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Objective: Descending and ascending aortomyoplasty are two surgical procedures intended to induce hemodynamic benefits similar to those of the intra-aortic-balloon-pump (IABP). To date, there have been no studies comparing the two surgical techniques. The objective of this study was to compare coronary blood flow augmentation and afterload reduction as produced by descending and ascending aortomyoplasty counterpulsation Methods: Twenty-two mongrel dogs (18–35 kg) underwent IABP application (n=7), descending (n=8), or ascending (n=7) aortomyoplasty. Left anterior descending (LAD) coronary artery blood flow was measured using a Transonic Doppler flow probe. Left ventricular pressure as well as aortic pressures proximal and distal to either the aortomyoplasty site or the IABP position were monitored continuously. Results: Descending aortomyoplasty induced higher elevation in the LAD blood flow during assisted beats (27% from 10.8±4 to 13.8±6 ml/min, P<0.001) than that induced by either ascending aortomyoplasty (19% from 11.7±5 to 14±5 ml/min, P<0.001) or IABP counterpulsation (18% from 8.6±3 to 10.2±4 ml/min, P<0.001). Conversely, while ascending aortomyoplasty reduced the left ventricular end-diastolic pressure by 16% (from 60±18 to 50±22 mmHg, P<0.001), similar to the 16% after load reduction achieved by the IABP counterpulsation, descending aortomyoplasty failed to induce afterload reduction. Conclusions: Descending aortomyoplasty produces higher coronary blood flow augmentation than either ascending aortomyoplasty or IABP. However, afterload reduction comparable to that achieved by IABP was observed only with ascending aortomyoplasty and not with descending aortomyoplasty.  相似文献   
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Mild head injuries are very common among young children. Often, these injuries are followed by a variety of subjective complaints termed posttraumatic syndrome. Posturography (balance test) was performed immediately after the trauma in 21 children who had sustained mild head injury. Significant difference in performance was observed in head-injured children in all subparts of the test as compared with a control group. We conclude that posturography may serve as a simple cost-effective method in qualifying the posttraumatic imbalance.  相似文献   
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Summary: One hundred five women with a documented pregnancy of 41 weeks' gestation or more, admitted for induction of labour by balloon catheter with extra-amniotic saline instillation, were retrospectively compared to 196 women admitted in spontaneous labour at the same gestational age, with regard to mode of delivery. The success rate of the induction group was 97.1%. The mode of delivery did not differ significantly between the 2 groups. The Caesarean section rates were 11.4% in the induction group versus 9.7% in the spontaneous group. The mode of delivery after induction of labour by balloon catheter with extra-amniotic saline instillation and simultaneously commenced intravenous oxytocin infusion, in pregnancies of 41 weeks or more, is similar to that of spontaneous deliveries at the same gestational age.  相似文献   
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We studied the effect of mast cell chymase on the thyroid cells in culture. Rat serosal mast cells, similar functionally to connective tissue mast cells, were obtained after lavage of the peritoneal cavity and lyzed by freezing. The resulting lysate was used as crude enzyme preparation. Mast cell chymase was purified from the crude preparation by anion exchange chromatography. Crude and purified chymase incubated with thyroid cells induced cellular retraction, the appearance of long processes and gradual cell detachment from the substratum. The effect of the enzyme was not cytotoxic. The immunofluorescence studies of thyroid cells showed a decreased amount of polymerized actin and tubulin after incubation with chymase. Neutral protease inhibitor abolished the effect of crude and purified chymase on thyroid cell morphology. The above findings suggest that mast cell chymase may have a function in the control of cell morphology and cell-matrix interaction.  相似文献   
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