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Malacoplakia of the prostate and seminal vesicle. Ultrastructural study and review of the literature
M Sánchez Chapado J Angulo Cuesta M Guil Cid R Lera Fernández A Dehaini L Prieto Chaparro 《Canadian Metallurgical Quarterly》1995,48(8):775-778
OBJECTIVES: The present study describes a case of malacoplakia of the genitourinary tract arising in the seminal vesicle and prostate and reviews similar cases previously reported in the literature. METHOD: A 67-year-old male consulted for hemospermia and voiding symptoms. Prostatic neoplasm was suspected on the basis of the clinical and radiological findings. RESULTS: The diagnosis was made only after biopsy and histological analysis. Electron microscopy is a very useful tool. Long-term antibiotic therapy may achieve optimal results. Treatment with fluoroquinolones was successful. CONCLUSION: To avoid unwarranted radical approaches, we underscore the possibility that prostatic pseudotumors may be misinterpreted as neoplasia. Malacoplakia is diagnosed only by histology and requires medical treatment. 相似文献
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Jorge Larrey-Ruiz Rafael Verdú-MonederoJuan Morales-Sánchez Jesús Angulo 《Image and vision computing》2011,29(9):620-630
The present work is intended to address two of the major difficulties that can be found when tackling the estimation of the local orientation of the data in a scene, a task which is usually accomplished by means of the computation of the structure tensor-based directional field. On one hand, the orientation information only exists in the non-homogeneous regions of the dataset, while it is zero in the areas where the gradient (i.e. the first-order intensity variation) remains constant. Due to this lack of information, there are many cases in which the overall shape of the represented objects cannot be precisely inferred from the directional field. On the other hand, the orientation estimation is highly dependent on the particular choice of the averaging window used for its computation (since a collection of neighboring gradient vectors is needed to obtain a dominant orientation), typically resulting in vector fields which vary from very irregular (thus yielding a noisy estimation) to very uniform (but at the expense of a loss of angular resolution). The proposed solution to both drawbacks is the regularization of the directional field; this process extends smoothly the previously computed vectors to the whole dataset while preserving the angular information of relevant structures. With this purpose, the paper introduces a suitable mathematical framework and deals with the d-dimensional variational formulation which is derived from it. The proposed formulation is finally translated into the frequency domain in order to obtain an increase of insight on the regularization problem, which can be understood as a low-pass filtering of the directional field. The frequency domain point of view also allows for an efficient implementation of the resulting iterative algorithm. Simulation experiments involving datasets of different dimensionality prove the validity of the theoretical approach. 相似文献
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Xavier Perez-Sala Laura Igual Sergio Escalera Cecilio Angulo 《International Journal of Computer Vision》2017,121(3):327-343
Procrustes analysis (PA) has been a popular technique to align and build 2-D statistical models of shapes. Given a set of 2-D shapes PA is applied to remove rigid transformations. Later, a non-rigid 2-D model is computed by modeling the residual (e.g., PCA). Although PA has been widely used, it has several limitations for modeling 2-D shapes: occluded landmarks and missing data can result in local minima solutions, and there is no guarantee that the 2-D shapes provide a uniform sampling of the 3-D space of rotations for the object. To address previous issues, this paper proposes subspace PA (SPA). Given several instances of a 3-D object, SPA computes the mean and a 2-D subspace that can model rigid and non-rigid deformations of the 3-D object. We propose a discrete (DSPA) and continuous (CSPA) formulation for SPA, assuming that 3-D samples of an object are provided. DSPA extends the traditional PA, and produces unbiased 2-D models by uniformly sampling different views of the 3-D object. CSPA provides a continuous approach to uniformly sample the space of 3-D rotations, being more efficient in space and time. We illustrate the benefits of SPA in two different applications. First, SPA is used to learn 2-D face and body models from 3-D datasets. Experiments on the FaceWarehouse and CMU motion capture (MoCap) datasets show the benefits of our 2-D models against the state-of-the-art PA approaches and conventional 3-D models. Second, SPA learns an unbiased 2-D model from CMU MoCap dataset and it is used to estimate the human pose on the Leeds Sports dataset. 相似文献
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Foodborne diseases are an important public problem affecting millions of Americans each year and resulting in substantial morbidity and mortality. Many foodborne infections occur in outbreak settings. Outbreaks are often detected by complaints from the public to health authorities. This report reviews complaints received by the San Francisco Department of Public Health involving suspected foodborne illness in 1998. Although such foodborne complaints are commonly received by health officials, we provide the first review of population-based data describing such complaints. We use a broad definition of a foodborne disease outbreak. We judged a complaint to be a "likely foodborne disease outbreak" if it involved more than one person and more than one family; no other common meals were shared recently by ill persons; diarrhea, vomiting, or both was reported; and the incubation period was more than one hour. In 1998, 326 complaints of foodborne illness, involving a total of 599 ill people, were received by the Communicable Disease Control Unit in San Francisco. The complaints involved from 1 to 36 ill persons, with 61% involving one ill person and 25% involving two ill persons. Of the 126 reports involving illness in more than one person, 77 (61%) were judged to be likely foodborne disease outbreaks. Three of these 77 outbreaks had been investigated prior to our review. This project confirms that more foodborne disease outbreaks occur than are reported to state and national outbreak surveillance systems. Our review of the San Francisco system highlights opportunities for gleaning valuable information from the foodborne disease complaint systems in place in most jurisdictions. 相似文献
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Most industrialised countries are currently drawing up their procedures to deal with contaminated land. In the Basque Country generic soil quality values applicable to different land uses have been drawn up for many common soil inorganic and organic pollutants, to assist in the site assessment process. In this paper we present those values aimed at protecting ecosystems as the main target at risk. Ecological risk was defined on the basis of effects on the structure of the soil invertebrate community. Ecotoxicological data from laboratory tests were used in combination with a theoretical extrapolation method. The following groups of compounds were assayed: heavy metals, cyanides, aromatic compounds, polycyclic aromatic hydrocarbons, HCH isomers, chlorinated organic compounds, and mineral oil. A specific toxicity database was created. The reliability of the values obtained as well as the limitations of the derivation process are discussed. 相似文献
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H. Khodja M. Hanot M. Carrière J. Hoarau J.F. Angulo 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(12-13):1999-2002
Low dose and non-targeted effect studies continue to attract the attention of a growing number of radiobiologists. Experimental setups based on light ion microbeams constitute a tool of choice for this kind of investigations. However, a careful attention must be given to experimental conditions, as setup-induced stress levels should be well below those induced by the irradiation itself. Here, we present the current status of the single-particle microbeam facility that has been developed these last years at the nuclear microprobe of Saclay. The driving idea was to build a facility in which local irradiation studies are performed in an environment close to cellular biology standards. This facility includes unique features, such as (i) a compact setup that allows easy access and vertical irradiation mode, (ii) a collimated beam that can be mechanically positioned under the desired cells at a very fast speed, avoiding the requirement of a focusing element and (iii) a controlled environment (temperature, CO2, humidity) that allows performing of very long term experiments on cultured cells.Fluorescent techniques are implemented and permit in situ monitoring of cellular responses to irradiations.Several radiobiological studies are already underway and this will be illustrated with recent results regarding DNA damage and reactive oxygen species signaling time courses following targeted irradiations. 相似文献
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Wallace DJ Van Gilder T Shallow S Fiorentino T Segler SD Smith KE Shiferaw B Etzel R Garthright WE Angulo FJ 《Journal of food protection》2000,63(6):807-809
In 1997, the Foodborne Diseases Active Surveillance Program (FoodNet) conducted active surveillance for culture-confirmed cases of Campylobacter, Escherichia coli O157, Listeria, Salmonella, Shigella, Vibrio, Yersinia, Cyclospora, and Cryptosporidium in five Emerging Infections Program sites. FoodNet is a collaborative effort of the Centers for Disease Control and Prevention's National Center for Infectious Diseases, the United States Department of Agriculture's Food Safety and Inspection Service, the Food and Drug Administration's Center for Food Safety and Applied Nutrition, and state health departments in California, Connecticut, Georgia, Minnesota, and Oregon. The population under active surveillance for foodborne infections was approximately 16.1 million persons or roughly 6% of the United States Population. Through weekly or monthly contact with all clinical laboratories in these sites, 8,576 total isolations were recorded: 2,205 cases of salmonellosis, 1,273 cases of shigellosis, 468 cases of cryptosporidiosis, 340 of E. coli O157:H7 infections, 139 of yersiniosis, 77 of listeriosis, 51 of Vibrio infections, and 49 of cyclosporiasis. Results from 1997 demonstrate that while there are regional and seasonal differences in reported incidence rates of certain bacterial and parasitic diseases, and that some pathogens showed a change in incidence from 1996, the overall incidence of illness caused by pathogens under surveillance was stable. More data over more years are needed to assess if observed variations in incidence reflect yearly fluctuations or true changes in the burden of foodborne illness. 相似文献