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Y S Gao T Nagao R A Bond W J Janssens P M Vanhoutte 《Journal of cardiovascular pharmacology》1991,17(6):964-969
Nebivolol is a new beta 1-antagonist that acutely reduces arterial blood pressure without depressing cardiac function. The present study was designed to determine the effect of nebivolol on coronary arteries. Rings of canine left anterior descending coronary (LAD) artery with or without endothelium were suspended in organ chambers and the isometric tension was recorded. In some experiments, the transmembrane potential of the smooth muscle cells was recorded by electrophysiological methods. During contractions to prostaglandin F2 alpha, nebivolol induced concentration-dependent relaxations of the coronary arteries. The enantiomer, l-nebivolol, also induced comparable relaxations; however, d-nebivolol induced smaller relaxations. The relaxations induced by nebivolol and its enantiomer were significantly larger in tissues with than in those without endothelium. The differences between tissues with and without endothelium were abolished by nitro-L-arginine (3 x 10(-5) M) or methylene blue (10(-5) M). The nebivolol-induced relaxations were not affected by indomethacin (10(-5) M), phentolamine (5 x 10(-6) M), propranolol (5 x 10(-6) M), or methysergide (3 x 10(-6) M). Nebivolol at a subthreshold concentration for inducing relaxation (3 x 10(-7) M) did not significantly affect endothelium-dependent relaxations to acetylcholine but potentiated ADP-induced endothelium-dependent relaxations. The potentiation is stereoselective for l-nebivolol. Nebivolol induced a small hyperpolarization of the coronary smooth muscle with endothelium (1 mV).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Dr. Cynthia L. Raehl Pharm.D. Dr. C. A. Bond Pharm.D. Mr. Michael E. Pitterle M.S. 《Pharmacotherapy》1998,18(2):302-326
To determine the extent of hospital-based clinical pharmacy services in 1995, we surveyed 1109 United States acute care, general, medical-surgical, and pediatric hospitals with 50 or more licensed beds. Fifteen clinical pharmacy services were assessed to determine pharmacists' specific patient care responsibilities. The percentage of hospitals offering services grew between 1992 and 1995: pharmacokinetic consultations (16% increase), drug therapy protocol management (15%), drug therapy monitoring (8%), drug counseling (13%), and parenteral-enteral nutrition team (6%). All other services increased 0–5%. Pharmacists conducted clinical research in 14% of hospitals, averaging 6.3 ± 22.1 protocols/department annually; total budget $96,219 ± $262,026. Patient-focused care predominated in 20% of hospitals, although most pharmacists reported to directors of pharmacy through traditional pharmacy department channels. Clinical pharmacy services continue to expand, with pharmacists providing higher-level direct patient care activities related to drug therapy management and monitoring. 相似文献
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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
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A new case of congenital dyserythropoietic anaemia, type III: studies of the cell cycle distribution and ultrastructure of erythroblasts and of nucleic acid synthesis in marrow cells. 下载免费PDF全文
S N Wickramasinghe T E Parry C Williams A N Bond M Hughes S Crook 《Journal of clinical pathology》1982,35(10):1103-1109
The clinical and laboratory findings in an asymptomatic 19-year-old Welshman with congenital dyserythropoietic anaemia (CDA) type III are described. The blood film showed macrocytosis and red cell fragmentation and there was biochemical evidence of intravascular haemolysis. The bone marrow showed erythroid hyperplasia, megaloblastic erythropoiesis and several giant multinucleate erythroblasts. Some mononucleate erythroblasts were large and had relative DNA contents of 4-8c and the bi- and multinucleate erythroblasts had total DNA contents of 2-16c. Some of the multinucleate erythroblasts displayed a variety of ultrastructural abnormalities, including marked differences in the appearances of the individual nuclei within the same cell. The marrow cells gave a normal deoxyuridine-suppressed value indicating that the megaloblastic changes were not caused by an impairment of the methylation of deoxyuridylate. The rates of incorporation of 14C-glycine and 14C-adenine into both the DNA and RNA of bone marrow cells were within the normal range. Furthermore, the average rate of elongation of newly-synthesised, 3H-thymidine-labelled daughter DNA strands, assessed by hydroxyapatite chromatography of alkali-denatured DNA was found to be normal. The results suggest that there is no impairment of DNA replication in the majority of the erythroblasts and that the abnormality of erythropoiesis resulted from disturbances during mitosis and the G2 phase. 相似文献
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William F Bond Lynn M Deitrick Darryl C Arnold Marianne Kostenbader Gavin C Barr Saron R Kimmel Charles C Worrilow 《Academic medicine》2004,79(5):438-446
PURPOSE: Recent literature defines certain cognitive errors that emergency physicians will likely encounter. The authors have utilized simulation and debriefing to teach the concepts of metacognition and error avoidance. METHOD: The authors conducted a qualitative study of an educational intervention at Lehigh Valley Hospital during academic year 2002-03. Fifteen emergency medicine residents--eight from postgraduate year three (PGY3) and seven from postgraduate year two (PGY2)--experienced a difficult simulator lab scenario designed to lead them into a cognitive error trap. The debriefing was a PowerPoint with audio format CD-ROM with a didactic on succinylcholine (15 minutes) and cognitive forcing strategies (30 minutes). After debriefing, residents were interviewed by an ethnographer with an 11-question (15-minute) interview and completed an eight-question written survey. RESULTS: The residents ranked this experience second only to direct patient care for educational effectiveness. Survey results (Likert scale, 1 = disagree completely to 5 = agree completely) included "Improved my ability to use succinylcholine" (mean = 4.73), "Improved my ability to diagnose and treat hyperkalemia" (mean = 4.6), and "Cognitive forcing strategies is a useful educational effort" (mean = 4.33). The major interview themes that evolved were that the simulation lab was a positive experience; succinylcholine knowledge was gained; mistakes caused reflection/motivation; the lab was stressful; attending feedback was desired; the lab was realistic; and cognitive forcing strategies were discussed. When asked what they learned, more of the PGY3s commented on cognitive strategies or heuristic techniques (six out of eight), whereas the PGY2s commented on knowledge gained about succinylcholine (five out of seven) and only one PGY2 mentioned cognitive strategies. CONCLUSION: Pilot data suggest that metacognitive strategies can be taught to residents, though they may be better understood by upper-level residents. 相似文献
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Association of high levels of serum antibody to staphylococcal toxic shock antigen with nasal carriage of toxic shock antigen-producing strains of Staphylococcus aureus 总被引:7,自引:4,他引:7 下载免费PDF全文
Forty-four asymptomatic male subjects were examined for their nasal carriage of strains of Staphylococcus aureus capable of producing staphylococcal toxic shock antigen (TSA), an exotoxin implicated in the pathogenesis of toxic shock syndrome. In addition, the levels of antibody to TSA in sera from these subjects were determined by an enzyme-linked immunosorbent assay. S. aureus was isolated from the anterior nares of 23 subjects. Of those 23 isolates of S. aureus, 9 were found to produce TSA. All individuals carrying strains of S. aureus capable of producing TSA had high to moderate levels of antibody to TSA. In contrast, those individuals carrying strains not producing TSA had levels of antibody to TSA ranging from high to nondetectable. A second examination of nasal samples from 42 of these subjects revealed that 86% of those carrying S. aureus initially still carried S. aureus after a period of 3 months; all subjects found to carry TSA-producing strains initially and that were examined a second time yielded TSA-producing strains once again. 相似文献
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