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排序方式: 共有209条查询结果,搜索用时 15 毫秒
1.
STUDY OBJECTIVE: To evaluate insurance status and frequency of use of emergency services in adults with sickle cell disease. DESIGN: Retrospective analysis of visits. SETTING: Emergency department and outpatient clinics of an urban university hospital. PARTICIPANTS: One hundred seventy-two subjects, who made 771 visits to the ED during 1990. RESULTS: Of the 172 subjects, 31 were covered by commercial insurance, 32 were covered by Medicare, and 109 were covered by Medicaid or were uninsured. Insurance status and frequency of use of emergency services were independent (P > .05). On discriminant analysis, Medicaid-covered and uninsured subjects were correctly classified, but commercially insured and Medicare subjects were not. Medicaid and uninsured subjects were more likely to be younger and to live closer to the hospital (P < .00005). High-frequency users of emergency services were discriminated from low-frequency users. High-frequency users were more likely to be younger, to be users of primary-care services, and to live closer to the hospital (P = .0004). CONCLUSION: Provision of primary-care services or stable insurance in the form of commercial insurance or Medicare did not decrease use of emergency services in subjects with sickle cell disease in a group of patients selected from one urban academic ED. 相似文献
2.
The authors report a case of pregnancy in a rudimentary horn diagnosed by laparotomy. The location could not be suspected by any clinical sign. This pregnancy stopped at 19 weeks of amenorrhoea. Any attempts of induction of labour failed. Laparotomy was necessary to assess the diagnosis and to allow the resection of the uterine horn. The authors present a review of literature. 相似文献
3.
Dorn R. Baumgartner A. Goth A. Gutu-Nelle A. Koppenborg J. Rehm W. Schneider R. Schneider S. von Wirth J. Weber D. 《Lightwave Technology, Journal of》1991,9(6):709-714
Mechanically shaped preforms (MSP) have been demonstrated to combine economic non-CVD (chemical vapor deposition) processing and low loss, with a published value of 0.63 dB/km and a size of 30 fkm/preform. Improved processing is proposed which results in a minimum loss of 0.27 dB/km at 1550 nm. Preforms capable of yielding 150 fkm have been produced. Reboiling during preform stretching and fiber pulling is identified as the last remaining problem of the process 相似文献
4.
Differential optical absorption spectroscopy (DOAS) of atmospheric trace gases requires the detection of optical densities below 0.1%. Photodiode arrays are used more and more as detectors for DOAS because they allow one to record larger spectral intervals simultaneously. This type of optical multichannel analyzer (OMA), however, shows sensitivity differences among the individual photodiodes (pixels), which are of the order of 1%. To correct for this a sensitivity reference spectrum is usually recorded separately from the trace-gas measurements. Because of atmospheric turbulence the illumination of the detector while an atmospheric absorption spectrum is being recorded is different from the conditions during the reference measurement. As a result the sensitivity patterns do not exactly match, and the corrected spectra still show a residual structure that is due to the sensitivity difference. This effect usually limits the detection of optical densities to approximately 3 × 10(-4). A new method for the removal of the sensitivity pattern is presented in this paper: Scanning the spectrometer by small wavelength increments after each readout of the OMA allows one to separate the OMA-fixed pattern and the wavelength-fixed structures (absorption lines). The properties of the new method and its applicability are demonstrated with simulated spectra. Finally, first atmospheric measurements with a laser long-path instrument demonstrate a detection limit of 3 × 10(-5) of a DOAS experiment. 相似文献
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6.
Isolde Adler Frederic Dorn Fedor V. Fomin Ignasi Sau Dimitrios M. Thilikos 《Algorithmica》2012,64(1):69-84
Minor Containment is a fundamental problem in Algorithmic Graph Theory used as a subroutine in numerous graph algorithms. A model of a graph H in a graph G is a set of disjoint connected subgraphs of G indexed by the vertices of H, such that if {u,v} is an edge of H, then there is an edge of G between components C u and C v . A graph H is a minor of G if G contains a model of H as a subgraph. We give an algorithm that, given a planar n-vertex graph G and an h-vertex graph H, either finds in time $\mathcal{O}(2^{\mathcal{O}(h)} \cdot n +n^{2}\cdot\log n)$ a model of H in G, or correctly concludes that G does not contain H as a minor. Our algorithm is the first single-exponential algorithm for this problem and improves all previous minor testing algorithms in planar graphs. Our technique is based on a novel approach called partially embedded dynamic programming. 相似文献
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Workflow design, mashup configuration, and composite service formation are examples where the capabilities of multiple simple services combined achieve a complex functionality. In this paper, we address the problem of limiting the number of required services that fulfill the required capabilities while exploiting the functional specialization of individual services. Our approach strikes a balance between finding one service that matches all required capabilities and having one service for each required capability. Specifically, we introduce a weighted fuzzy clustering algorithm that detects implicit service capability groups. The clustering algorithm considers capability importance and service fitness to support those capabilities. Evaluation based on a real-world data set successfully demonstrates the effectiveness of and applicability for service aggregation. 相似文献
9.
Claudio Sedivy Rafal Piskorski Andreas Müller Silvia Dorn 《Journal of chemical ecology》2012,38(8):996-1002
Growing evidence suggests that the freely accessible pollen of some plants is chemically protected against pollen-feeding flower visitors. For example, a diet of pollen from buttercup plants (Ranunculus) recently was shown to have a deleterious effect on developing larvae of several bee species not specialized on Ranunculus. Numerous Ranunculus species contain ranunculin, the glucosyl hydrate form of the highly reactive and toxic lactone protoanemonin, that causes the toxicity of these plants. We tested whether the presence of ranunculin is responsible for the lethal effects of R. acris pollen on the larvae of two bee species that are not Ranunculus specialists. To investigate the effect on bee larval development, we added ranunculin to the pollen provisions of the Campanula specialist bee Chelostoma rapunculi and the Asteraceae specialist bee Heriades truncorum, and allowed the larvae to feed on these provisions. We quantified ranunculin in pollen of R. acris and in brood cell provisions collected by the Ranunculus specialist bee Chelostoma florisomne. We demonstrated that although ranunculin was lethal to both tested bee species in high concentrations, the concentration in the pollen of R. acris was at least fourfold lower than that tolerated by the larvae of C. rapunculi and H. truncorum in the feeding experiments. Ranunculin concentration in the brood cells of C. florisomne was on average even twentyfold lower than that in Ranunculus pollen, suggesting that a mechanism different from ranunculin intoxication accounts for the larval mortality reported for bees not specialized on Ranunculus pollen. 相似文献
10.
Rafael K. de Andrades Márcio Dorn Daniel S. Farenzena Luis C. Lamb 《Expert systems with applications》2013,40(13):5210-5218
The Medical and Pharmaceutical industries have shown high interest in the precise engineering of protein hormones and enzymes that perform existing functions under a wide range of conditions. Proteins are responsible for the execution of different functions in the cell: catalysis in chemical reactions, transport and storage, regulation and recognition control. Computational Protein Design (CPD) investigates the relationship between 3-D structures of proteins and amino acid sequences and looks for all sequences that will fold into such 3-D structure. Many computational methods and algorithms have been proposed over the last years, but the problem still remains a challenge for Mathematicians, Computer Scientists, Bioinformaticians and Structural Biologists. In this article we present a new method for the protein design problem. Clustering techniques and a Dead-End-Elimination algorithm are combined with a SAT problem representation of the CPD problem in order to design the amino acid sequences. The obtained results illustrate the accuracy of the proposed method, suggesting that integrated Artificial Intelligence techniques are useful tools to solve such an intricate problem. 相似文献