Resting arterial H+ concentration ([H+]a) is in the nanomolar range (40±2 nm/L) while its production is in the millimolar range/min, with little variation from subject to subject. To determine the precision with which [H(+)]a is regulated during exercise, [H+]a, PaCO2 and ventilation (V˙(E)) were measured during progressively increasing work rate exercise in 16 normal subjects. (V˙(E)) increased with [H+]a, the latter attributable to PaCO2 increase below the lactic acidosis threshold (LAT) (ΔV˙(E)/Δ[H+]a ≈ 15 L min(-1) nanomol(-1)).
View Article and Find Full Text PDFThe detection and counting of transcripts within single cells via fluorescent in situ hybridization (FISH) has allowed researchers to ask quantitative questions about gene expression at the level of individual cells. This method is often preferable to quantitative RT-PCR, because it does not necessitate destruction of the cells being probed and maintains spatial information that may be of interest. Until now, studies using FISH at single-molecule resolution have only been rigorously carried out in isolated cells (e.
View Article and Find Full Text PDFCell motility proceeds by cycles of edge protrusion, adhesion, and retraction. Whether these functions are coordinated by biochemical or biomechanical processes is unknown. We find that myosin II pulls the rear of the lamellipodial actin network, causing upward bending, edge retraction, and initiation of new adhesion sites.
View Article and Find Full Text PDFThere is a clear relationship between single doses of ibuprofen over the range 50-400 mg and the peak analgesic effect and the duration of analgesia. The smallest clinically useful dose of ibuprofen is 200 mg. Ibuprofen 400 mg has been shown to be as effective as aspirin 600 or 900 mg/day in models of moderate pain but superior to aspirin or paracetamol in more sensitive models such as dental pain.
View Article and Find Full Text PDFOne hundred ninety-nine outpatients with pain following oral surgery were randomly assigned, on a double-blind basis, a single oral dose of diflunisal (500 or 1,000 mg), zomepirac sodium 100 mg, aspirin 650 mg, or placebo. Using a self-rating record, subjects rated their pain and its relief hourly for 12 hours after medication. Measures of total and peak analgesia were derived from these patients' subjective reports.
View Article and Find Full Text PDFWe have developed a method for measuring the efficacy of a single dose of an analgesic for 12 hours after administration to outpatients with postoperative oral surgery pain. Using a self-rating record, patients evaluate their pain and its relief for 12 hours after medication. We have used this method successfully in a series of three studies to compare diflunisal, a new nonsteroidal antiinflammatory analgesic, with placebo and aspirin 650 mg, acetaminophen 600 mg, propoxyphene napsylate 100 mg, or a combination of acetaminophen with either codeine 60 mg or propoxyphene 100 mg.
View Article and Find Full Text PDFThe analgesic efficacy of single 500 and 1,000 mg doses of diflunisal, a new nonsteroidal antiinflammatory analgesic, was compared in a double-blind study with acetaminophen 600 mg, the combination of acetaminophen 600 mg with codeine 60 mg, and placebo in 132 inpatients with postoperative pain. Using a self-rating record, patients rated their pain and its relief hourly for up to 12 hours after medication. Diflunisal 500 and 1,000 mg were significantly superior to placebo for every measure of total and peak analgesia, and a significant analgesic effect persisted for 8 hours.
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