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R. Myles Riner Kathryn Maino Collins Garrett E. Foulke George V. Moorhead Phillip Terry 《The Western journal of medicine》1987,147(5):602-608
In a pilot project sponsored by the California State Emergency Medical Services Authority, validated, verifiable criteria were developed for the vertical categorization of hospital emergency services in 11 different groupings of medical and surgical emergencies. We describe the development of an assessment process and categorization criteria to identify the most appropriate receiving facility for interfacility transfer and, in selected instances, field triage of patients with different levels of severity of illness or injury. We propose that this facility assessment project be used in the critical care planning process for the eventual vertical categorization of hospital emergency services in California and as a template for similar projects in other states. 相似文献
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Summary Seasonal and diurnal gas exchange and water relations of Amyema linophyllum and its host Casuarina obesa were studied at Gingin Western Australia. As recorded elsewhere for other species of mistletoe, stomatal conductances and transpiration rates were consistently higher in parasite than host, but assimilation rates did not differ significantly between partners, and water use efficiency was accordingly substantially lower in the parasite. Parallel responses of the species to environmental conditions suggested closely coordinated stomatal behaviour. However, sunlit and artifically shaded clumps of Amyema maintained high leaf conductances even when foliage fell below turgor loss point, yet their tissue capacitance values indicated maintenance of greater tissue water reserves during stress than in the host. Pressure-volume relationships indicated that differences in tissue water relations were unlikely to contribute significantly to the observed gradient in leaf water potential between partners. An experiment measuring changes in water potential of freshly detached host: parasite systems cut with the host shoot end immersed in water indicated that the haustorial junction was the principal site of resistance to transpiration-driven water flow into the parasite. A parallel experiment on intact attached shoots with mistletoe clumps enclosed and darkened just before dawn, demonstrated that, once the host commenced rapid transpiration, the water potential gradient between partners became reversed. 相似文献
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Rooted cuttings ofCeanothus griseus varhorizontalis were irrigated with 0, 10, 20, 50, 75 or 100ppm nitrogen as NH4NO3 for eight weeks prior to inoculation with infectiveFrankia. After inoculation, half of the plants for each treatment nitrogen level continued to be irrigated with the preconditioning nitrogen level and half were given no more supplemental nitrogen. For plants continuously receiving nitrogen, nodule initiation (nodule number) was inversely correlated with increasing supplemental nitrogen levels, and suppressed above 50 ppm N. Leaf nitrogen above 2% in continuous-N plants correlated with greatly reduced or suppressed nodulation. Plants maintained after inoculation without supplemental nitrogen showed influence of the prior nitrogen treatment on nodulation. Preconditioning at 50 ppm and above greatly reduced the number of nodules formed. The evidence suggests that stored internal nitrogen can regulate nodulation.Plant biomass accumulated maximally when nodulation was suppressed, at 75 and 100 ppm supplemental N applied continuously. Internode elongation during the nodulation period occurred only on nodulated plants, or in the presence of supplemental N (10 ppm and above). 相似文献
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Timothy D. Noakes Estelle V. Lambert Michael I. Lambert Penelope S. McArthur Kathryn H. Myburgh A. J. Spinndler Benade 《European journal of applied physiology and occupational physiology》1988,57(4):482-489
Two studies were undertaken to characterize the effects of carbohydrate ingestion on fuel/hormone response to exercise and muscle glycogen utilization during prolonged competitive exercise. In study 1, eighteen subjects were divided into three groups, matched for maximum oxygen consumption (VO2max) and blood lactate turnpoint. All subjects underwent a 3-day carbohydrate (CHO) depletion phase, followed by 3 days of CHO loading (500-600 g.day-1). During the race, the groups drank either 2% glucose (G), 8% glucose polymer (GP), or 8% fructose (F). Muscle biopsies were performed before and after the race and venous blood was sampled before and at regular intervals during the race. In study 2, eighteen subjects divided into 2 matched groups ingested either a 4% G or 10% GP solution during a 56 km race. Despite significantly greater CHO ingestion by GP and F in study 1 and by GP in study 2, blood glucose, free fatty acids and insulin concentrations, muscle glycogen utilization and running performance were not different between groups. These studies show (i) that hypoglycaemia is uncommon in athletes competing in races of up to 56 km provided they CHO-load before and ingest a minimum of 10 g CHO.h-1 during competition; (ii) that neither the amount (10 g vs 40 g.h-1) nor the type of carbohydrate (G vs GP vs F) has any effect on the extent of muscle glycogen depletion or running performance in matched subjects racing over distances up to 56 km. 相似文献
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Andrew N. Webber Kathryn A. Platt-Aloia Robert L. Heath William W. Thomson 《Physiologia plantarum》1988,72(2):288-297
The detergent Tween-20 solubilized preferentially portions of the marginal regions of Spinacea oleracea L. thylakoid membranes and, thus, opened the inside of the grana to the external media. Differential centrifugation. following Tween-20 solubilization. enabled separate fractions of grana and stromal-exposed membranes to be isolated. Analysis of Tween-20 solubilized material, after pelleting all membrane material by centrifugation at 100 000 g, revealed polypeptides associated with the coupling factor (CF1 ) particles, cytochrome b6 /f and photosystem II complexes, suggesting that the marginal membranes contain these proteins. Concomitantly, the 100 000 g pellet was depleted in cytochrome b6 /f and P700, determined spectroscopically, Thus. our results reveal the margin to be a distinct membrane region, which does not contain the light-harvesting centers of photosystem II (LHC II). The implication of these results, in terms of the energetic interaction of components of granal and stromalexposed membrane regions, is discussed. 相似文献
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This research compares seven approaches from the literature to the selection of part types for simultaneous production over the next time horizon. A flexible approach to the selection of part types and the simultaneous determination of their mix ratios so as to balance aggregate machine workloads is presented. Constraints on tool magazine capacity are considered. Simulation studies are conducted on realistic, detailed models of flexible flow systems (FFSs) configured as pooled machines of equal sizes. The simulated settings are constructed to evaluate the impact of such factors as blocking, transportation, buffer utilizations, and fixture requirements and limitations of various types. One of the goals of this study is to encourage industry to relax, for those FMS types for which the procedure is appropriate, what is essentially an artificial constraint: that tool changing be isolated in time, to a period between batches. For other types of FMSs, batching may be appropriate. The results indicate that using the flexible approach enables the system to be more highly utilized. It is also observed that the batching approaches tend to require more fixtures of each type than the flexible approach. The system utilizations for the batching approaches seem to be more sensitive to restrictions on the number of fixtures of each type. Further research needs are also discussed. 相似文献