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21.
Norman R. I.; Hirst R.; Appadu B. L.; McKay M.; Bradley P.; Griffiths R.; Rowbotham D. J. 《British journal of anaesthesia》1997,78(3):290-295
The decrease in membrane microviscosity of erythrocyte ghosts in the
presence of clinically relevant concentrations of seven inhalation
anaesthetic agents was studied using fluorescence polarization anisotropy
of the membrane incorporated fluorescent probes 1,6-diphenyl-
1,3,5-hexatriene and 1-[4-trimethylammoniumphenyl]-6-phenyl-1,3,5-
hexatriene. All anaesthetic agents produced a dose-dependent decrease in
anisotropy of both probes, indicating decreased membrane microviscosity.
The reduction in anisotropy measured at the minimum alveolar concentration
(ED50) for anaesthesia was related inversely to the anaesthetic potency of
the agent and was directly proportional to the hypothetical concentration
of agent in the membrane calculated from lipid-water partition
coefficients. These findings do not support the hypothesis that volatile
anaesthetic agents act by increasing membrane microviscosity of the bulk
lipid bilayer to produce anaesthesia.
相似文献
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J D Bradley K D Brandt B P Katz L A Kalasinski S I Ryan 《The Journal of rheumatology》1992,19(12):1950-1954
Our randomized double blinded comparison of acetaminophen versus analgesic and antiinflammatory doses of ibuprofen in the treatment of 182 subjects with knee osteoarthritis (OA) systematically evaluated soft tissue tenderness and joint swelling. Improvement in these signs of joint inflammation was associated with lessening of disability (p = 0.02), and reduction in rest pain (p = 0.07), but not with the drug treatment regimen. Thus, joint tenderness and swelling, presumptive evidence of synovitis, may not be a priori indications for use of an antiinflammatory drug, or predict greater responsiveness to treatment with an antiinflammatory drug than to a pure analgesic, in symptomatic treatment of patients with knee OA. 相似文献
24.
Richard N. Bradley 《Disease Management & Health Outcomes》2003,11(5):321-325
Acute stroke affects large numbers of people worldwide. It causes significant morbidity and mortality. Data support the hypothesis that the public is not familiar with either the risk factors or the signs of stroke. Educating the public about stroke may result in a lower incidence of the disease as individuals modify their risk factors, and in improved outcomes as a result of reductions in delays to treatment. There is clear and convincing evidence that reducing delays to treatment of patients with acute stroke results in improved outcomes. Public education programs should be broad-based, tailored to individual audiences, and carry a common theme. 相似文献
25.
B G Campling A C Haworth H M Baker D L Greer J J Holden E C Bradley J Pym D F Dexter 《Cancer》1992,69(8):2064-2074
The establishment and characterization of 11 human lung cancer cell lines are described in this article. Nine of these cell lines were established over a 5-year period, from 1983 to 1988, from patients treated at the Kingston Regional Cancer Centre. These include eight definite or probable small cell lung cancer (SCLC) lines and one adenocarcinoma line. In addition, two other SCLC cell lines were characterized. All of the lines have been in continuous culture for more than 2 years. The clinical histories of the patients from whom the cell lines were derived are outlined here. Several features of the cell lines are presented, including the following: (1) a comparison of the histologic features of the cell lines with the original biopsy specimens; (2) the expression of various markers, including cytokeratin, carcinoembryonic antigen, calcitonin, and neuron-specific enolase; (3) activities of the enzymes l-dopa decarboxylase and the brain isoenzyme of creatine kinase; (4) growth characteristics; (5) cloning efficiency in soft agar; (6) tumorigenicity in nude mice; and (7) cytogenetic studies. These cell lines, obtained directly from patients with a spectrum of drug-sensitive and drug-resistant tumors, will be valuable in vitro models of sensitivity and resistance to chemotherapy in lung cancer. 相似文献
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Aseptic loosening is the most common mode of failure for total knee replacements. Component breakage is rare, usually attributable to errors of design or manufacture. A case is presented in which rotational malplacement of the femoral component resulted in accelerated wear and eventual fracture of the polyethylene tibial component. 相似文献
28.
T M Clay M R Howard J L Bidwell E A Bidwell P A Raymond J E Evans B A Bradley 《European journal of immunogenetics》1991,18(1-2):97-104
Thirty-seven DR4-positive patient-unrelated bone marrow donor pairs previously DR/DQ restriction fragment length polymorphism (RFLP) typed and tested in mixed lymphocyte culture (MLC), have been DR4-Dw subtyped retrospectively using sequence specific oligonucleotide probes. We found that DR4-Dw subtyping substantially increased the accuracy of pre-MLC matching and could potentially accelerate donor searches by avoiding unnecessary MLC tests on Dw-mismatched donors. 相似文献
29.
Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance 总被引:3,自引:0,他引:3
Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy. 相似文献
30.
Gertie J. Oostingh Hugh F. S. Davies Kerrie C. G. Tang J. Andrew Bradley Craig J. Taylor 《American journal of transplantation》2002,2(3):267-273
We have previously shown that IgG HLA specific antibodies in the sera of highly sensitised patients awaiting renal transplantation can cross-react with swine leukocyte antigens (SLA). In this study we determined the frequency of patient serum IgG HLA specific antibody binding to a porcine lymphocyte panel and the likelihood of locating a cross-match negative pig donor for sensitised patients. Serum samples (n = 82) were obtained from 35 sensitised [current IgG panel reactive antibodies (PRA) > 10%] and seven nonsensitised patients awaiting renal transplantation at Addenbrooke's Hospital, Cambridge, UK. Fifty sera had IgG HLA specific PRA of 11-84%, 20 had IgG PRA of >84% and 12 had 0% PRA (negative controls). Sera were absorbed with porcine erythrocytes to remove xenoreactive natural antibodies and tested for cross-reactive IgG HLA specific antibody binding by flow cytometry against a panel of porcine lymphocytes obtained from 23 human decay accelerating factor (hDAF) transgenic pigs. A total of 1,884 cross-match combinations were tested and 369 (20%) gave a positive porcine lymphocyte cross-match. For sera from sensitised patients with IgG PRA (11-64%), only 6 of 805 (0.75%) cross-match tests were positive. In contrast, for sera from patients with high IgG PRA (>64%), 363 of 805 (45%) cross-match tests were positive (p < 0.0001). There was no difference in the frequency of positive cross-matches between patient sera with IgG PRA 65-84% and highly sensitised patient sera with IgG PRA 85-100% [156/345 (45%) vs. 207/460 (45%)]. This study demonstrates that only patient sera with broadly reactive IgG HLA specific PRA (>64%) cross-react with porcine lymphocytes. If future clinical trials of xenotransplantation are undertaken, it may be of value to select a cross-match-negative pig organ donor for such patients. 相似文献