文献
2.
2011年,作为全球最大能源使用国以及二氧化碳排放国,中美的建筑业所消耗的能源分别占到全国能源总消耗量的25%和40%。在建筑节能领域,绿色建筑的出现为消除建筑业所带来的对能源以及环境的负面影响提供了解决方法。为了促进绿色建筑的市场转型,推进设计和施工的差异化,中美均制定了国家绿色建筑分等评级程序以及配套政策。1998年,美国绿色建筑协会首次推出能源与环境先导设计(LEED),而中国政府则于2008年建立了中国绿色建筑评价标识(GBEL)。本文对美国LEED与中国GBEL评级程序、流程、评分系统以及扶持政策作了对比分析,研究发现,虽然两国所采用的绿色建筑设计以及操作评级程序的评分等级较为相似,它们在项目管理、评分要求和分配以及扶持政策类型等方面存在差异。美国能源与环境先导设计是由建筑产业利益相关者委员会制定并实施管理的。判断是否达到认证水平的灵活性更高。中国绿色建筑评价标识则是由政府操控的。判断是否达到评级水平的要求更为严格。但是,中国政府将在2014年下半年对中国绿色建筑评价标识的评级程序作出修正。本文对评级程序以及扶植政策的相似点以及差异是如何影响绿色建筑技术以及市场的发展作了分析,还讨论了绿色建筑未来发展可能面临的挑战以及政策导向意义。 相似文献
3.
N. Khanna A. Garg K. K. Sharma R. Khosla 《Indian journal of clinical biochemistry : IJCB》1997,12(1):86-90
In the present study which was aimed to see the effect of zinc on pentylenetetrazole induced convulsive threshold in rats we found that zinc sulfate 100 μg intracerebroventricularly) and pentylenetetrazole (50 mg/kg intraperitoneally) produced dose related seizure activity; however, pretreatment with zinc decreased the threshold, increased the severity, incidence of multiple seizures and total duration of pentylenetetrazole induced seizures. Diazepam (5 mg/kg intraperitoneally) pretreatment increased the threshold and lowered the incidence of convulsions in zinc induced seizures which further confirms that the convulsive effect of zinc is through inhibition of gamma aimino butyric acid. 相似文献
4.
Tarun Khanna 《Research Policy》1995,24(6)
In a thirty-year period, firms in the high-end computer industry compete for technological leadership with select subgroups of firms. A clustering technique is used to identify these subgroups of firms. In each of the three such ‘races’ that I identify, a firm's racing rivals influence the evolution of its own technology frontier. This approach complements life-cycle and other models of technological evolution. A central role is assigned to strategic interactions between firms. Different kinds of strategic interactions lead to intra-race and inter-race behavior. I demonstrate how such inter-firm interactions map into technological evolution at the industry level and suggest that the patterns seen here can help us understand technological evolution in a range of environments. 相似文献
5.
6.
Ramesh Chander A. K. Khanna Kanwal Raj A. K. Rastogi 《Indian journal of clinical biochemistry : IJCB》2005,20(1):153-159
Indian black tea; CTC leaf and dust, produced by Tata Tea Limited, Kolkata, (India) was studiedin vitro as potential scavenger of oxygen free radicals. Super oxide anions were generated in a system containing xanthine—xanthine
oxidase (enzymic system) and by NADH- phenozine methosulphate (non enzymic system). Anions were assayed in terms of uric acid
formation and reduction of nitroblue tetrazolium salt, which were shown to be suppressed by tea extracts. Extracts from both
leaf and dust also inhibted the formation of hydroxyl radicalsin vitro in the enzymic system comprising hypoxanthine—Cu+2—sodium ascorbate and xanthine oxidase and in non enzymic system of deoxyribose—Cu+2—sodium ascorbate and H2O2 as well as the Cu+2 induced lipid peroxidation in human low density lipoprotein. Feeding with black tea in normal rats for sixty days increased
their antioxidant activity and their liver microsomes were shown to be protected against peroxidation of lipids as stimulated
by metal ions with enzymic or non enzymic reactants. Furthermore feeding with tea extracts in normal as well as triton WR—1339
induced hyperlipidemic rats caused decrease in their plasma levels of total cholesterol, phospholipids and triglycerides.
The antioxidant and lipid lowering activities of both extracts from CTC leaf and dust tea was comparable and may be due to
the presence of natural products like catechin and others. 相似文献
7.
Hemal P. Shroff Samindara Hardikar-Sawant Anuradha D. Prabhudesai 《International Journal of Disability, Development & Education》2017,64(5):514-525
Teachers play an important role in the diagnosis and management of Attention Deficit Hyperactivity Disorder (ADHD). There are no published studies on Indian teachers’ knowledge of ADHD. In the present study, the aim was to assess knowledge and misperceptions about ADHD among schoolteachers in Mumbai. A total of 106 teachers from 12 English-medium schools completed the Knowledge of Attention Deficit Disorders Scale and a demographic questionnaire. Overall, the teachers lacked adequate knowledge of ADHD, with only 49% of the responses being correct. Repeated measures ANOVA results indicated that the teachers’ scores on the three subscales of the measure were significantly different (F = 7.96, p < .01), with the score being highest on the symptoms subscale. In conclusion, teachers in Mumbai need training on general information and treatment of ADHD, with a focus on correcting common misperceptions that they have with regards to ADHD. 相似文献
8.
Anuradha Bharosay Vivek Vikram Bharosay Kiran Saxena Meena Varma 《Indian journal of clinical biochemistry : IJCB》2018,33(2):178-183
This study was undertaken to evaluate the role of serum neuron specific enolase (NSE) in prediction of disability and neurological worsening in hypertensive ischemic cerebrovascular stroke. 80 hypertensive ischemic stroke patients diagnosed by a neurologist as per WHO definition along with radiological findings suggestive of cerebrovascular stroke and differentiating from hemorrhagic stroke and 60 controls having essential hypertension coming to hospital because of regular checkup or headache but with no neurological disease were included in the study. Neurological disability was assessed by NIHSS at the time of admission (within 72 h from the onset of stroke) and on 7th day after admission and cases were categorized into mild, moderate and severe disability. Venous blood samples were drawn within 72 h from the onset of symptoms. The samples were processed as per the laboratory protocol. The serum NSE samples were analyzed using an enzyme immunoassay based on the sandwich technique. We observed raised serum NSE in hypertensive ischemic stroke (17.4 ± 5.4 ng/ml) with significant association between different hypertensive groups than in hypertensive controls (9.1 ± 0.75 ng/ml). Greater degree of disability was observed in hypertensive stroke patients with raised serum NSE and hypertensive patients with mean serum NSE level of 22.9 ± 3.6 ng/ml and dyslipidemia had greater probability of neurological worsening as compared to those with mean serum NSE level of 12.7 ± 1.2 ng/ml. Serum NSE levels can serve as a peripheral indicator of neuronal damage and assist in the prediction of disability and clinical outcome in hypertensive cerebrovascular ischemic stroke patients. 相似文献
9.
Vipin K. Agrawal Poonam Khanna Vijay K. Agrawal Larry W. Hughes 《Decision Sciences Journal of Innovative Education》2020,18(3):481-516
Ongoing curriculum change in higher education is essential to enhance student learning and better prepare them for the job‐market. However, research shows that faculty are reluctant to implement such changes because students generally react adversely thereby negating any potential benefits, and moreover, sanction faculty through lower evaluations and future enrollment. Yet, understanding of the effect of curriculum changes on students’ course and instructor perceptions is limited. In this article we attempt to fill this gap. Drawing on two empirical findings—students’ motivation to attend college becoming increasingly extrinsic since the 1960s and their inability to recognize, ex ante, the value‐added by a curriculum change—and the norm life‐cycle theory, we argue that any effort‐increasing or grade‐threatening change is viewed as non‐normative and will lead to an adverse student reaction. However, this adverse reaction will dissipate over time once a critical mass of students is convinced of the merits of the new curriculum. We find support for our hypotheses by analyzing change in student perceptions following curriculum changes at a U.S. University. In addition, we also find that once the adverse reaction dissipates, students’ perceptions of the new curriculum become more positive than the old curriculum, only to be reversed once the revised curriculum is accepted as the new norm. 相似文献
10.
Pamela W. Garner Nuria Gabitova Anuradha Gupta Thomas Wood 《Cultural Studies of Science Education》2018,13(4):889-903
We report on the development of an after-school and summer-based science, technology, engineering, and mathematics curriculum infused with the arts and social emotional learning content (STEAM SEL). Its design was motivated by theory and research that suggest that STEM education is well-suited for teaching empathy and other emotion-related skills. In this paper, we describe the activities associated with the development and design of the program and the curriculum. We provide expert-ratings of the STEAM and social emotional elements of the program and present instructor and participant feedback about the program’s content and its delivery. Our results revealed that infusing the arts and social emotional learning content into science education created a holistic STEM-related curriculum that holds potential for enhancing young children’s interest in and appreciation for science and its applications. The data also suggested that the program was well-developed and, generally well-executed. However, experts rated the STEAM elements of the program more positively than the SEL elements, especially with regard to sequencing of lessons and integration among the lessons and hands-on activities, indicating that program revisions are warranted. 相似文献