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51.
The authors previously described a method of windowing the femur that allowed good exposure for femoral cement removal and provided for reconstruction of the defect. Since that report, they have developed instrumentation to facilitate windowing of the femoral shaft. They describe its use in this report. 相似文献
52.
Bradykinin-induced plasma exudation in guinea-pig airways: involvement of platelet activating factor. 总被引:8,自引:6,他引:2 下载免费PDF全文
1. We studied the effect of bradykinin on plasma exudation in the airways of the anaesthetized guinea-pig in vivo. Tissue content of extravasated Evans blue dye was used as an index of protein exudation in the larynx, trachea, main bronchi and intrapulmonary airways (i.p.a.). 2. Bradykinin increased the content of Evans blue in all tissues studied in a dose-related manner. The response was greatest in the main bronchi and i.p.a., less in the trachea and least in the larynx. A dose of 47 nmol kg-1 was the lowest tested which caused significant (P less than 0.001) plasma exudation with increases in leakage above control values of 256% in the larynx, 405% in the trachea, 394% in the main bronchi and 485% in intrapulmonary airways. 3. Leakage was significantly (P less than 0.05) increased above control values by 1 min after bradykinin (47 nmol kg-1) in the main bronchi and intrapulmonary airways and was maximal in all airways 5 min after bradykinin. Although reduced by 15 min, the tissue content of dye was still significantly (P less than 0.05) increased 2 h after bradykinin. 4. The prolonged tissue dye retention was due to a later phase of slow and maintained exudation preventing full clearance of dye after the initial response. 5. The initial phase of leakage was partially attenuated by the platelet activating factor (PAF) receptor antagonists WEB 2086 or BN 52021, by indomethacin or by inhibiting sensory nerve activation by opioid anaesthesia: it was not affected by mepyramine and cimetidine nor by the sulphidopeptide leukotriene receptor antagonists FPL 55712 or ICI 198,615.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Failure of nitric oxide donors to alter arrhythmias induced by acute myocardial ischaemia or reperfusion in anaesthetized rats. 总被引:3,自引:3,他引:0 下载免费PDF全文
1. The aim of the present studies was to examine the effects of nitric oxide donors on arrhythmias induced by coronary artery occlusion and reperfusion, and on cardiac cyclic nucleotides. Experiments were performed in pentobarbitone-anaesthetized rats prepared for occlusion of the left coronary artery. 2. Sodium nitroprusside (0.1, 0.3 and 1 microgram kg-1 min-1) had no significant effects on the incidence of ventricular tachycardia, total ventricular fibrillation or the mortality resulting from 25 min of acute myocardial ischaemia when compared with values in controls. In addition, there was no alteration in the number of ventricular premature beats that occurred in survivors. 3. 3-Morpholinosydnonimine-N-ethylcarbamide (SIN-1, 10, 20 and 40 micrograms kg-1 min-1) caused marked hypotension but did not alter the incidence or severity of ischaemia-induced arrhythmias. In rats subject to abrupt reperfusion after 5 min of myocardial ischaemia, lower doses of SIN-1 (1, 3 and 10 micrograms kg-1 min-1) still caused significant reductions in systolic and diastolic blood pressure but were devoid of antiarrhythmic activity. 4. In separate experiments in sham-operated rats, sodium nitroprusside (1 microgram kg-1 min-1), isosorbide dinitrate (30 and 60 micrograms kg-1 min-1) and SIN-1 (20 and 40 micrograms kg-1 min-1) had no significant effects on cardiac cyclic GMP content. 5. These results indicate that nitric oxide donors do not alter arrhythmias induced by acute coronary artery occlusion or reperfusion in anaesthetized rats.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Ralph Worfolk Graham R. Barnes 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1992,90(3):589-598
Summary Independent target and background motions have been used to generate conflicting activity within the pursuit and optokinetic systems. Subjects were required to pursue a small target against a structured background which moved independently. Selective enhancement of the response to the target generated high-gain active pursuit which dominated the eye movements. Passive eye movements induced during relative target and background motion are not normally directly quantifiable due to their low gain. By reducing the gain of the active pursuit optokinetically induced eye movements were enhanced and quantified. Three techniques are described for degrading active pursuit: tachistoscopic, eccentric and pseudorandom methods of target presentation. Our results demonstrate the synchronous input of active and passive eye movement drives to the oculomotor system and illustrate their interaction. 相似文献
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A hand-held spirometer, the Respiradyne (R), was evaluated for the measurement of forced expiratory volume in the first second (FEV1), forced vital capacity (FVC) and peak expiratory flow rate (PEFR) by comparing it with a Vitalograph spirometer (V) and a Wright's peak flow meter (W) in 70 subjects (normals and patients). The results showed close agreement for FEV1; r = 0.99, R = 0.961V + 0.03 X 10(-5) and FVC; r = 0.99, R = 1.003V-0.044. Results for PEFR using the Respiradyne were generally higher than with the peak flow meter; r = 0.98, R = 1.151W-17.576. The Respiradyne is portable and simple to operate and may be suited to use in a variety of non-laboratory situations. 相似文献
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The stability of bendrofluazide 1.25 mg in capsules was studied. The formulation is intended to provide a unit dose powder for administration by dispersing the contents in liquid. The capsules were prepared from ground bendrofluazide tablets 5 mg from two different manufacturers, diluted with lactose and packed manually by weight into hard gelatin capsule shells. The capsules were stored at ambient temperature exposed to light or 75% relative humidity, and at 45 or 60C. The ambient temperature and 60C conditions were studied for up to 1 year. Bendrofluazide was determined by a stability-indicating HPLC method. The capsule contents remained easy to disperse in liquid by the end of the study. The weight of contents which could be extracted from the capsules also remained satisfactory. A 7-month storage life at ambient temperature would be feasible, based on the lower 95% confidence limits of the time to 5% degradation. 相似文献