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31.
R Dixon AM Hughes K Nairn M Sellers JV Kemp RA Yates 《Cephalalgia : an international journal of headache》1998,18(7):468-475
Zolmitriptan (ZomigTM ) is a 5HT1B/1D agonist which has the ability to cross the intact blood-brain barrier to access central as well as peripheral receptors. Because of the potential for central nervous system side effects, this randomized, double-blind, placebo-controlled, 6-period crossover study evaluated the effects of 2.5 and 5 mg doses of zolmitriptan on psychomotor performance and investigated any pharmacodynamic or pharmacokinetic interaction with diazepam. Twelve healthy volunteers received the following "treatments" as single doses: zolmitriptan 2.5 mg, zolmitriptan 5 mg, diazepam 10 mg, zolmitriptan 2.5 mg+diazepam 10 mg, zolmitriptan 5 mg+diazepam 10 mg and placebo. Pre-dose and at 1, 4, 8, and 24 h post-dose, the following validated battery of psychomotor tests was performed: Bond-Lader visual analogue scales (calmness, contentedness, and alertness factors), critical flicker fusion test, choice reaction time (recognition, motor, and total reaction times), finger-tapping test, number cancellation test and digit symbol substitution test. Plasma concentrations of zolmitriptan, its active metabolite, and diazepam and its active metabolites were measured at the same timepoints. Zolmitriptan 2.5 and 5 mg had no effect on psychomotor function when given alone. In contrast, diazepam 10 mg had profound effects, consistent with its sedative properties, but there was no synergism on concomitant administration of either dose of zolmitriptan. Plasma concentrations of zolmitriptan, diazepam, and their respective active metabolites were similar when the two drugs were given alone or in combination. 相似文献
32.
Chest radiographs and chest computed tomography (CT) scans were compared in 203 patients with newly diagnosed Hodgkin disease. The incidence of positive findings was tabulated from six intrathoracic lymph node groups, lung parenchyma, pericardium, pleura, and chest wall. The discordant cases were assessed to determine impact on clinical management. The CT scans provided additional evidence of disease involvement, ranging from 0% to 15% at each of the designated anatomic sites. Treatment was altered in 9.4% of all patients (19 of 203), including 13.8% (nine of 65) of those undergoing radiation therapy alone and 8.2% (ten of 122) of those undergoing combined-modality treatment. We conclude that routine chest CT examinations are valuable in the clinical management of those patients for whom radiation therapy is planned. 相似文献
33.
Anucha Apisarnthanarak Marilyn Jones Brian M Waterman Cathy M Carroll Robert Bernardi Victoria J Fraser 《Infection control and hospital epidemiology》2003,24(1):31-36
OBJECTIVE: To characterize risk factors for surgical-site infection after spinal surgery. DESIGN: A case-control study. SETTING: A 113-bed community hospital. METHOD: From January 1998 through June 2000, the incidence of surgical-site infection in patients undergoing laminectomy, spinal fusion surgery, or both increased at community hospital A. We compared 13 patients who acquired surgical-site infections after laminectomy, spinal fusion surgery, or both with 47 patients who were operated on during the same time period but did not acquire a surgical-site infection. Information collected included demographics, risk factors, personnel involved in the operations, length of hospital stay, and hospital costs. RESULTS: Of 13 case-patients, 9 (69%) were obese, 9 (69%) had spinal compression, 5 (38.5%) had a history of tobacco use, and 4 (31%) had diabetes. Oxacillin-sensitive Staphylococcus aureus (6 of 13; 46%) was the most common organism isolated. Significant risk factors for postoperative spinal surgical-site infection were dural tear during the surgical procedure and the use of glue to cement the dural patch (3 of 13 [23%] vs 1 of 47 [2.1%]; P = .02) and American Society of Anesthesiologists risk class of 3 or more (6 of 13 [46.2%] vs 7 of 47 [15%]; P = .02). Case-patients were more likely to have prolonged length of stay (median, 16 vs 4 days; P< .001). The average excess length of stay was 11 days and the excess cost per case was $12,477. CONCLUSION: Dural tear and the use of glue should be evaluated as potential risk factors for spinal surgical-site infection. Systematic observation for potential lapses in sterile technique and surgical processes that may increase the risk of infection may help prevent spinal surgical-site infection. 相似文献
34.
RETROPERITONEAL MUCINOUS CYSTADENOMA PRESENTING AS A RENAL CYST 总被引:4,自引:0,他引:4
35.
Nancy Ballard Lois Robley Darcy Barrett Danielle Fraser Inocencia Mendoza 《American journal of critical care》2006,15(1):86-94; quiz 95
BACKGROUND: Neuromuscular blocking agents used for therapeutic purposes, such as facilitating mechanical ventilation and relieving life-threatening agitation, paralyze patients but leave them fully conscious. Aggressive sedation or analgesia is necessary to reduce awareness, relieve fear, produce comfort, decrease anxiety, induce unconsciousness, and minimize possible complications such as posttraumatic stress syndrome. Little information is available on the extent to which patients experience awareness during therapeutic paralysis. OBJECTIVES: To determine and describe the remembered experiences of critical care patients who were given neuromuscular blocking agents and sedatives and/or analgesics to facilitate mechanical ventilation, improve hemodynamic stability, and improve oxygenation. METHODS: A phenomenological approach with in-depth interviews with 11 patients was used. Data were analyzed by using the constant comparative approach. RESULTS: A total of 4 themes and 3 subthemes were identified. The first theme was back and forth between reality and the unreal, between life and death; the subtheme was having weird dreams. The second theme was loss of control; the 2 subthemes were (1) fighting or being tied down and (2) being scared. The third theme was almost dying, and the fourth theme was feeling cared for. CONCLUSIONS: Patients can remember having both negative and positive experiences during neuromuscular blockade. Steps to improve the experiences of patients receiving neuromuscular blockers include improving assessment parameters, developing and using sedation/analgesia guidelines, and investing in quality improvement programs to provide assessment of awareness during therapeutic paralysis and follow-up and referral as necessary. Ways to decrease the use of neuromuscular blockers would also be useful. 相似文献
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39.
Characterization of RAFTK, a novel focal adhesion kinase, and its integrin-dependent phosphorylation and activation in megakaryocytes 总被引:19,自引:3,他引:16
We have recently isolated a cDNA encoding a novel human intracellular tyrosine kinase, termed RAFTK (for a related adhesion focal tyrosine kinase). The RAFTK cDNA, which encodes a polypeptide of 1,009 amino acids, shares 65% homology to the focal adhesion kinase (FAK), including several consensus motifs. In this report, we describe the biochemical characterization and functional analysis of the RAFTK protein. Coexpression of RAFTK and FAK proteins in megakaryocytic cells and blood platelets was observed. Using a specific antibody to RAFTK and the monoclonal antibody 2A7 to FAK, FAK and RAFTK could be distinguished antigenically. RAFTK had intrinsic tyrosine kinase and autokinase activities. It was phosphorylated on tyrosine in growing cultures of COS cells transfected with the pCDNAIII/flag-RAFTK expression vector containing the RAFTK cDNA ligated with the 8 amino acid flag peptide sequence. Similar to FAK, dephosphorylation of RAFTK was observed when adherent transfected COS cells were detached. Phosphorylation was regained upon replating of these cells on the fibronectincoated dishes. Analysis of tyrosine-phosphorylated RAFTK from adherent transfected COS cells showed that the Src homology 2 (SH2) domains of the Src and Fyn protein kinases as well as the Grb2 adaptor protein were able to specifically associate with RAFTK. Tyrosine phosphorylation of endogenous RAFTK was observed upon fibronectin-induced activation of human megakaryocytic cells. Furthermore, colocalization of RAFTK protein with vinculin, a focal adhesion protein, was observed by confocal microscopy in focal adhesion- like structures in adherent CMK cells and in transfected pCDNAIII/flag- RAFTK COS cells upon fibronectin activation. These data suggest that RAFTK is a novel member of the FAK family, that it localizes to focal adhesion-like structures in CMK megakaryocytic cells, that it participates in integrinmediated signaling pathways in megakaryocytes, and that it is able to associate with the tyrosine kinases Src and Fyn as well as the adaptor protein Grb2 via SH2-phosphotyrosine interactions. 相似文献
40.
L. J. Dowie J. E. Smith A. J. MacGilchrist R. Fraser J. W. Honour J. L. Reid C. J. Kenyon 《European journal of clinical pharmacology》1988,35(6):625-629
Summary The site of omeprazole inhibition of adrenal steroidogenesis has been sought in vivo by analyzing the patterns of urinary steroid metabolite excretion after 6 days of treatment with placebo/omeprazole.Excretion rates of androsterone, aetiocholanolone, dehydroepiandrosterone, 11 hydroxyandrosterone, tetrahydrocortisone, tetrahydrocortisol and cortolone were reduced, indicating a block at an early step in steroidogenesis, possibly cholesterol side-chain cleavage. In vitro studies have confirmed this finding by measuring conversion of added precursors to cortisol in isolated bovine adrenocortical cells. Cortisol synthesis from added 20 hydroxycholesterol was inhibited by 83% in the presence of 100 µg omeprazole/ml. Conversion from pregnenolone and progesterone and their 17 hydroxylated derivatives was inhibited by 20–40% whereas cortisol production from added 11 deoxycortisol was not affected.These data suggest that omeprazole primarily inhibits cholesterol cleavage and does not inhibit 3 hydroxysteroid dehydrogenase, 17 hydroxylase or 11 hydroxylation; 21 hydroxylase activity may be marginally attenuated. 相似文献