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141.
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BACKGROUND: Epicardial pacing wires are routinely used for the diagnosis and treatment of bradyarrhythmias after cardiac surgery. The frequency of arrhythmias during removal of the wires is unknown, and methods of removal vary among institutions. OBJECTIVES: To describe the frequency of ventricular arrhythmias during removal of epicardial pacing wires from the right ventricle, to determine variables that are predictive of ventricular arrhythmias during wire removal, and to describe patients' perceptions of wire removal. METHODS: A convenience sample of 145 patients who had undergone cardiac surgery was studied during the course of 1 year. Electrocardiographic and vital signs were recorded throughout wire removal. Patients' records were reviewed for variables that could predict the occurrence of arrhythmias during wire removal: laboratory values, history of arrhythmias, medications, medical history, postoperative course, and pain reported by the patient. RESULTS: Sixty-six percent of patients had one premature ventricular contraction or more while the ventricular wires were being removed. Seven percent of patients had nonsustained ventricular tachycardia during wire removal. Patients who had repeat cardiac surgery had significantly more nonsustained ventricular tachycardia than did all other patients (P < .01). Only a history of heart failure (P < .02) was a significant predictor of premature ventricular contractions during wire removal. On a scale of 0 (no pain) to 10 (worst pain), the mean rating of pain intensity reported by patients was 2.39 (SD = 2.77). CONCLUSION: Patients may be at risk for ventricular arrhythmias during removal of epicardial pacing wires. Findings support the need for electrocardiographic monitoring while pacing wires are being removed.  相似文献   
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BACKGROUND: Animal studies have shown that motilin affects gall bladder motility. In humans, no effect has been shown, but erythromycin, a motilin receptor agonist, induces gall bladder emptying. AIMS: To explore the effect of increasing doses of exogenous motilin on gall bladder volume and antral contractility in the fasted state in humans. METHODS: After an overnight fast, eight healthy men received increasing intravenous doses of Leu13-motilin (KW-5139) or 0.9% NaCl in a double blind, randomised fashion. Gall bladder volume and antral contraction frequency were determined by ultrasonography. RESULTS: Infusion of motilin increased plasma motilin levels. Motilin induced a reduction in gall bladder volume of 8.0 (5.0)%, 17.1 (5.0)%, 18.5 (4.7)%, and 16.1 (4.9)% of baseline volume at the end of infusion of 2, 4, 8, and 16 pmol/kg/min respectively, compared with mean stable gall bladder volumes during placebo infusion (p < 0.05). Antral contraction frequency increased during motilin infusion, but not during placebo infusion (p < 0.05). CONCLUSIONS: Exogenous motilin reducted fasting gall bladder volume and increased antral contractions. After reaching maximal reduction, the gall bladder volume did not decrease further during continuous motilin infusion at higher doses and stayed at the same reduced volume. The degree of gall bladder volume reduction during motilin infusion mimicked gall bladder emptying preceding antral phase III activity of the migrating motor complex in humans. This study indicates that motilin may play a physiological role in the regulation of gall bladder emptying in the fasted state.  相似文献   
145.
24-hour monitoring of arterial pressure has been performed outpatiently in 20 subjects with mild or moderate essential hypertension using portable system Space Labs 90207. The design of the study implied 2 weeks of observation without any treatment followed by a 4-week course of lomir SRO-5 plus a 2-week course of lomir administration in a double dose. Control examination was performed at the end of each period. It was established that a 4-week lomir course results in a lowering of systolic and diastolic pressure by 8.4 + -2.1 and 6.9 + -1.3 mm Hg, respectively. Double-dose lomir was also effective: a fall in both systolic and diastolic pressure by 15.6 + -3.2 and 8.1 + -1.8 mm Hg, respectively, was achieved.  相似文献   
146.
The influence of green-yellow light of copper laser (mean power of impulse-periodic emanation 3 W, working density of power in experiment is 200 mW/cm2) on biochemical indices of chick embryo myoblasts and neuroblasts in primary culture was studied. The content of water extracted protein was found to increase progressively, the total and specific activities of creatine kinase elevated considerably in both the cell cultures under irradiation with the total doses equal to 3 and 15 J. However, with dose of 30 J these parameters corresponded to the level characteristic of nonirradiated cultures. Mechanisms of stimulating action of highly intensive laser emanation on cell functions are discussed.  相似文献   
147.
The graft-versus-host disease reaction is an immunologic consequence resulting from the grafting of immunocompetent cells from one individual to an immunocompromised host. The oral manifestations of this disease process include severe oral pain, xerostemia, ulcerative lesions, and mucositis. With appropriate history and diagnostic testing, these lesions can be differentiated from other oral diseases having similar clinical appearance.  相似文献   
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The 21-base pair synthetic DNA duplexes with basic 'pause-motif site ('CATGC') were ligated head-to-tail to produce linear and circular multimers. This also was done from other closely related sequences. Electrophoretic mobilities of the linear multimers in polyacrylamide gels were determined under the standard and modified conditions. We revealed that small linear multimers (approximately 90 bp) were characterized by comparable value of gel retardation relative to the well known curved DNA, while longer multimers (130 to approximately 170 bp) had only slightly expressed mobility anomaly. Nevertheless these multimers containing nontruncated 'pause-motif were capable of cyclization, in particular, formation of unusually small circles while truncated ones were not. We conclude that basic 'pause-motif site increases the closure ability while the multimers based on truncated 'pause motif fail to curve into the small circles. We tend to explain this situation as a result of intrinsic bending as well as the influence of the thermal fluctuations of DNA, the latter most probably can be associated with 'pause motif'. We have estimated the equilibrial and maximal bend angles per 10.5 bp to be 12 degrees to approximately 16 degrees and 32 degrees accordingly under experimental conditions of our study.  相似文献   
150.
Prophylaxis of postoperative thromboembolism is widely used because it has been shown to save lives and money. However, some surgeons are still reluctant to use general prophylaxis in high-risk orthopedic surgery. In total hip and total knee replacement the best method of prophylaxis is currently low molecular weight heparin started preoperatively and continued for 7 to 14 days or until the patient is fully ambulatory. A shorter prophylaxis period failed to be effective in an English study. At present there is an ongoing debate on the length of the period of risk, and whether there is a need for prophylaxis after discharge. Oral anticoagulation has been used for extended prophylaxis, but studies show that anticoagulant levels need to be monitored by repeated measurements by international normalized ratio. An alternative method would be to continue low molecular weight heparin injections for 4 to 5 weeks after surgery. No studies so far have evaluated the efficacy and safety of prolonged prophylaxis with low molecular weight heparin after discharge.  相似文献   
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