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91.
Microsphaeropsis arundinis is an anamorphic fungal plant inhabitant belonging to the form class Coelomycetes. We describe two cases of M. arundinis soft tissue infections in immunosuppressed patients. This organism has not previously been described as causing disease in humans. It was identified on the basis of its typical ostiolate pycnidial conidiomata, ampulliform conidiogenous cells, and small, smooth-walled, brown, cylindrical conidia.  相似文献   
92.
93.
PURPOSE: This paper investigates the impact of quality-of-life adjustment on cost-effectiveness analyses, by comparing ratios from published studies that have reported both incremental costs per (unadjusted) life-year and per quality-adjusted life-year for the same intervention. METHODS: A systematic literature search identified 228 original cost-utility analyses published prior to 1998. Sixty-three of these analyses (173 ratio pairs) reported both cost/LY and cost/QALY ratios for the same intervention, from which we calculated medians and means, the difference between ratios (cost/LY minus cost/QALY) and between reciprocals of the ratios, and cost/LY as a percentage of the corresponding cost/QALY ratio. We also compared the ratios using rank-order correlation, and assessed the frequency with which quality-adjustment resulted in a ratio crossing the widely used cost-effectiveness thresholds of 20, 000 US dollars, 50,000 US dollars, and 100,000 US dollars/QALY or LY. RESULTS: The mean ratios were 69,100 US dollars/LY and 103,100 US dollars/QALY, with corresponding medians of 24,600 US dollars/LY and 20,400 US dollars/QALY. The mean difference between ratios was approximately -34,300 US dollars (median difference: 1300 US dollars), with 60% of ratio pairs differing by 10,000 US dollars/year or less. Mean difference between reciprocals was 59 (QA)LYs per million dollars (median: 2.1). The Spearman rank-order correlation between ratio types was 0.86 (p<0.001). Quality-adjustment led to a ratio moving either above or below 50,000 US dollars/LY (or QALY) in 8% of ratio pairs, and across 100,000 US dollars in 6% of cases. CONCLUSIONS: In a sizable fraction of cost-utility analyses, quality adjusting did not substantially alter the estimated cost-effectiveness of an intervention, suggesting that sensitivity analyses using ad hoc adjustments or 'off-the-shelf' utility weights may be sufficient for many analyses. The collection of preference weight data should be subjected to the same scrutiny as other data inputs to cost-effectiveness analyses, and should only be under-taken if the value of this information is likely to be greater than the cost of obtaining it.  相似文献   
94.
The increasing size, growth, and complexity of the health care industry would appear to offer ample opportunity for innovation and entrepreneurship. But is entrepreneurship really on the rise in health care? We performed a sequential cross-sectional analysis of new, rapidly growing health care businesses in the Inc. 500 list to answer this question. We found that, while there appears to be increasing numbers of opportunities for new, privately held businesses, this varies widely by category. In particular, health information management appeared to be an example of emerging industry, characterized by increases in the number of businesses, as well as in the rate of growth and the average revenue. In contrast, the insurance industry seems to have transitioned to maturity. This article argues that companies that introduce disruptive innovations into health care, either through information technology, new ancillary services, or more focused services to the elderly, will likely be good areas for investors who follow the health care industry as well as entrepreneurs who are looking for a niche for market entry.  相似文献   
95.
96.
Orbital apex syndrome secondary to mucormycosis in immuno-compromised patients is well described; however, few reports exist of a paranasal sinus mycetoma resulting in this presentation in the immuno-competent patient. The case is reported of a 92-year-old man who developed orbital apex syndrome secondary to a sphenoidal sinus mycetoma of Pseudallescheria boydii.  相似文献   
97.
While planning the GAIN International Study of gavestinel in acute stroke, a sequential triangular test was proposed but not implemented. Before the trial commenced it was agreed to evaluate the sequential design retrospectively to evaluate the differences in the resulting analyses, trial durations and sample sizes in order to assess the potential of sequential procedures for future stroke trials. This paper presents four sequential reconstructions of the GAIN study made under various scenarios. For the data as observed, the sequential design would have reduced the trial sample size by 234 patients and shortened its duration by 3 or 4 months. Had the study not achieved a recruitment rate that far exceeded expectation, the advantages of the sequential design would have been much greater. Sequential designs appear to be an attractive option for trials in stroke.  相似文献   
98.
PURPOSE: To determine the effect of surrounding tissue type on coagulation necrosis from radiofrequency (RF) ablation in a homogeneous animal tumor model. MATERIALS AND METHODS: Thirty canine venereal sarcomas were implanted in three tissue sites (subcutaneous, kidney, and lung) in 13 mildly immunosuppressed dogs. Five of 25 tumors, which were 19 mm +/- 3 (mean +/- SD) in diameter, were allocated to each of five groups: (a) subcutaneous tumors, (b) kidney tumors, (c) lung tumors with blood flow, and (d) subcutaneous and (e) renal tumors without blood flow, which was achieved by sacrificing the animal to eliminate tumor perfusion. A sixth group comprised larger subcutaneous tumors (mean diameter, 46 mm +/- 4) that were also treated. RF ablation was performed with a 1-cm tip and 5 minutes of ablation at 90 degrees C +/- 1. Impedance, temperature, and resultant coagulation diameter were recorded and compared. Data were analyzed statistically, including one-way analysis of variance to determine the effect of tissue conductivity (ie, systemic impedance) on necrosis size and tissue temperatures. Linear regression analysis was used to compare changes in impedance between the control and experimental groups. RESULTS: Increasing linear correlation was observed between tumor coagulation diameter and overall baseline system impedance (R(2) = 0.65). RF ablation of lung tumors resulted in the greatest coagulation diameter (13.0 mm +/- 3.5) compared with that in the other groups (P <.01). The smallest coagulation diameter was observed in kidney tumors in the presence of blood flow (7.3 mm +/- 0.6) compared with that in the other groups (P <.01). Elimination of blood flow in kidney tumors increased coagulation diameter to 10.3 mm +/- 0.6 (P <.01). After RF ablation, coagulation diameter in the subcutaneous tumor groups was the same (mean, 9.8 mm +/- 1.0) (difference not significant), regardless of tumor size or presence of blood flow. CONCLUSION: The characteristics of tissue that surrounds tumor, including vascularity and electric conductivity, affect ablation outcome. Predominance of tissue-specific characteristics will likely result in site-specific differences in RF-induced coagulation necrosis.  相似文献   
99.
In this study, the effects of two metals, copper and cadmium, on the growth and development of juvenile Lumbricus rubellus were measured in a toxicity test in which individuals were grown in isolation. This design had a number of advantages over traditional test systems for earthworms. Importantly, the test is specifically designed to measure two juvenile traits (survival over and length of the juvenile period) that have been shown to have a high sensitivity for determining population growth rate. The test system also maximizes replication, while allowing time-series-based monitoring of individual growth. For both metals, significant exposure-dependent effects on survival, growth, development time, and (less certainly) maturation weight were observed. Comparisons of the relative toxicity of the two metals indicated different concentration-response relationships. For copper, hormesis was found at low levels, while only at the highest soil concentration tested (10.07 micromol g(-1)) were (severe) toxic effects present. For cadmium, hormesis was also evident at the lowest concentration tested; however, at soil levels above this, a graded concentration-dependent toxic effect was apparent. These differences in the exposure response patterns can be (tentatively) explained in terms of the mechanisms for handling copper (an essential metal for earthworms) and cadmium (a putative nonessential element). The applicability of the test for routine measurement of chemical effects on ecologically relevant juvenile traits is also outlined and future developments are discussed.  相似文献   
100.
In many genetic linkage analyses, the P value is obtained through simulation since the underlying distribution of the test statistic is complex and unknown. However, this can be very computationally intensive. A "bootstrap/replicate pool" approach has been suggested that generates P values more efficiently in terms of computation by resampling sums from a small set of simulated replicates for each pedigree. The replicate pool idea has been successfully applied, but, to our knowledge, has never been theoretically studied. An entirely different method for increasing the computational efficiency of P value simulation is Besag and Clifford's sequential sampling method. We propose an algorithm which combines Besag and Clifford's method with the replicate pool method to efficiently estimate P values for linkage studies. We derive variance expressions for the P value estimates from the replicate pool method and from our proposed hybrid method, and use these to show that the hybrid estimator has a substantial advantage over the other methods in most situations.  相似文献   
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