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Simultaneous measurement of cardiac output distribution with 86Rubidium and 57Cobalt-tagged microspheres in rats implanted with liver tumors by intraportal injection of sarcoma cells enables quantitation of arterial and portal tumor circulation. The portal circulation was found to be increased in small tumors as compared to the liver, but as the tumor grew there was a decrease in the portal tumor circulation. When the tumor growth became massive even the total liver circulation was reduced, as measured with 133Xenon wash-out. All the tumors had increased arterial circulation. This arterial hyperperfusion was changed into ischemia when the liver artery was occluded through embolization with degradable microspheres. 相似文献
63.
Anatomic correction of transposition of the great vessels 总被引:1,自引:0,他引:1
AD Jatene VF Fontes PP Paulista LC Souza F Neger M Galantier JE Sousa 《Canadian Metallurgical Quarterly》1976,72(3):364-370
We present a new approach for anatomic correction of transposition of the great arteries. The two coronary arteries, with a piece of the aortic wall attached, are transposed to the posterior artery. The two aortic openings are closed with a patch. The aorta and pulmonary artery are transected, contraposed, ant then anastomosed. The interventricular septal defect is closed with a patch, through a right ventriculotomy approach, because the right ventricle is no longer part of the systemic circulation. Two patients, aged 3 months and 40 days weighing 4,200 and 3,700 grams, respectively, were operated upon with deep hypothermia and total circulatory arrest. There was good recovery from the operation, with normal cardiocirculatory conditions. Renal failure developed in the first patient, and she died on the third postoperative day. During this time the cardiocirculatory conditions were good. The second patient made an uneventful recovery. Hemodynamic studies 20 days after the operation showed complete correction of the malformation. Five and one-half months after the operation, he weighs 7,500 grams, and his development is very good. We believe that this operation will be reproducible by most cardiovascular septal defect and pulmonary hypertension. 相似文献
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A two-temperature model for a superconducting film under microwave irradiation is considered. From this simple model, the characteristic features of such a film are obtained; in particular, an increase of the gap parameter with a deficit of the phonon density above 2Δ is seen to occur under certain external conditions, as predicted by Eliashberg. Our numerical results and the gap measurements of Kommers and Clarke are in quantitatively good agreement. The two-temperature model is therefore a good approximation which allows one to obtain quantitative results rather easily. 相似文献
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Falls are frequent occupational accidents involving workers and lead to important social and economic consequences both for the individual and for the employer. Different factors can modify balance control and lead to falling, especially environment-related and individual factors. The literature would appear to indicate that there have been few studies on the intrinsic factors involving the mechanisms of generating falls. This review determines the main factors involved in the mechanisms of falling, whether related to the environment, work or the individual. Knowledge of the extrinsic and intrinsic factors contributing to the fall could allow securer environment planning and occupational conditions for employers, and the use of balance rehabilitation methods for individuals to reduce the risk of falls. 相似文献
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This paper addresses a real-life logistic problem arising in the hospital complex of Tours (France). The two-level vehicle routing problem has time windows, a heterogeneous fleet, and multi-depot, multi-commodity and split deliveries. The first level concerns the routing problem for a fleet of vehicles serving several hospital units that delivers medicines, clean linen, meals, various supplies, patient files and picks up waste and dirty linen. The second level concerns the problem of routing employees between buildings within a large hospital unit. Both levels are interconnected. In addition, decisions about sizing and planning the teams of drivers and warehouse employees have to be made. Two metaheuristic algorithms are proposed to solve the entire problem: a genetic algorithm and a tabu search. The algorithms are tested on 100 instances, randomly generated on the basis of real-life instances. 相似文献
70.
E. Zervas P. Dorlhène L. Forti C. Perrin J. C. Momique R. Monier 《Aerosol science and technology》2013,47(4):333-346
Abstract The Particulate Measurement Programme (PMP) works on the development of an improved method for the exhaust particulate matter (PM) measurement, which can include, if feasible and necessary, the measurement of particle number. The French PMP subgroup, composed of IFP, PSA Peugeot-Citroën, Renault, and UTAC, has defined a measurement protocol based on electrical low-pressure impactor (ELPI) and conducted an interlaboratory test to evaluate its performances. The technical program was based on tests carried out on three Euro3 passenger cars (one gasoline operating under stoichiometric conditions, one Diesel, and one Diesel equipped with a diesel particulate filter (DPF)) that were tested on the New European Driving Cycle (NEDC). The regulated pollutants are also measured, as indicators of test repeatability and good working conditions. The interlaboratory reproducibility value of the tunnel background tests is quite high (337%) due to low particle numbers. The repeatability values increase at low particle numbers independently of the vehicle used. On the NEDC, the reproducibility of total particle number is 59, 47, and 131% for the gasoline, Diesel, and DPF-equipped Diesel vehicles, respectively (compare to 67, 29, and 164% for PM collected on filters). These results show that the protocol used in this study allows a reliable measurement of exhaust particle number in the case of vehicles emitting at least two orders of magnitude more than the tunnel background. In the other cases, the measurement variability is too high, especially for regulatory purposes, without taking into account other metrological aspects, such as calibration. 相似文献