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91.
The methanol extract of the rhizome of Bergenia ciliata Sternb. (Saxifragaceae) has been evaluated for its potential in a cough model induced by sulphur dioxide gas in mice. The extract exhibited significant anti-tussive activity in a dose-dependent manner, as compared with control. The antitussive activity of the extract was comparable to that of codeine phosphate (10 mg/kg body wt.), a standard anti-tussive agent. The extract at doses of 100, 200 and 300 mg/kg body wt. (p.o.) showed significant inhibition of cough reflex by 28.7, 33.9 and 44.2%, respectively, within 90 min of the experiment. 相似文献
92.
Vinnakota Rajesh Ramakrishnan Anantha Maharasi Samdani A. Venugopal M. Anjali Ram B. Sri Krishnan S. Navaneetha Murugesan Dhandapani Sankaranarayanan Kavitha 《Protoplasma》2016,253(6):1593-1597
Protoplasma - Climate change drastically affects the cultivation of rice, and its production is affected significantly by water stress. Adaptation of a plant to water deficit conditions is... 相似文献
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95.
G. Annadurai R. Y. Sheeja S. Mathalai Balan T. Murugesan V. R. Srinivasamoorthy 《Bioprocess and biosystems engineering》1999,20(1):37-43
Equilibrium conditions in the adsorption of a basic dye on Chitosan were studied. The Factorial Design methods and Analysis of Variance have been applied in the experimental determination of adsorption equilibrium constants. Factorial design with three levels of temperature (30v°C, 45v°C, 60v°C), pH (6.7, 8.1, 9.5), particle size (0.177 mm, 0.914 mm, 1.651 mm) was used in identification of significant effects and interactions in the calculation of the equilibrium constants. The dye adsorption capacity of chitosan was found to increase by decreasing the particle size and increasing temperature and pH. The methodology identifies the principal experimental variables, which have the greatest effect on the adsorption process. 相似文献
96.
This study investigated the cytotoxicity, genotoxicity, and growth inhibition effects of four different inorganic nanoparticles (NPs) such as aluminum (nAl), iron (nFe), nickel (nNi), and zinc (nZn) on a dibenzofuran (DF) degrading bacterium Agrobacterium sp. PH-08. NP (0–1,000 mg L?1) -treated bacterial cells were assessed for cytotoxicity, genotoxicity, growth and biodegradation activities at biochemical and molecular levels. In an aqueous system, the bacterial cells treated with nAl, nZn and nNi at 500 mg L?1 showed significant reduction in cell viability (30–93.6 %, p < 0.05), while nFe had no significant inhibition on bacterial cell viability. In the presence of nAl, nZn and nNi, the cells exhibited elevated levels of reactive oxygen species (ROS), DNA damage and cell death. Furthermore, NP exposure showed significant (p < 0.05) impairment in DF and catechol biodegradation activities. The reduction in DF biodegradation was ranged about 71.7–91.6 % with single NPs treatments while reached up to 96.3 % with a mixture of NPs. Molecular and biochemical investigations also clearly revealed that NP exposure drastically affected the catechol-2,3-dioxygenase activities and its gene (c23o) expression. However, no significant inhibition was observed in nFe treatment. The bacterial extracellular polymeric materials and by-products from DF degradation can be assumed as key factors in diminishing the toxic effects of NPs, especially for nFe. This study clearly demonstrates the impact of single and mixed NPs on the microbial catabolism of xenobiotic-degrading bacteria at biochemical and molecular levels. This is the first study on estimating the impact of mixed NPs on microbial biodegradation. 相似文献
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98.
Hannah Gardener Della David Morte Mitchell SV Elkind Ralph L Sacco Tatjana Rundek 《BMC cardiovascular disorders》2009,9(1):1-8
Background
Heterogeneity in B-type natriuretic peptide (BNP) levels, especially among individuals with acute heart failure with normal left ventricular ejection fraction (HFNEF), can cause confusion in interpreting results. We investigated the characteristics of cases of acute HFNEF with only modestly elevated BNP.Methods
One hundred forty-two patients with acute or acute exacerbation of chronic HFNEF were divided into two groups by BNP level: BNP < 100 pg/ml (NB group, n = 45) and BNP ≥ 100 pg/ml (B group, n = 97). We compared clinical findings, echocardiography results, and neurohormonal factors between these two groups.Results
In the NB group, a history of open-heart surgery (OHS) was more frequent (71% vs. 22%, p < 0.0001) and hypertension was less frequent (p = 0.0005). Left atrial diameter (LAd) was higher (p = 0.0026), while interventricular septal thickness, posterior wall thickness, relative wall thickness, left ventricular mass index were lower (p = 0.0005, p = 0.0225, p = 0.0114, p = 0.0051, respectively) in the NB group. In patients with HFNEF, a history of OHS remained an independent predictor of BNP level (< 100 pg/ml) after adjustment for hypertension, age, LAd, and interventricular septal thickness (odds ratio 3.6, p = 0.0252).Conclusion
We found associations between acute HFNEF with less elevated BNP and a history of OHS. In a patient suspected of HFNEF, a history of OHS is considered diagnostic evidence of presence of diastolic heart failure when plasma levels of BNP are less elevated. 相似文献99.
Eun-Ju Kim Jong-Rok Jeon Young-Mo Kim Kumarasamy Murugesan Yoon-Seok Chang 《Applied microbiology and biotechnology》2010,87(4):1569-1577
The aerobic metabolism of monofluorophenols (mono-FPs) by the actinomycete, Pseudonocardia benzenivorans, was studied. This strain was able to grow on 4-fluorophenol (4-FP) and readily transform 2- and 3-fluorophenol to the corresponding
metabolites. The detailed mechanism of mono-FPs degradation by P. benzenivorans was elucidated from enzymatic assays and the identification of reaction intermediates by high-performance liquid chromatography
(HPLC) and gas chromatography–mass spectrometry. Two types of fluorocatechols (i.e., 3- and 4-fluorocatechol) were identified
as the key transformation products. During 4-FP degradation, only 4-fluorocatechol was detected, and a stoichiometric level
of fluoride was released. Both fluorocatechols were observed together in cultures containing 3-fluorophenol (3-FP), while
only 3-fluorocatechol was found to accumulate in 2-fluorophenol (2-FP)-containing cultures. Whole-cell extracts of P. benzenivorans expressed catechol 1,2-dioxygenase activity, indicating that the transformation of the three tested mono-FPs proceeded via
ortho-cleavage pathway. The results presented in this paper provide comprehensive information regarding the metabolism of mono-FPs
by a single bacterium. 相似文献
100.
Preparation of biopolymer fibers by electrospinning from room temperature ionic liquids 总被引:4,自引:0,他引:4
Viswanathan G Murugesan S Pushparaj V Nalamasu O Ajayan PM Linhardt RJ 《Biomacromolecules》2006,7(2):415-418
Electrospinning is a versatile process used to prepare micro- and nano- sized fibers from various polymers dissolved in volatile solvents. In this report, cellulose and cellulose-heparin composite fibers are prepared from nonvolatile room temperature ionic liquid (RTIL) solvents by electrospinning. RTILs are extracted from the biopolymer fiber after the fiber formation using a cosolvent. Micron to nanometer sized, branched fibers were obtained from 10% (w/w) concentration of polysaccharide biopolymer in RTIL solution with an applied voltage of 15-20 kV. Cellulose-heparin composite fibers showed anticoagulant activity, demonstrating that the bioactivity of heparin remained unaffected even on exposure to a high voltage involved in electrospinning. 相似文献