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931.
932.
933.
934.
A large number of pharmaceuticals exhibit polymorphism; 23% steroids, 60% sulfonamides, and 70% of barbiturates have shown
this property. In this study, we have investigated and compared a new technique termed as melt sonocrystallization (MSC) with
melt and sonocrystallization (SC) for induction of polymorphism in progesterone (PRG). Polymorphs were characterized by DSC,
XRD, FT-IR, and FT Raman spectroscopy. Melt sonocrystallized progesterone (MSC-PRG) contained both the polymorphs, more soluble
form II along with less soluble form I, whereas melt progesterone (M-PRG) and sonocrystallized progesterone (SC-PRG) contained
only form I. Improvement in dissolution characteristics of both the polymorphs were compared and form II was found to be more
readily soluble than form I in deionized water. Reduction in mean particle size of PRG during SC was also determined using
laser diffractometer. During stability testing (40°C/75% RH) for 1 month, metastable form II of MSC-PRG was found to be transformed
into its more stable state. MSC technique was thus found as a useful tool for induction of polymorphism. 相似文献
935.
Ravi Prakash Pal Veena Mani Deepika Tripathi Chander Datt 《Biological trace element research》2018,181(1):154-163
This study aims to investigate the contents of trace elements in the brain and serum of male chickens and the effect of selenium–chromium(VI) interaction. A chronic experimental model was established by supplementing 22.14 mg/kg K2Cr2O7 with 0.00, 0.31, 0.63, 1.25, 2.50, and 5.00 mg/kg Na2SeO3 mg/kg B.W. to water for chicken daily. After 14, 28, and 42 days of exposure to the solution, the brain and serum of chickens from each group were collected to detect the levels of Ca, Cu, Mn, Fe, Zn, and Mg by inductively coupled plasma mass spectrometer (ICP-MS). Cr(VI) time-dependently accumulated in the brain and serum. The contents of Cr increased both in the brain and serum with prolonged exposure. Cr contents in the brain and serum decreased in all Se groups compared with those in only Cr-treated groups. Ca contents decreased with prolonged exposure and increasing Se dosage. The contents of Cu and Mn increased on the 28th day but decreased on the 42nd day in the brain and serum. Fe and Zn contents decreased in the serum under prolonged exposure and increased on the 28th day but decreased on the 42nd day in the brain. Cr exposure did not significantly affect Mg contents in the brain but slightly decreased those in the serum. Therefore, appropriate doses of Se affected Cr accumulation, leading to adjustments in the contents and correlations of trace elements. 相似文献
936.
S Nityanand O N Tripathi N K Kapoor V A Rao P C Jain 《Indian journal of experimental biology》1972,10(5):368-370
937.
Summary Efect of sowing density on germination, establishment and growth of two perennial weeds,Eupatorium adenophorum spreng. andE. riparium Regel, was studied by sowing varying number of seeds of each species in pots. At high sowing density, seedling emergence did not proportionately increase with seed input. The yield and seed output per unit area was independent of sowing density. Survival of established plants was independent of soil moisture stress. The dry matter yield of both species declined at low moisture regime, the reduction being more inE. riparium. E. adenophorum produced more seeds at low moisture level, whileE. riparium at high moisture level. The resource allocation to roots was reduced due to moisture stress, especially inE. andenophorum. 相似文献
938.
Twenty-four male graduate volunteers were administered a battery of psychological tests--critical flicker fusion (CFF; alternate and simultaneous), reaction time (simple and choice), memory (forward and backward), and associative recall--to ascertain their performance capability during the different times of day. Each subject performed the tests on two occasions, once in the morning (10:00 h) and on the second occasion in the evening (15:00 h), on two successive days, following a statistically balanced design. Analysis of variance reflected superior performance on reaction time (choice) and memory (backward) in the evening and on associative recall in the morning. While no such effects were noticeable on CFF, appreciable changes in performance with the decreasing brightness level of its light sources was observed. Further work in this direction on a variety of cognitive tests and sensory functions under various times (more than two times) throughout the day is suggested. 相似文献
939.
J.R. Shubha P. Tripathi B.S. Somashekar N. Kurrey P. Bhatt 《Journal of applied microbiology》2021,131(6):2994-3007
940.
Surendra Singh Bisht Seerat Fatima Akhilesh K. Tamrakar Neha Rahuja Natasha Jaiswal Arvind K. Srivastava Rama P. Tripathi 《Bioorganic & medicinal chemistry letters》2009,19(10):2699-2703
A simple synthesis of phenyl butenoyl C-glycosides has been achieved by Aldol condensation of peracetylated glycosyl acetones with aromatic aldehydes followed by deacetylation with methanolic NaOMe. The selected butenoyl C-glycosides on conjugate addition of diethyl malonate resulted in polyfunctional alkanonyl glycosides in good yields. The butenoyl C- and alkanoyl C-glycosides were evaluated for their α-glucosidase, glucose-6-phosphatse and glycogen phosphorylase enzyme inhibitory activities in vitro. Three of the synthesized (3, 5 and 9) showed potent enzyme inhibitory activities as compared to standard drugs. Compounds 3, 5 and 9 were evaluated in vivo too displaying significant activity as compared to standard drugs acarbose and metformin. 相似文献