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1.
In the present study we comparatively evaluated the first- and second-generation Digene Hybrid Capture assays for detection of human papillomaviruses (HPV) associated with high or intermediate risk for cervical cancer in cervical specimens. Concordant results were obtained with 468 of 483 (96.8%) specimens. All 15 specimens which gave repeatedly discordant results were positive by the second-generation test only, and 14 of them tested PCR positive. The enhanced sensitivity of the second-generation assay is mainly a result of the reformulation of hybridization reagents and, to a lesser extent, a result of the addition of new HPV probes.  相似文献   
2.
This long-term prospective study evaluates the clinical results of subsequent laminectomy in 103 consecutive patients who initially underwent chemonucleolysis (CNL) or laminectomy for lumbar disc herniation. Between 1981 and 1994, 53 patients who had received CNL initially and then underwent laminectomy and 50 patients treated initially with laminectomy underwent a repeat laminectomy. Clinical assessment at 6 weeks showed a success rate of 80.8% for post-CNL laminectomy and 78% for repeat laminectomy. At 6 months, the success rate for patients treated with CNL was 86% versus 78.7% for laminectomy. At 12 months, the overall success rate for the CNL group was 80.4% versus 83.3% for the laminectomy group, but in patients who had not obtained relief from the first procedure the success rate for the second procedure was higher for the post-CNL patients. A questionnaire was sent to all patients for 1- to 13-year follow-up review. The average follow-up period was 6.6 years for post-CNL laminectomy and 5.2 years for repeat laminectomy. The long-term success rate (81.8%) was higher in the post-CNL group compared to 64.4% in the repeat laminectomy group. Seven patients in the post-CNL group and nine in the repeat laminectomy group had undergone a third operation. When these originally successfully treated patients were reassigned after unsuccessful outcomes, the success rate for the CNL groups was 72.7%, versus 51.1% in the laminectomy group (p = 0.049). Employment rates were 80% for patients with CNL (21.8% changed jobs) and 76.3% for patients undergoing laminectomy (48.3% changed jobs) (p = 0.036). In conclusion, patients who underwent laminectomies after receiving CNL had significantly better long-term results than those who had repeat laminectomies.  相似文献   
3.
Clustering is an underspecified task: there are no universal criteria for what makes a good clustering. This is especially true for relational data, where similarity can be based on the features of individuals, the relationships between them, or a mix of both. Existing methods for relational clustering have strong and often implicit biases in this respect. In this paper, we introduce a novel dissimilarity measure for relational data. It is the first approach to incorporate a wide variety of types of similarity, including similarity of attributes, similarity of relational context, and proximity in a hypergraph. We experimentally evaluate the proposed dissimilarity measure on both clustering and classification tasks using data sets of very different types. Considering the quality of the obtained clustering, the experiments demonstrate that (a) using this dissimilarity in standard clustering methods consistently gives good results, whereas other measures work well only on data sets that match their bias; and (b) on most data sets, the novel dissimilarity outperforms even the best among the existing ones. On the classification tasks, the proposed method outperforms the competitors on the majority of data sets, often by a large margin. Moreover, we show that learning the appropriate bias in an unsupervised way is a very challenging task, and that the existing methods offer a marginal gain compared to the proposed similarity method, and can even hurt performance. Finally, we show that the asymptotic complexity of the proposed dissimilarity measure is similar to the existing state-of-the-art approaches. The results confirm that the proposed dissimilarity measure is indeed versatile enough to capture relevant information, regardless of whether that comes from the attributes of vertices, their proximity, or connectedness of vertices, even without parameter tuning.  相似文献   
4.
Ceramic hydroxyapatite is frequently used in clinical practice nowadays; it is applied in surgical interventions on facial skull bones. This biological material is used as bone substitute and bone connector, but many authors claim that it is devoid of osteoinductor properties. Research is in progress on the effects of a "cold", that is, biochemically active form of ceramic hydroxyapatite on proliferative activity of a number of cell populations. No mitogenesis stimulation was observed during incubation of hydroxyapatite with osteoblast culture; on the contrary, a reduction of proliferative processes intensity was observed. Remembering that hydroxyapatite is a surfactant we repeated this experiment under similar conditions but used a hydroxyapatite molbfication with specific activity increased by two orders in comparison with its close analogs. Mitogenesis intensity was assessed by radiometric method from 3H-thymidine incorporation. The data indicated stimulation of proliferative processes in osteoblast culture.  相似文献   
5.
The 2D hexagonal mesh, based on triangle plane tessellation, is considered as a multiprocessor interconnection network. The 3D hexagonal mesh is presented as a natural extension of the hexagonal mesh. Although the topological properties of the 2D hexagonal mesh are well known, existing addressing schemes are not suitable to be extended to 3D hexagonal mesh. Then, we present, in this paper, a new addressing scheme and an optimal routing algorithm for 2D hexagonal network based on the distance formula and using shortest paths. We propose also a 3D hexagonal network that can be built with 2D hexagonal meshes as a natural generalization. We also present some topological properties, an efficient addressing scheme, and an optimal routing algorithm based on our 2D routing algorithm.  相似文献   
6.
This paper deals with a dual-axis sun tracking system for a photovoltaic system. Its trajectories are determined by an optimization procedure. The optimization goal is the maximization of the electrical energy production within a photovoltaic system, by considering the tracking system consumption. The procedure used for determining the tilt angle and azimuth angle trajectories is described as a nonlinear and bounded optimization problem. Since an explicit form of the objective function is unavailable, a stochastic search algorithm called Differential Evolution is applied as the optimization tool. In order to evaluate the objective function, models for calculating the available solar radiation and tracking system consumption are applied together with the efficiencies of solar cells, a DC/DC converter and inverter. A new algorithm is introduced for the time dependent prediction of available solar radiation. It is based on the length of a sunbeam’s path through the atmosphere and the statistical data of a pyranometer measured total and diffuse solar radiation at a given location on the Earth. The optimization bounds are given in the form of angular speed, lower and upper bounds for both angles and angle quantization. The results presented in this paper show, that the optimal trajectories can help to increase the electrical energy production within photovoltaic systems by sun tracking.  相似文献   
7.
During the past decade, molecular methods based on the detection of viral DNA have become a key tool for the detection of human papillomaviruses (HPVs) in tissue. The methods can be divided into two groups: those in which tissue destruction is unavoidable for the detection of HPV DNA, and those in which the detection of viral DNA is performed in a way that allows tissue morphology preservation. Polymerase chain reaction is currently the most sensitive method for HPV detection and an excellent research tool. However, because of frequent contamination problems and lack of standardization, it is not readily applicable to diagnostic laboratories. The recent improvements in in situ hybridization have made it possible for this method to become the most appropriate method for routine detection of HPVs in tissue. At present, however, the use of at least two independent HPV DNA detection methods is indispensable for accurate determination of HPVs.  相似文献   
8.
Chiral 1,2‐diamines are privileged structural motifs in organocatalysis, whereas efficient 1,3‐diamine‐derived organocatalysts are very rare. Herein we report a highly efficient camphor‐1,3‐diamine‐derived squaramide organocatalyst. Its catalytic activity in Michael additions of 1,3‐dicarbonyl nucleophiles to trans‐β‐nitrostyrene derivatives provides excellent enantioselectivities (up to >99% ee).

  相似文献   

9.
Different methods for voltage sag source detection are discussed. They are based either on disturbance energy, voltage-current characteristic or active (real) current component. It is shown that, in the cases of asymmetrical voltage sags, both current-based methods known from literature do not work well. These two methods are therefore generalised using a vector-space approach. Furthermore, three new methods are introduced using orthogonal Clarke's transformation, which can be used to detect the sources of those voltage sags provoked by earth faults. All the discussed methods for voltage sag source detection have been tested by applying extensive simulations, laboratory tests and field testing. The results obtained show the very high effectiveness of the proposed methods, which are superior to the methods known from literature, especially for detecting sources of asymmetrical voltage sags.  相似文献   
10.
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