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991.
Scheidegger C Vo H Koop D Freire J Silva C 《IEEE transactions on visualization and computer graphics》2007,13(6):1560-1567
While there have been advances in visualization systems, particularly in multi-view visualizations and visual exploration, the process of building visualizations remains a major bottleneck in data exploration. We show that provenance metadata collected during the creation of pipelines can be reused to suggest similar content in related visualizations and guide semi-automated changes. We introduce the idea of query-by-example in the context of an ensemble of visualizations, and the use of analogies as first-class operations in a system to guide scalable interactions. We describe an implementation of these techniques in VisTrails, a publicly-available, open-source system. 相似文献
992.
Zhen EY Berna MJ Jin Z Pritt ML Watson DE Ackermann BL Hale JE 《Proteomics. Clinical applications》2007,1(7):661-671
Heart fatty acid binding protein (Fabp3) is a cytosolic protein expressed primarily in heart, and to a lesser extent in skeletal muscle, brain, and kidney. During myocardial injury, the Fabp3 level in serum is elevated rapidly, making it an ideal early marker for myocardial infarction. In this study, an MS‐based selected reaction monitoring method (LC‐SRM) was developed for quantifying Fabp3 in rat serum. Fabp3 was enriched first through an immobilized antibody, and the protein was digested on beads directly. A marker peptide of Fabp3 was quantified using LC‐SRM with a stable isotope‐labeled peptide standard. For six quality control samples with Fabp3 ranging from 0.256 to 25 ng, the average recovery following the procedure was about 73%, and the precision (%CV) between replicates was less than 7%. The Fabp3 concentrations in rat serum peaked 1 h after isoproterenol treatment, and returned to baseline levels 24 h after the dose. Elevated Fabp3 levels were also detected in rats administered with a PPAR α/δ agonist, which has shown to cause skeletal muscle necrosis. Fabp3 can be used as a biomarker for both cardiac and skeletal necroses. The cross‐validation of the LC‐SRM method with an existing ELISA method is described. 相似文献
993.
Anna Korzynska Wojciech Strojny Andreas Hoppe David Wertheim Pawel Hoser 《Pattern Analysis & Applications》2007,10(4):301-319
This paper describes a segmentation method combining a texture based technique with a contour based method. The technique
is designed to enable the study of cell behaviour over time by segmenting brightfield microscope image sequences. The technique
was tested on artificial images, based on images of living cells and on real sequences acquired from microscope observations
of neutrophils and lymphocytes as well as on a sequence of MRI images. The results of the segmentation are compared with the
results of the watershed and snake segmentation methods. The results show that the method is both effective and practical.
相似文献
Anna KorzynskaEmail: |
994.
One of the cornerstones of expert performance in complex domains is the ability to perceive problem situations in terms of
their task-relevant semantic properties. One such class of properties consists of phenomena that are defined in terms of patterns
of change over time, i.e., events. A basic pre-requisite for working towards tools to support event recognition is a method for understanding the events that
expert practitioners find meaningful in a given field of practice. In this article we present the modified unit marking procedure
(mUMP), a technique adapted from work on social perception to facilitate identification of the meaningful phenomena which
observers attend to in a dynamic data array. The mUMP and associated data analysis techniques are presented with examples
from a first of a kind study where they were used to elicit and understand the events practitioners found meaningful in a
scenario from an actual complex work domain.
相似文献
David D. WoodsEmail: |
995.
We describe a decision support system to distinguish among hematology cases directly from microscopic specimens. The system
uses an image database containing digitized specimens from normal and four different hematologic malignancies. Initially,
the nuclei and cytoplasmic components of the specimens are segmented using a robust color gradient vector flow active contour
model. Using a few cell images from each class, the basic texture elements (textons) for the nuclei and cytoplasm are learned,
and the cells are represented through texton histograms. We propose to use support vector machines on the texton histogram
based cell representation and achieve major improvement over the commonly used classification methods in texture research.
Experiments with 3,691 cell images from 105 patients which originated from four different hospitals indicate more than 84%
classification performance for individual cells and 89% for case based classification for the five class problem.
相似文献
Oncel TuzelEmail: |
996.
Braunschweig T Kaserer K Chung JY Bilke S Krizman D Knezevic V Hewitt SM 《Proteomics. Clinical applications》2007,1(3):264-271
Thyroid cancer is the most common endocrine neoplasm with multiple histologic subtypes, each associated with different treatments and outcomes. Differentiating benign neoplasms such as follicular adenomas from malignant entities such as follicular carcinomas and papillary carcinoma can be challenging. To define the proteomic profile of different thyroid tumors, we screened an antibody array of 330 features against five thyroid neoplasms: follicular adenoma, follicular carcinoma, papillary carcinoma, anaplastic carcinoma, and medullary carcinoma as well as normal thyroid epithelium. Eight candidate biomarkers; c-erbB-2, Stat5a, Annexin IV, IL-11, RARα, FGF7, Caspase 9, and phospho-c-myc were identified as differentially expressed on the antibody array, and validated with immunohistochemistry on tissue microarrays, with a total of 144 samples of the same variety of thyroid neoplasms. Analysis revealed c-erbB-2, Annexin IV, and Stat5a have potential clinical utility to differentiate follicular adenoma, follicular carcinoma, and papillary carcinoma from each other. By using an antibody array as a discovery platform and a tissue microarray as a first step in validation on a large number of specimens, we have identified new markers that have potential utility in the diagnosis of thyroid neoplasms. 相似文献
997.
Fentz AK Spörl M Spangenberg J List HJ Zornig C Dörner A Layer P Juhl H David KA 《Proteomics. Clinical applications》2007,1(6):536-544
Colorectal cancer is the second leading cause of cancer death, and it develops from benign colorectal adenomas in over 95% of patients. Early detection of these cancer precursors by screening tests and their removal can potentially eradicate more than 95% of colorectal cancers before they develop. To discover sensitive and specific biomarkers for improvement of pre‐clinical diagnosis of colorectal adenoma and cancer, we analysed in two independent studies (n = 87 and n = 83 patients) serum samples from colorectal cancer (stage III), colorectal adenoma and control patients using SELDI‐TOF‐MS. Extensive statistical analysis was performed to establish homogeneous patient groups based on their clinical data. Two biomarkers that were each able to distinguish control patients from either colorectal adenoma or colorectal cancer patients (p<0.001) were identified as transthyretin (pre‐albumin) and C3a‐desArg by MS/MS and were further validated by antibody‐based assays (radial immunodiffusion, ELISA). A combination of both proteins clearly indicated the presence of colorectal adenoma or carcinoma. Using a cut‐off of <0.225 g/L for transthyretin and >1974 ng/mL for C3a‐desArg, we found a sensitivity and specificity for colorectal adenoma of 96% and 70%, respectively. 相似文献
998.
Random multispace quantization as an analytic mechanism for BioHashing of biometric and random identity inputs 总被引:2,自引:0,他引:2
Teoh AB Goh A Ngo DC 《IEEE transactions on pattern analysis and machine intelligence》2006,28(12):1892-1901
Biometric analysis for identity verification is becoming a widespread reality. Such implementations necessitate large-scale capture and storage of biometric data, which raises serious issues in terms of data privacy and (if such data is compromised) identity theft. These problems stem from the essential permanence of biometric data, which (unlike secret passwords or physical tokens) cannot be refreshed or reissued if compromised. Our previously presented biometric-hash framework prescribes the integration of external (password or token-derived) randomness with user-specific biometrics, resulting in bitstring outputs with security characteristics (i.e., noninvertibility) comparable to cryptographic ciphers or hashes. The resultant BioHashes are hence cancellable, i.e., straightforwardly revoked and reissued (via refreshed password or reissued token) if compromised. BioHashing furthermore enhances recognition effectiveness, which is explained in this paper as arising from the random multispace quantization (RMQ) of biometric and external random inputs 相似文献
999.
Robust regression for high throughput drug screening 总被引:1,自引:0,他引:1
Effective analysis of high throughput screening (HTS) data requires automation of dose-response curve fitting for large numbers of datasets. Datasets with outliers are not handled well by standard non-linear least squares methods, and manual outlier removal after visual inspection is tedious and potentially biased. We propose robust non-linear regression via M-estimation as a statistical technique for automated implementation. The approach of finding M-estimates by Iteratively Reweighted Least Squares (IRLS) and the resulting optimization problem are described. Initial parameter estimates for iterative methods are important, so self-starting methods for our model are presented. We outline the software implementation, done in Matlab and deployed as an Excel application via the Matlab Excel Builder Toolkit. Results of M-estimation are compared with least squares estimates before and after manual editing. 相似文献
1000.
Slightly modified versions of an early Hebbian/anti-Hebbian neural network are shown to be capable of extracting the sparse, independent linear components of a prefiltered natural image set. An explanation for this capability in terms of a coupling between two hypothetical networks is presented. The simple networks presented here provide alternative, biologically plausible mechanisms for sparse, factorial coding in early primate vision. 相似文献