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21.
Narender Reddy Emmadi Krishnaiah Atmakur Ganesh Kumar Chityal Sujitha Pombala Jagadeesh Babu Nanubolu 《Bioorganic & medicinal chemistry letters》2012,22(23):7261-7264
A series of fluorinated tetrahydropyrano[3,2-c]chromenes and dihydropyrano[3,2-b]pyran derivatives have been synthesized and their in vitro cytotoxic activities have been determined in cervical cancer cell line (HeLa), human breast adenocarcinoma cell line (MDA-MB-231 and MCF-7) and human alveolar adenocarcinoma cell line (A549). Compounds 4g, 4k, 4p showed a very potent activity against MDA-MB-231, and 4c, 4p showed promising activity against MCF-7, while compounds 4c, 4g, 4p showed moderate activity against HeLa. 相似文献
22.
23.
Jin CH Krishnaiah M Sreenu D Rao KS Subrahmanyam VB Park CY Son JY Sheen YY Kim DK 《Bioorganic & medicinal chemistry》2011,19(8):2633-2640
A series of 1-substituted-3(5)-(6-methylpyridin-2-yl)-4-(quinolin-6-yl)pyrazoles 14a-e, 15a-e, 17a-c, and 18a-d have been synthesized and evaluated for their ALK5 inhibitory activity in an enzyme assay and in a cell-based luciferase reporter assay. The 6-quinolinyl pyrazole analogue 14b inhibited ALK5 phosphorylation with IC(50) value of 0.022 μM and showed 84% inhibition at 0.1 μM in a luciferase reporter assay using HaCaT cells permanently transfected with p3TP-luc reporter construct. 相似文献
24.
DNA from the telomeres contains a stretch of simple tandemly repeated sequences in which clusters of G residues alternate with clusters of T/A sequences along one DNA strand. Model telomeric G-clusters form four-stranded structures in presence of Na(I), K(I) and NH(4)(I) ions. Electrophoretic and spectroscopic studies were made with the telomeric related sequences d(T6G16) or d(G4T2G4T2G4T2G4). It was noticed earlier that G-quadruplex may either be inter-molecular, or intra-molecular, or a mixture of both. CD spectral characteristics of various G-quadruplex DNA suggests that the CD maximum at 293 nm corresponds to that of an intra-molecular G-quadruplex structure or hairpin dimers. Fluorescence titration studies also show that acridine and the bis-acridine are interacting with G-quadruplex DNA and destabilize the K(I)-quadruplex structure more efficiently than the quadruplex formed by NH(4)(I) ion. Among the two drugs studied, acridine is more capable of breaking the G-quadruplex structure than bis-acridine. This result is further confirmed by the CD experiments. 相似文献
25.
The objective of the study was to develop guar gum matrix tablets for oral controlled release of water-soluble diltiazem hydrochloride.
Matrix tablets of diltiazem hydrochloride, using various viscosity grades of guar gum in 2 proportions, were prepared by wet
granulation method and subjected to in vitro drug release studies. Diltiazem hydrochloride matrix tablets containing either
30% wt/wt lowviscosity (LM1), 40% wt/wt medium-viscosity (MM2), or 50% wt/wt high-viscosity (HM2) guar gum showed controlled
release. The drug release from all guar gum matrix tablets followed first-order kinetics via Fickian-diffusion. Further, the
results of in vitro drug release studies in simulated gastrointestinal and colonic fluids showed that HM2 tablets provided
controlled release comparable with marketed sustained release diltiazem hydrochloride tablets (D-SR tablets). Guar gum matrix
tablets HM2 showed no change in physical appearance, drug content, or in dissolution pattern after storage at 40°C/relative
humidity 75% for 6 months. When subjectd to in vivo pharmacokinetic evaluation in healthy volunteers, the HM2 tablets provided
a slow and prolonged drug release when compared with D-SR tablets. Based on the results of in vitro and in vivo studies it
was concluded that that guar gum matrix tablets provided oral controlled release of water-soluble diltiazem hydrochloride.
Published: June 30, 2005 相似文献
26.
Netheti V. S. Bhagavan R. Ravanamma Kummara Venkata Krishnaiah N. Ravi Upendra Kumar Kagola C. R. Kesavulu P. L. Saranya V. Venkatramu 《Luminescence》2023,38(10):1750-1757
Samarium (Sm3+)-doped glass has sparked a rising interest in demonstrating a noticeable emission in the range of 400–700, which is advantageous in solid-state lasers in the visible region, colour displays, undersea communication, and optical memory devices. This study reports the fabrication of Sm3+-doped bismuth–germanium–borate glasses were established using a standard melt-quenching technique and inspection by absorption, steady-state luminescence, and transient studies. The typical peaks of Sm3+ ions were detected in the visible range under 403 nm excitation. A strong emission band was detected at 599 nm that resembles the 4G5/2→6H7/2 transition of Sm3+ ions for BGBiNYSm0.5 glass. Furthermore, a reddish-orange (coral) luminescence at 646 nm that resembles the 4G5/2→6H9/2 transition was also perceived. The stimulated emission cross-section of 4G5/2 level for BGBiNYSm0.5 glass was 0.39 × 10−22 cm2. Lifetime of the 4G5/2 level was enhanced for the BGBiNYSm0.5 glass and decreased with an increase in active ion concentrations. The lifetime quenching of ions at the metastable state was because of energy transfer among Sm3+ ions by cross-relaxation channels. Commission Internationale de l'Éclairage (CIE) coordinates were evaluated from the emission spectra. Moreover, all the findings recommend these glass as light-emitting materials in the coral region at 599 nm for solid-state lighting applications. 相似文献
27.
Das B Reddy VS Krishnaiah M Sharma AV Ravi Kumar K Rao JV Sridhar V 《Phytochemistry》2007,68(15):2029-2034
Chemical examination of the flowers of Parthenium hysterophorus has resulted in the isolation of four acetylated pseudoguaianolides along with several known constituents. The structures of the compounds were derived from detailed studies of their spectral (1D and 2D NMR and FABMS) data and by comparison of the values with those of parthenin, a major known constituent of the plant. The cytotoxic activity of parthenin and the constituents was evaluated using Jurkat (human: T lymphocyte; acute T cell leukemia), HL-60 (human leukemia) and Hela (human cervical carcinoma) cells. 相似文献
28.
Rohit C. Khanna Gudlavalleti V. S. Murthy Pyda Giridhar Sannapaneni Krishnaiah Hira B. Pant Ghanshyam Palamaner Subash Shantha Subhabrata Chakrabarti Clare Gilbert Gullapalli N. Rao 《PloS one》2013,8(10)
Background
A large-scale prevalence survey of blindness and visual impairment (The Andhra Pradesh Eye Diseases Study [APEDS1]) was conducted between 1996-2000 on 10,293 individuals of all ages in three rural and one urban clusters in Andhra Pradesh, Southern India. More than a decade later (June 2009-March 2010), APEDS1 participants in rural clusters were traced (termed APEDS2) to determine ocular risk factors for mortality in this longitudinal cohort.Methods and Findings
Mortality hazard ratio (HR) analysis was performed for those aged >30 years at APEDS1, using Cox proportional hazard regression models to identify associations between ocular exposures and risk of mortality. Blindness and visual impairment (VI) were defined using Indian definitions. 799/4,188 (19.1%) participants had died and 308 (7.3%) had migrated. Mortality was higher in males than females (p<0.001). In multivariable analysis, after adjusting for age, gender, diabetes, hypertension, body mass index, smoking and education status the mortality HR was 1.9 (95% CI: 1.5-2.5) for blindness; 1.4 (95% CI: 1.2-1.7) for VI; 1.8 (95% CI: 1.4-2.3) for pure nuclear cataract, 1.5 (95% CI: 1.1-2.1) for pure cortical cataract; 1.96 (95% CI: 1.6-2.4) for mixed cataract, 2.0 (95% CI: 1.4-2.9) for history of cataract surgery, and 1.58 (95% CI: 1.3-1.9) for any cataract. When all these factors were included in the model, the HRs were attenuated, being 1.5 (95% CI: 1.1-2.0) for blindness and 1.2 (95% CI: 0.9-1.5) for VI. For lens type, the HRs were as follows: pure nuclear cataract, 1.6 (95% CI: 1.3-2.1); pure cortical cataract, 1.5 (95% CI: 1.1-2.1); mixed cataract, 1.8 (95% CI: 1.4-2.2), and history of previous cataract surgery, 1.8 (95% CI: 1.3-2.6).Conclusions
All types of cataract, history of cataract surgery and VI had an increased risk of mortality that further suggests that these could be potential markers of ageing. 相似文献29.
P. Padmini S. K. Rakshit K. Krishnaiah A. Baradarajan 《Bioprocess and biosystems engineering》1994,11(1):39-42
The authors have developed a continuous recycle reactor which efficiently performs emulsion type enzymatic reactions. The reactor column is filled with immobilised lipase and the reactions are effected by pumping the pre-prepared oil-water emulsion through the bottom of the reactor. A part of the product was recycled back and this type of recycling greatly improves the productivity of fatty acid compared to continuous once-through reactor without recycling. The recycle reactor could be continuously run for 35 days without decrease in conversions. The performance of the reactor was interpreted by a model and the theoretical conversion was compared with the experimental data.List of Symbols
F
AO
mol/min
feed rate
-
K
M g/l
Michaelis constant
-
R
recycle ratio
-
r
5
mol/(ml · min)
reaction rate
-
S
0 g/l
initial substrate concentration
-
V
max
mol/(ml · min)
maximum reaction velocity
-
V
R l
void volume of the reactor
-
x
s
fractional conversion
- Standard deviation
相似文献
30.
Sriram Padmanabhan M. Ramakrishna B.K. Lonsane M.M. Krishnaiah 《Letters in applied microbiology》1992,15(6):235-238
Leaching of alpha-amylase from bacterial bran, produced by Bacillus licheniformis M27 in solid state fermentation was about 2.2 times higher at 50°C as compared to that at 30°C. Further increase by about 19% in leaching efficiency was observed when contact time was extended from 60 to 120 min. The overall increase of 2.54 times under these strategies is of economic importance and no information was available earlier on enhanced leaching of enzyme from fermented bran at elevated temperatures. 相似文献