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1.
Shailesh Kumar Atma P. Dwivedi Vivek Kr. Kashyap A.K. Saxena A.K. Dwivedi Ranjana Srivastava Devi P. Sahu 《Bioorganic & medicinal chemistry letters》2013,23(8):2404-2407
Synthesis of a library of novel trans 6-methoxy-1,1-dimethyl-2-phenyl-3-aryl-2,3-dihydro-1H-inden-4-yloxy alkyl amines and their antimycobacterial activity against drug sensitive and multidrug resistant strains of Mycobacterium tuberculosis have been reported. All the new compounds in the series exhibited MIC between 1.56 and 6.25 μg/ml. Two compounds 1i and 1j with low MIC and low cytotoxicity showed significant reduction in CFU in infected mouse macrophages at 1× MIC concentration. The compound 1i inhibited the growth of M. tuberculosis in mice at 100 mg/kg dose with 1.35 log10 reduction of CFU in lungs tissue and was active against non-replicating Mycobacterium tuberculosis under anaerobic condition. 相似文献
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A microcomputer mainframe linked system is described which allows video camera data capture and storage of one-dimensional whole-cell protein electrophoresis gel images, processing of normalized traces to produce a similarity matrix, and analysis of the matrix using the commercial cluster analysis program CLUSTAN. A new similarity coefficient is introduced which takes into account both band position and intensity. Forty-five strains of Haemophilus influenzae, including the eight biotypes and six serotypes, were analyzed using this system. Results demonstrated groupings which are consistent with known genetic relationships. 相似文献
3.
Atrial natriuretic factor alters autonomic interactions in the control of heart rate in conscious rats 总被引:2,自引:0,他引:2
U Ackermann J Khanna T G Irizawa 《Canadian journal of physiology and pharmacology》1988,66(7):930-936
Regulation of heart rate was studied in rats receiving either i.v. saline at 64 microL/min or synthetic 28-residue rat atrial natriuretic peptide (ANF) at a dose sufficient to decrease mean arterial blood pressure by 10%. Autonomic influences were deduced from steady-state heart rate responses of each group to propranolol, atropine, or propranolol and atropine combined. A multiplicative model of heart rate control was used to derive quantitatively from the data the modulation of intrinsic heart rate by sympathetic and parasympathetic mechanisms. Animals receiving ANF showed a lower heart rate than control animals. This relative bradycardia was abolished by atropine. Blocking of sympathetic effects with propranolol had no effect on basal heart rate in either group, and atropinization led to significant increases in heart rate in both groups of rats. Mathematical analysis of the results showed that the bradycardia produced by ANF was due predominantly to a reduced intrinsic heart rate and to enhanced vagal inhibition of postganglionic sympathetic activity. Parasympathetic contribution to heart rate in the absence of sympathetic activity was negligible in control rats and small during ANF. We conclude that the major influences of ANF on heart rate control are a decrease of intrinsic heart rate and enhanced parasympathetic inhibition of postganglionic presynaptic sympathetic activity. 相似文献
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Kainate receptors (KARs) are a class of ionotropic glutamate receptors that are expressed throughout the central nervous system. The function and subcellular localization of KARs are tightly regulated by accessory proteins. We have previously identified the single-pass transmembrane proteins, Neto1 and Neto2, to be associated with native KARs. In the hippocampus, Neto1, but not Neto2, controls the abundance and modulates the kinetics of postsynaptic KARs. Here we evaluated whether Neto2 regulates synaptic KAR levels in the cerebellum where Neto1 expression is limited to the deep cerebellar nuclei. In the cerebellum, where Neto2 is present abundantly, we found a ∼40% decrease in GluK2-KARs at the postsynaptic density (PSD) of Neto2-null mice. No change, however, was observed in total level of GluK2-KARs, thereby suggesting a critical role of Neto2 on the synaptic localization of cerebellar KARs. The presence of a putative class II PDZ binding motif on Neto2 led us to also investigate whether it interacts with PDZ domain-containing proteins previously implicated in regulating synaptic abundance of KARs. We identified a PDZ-dependent interaction between Neto2 and the scaffolding protein GRIP. Furthermore, coexpression of Neto2 significantly increased the amount of GRIP associated with GluK2, suggesting that Neto2 may promote and/or stabilize GluK2:GRIP interactions. Our results demonstrate that Neto2, like Neto1, is an important auxiliary protein for modulating the synaptic levels of KARs. Moreover, we propose that the interactions of Neto1/2 with various scaffolding proteins is a critical mechanism by which KARs are stabilized at diverse synapses. 相似文献
6.
Eriocaulon raipurense (Eriocaulaceae) is described and illustrated as a new species from Madhya Pradesh, India. The species is closely allied to E. hamiltonianum but differs in the size and apex of involucral bancts, white-pilose nature of floral bracts and colour of female petals. 相似文献
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The concepts of feed pretreatment, phase separation, and whole-cell immobilization technology have been incorporated in this investigation for the development of rational and cost-effective two- and three-stage methane recovery systems from water hyacinth (WH)Analyses of laboratory data reveal that a three-stage system could be designed with an alkali pretreatment stage [3.6% Na(2)CO(3) + 2.5% Ca(OH)(2) W/W, 24 h HRT] followed by an open acid reactor (2.1 days HRT) and closed immobilized methane reactor (12 h HRT), providing steady-state COD conversion of 62-65%, TVA conversion of 91-95%, and gas productivity of 4.08-5.36 L/L reactor volume/day with 82% methane. A gas yield of 50 L/kg WH/day (dry wt basis) at 35-37 degrees C is possible with this system. Insulation bricks, with particle size distribution of 500-3000 mum, were used as support material in the reactors at organic loading rate of 20 kg COD/m(3) day. The reactors matured in 15-18 weeksSubstantial reduction in retention time for the conversion of volatile acids in immobilized methane reactors prompted further research on the combined immobilized reactor to make possible an additional reduction in the cost of a WH-based biogas system. Evaluation of laboratory data reveals that a two-stage system could be designed with an open alkali pretreatment stage and a combined immobilized reactor (12 h HRT), providing steady-state COD conversion of 53% and gas productivity of 3.1 L/L reactor volume/day with 86% methane. A gas yield of 44 L/kg WH/day (dry wt basis) at 35-37 degrees C could be obtained from this system. Insulation bricks, with 500-1000 mum particle size distribution, was used as support material at an organic loading rate of 15 kg COD/m(3) day. Notwithstanding the fact that the technology in this study has been developed with water hyacinth as substrate, the implicit principles could be extended to any other organic substrate. 相似文献
9.
Blood samples from 16 female camels were collected at monthly intervals commencing from 60 d post. breeding until the last month of gestation. Two camels failed to conceive and two had unnoticed abortions. The average gestation period was 398+/-13 and 372+/-11 in camels bearing male and female fetus, respectively, with an overall mean of 383+/-9 d. Sera were analyzed for thyroxine (T(4)) and triiodothyronine (T(3)) by radioimmunoassay. Mean T(4) and T(3) concentrations varied from 76 to 116 ng/ml and 0.73 to 1.32 ng/ml, respectively, during various stages of gestation. In general, the T(4) and T(3) levels were higher during early pregnancy, with lowest values in the tenth month. T(4):T(3) ratio showed minor, nonsignificant fluctuations. Age of dam of sex of fetus had no effect on hormone levels. Similarly, hormone levels were not affected by failure of conception or by abortion. 相似文献
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