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991.
Treatment with tissue plasminogen activator (rt-PA) for acute stroke requires intensive care of the patient. The risk of thrombolytic therapy and the need for rapid interventions make it clear that the nursing role during this time is crucial. Nurses should be familiar with safe dosage and administration of rt-PA for stroke, which is clearly different than administration of rt-PA for myocardial infarction. Furthermore, thrombolytic stroke treatment must be accompanied by intensive neurological monitoring to observe for complications. Intracerebral hemorrhage is usually accompanied by an acute change in neurological status and vital sign instability. Intensive monitoring of neurologic condition, vital signs, cardiac status and other standard critical care practices must be initiated immediately to optimize patient outcome.  相似文献   
992.
The discussion by R. Schanzer (see ibid., vol.44, p.620-1, 1995) tries to correct the algorithms of P.K. Varshney, et al. (see ibid., vol.43, p.378-82, 1994) and K.K Aggarwal (see ibid., vol.37, p.65-9, 1988). But Schanzer doesn't explain why those algorithms have difficulty in calculating the maximum flow. This paper explains the problem and gives a correction of the algorithm so that the basic problem can be solved  相似文献   
993.
994.
The reduced ascorbic acid and β-carotene contents of “retail market-fresh” (RMF) and “fresh-frozen” (FF) green beans and broccoli in a simulated handling system were determined. Changes in ascorbic acid content in the two vegetables during a retail market period and frozen storage followed different patterns. In green beans, ascorbic acid content decreased during refrigerated storage for up to 7 days, but in broccoli there was a significant increase. Blanching resulted in a loss of approximately 40% of the ascorbic acid in broccoli. Ascorbic acid content of FF green beans stored at-20C for 16 weeks was approximately twice that in RMF green beans, but in FF broccoli stored under the same conditions it was only about half that of RMF broccoli. β-carotene content of green beans and broccoli did not change during either the retail market simulation of frozen storage and did not differ from that of fresh.  相似文献   
995.
The UV instruments described in part I of this paper have been applied for measurements of solar global UV radiation in three different wavelength regions (310–320 nm, 315–391 nm, and 296–388 nm). UV radiation values obtained since 1985 are analyzed. Different types of regression equations were compared as to how much information on UV radiation is contained in total global radiation measurements (400–2800 nm). Applying those regression equations allows us to estimate UV radiation from measurements of total global radiation, which are readily available.  相似文献   
996.
997.
InGaAs/GaAs(100) multiple-quantum-well-based inverted cavity asymmetric Fabry-Perot modulators are vertically integrated with GaAs/AlGaAs heterojunction phototransistors to yield all-optical photonic switches. The photonic switches using `normally on' modulator pixels exhibit an output on-off ratio of 12:1 with internal optical gain of 4 dB. The photonic switches using `normally off' modulator pixels yield similar contrast and gain, but exhibit intrinsic bistable behavior. The inverted cavity modulators employed permit utilizing the transparency of the GaAs substrate at the operating wavelength and offer advantages for fabricating large arrays for optical signal processing  相似文献   
998.
For pt.I see ibid., vol.17, no.1, p.95-101 (2002). This paper proposes a method for lateral stabilization of the levitated linear induction motor and also gives the analysis for calculating the stabilizing force in detail. The calculated force has been experimentally verified using the laboratory prototype described previously  相似文献   
999.
Theoretical studies point to significant improvements in the performance of semiconductor laser amplifiers by injecting carriers with pulsed electric currents of sub-nanosecond duration. A pulsed Fabry-Perot amplifier (FPA) is most sensitive to input lightwave at the instant the carrier density is crossing the critical region, and gives a sharply pulsed sampling effect on the input lightwave signal. Compared with a FPA operating at subcritical electron density, the pulsed amplifier gives much higher gain, peak power, and bandwidth. In fact, pulsed operation of a FPA is also expected to give significantly higher gain and about the same peak output power as a traveling wave amplifier. Pulsed operation also improves the performance of a traveling wave amplifier by attenuating its internally reflected waves  相似文献   
1000.
The ratio of the concentration (barrels of oil equivalent/sq. km) of accumulated oil in the richest sedimentary basin to that in the poorest basin, among those basins containing "giant" and "super-giant" fields, is more than 500 to 1. By contrast, the ratio of the richest to the poorest petroliferous basin in terms of average organic concentration may be less than 20 to 1. Such a large discrepancy between these two ratios suggests that organic concentration alone cannot account, for petroleum concentration in commercial reservoirs, because significant quantities of petroleum may be lost to the surface and be disseminated throughout the sedimentary sequence if the trapping conditions are not suitable. Most of this disseminated petroleum cannot be produced economically using present-day technology.
For a more accurate petroleum assessment, the Author stresses the importance of the efficiency of petroleum accumulation and preservation in commercial reservoirs: this may be evaluated as combining (a) the organic concentration of the source rock, (b) the duration of oil generation, (c) the thickness of the oil-generating "window", (d) the total geologic age involved, and (e) the fluid expulsion rate, and the presence or absence of undercompacted intervals.
Other parameters, such as the trap, reservoir and cap rock, and also the types of organic matter in the source rock, may have a great influence on the efficiency of petroleum concentrations in commercial reservoirs. However, most of these factors are of local significance, and thus are more difficult to generalise than those mentioned above in the context of the global distribution and concentration of oil reserves.  相似文献   
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