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101.
Using sonography to reveal and aspirate joint effusions 总被引:3,自引:0,他引:3
Fessell DP Jacobson JA Craig J Habra G Prasad A Radliff A van Holsbeeck MT 《AJR. American journal of roentgenology》2000,174(5):1353-1362
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103.
Magang Shou Wei Lu Prasad H Kari Cathie Xiang Yuexia Liang Ping Lu Dan Cui W Bart Emary Kimberly B Michel Jennifer K Adelsberger Janice E Brunner A David Rodrigues 《European journal of pharmaceutical sciences》2005,26(2):151-161
Enterohepatic recirculation (EHR) occurs via biliary excretion and intestinal reabsorption of a drug. Drug recycling through EHR can lead to a change in pharmacokinetic (PK) properties, such as reduced clearance (CL), extended half-life (T(1/2)) and increased plasma exposure (AUC). As a result, EHR may prolong the pharmacological effect of drugs. In the present study, the compound (Cpd A) was found to exhibit EHR in Rhesus monkeys associated with a reduction in CL (from 3.8 to 0.33 Lh(-1), IV; from 2.3 to 0.4 Lh(-1), PO), and an increase in T(1/2) (from 0.9 to 18 h, IV) and in AUC (from 1.5 to 17.4 microg h/mL, IV; from 2.8 to 16.3 microg h/mL, PO), by comparing the PK in the monkeys via the interruption of EHR (bile-duct cannulation) with that in the intact monkeys. A population four-compartment model was constructed based on recirculation loops incorporating all possible inputs (bile secretion, a lag-time model for gall bladder emptying, routes and amounts of a single dose administration) to fully evaluate the EHR of Cpd A. The plasma concentrations versus time profiles predicted from the model had a good fit to the values observed in the subjects and were further simulated with 90% confidence interval to demonstrate its utility. Thus, the model could be applied as a useful tool to evaluate the drugs or compounds that undergo EHR in different species. 相似文献
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Ravikanth Bhamidipati P Venkatesh Prajakta V Dravid Prasad C Narasimhulu Sastry Tvrs Jagattaran Das Ramesh Mullangi Nuggehally R Srinivas 《European journal of drug metabolism and pharmacokinetics》2005,30(3):187-193
The aim of this study was to determine the bioavailability of a novel oxazolidinone, DRF-6196, in mice and rats following intravenous (i.v) and oral dosing and to compare the pharmacokinetics with those obtained following linezolid dosing. Blood samples were drawn at predetermined intervals up to 24 h post-dose after either DRF-6196 or linezolid administration. The concentrations of DRF-6196 and linezolid in various plasma samples were determined by a HPLC method. Following oral administration maximum concentrations of DRF-6196 were achieved within 0.5 h irrespective of the species. While the doses increased in the ratio of 1 : 3 : 10, mean Cmax and AUC(0-infinity) values in mice for DRF-6196 increased in the ratio of 1 : 3.87 : 8.53 and 1 : 2.51 : 9.24, respectively. Both the Cmax and AUC(0-infinity) values increased almost proportional to the dose administered in mice. Following i.v administration, the concentration of DRF-6196 declined in a bi-exponential fashion with terminal elimination half-life of 1.5 h irrespective of the species. The systemic clearance and volume of distribution of DRF-6196 in mice were 1.14 L/h/kg and 0.66 L/kg, respectively after i.v administration, while the respective values in rats were 0.61 L/h/kg and 0.41L/kg, respectively. Elimination half-life ranged between 0.8-1.5 h. Absolute oral bioavailability of DRF-6196 was found to be 80-96% across the test dose range. Although plasma levels of DRF-6196 were lesser compared to linezolid in the initial hours, it may not have any consequences on the clinical effectiveness of the molecule. 相似文献
106.
107.
G Patil MI Khan DK Patel S Sultana R Prasad I Ahmad 《Environmental toxicology and pharmacology》2012,34(2):436-445
Dolomite is a natural mineral of great industrial importance and used worldwide, thus millions of workers are at risk of occupational exposure. Its toxicity is however, meagerly documented. In the present investigation, a dolomite powder obtained from its milling unit was analyzed by some standard methods namely, optical microscopy, transmission electron microscopy and dynamic light scattering. Results showed that dolomite powder contained particles of different shapes and size both microparticles (MPs) and nanoparticles (NPs), suggesting potential occupational exposure of these particles. An attempt was therefore, made to investigate dolomite toxicity in a particle size-dependent manner in human lung epithelial cells A(549). The comparative toxicity evaluation of MPs and NPs was carried out by assessing their effects on cell viability, membrane damage, glutathione, reactive oxygen species (ROS), lipid peroxidation (LPO), micronucleus (MN) and proinflammatory cytokines, namely tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6). These markers of cytotoxicity, genotoxicity and inflammation were assayed in cells exposed to MPs and NPs in a dose-and time-dependent manner. Invariably, their toxic effects were dose-and time-dependent while NPs in general were significantly more toxic. Notably, NPs caused oxidative stress, genotoxicity and inflammatory responses, as seen by significant induction of ROS, LPO, MN, TNF-α, IL-1β and IL-6. Thus, the study tends to suggest that separate health safety standards would be required for micrometer and nanometer scale particles of dolomite. 相似文献
108.
Maria L. Napier Dash Durga Clive J. Wolsley Sarah Chamney Sharon Alexander Rosie Brennan 《Ophthalmic genetics》2015,36(3):239-243
Background: To determine the role of rhodopsin (RHO) gene mutations in patients with sector retinitis pigmentosa (RP) from Northern Ireland.Design: A case series of sector RP in a tertiary ocular genetics clinic.Participants: Four patients with sector RP were recruited from the Royal Victoria Hospital (Belfast, Northern Ireland) and Altnagelvin Hospital (Londonderry, Northern Ireland) following informed consent.Methods: The diagnosis of sector RP was based on clinical examination, International Society for Clinical Electrophysiology of Vision (ISCEV) standard electrophysiology, and visual field analysis. DNA was extracted from peripheral blood leucocytes and the coding regions and adjacent flanking intronic sequences of the RHO gene were polymerase chain reaction (PCR) amplified and cycle sequenced.Main Outcome Measure: Rhodopsin mutational status.Results: A heterozygous missense mutation in RHO (c.173C?>?T) resulting in a non-conservative substitution of threonine to methionine (p. Thr58Met) was identified in one patient and was absent from 360 control individuals. This non-conservative substitution (p.Thr58Met) replaces a highly evolutionary conserved polar hydrophilic threonine residue with a non-polar hydrophobic methionine residue at position 58 near the cytoplasmic border of helix A of RHO.Conclusions: The study identified a RHO gene mutation (p.Thr58Met) not previously reported in RP in a patient with sector RP. These findings outline the phenotypic variability associated with RHO mutations. It has been proposed that the regional effects of RHO mutations are likely to result from interplay between mutant alleles and other genetic, epigenetic and environmental factors. 相似文献
109.
Ambak Kumar Rai Chandreshwar Prasad Thakur Prabin Kumar Sheetal Saini Amit Kumar Kureel Smita Kumari 《Immunological investigations》2018,47(2):125-134
Background: Natural Killer (NK) cell plays an important role in the innate immune system and is known to produce IFN-γ at an early stage of infection that is essential to eliminate intracellular infection like Leishmania spp. It is already established that Leishmania parasite inhibits the activity of NK cells, avoiding the encounter with the early innate immune response. This, in turn, favors establishment and further dissemination of the infection. Methods: In the present study, we have tried to measure the frequency of different phenotypic subsets of NK cells among visceral leishmaniasis (VL) patients. Results: We have phenotyped three distinct three distinct subsets (CD56–CD161+, CD56+CD161–, and CD56+CD161+) of NK (CD3–) cell using their specific markers CD161 and CD56. Conclusion: Interestingly, we observed selective loss of CD56+CD161+ subset of circulating NK (CD3–) cells. Importantly, the other subsets (i.e., CD56?CD161+ and CD56+CD161–) of circulating NK cells remain unaffected as compared with healthy subjects. 相似文献
110.
Yadvinder Singh M.D. Bhupinder Singh M.D. Shivakumar Bhairappa D.M. Khamitkar Shankar Rao Subramani D.M. Naviluru M. Prasad D.M. Manjunath C. Nanjappa D.M. 《Echocardiography (Mount Kisco, N.Y.)》2013,30(6):E171-E174
A previously healthy 16‐year‐old girl presented with history of fever of 3 months duration without any significant clinical finding on examination. Transthoracic echocardiography (TTE) revealed moderate pericardial effusion and later diagnosed as tubercular in etiology. Besides, TTE also showed an incidental finding of large left ventricular (LV) diverticulum in submitral region along the postero‐basal segment and left ventricular noncompaction (LVNC). Nonapical LV diverticulum is a rare variant of this uncommon congenital condition and its association with LVNC has not been reported in literature. Patient was discharged on antitubercular therapy for pericardial effusion and advised for 6 monthly follow‐up for diverticulum. 相似文献