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31.
A C Neumann E Molyet C Teal G McCarty 《Journal of cataract and refractive surgery》1987,13(6):669-677
This report extends a previous paper on the various characteristics of the most popular phacoemulsification devices. An evaluation of 11 devices by ten different manufacturers was attempted. Only five manufacturers of six devices agreed to critical evaluation or reevaluation. As in the previous report, the devices were compared for level of patient safety, dependability, efficiency, ease of usage, and operating cost for the first 1,000 cases. At the completion of this study, we ranked the nine devices evaluated over the past 17 months as follows: (1) United Surgical (Optikon) Systems Plus, (2) Optical Micro Systems (OMS), (3) United Surgical (Optikon) Phacotron, (4) CooperVision 10,000, (5) Site XTR, (6) CooperVision KCP, (7) CooperVision 9001, (8) Phakosystems CES 4000 and (9) United Sonics. To enhance the usefulness of this consumer's guide, we asked 40 experienced cataract surgeons what they wanted in the "ideal" phacoemulsification device. The opinions of 27 who responded are included. 相似文献
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N Mutz M Neumann C H?rmann W Koller C Putensen G Putz H Benzer 《Der Anaesthesist》1990,39(10):535-539
In patients with multiple injuries, the development of permeability edema can be assumed. However, no uniform shape of this fluid accumulation can be found even in the presence of severe injuries. Based on the first clinical observations, our aim was to search for correlations between the development of extravascular lung water (EVLW) and the individual injury pattern in severely traumatized ICU patients. PATIENTS and METHODS. Our investigations were performed in 48 artificially ventilated ICU patients. According to the prevailing injury pattern patients were divided into three groups: group A: 18 patients (mean age: 32 years, mean Injury Severity Score (ISS) = 29) with isolated thoracic trauma; group B: 10 patients (mean age: 27 years, mean ISS = 42) with severe multiple trauma but without any thoracic injury; group C: 20 patients (mean age: 33 years, mean ISS = 43) with severe multiple trauma and concomitant thoracic trauma. In all patients (group A, B, C), EVLW was determined by means of a double indicator method on a daily basis from the patient's admission to the ICU (day of trauma) until day 10. Additionally, the hemodynamic parameters (heart rate, mean arterial pressure, mean pulmonary arterial pressure, pulmonary capillary wedge pressure and cardiac index) were determined at the same time. RESULTS. As shown in Fig 1, EVLW was slightly elevated on day 1. However, on day 2 EVLW decreased within normal values and remained in that range until the end of the observation period. On day 3 a slight and fleeting increase of EVLW, but within normal range, can be seen. In group B (Fig.2), EVLW can be observed within normal range within a period of 4 days. Starting from day 5 until day 7 a marked increase (p greater than 0.01) in EVLW can be seen. From that maximum point EVLW development reverses slightly until day 10--however, without returning to the normal range. In group C, a marked biphasic pattern can be seen due to EVLW maximum values on post-traumatic days 3 and 7. However, in this group the EVLW was in the pathological range during the whole observation period. No statistically significant differences could be seen, when looking at hemodynamic variables. CONCLUSION. Isolated thoracic trauma will not lead to a marked pathological elevation of EVLW within the lungs. Moreover, EVLW decreases rapidly within a short time period. Based on our results, it seems that severe extrathoracic injuries will intensify microvascular injury in the initial period, as shown in our patients in group C. Increase of EVLW at a later time (day 7), as observed in groups B and C, is possibly the expression of a mediator and activator-induced "septiformal" injury of the microvascular endothelium. This may be caused by the underlying massive peripheral soft-tissue trauma. Specific elevations of EVLW subsequent to the individual injury pattern can indicate that that process has begun and is responsible for the origin of the microvascular injuries. 相似文献
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The market for pharmacoeconomic analysis is rapidly expanding. Demand for experienced investigators seems to have outpaced the capacity of both the academic community and industry to train qualified practitioners. The result is that many professionals charged with producing and using cost-effectiveness and other drug-related economic evaluation studies may lack the basic skills required to carry out their duties. This, in turn, raises concerns regarding the credibility and integrity of the field as a whole. In our opinion, the adoption of self-imposed practice guidelines is a necessary first step in confronting these issues. However, the power of guidelines to promote responsible practice will be limited by the technical preparation of the analysts charged with adhering to them. A long term solution requires a collaborative commitment, on the part of both the academic community and the private sector, to targeted graduate training in pharmacoeconomic methods, and to the provision of ample opportunities for continuing professional education. 相似文献
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Neumann PJ 《The Journal of clinical psychiatry》1999,60(Z3):9-14; discussion 15
Because health care payers are increasingly interested in learning whether new treatments offer value for money, there has been an abundance of research into the cost-effectiveness of pharmacologic therapies in the United States. In the past few years, a number of studies comparing the cost-effectiveness of the conventional neuroleptics with that of the atypical antipsychotics have been published. Cost-effectiveness analyses show the relationship between the resources used (costs) and the health benefits achieved (effects) for a health or medical intervention compared with an alternative strategy. Ideally, the analyses can help decision makers improve the health of the population by better allocating society's limited health care resources. However, the extent to which cost-effectiveness data are actually used in decision making is unclear. The analyses are sometimes viewed with skepticism, in part because studies differ in their methodological approaches. Recently, the U.S. Panel on Cost-Effectiveness in Health and Medicine offered recommendations for standard methodological practices, which may help improve the quality of studies and the acceptability of the approach in the future. The issue is particularly important in light of new legislation governing how the Food and Drug Administration will regulate promotional claims made by drug companies regarding health economic information. 相似文献
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