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M S Jawahar S Sivasubramanian V K Vijayan C V Ramakrishnan C N Paramasivan V Selvakumar S Paul S P Tripathy R Prabhakar 《BMJ (Clinical research ed.)》1990,301(6748):359-362
OBJECTIVE--To assess the efficacy of a short course chemotherapy regimen for treating tuberculosis of the lymph nodes in children. DESIGN--Open, collaborative, outpatient clinical trial. SETTING--Outpatient department of the Tuberculosis Research Centre, paediatric surgery departments of the Institute of Child Health and Hospital for Children and the Government Stanley Hospital, Madras, South India. PATIENTS--Children aged 1-12 years with extensive, multiple site, superficial tuberculous lymphadenitis confirmed by biopsy (histopathology or culture). INTERVENTIONS--Patients were treated with a fully supervised intermittent chemotherapy regimen consisting of streptomycin, rifampicin, isoniazid, and pyrazinamide three times a week for two months followed by streptomycin and isoniazid twice a week for four months on an outpatient basis. Surgery was limited to biopsy of nodes for diagnosis and assessment. MAIN OUTCOME MEASURES--Response to chemotherapy was assessed by regression of lymph nodes and healing of sinuses and abscesses during treatment and follow up. Compliance with treatment and frequency of adverse reactions were also estimated. RESULTS--197 Patients were admitted to the study and 168 into the analysis. The regimen was well tolerated and compliance was good with 101 (60%) patients receiving the prescribed chemotherapy within 15 days of the stipulated period of six months. Those whose chemotherapy extended beyond that period received the same total number of doses. Clinical response was favourable in most patients at the end of treatment. Sinuses and abscesses healed rapidly. Residual lymphadenopathy (exceeding 10 mm diameter) was present in 50 (30%) patients at the end of treatment; these nodes were biopsied. Fresh nodes, increase in size of nodes, and sinuses and abscesses occurred both during treatment and follow up. After 36 months of follow up after treatment only 5 (3%) patients required retreatment for tuberculosis. CONCLUSION--Tuberculous lymphadenitis in children can be successfully treated with a short course chemotherapy regimen of six months. 相似文献
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Acylation of carcinogenic hydroxamic acids by carbamoyl phosphate to form reactive esters 总被引:3,自引:0,他引:3 下载免费PDF全文
Two methylated derivatives of arginine were isolated from the encephalitogenic protein of myelin from the central nervous system. Evidence is presented for the proposed structures, omega-NN'-dimethylarginine and omega-N-monomethylarginine. In the encephalitogenic protein from human brain the proportion 1:6:10 for arginine:monomethylarginine:dimethylarginine residues was found to occur at position 107. Possible roles for the methylated arginine in conformational changes and altered ion-exchange behaviour are discussed. 相似文献
5.
J Mitra N R Prabhakar J L Overholt N S Cherniack 《Journal of applied physiology》1989,67(5):1814-1819
We studied the central effects of N-methyl-D-aspartate (NMDA) on respiration in 18 artificially ventilated cats anesthetized with alpha-chloralose. Unilateral topical application of NMDA (1 x 10(-8) mol) to the intermediate region of the ventrolateral medulla exaggerates the phrenic response to CO2 at end-tidal PCO2 levels of less than 50.0 Torr. At higher end-tidal PCO2 levels, however, such differences disappear. Unilateral NMDA application increases the activity of the right and left phrenic nerves equally. Furthermore, the magnitude of the phrenic response after unilateral application of NMDA was not different from that after bilateral application. NMDA also had a vasopressor action when applied to the ventrolateral medullary surface. In contrast to respiratory responses, bilateral application of NMDA caused a significant increase in blood pressure compared with unilateral application of NMDA. Application of the NMDA antagonist 2-amino-5-phosphonovaleric acid abolished both the blood pressure and respiratory effects of NMDA. These results suggest that CO2 and NMDA may act on a common respiratory premotoneuron to produce stimulation of breathing. Because blood pressure responses, unlike respiratory responses, were greater after bilateral application than after unilateral application of NMDA, it is suggested that the neural substrates for the two effects of NMDA seem to be different. 相似文献
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Media optimization studies are carried out with the objective of maximising glucose isomerase production by Arthrobacter sp. The recommended media consists of 1.0% (w/v) xylose, 1.0% peptone, 0.5% yeast extract, 0.025% MgSO4·7H2O, 0.6% (NH4)2HPO4 and 0.2% KH2PO4. Activity of the enzyme produced in this media is 11.2 units/ml. Growth cycle for batch cultivation is studied and the lag period is 2 hours, followed by exponential phase extending upto 32 hours. 相似文献
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Lectin recognition of host-like saccharide motifs in streptococcal cell wall polysaccharides 总被引:10,自引:0,他引:10
Cisar John O.; Sandberg Ann L.; Abeygunawardana Chitrananda; Reddy G.Prabhakar; Bush C.Allen 《Glycobiology》1995,5(7):655-662
Viridans streptococci that participate in the microbial colonizationof teeth have cell wall polysaccharides composed of linear phosphodiester-linkedhexa- or heptasaccharide repeating units, each containing ahost-like disaccharide motif, either Galß1 相似文献
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Photosynthetic carboxylating enzymes and the effects of light and temperature on 14CO2 efflux in two species of gymnosperm leaves were studied. The activity of RuBP carboxylase was high and that of PEP carboxylase was very low when compared to C4 plants. The CO2 compensation point was high. 14CO2 efflux was greater in light than in darkness and the ratio (L/D) increased with increase in temperature and light intensity. The inhibitors of glycolate metabolism showed decreased 14CO2 evolution in light while dark respiration was unaffected. It is concluded that both Cycas circinalis, L. and Cycas beddomei Dyer are C3 plants. 相似文献
9.
Hegde Namita Juvale Kapil Prabhakar Bala 《International journal of peptide research and therapeutics》2020,26(4):2129-2135
International Journal of Peptide Research and Therapeutics - Protection and subsequent deprotection of amino acid functional groups play a key role in regioselective peptide synthesis. For... 相似文献
10.
Mohammad-Reza Ghovanloo Koushik Choudhury Tagore S. Bandaru Mohamed A. Fouda Kaveh Rayani Radda Rusinova Tejas Phaterpekar Karen Nelkenbrecher Abeline R. Watkins Damon Poburko Jenifer Thewalt Olaf S. Andersen Lucie Delemotte Samuel J. Goodchild Peter C. Ruben 《The Journal of general physiology》2021,153(5)
Cannabidiol (CBD) is the primary nonpsychotropic phytocannabinoid found in Cannabis sativa, which has been proposed to be therapeutic against many conditions, including muscle spasms. Among its putative targets are voltage-gated sodium channels (Navs), which have been implicated in many conditions. We investigated the effects of CBD on Nav1.4, the skeletal muscle Nav subtype. We explored direct effects, involving physical block of the Nav pore, as well as indirect effects, involving modulation of membrane elasticity that contributes to Nav inhibition. MD simulations revealed CBD’s localization inside the membrane and effects on bilayer properties. Nuclear magnetic resonance (NMR) confirmed these results, showing CBD localizing below membrane headgroups. To determine the functional implications of these findings, we used a gramicidin-based fluorescence assay to show that CBD alters membrane elasticity or thickness, which could alter Nav function through bilayer-mediated regulation. Site-directed mutagenesis in the vicinity of the Nav1.4 pore revealed that removing the local anesthetic binding site with F1586A reduces the block of INa by CBD. Altering the fenestrations in the bilayer-spanning domain with Nav1.4-WWWW blocked CBD access from the membrane into the Nav1.4 pore (as judged by MD). The stabilization of inactivation, however, persisted in WWWW, which we ascribe to CBD-induced changes in membrane elasticity. To investigate the potential therapeutic value of CBD against Nav1.4 channelopathies, we used a pathogenic Nav1.4 variant, P1158S, which causes myotonia and periodic paralysis. CBD reduces excitability in both wild-type and the P1158S variant. Our in vitro and in silico results suggest that CBD may have therapeutic value against Nav1.4 hyperexcitability. 相似文献