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排序方式: 共有567条查询结果,搜索用时 734 毫秒
71.
Stelling A Salzer R Kirsch M Sobottka SB Geiger K Koch E Schackert G Steiner G 《Analytical and bioanalytical chemistry》2011,400(9):2745-2753
Established methods for characterization of tissue and diagnostics, for example histochemistry, magnetic resonance imaging
(MRI), X-ray tomography, or positron emission tomography (PET), are mostly not suitable for intra-operative use. However,
there is a clear need for an intra-operative diagnostics especially to identify the borderline between normal and tumor tissue.
Currently, vibrational spectroscopy techniques (both Raman and infrared) complement the standard methods for tissue diagnostics.
Vibrational spectroscopy has the potential for intra-operative use, because it can provide a biochemically based profile of
tissue in real time and without requiring additional contrast agents, which may perturb the tissue under investigation. In
addition, no electric potential needs to be applied, and the measurements are not affected by electromagnetic fields. Currently,
promising approaches include Raman fiber techniques and nonlinear Raman spectroscopy. Infrared spectroscopy is also being
used to examine freshly resected tissue ex vivo in the operating theater. The immense volume of information contained in Raman
and infrared spectra requires multivariate analysis to extract relevant information to distinguish different types of tissue.
The promise and limitations of vibrational spectroscopy methods as intra-operative tools are surveyed in this review. 相似文献
72.
Walther J Gaertner M Cimalla P Burkhardt A Kirsten L Meissner S Koch E 《Analytical and bioanalytical chemistry》2011,400(9):2721-2743
Optical coherence tomography (OCT) is a noninvasive, high-resolution, interferometric imaging modality using near-infrared
light to acquire cross-sections and three-dimensional images of the subsurface microstructure of biological specimens. Because
of rapid improvement of the acquisition speed and axial resolution of OCT over recent years, OCT is becoming increasingly
attractive for applications in biomedical research. Therefore, OCT is no longer used solely for structural investigations
of biological samples but also for functional examination, making it potentially useful in bioanalytical science. The combination
of in vivo structural and functional findings makes it possible to obtain thorough knowledge on basic physiological and pathological
processes. Advanced applications, for example, optical biopsy in visceral cavities, have been enabled by combining OCT with
established imaging modalities. This report gives an outline of the state of the art and novel trends of innovative OCT approaches
in biomedical research in which the main focus is on applications in fundamental research and pre-clinical utilization. 相似文献
73.
Edmund R. Puczy?owski 《Journal of Pure and Applied Algebra》2011,215(7):1596-1605
We describe modular lattices with 0 for which a counterpart of the property that minimal generating subsets of linear spaces are their bases is satisfied and those for which cardinalities of minimal generating sets are equal to the Goldie dimension. The results obtained on lattices are applied to modules. 相似文献
74.
We present a model for the surgery admission planning problem, and a meta-heuristic algorithm for solving it. The problem
involves assigning operating rooms and dates to a set of elective surgeries, as well as scheduling the surgeries of each day
and room. Simultaneously, a schedule is created for each surgeon to avoid double bookings. The presented algorithm uses simple
Relocate and Two-Exchange neighbourhoods, governed by an iterated local search framework. The problem’s search space associated
with these move operators is analysed for three typical fitness surfaces, representing different compromises between patient
waiting time, surgeon overtime, and waiting time for children in the morning on the day of surgery. The analysis shows that
for the same problem instances, the different objectives give fitness surfaces with quite different characteristics. We present
computational results for a set of benchmarks that are based on the admission planning problem in a chosen Norwegian hospital. 相似文献
75.
Edmund J. Copeland Andrew R. Liddle James E. Lidsey David Wands 《General Relativity and Gravitation》1998,30(12):1711-1715
Two strands of observational gravitation, one the search for astrophysical evidence of primordial black holes and the other the search for gravitational waves, may combine to provide strong evidence in favour of cosmological models based on superstring theory, the leading candidate for unifying gravity with the other fundamental forces. 相似文献
76.
Designing tree-structured organizations for computational agents 总被引:4,自引:0,他引:4
We describe a framework for defining the space of organization designs for computational agents, use our framework for analyzing the expected performance of a class of organizations, and describe how our analyses can be applied to predict performance for a distributed information gathering task. Our analysis specifically addresses the impact of the span of control (branching factor) in tree-structured hierarchical organizations on the response time of such organizations. We show quantitatively how the overall task size and granularity influence the design of the span of control for the organization, and that within the class of organizations considered the apropriate span of control is confined to a relatively narrow range. The performance predicted by our overall model correlates with the actual performance of a distributed organization for computer network monitoring. Consequently, we argue that our framework can support aspects of organizational self-design for computational agents, and might supply insights into the design of human organizations as well. 相似文献
77.
Edmund Landau 《Mathematische Zeitschrift》1929,30(1):205-207
Ohne Zusammenfassung 相似文献
78.
Edmund Weis 《Monatshefte für Chemie / Chemical Monthly》1904,25(9):1065-1072
Ohne ZusammenfassungZum Schlusse sei es mir gestattet, Herrn Hofrat Lieben für die freundliche Unterstützung bei dieser Arbeit aufs wärmste zu danken. 相似文献
79.
80.