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91.
RD Anderson EM Ohman DR Holmes I Col AL Stebbins ER Bates RJ Stomel CB Granger EJ Topol RM Califf 《Canadian Metallurgical Quarterly》1997,30(3):708-715
OBJECTIVES: We sought to examine the use, complications and outcomes with early intraaortic balloon counterpulsation (IABP) in patients presenting with cardiogenic shock complicating acute myocardial infarction and treated with thrombolytic therapy. BACKGROUND: The use of IABP in patients with cardiogenic shock is widely accepted; however, there is a paucity of information on the use of this technique in patients with cardiogenic shock who are treated with thrombolytic therapy. METHODS: Patients who presented within 6 h of chest pain onset were randomized to one of four thrombolytic regimens. Cardiogenic shock was not an exclusion criterion, and data for these patients were prospectively collected. Patients presenting with shock were classified into early IABP (insertion within one calendar day of enrollment) or no IABP (insertion on or after day 2 or never). RESULTS: There were 68 (22%) IABP placements in 310 patients presenting with shock. Early IABP use occurred in 62 patients (20%) and none in 248 (80%). Most IABP use occurred in the United States (59 of 68 IABP placements) involving 32% of U.S. patients presenting with shock. Despite more adverse events in the early IABP group and more episodes of moderate bleeding, this cohort showed a trend toward lower 30-day and 1-year mortality rates. CONCLUSIONS: IABP appears to be underutilized in patients presenting with cardiogenic shock, both within and outside the United States. Early IABP institution is associated with an increased risk of bleeding and adverse events but a trend toward lower 30-day and 1-year all-cause mortality. 相似文献
92.
MJ Holmes DS Diack RA Easingwood JP Cross B Carlisle 《Canadian Metallurgical Quarterly》1997,31(1):115-122
Fluoxetine is a 5-hydroxytryptamine (5-HT, serotonin)-selective reuptake inhibitor (SSRI) and is one of the main drugs used for the treatment of depression. Because it takes 2 to 3 weeks of treatment before clinical efficacy is manifest, the acute actions of fluoxetine cannot account for the clinical actions of the drug. The chronic effects of fluoxetine have not been completely delineated. The experiments detailed here investigate the chronic effects of fluoxetine on 5-HT and gamma-aminobutyric acid (GABA) receptor-mediated actions using intracellular recording techniques in hippocampal brain slices. Rats were treated with fluoxetine for 3 weeks via osmotic minipumps implanted s.c. Fluoxetine and norfluoxetine plasma levels were determined. The hippocampal pyramidal cell characteristics and the 5-HT1A and GABA(B) receptor-mediated hyperpolarization were measured in the CA1 and the CA3 subfields. The 5-HT4 receptor-mediated decrease in the slow afterhyperpolarization amplitude was also recorded in area CA1. The time constant, magnitude of the change in resistance during 300-ms hyperpolarizing current pulses and half-decay time of the sAHP were altered by chronic fluoxetine treatment in area CA1 pyramidal cells. No changes were seen in any of the active or passive membrane properties of the CA3 hippocampal pyramidal cells. Fluoxetine treatment increased the potency of 5-HT for the 5-HT1A receptor-mediated hyperpolarization in area CA1, but not area CA3, and decreased the potency of baclofen for the GABA(B) receptor-mediated hyperpolarization in area CA1, but not area CA3. The characteristics of the concentration-response curve for the 5-HT-mediated decrease in sAHP amplitude in area CA1 were not altered by fluoxetine treatment. Chronic fluoxetine selectively and differentially altered the cell characteristics and the 5-HT1A and GABA(B) receptor-mediated responses in area CA1 of the hippocampus, which forms the final common output of the hippocampus. 相似文献
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Of 2774 consecutive, prospectively documented fractures of the distal radius, 225 (8 per cent) occurred as sports injuries, mainly in young men. Soccer produced the greatest number of wrist fractures with 112 cases (50 per cent). Skiing, dancing and rugby caused 12 per cent, 9 per cent and 7 per cent of all sporting wrist fractures respectively. Skiing, horseriding and dancing consistently resulted in more complex fractures. In soccer, synthetic pitches increased the likelihood of a fracture following a fall by a factor of five. Twelve per cent of fractures required further treatment because of instability leading to redisplacement. The complication rate was 14 per cent with the majority being cases of malunion (12 per cent). Of the 131 patients who returned a questionnaire, 72.5 per cent had returned to their original sport. This was influenced mainly by the patient's age and pre-injury standard of competition. 相似文献
96.
Ligand-induced translocation of epidermal growth factor receptors (EGF-R) to the nucleus of NR6/HER fibroblasts has been studied by immunoelectron microscopy. Following treatment of NR6/HER cells with epidermal growth factor (EGF) for 1 h, there was a decrease in EGF-R labeling at the plasma membrane and a corresponding increase in EGF-R in the nucleus. This was preceded by a rapid and sustained increase in nuclear phosphotyrosine content, detectable within 2 min of EGF treatment. EGF-R translocation into the nucleus was completely prevented by 18 h serum starvation prior to treatment with EGF. These results indicate that translocation of EGF-R to the nucleus is a controlled process and they suggest that EGF-R may directly influence nuclear function. 相似文献
97.
Previously we found that rat mesangial cells express 3CH134/CL100 protein-tyrosine phosphatase (PTPase) in response to reactive oxygen intermediates (ROIs), and we now extend these studies to glomerulonephritis (GN), where ROI have been demonstrated to play a role. The rat homologue of 3CH134/CL100 was cloned from a rat macrophage cDNA library. The rat 3CH134/CL100 mRNA was strongly induced in the lung, liver, and heart the first day after birth, suggesting that hyperoxic adaption might be involved in the induction of the PTPase mRNA. In anti-glomerular basement membrane (GBM) antibody (Ab) GN in rats, the 3CH134/CL100 PTPase mRNA was expressed in glomeruli as early as 30 minutes after anti-GBM Ab injection. The 3CH134/CL100 mRNA expression was modulated by the ROI scavenger dimethylthiourea (DMTU), indicating that its induction was ROI related. In contrast to the glomerular lesion, PTPase mRNA expression was not induced in experimental tubulointerstitial nephritis. In situ hybridization suggested that mesangial and some infiltrating cells were the major glomerular cell sources of the PTPase mRNA. These results indicate that rat CCH134/CL100 PTPase is actively induced in glomeruli as part of an acute immune injury at least in part related to oxidative stress. PTPase induction in GN and potentially other forms of inflammation may play an important regulatory role in protein kinase signaling pathways. 相似文献
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CB Sudhakar M Al-Hakeem JD MacArthur BE Sumpio 《Canadian Metallurgical Quarterly》1997,92(6):1053-1054
In summary, we report two cases of mesenteric ischemia following cocaine abuse in young women. In such cases it is always difficult to prove a direct causal relationship between the abuse of cocaine and mesenteric ischemia. Both our patients were relatively young (in their thirties) and did not have any history of atherosclerosis, and their urine toxicity screens were positive for the use of cocaine. Cocaine-related hospital visits are on the increase. Mesenteric ischemia should be considered in the differential diagnosis when evaluating a young patient with a history of cocaine abuse presenting with an acute abdomen. 相似文献
100.