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141.
Six rhesus monkeys self-administered orally delivered phencyclidine (PCP; 0.35 mg/ml) with saccharin (0.3 or 0.03 % wt/vol) or water under concurrenl fixed-ralio (FR) schedules. During daily 3-hr sessions, subjects had concurrent access to liquids: PCP versus water, PCP versus saccharin. or saccharin versus water. The FR of both liquids was varied (4, 8, 16, 32, and 64) in nonsystematic order and when behavior was stable at each FR, buprenorphine (0.005 mg/kg) was injected intramuscularly for 5 days. Buprenorphine treatment decreased PCP deliveries by 16–65% across the range of FR values when compared with the no-treatment baseline, and concurrent saccharin reduced PCP deliveries from 34 to 63%. Combining buprenorphine treatment and concurrent availability of saccharin produced decreases in PCP deliveries of 70–87% from the no-trealmenl baseline across the FR values. Greater reductions were found at the highest FR values. Pmax values were shifted to the left under all treatment conditions, suggesting that the reinforcing efficacy of the drug was reduced. These findings suggest that pharmacological and behavioral treatments produce additive reductions in drug self-administration. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
142.
Age differences in depressive symptom experiences were investigated in a community sample of women (N?=?287, aged 55–95 years). The purpose of the analysts was to compare the age-depression relation using 3 different measurement approaches: (a) a standard screening scale, (b) a clinical diagnostic, and (c) a latent variable measurement approach. The analysis, which uses structural equation modeling procedures, extends earlier confirmatory factor analyses of the Symptom Checklist-90—Revised Depression and Additional Symptoms scales conducted by Newmann, Engel, & Jensen (1990, 1991). Findings show that each measurement approach leads to different conclusions about the age-depression relation, with only the latent variable measurement showing a significant increase in depressive symptoms with advancing age. Implications of these findings for future research on aging and depression are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
143.
Background and rationale for a comprehensive model of training for psychologists to provide services to children and adolescents are outlined. Eleven integrated aspects of training are described with respect to training topics, justification for the training, and ways to implement the training. The model described address the need for guidance in training specialists in psychologically based mental health services for children, adolescents, and their families. Practitioners can use this model to assess their own backgrounds, knowledge, and skills in working with these populations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
144.
Today's service-oriented systems realize many ideas from the research conducted a decade or so ago in multiagent systems. Because these two fields are so deeply connected, further advances in multiagent systems could feed into tomorrow's successful service-oriented computing approaches. This article describes a 15-year roadmap for service-oriented multiagent system research.  相似文献   
145.
146.
The president of APA's Division Two suggests that those who teach psychology can make contributions to psychologist-scholars in theoretical and philosophical psychology. She indicates that members of Division Two could use some help in learning to think differently about the psychology they teach and specifically about the ways in which they try to teach theoretical and philosophical issues in psychology. For Division Two's part, she believes that their members could reciprocate with additional insights that might help Division 24's students learn. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
147.
Eight English instructors at Marist College, Poughkeepsie, New York, conducted a one-semester controlled experiment with freshman in eight randomly selected classes of College Writing to learn about the initial effects of word processing on essay-writing performance and on writing apprehension. Four classes wrote essays using terminals linked to a mainframe computer (Experimental Group), and four classes wrote essays in the traditional mode using pens, pencils or typewriters (Control Group). The eight instructors agreed upon a common syllabus and common teaching approaches for the freshman writing course. To measure writing performance, they devised an analytic scale. To measure writing apprehension, they used a writing apprehension test developed by Daly and Miller. The Experimental Group showed greater progress than the Control Group from the pre to post Essay Test but could not demonstrate superior performance on the six required essays of the course. For writing apprehension, there was no significant difference between the two groups.Marilyn Poris (Ph.D., Research Methodology, Hofstra University) is currently serving as Director of Institutional Research a Marist College, where she also teaches courses in statistics.Milton Teichman (Ph.D., English, University of Chicago) is professor of English at Marist College, Poughkeepsie, New York. He has directed writing programs in freshman writing and has supervised research in the field of technology and writing. He has written on innovative approaches to the teaching of writing, as well as on a range of literary subjects from the poetry of Wordsworth to the literature of the Holocaust.  相似文献   
148.
This article proposes a novel mammogram enhancement approach using adaptive intuitionistic fuzzy special set (IFSS) with deep convolutional neural network (called MECNNIFS) for visual interpretation of mammography lesions, lumps, and abnormal cells in low‐dose X‐ray images. The proposed MECNNIFS scheme utilizes the membership grade modification by IFSS on low‐dose X‐ray images (mammography). The suggested model attempts to increase the underexposed and abnormal structural regions such as breast lesions, lumps, and nodules on the mammogram. The proposed algorithm initially separates mammograms using convolutional neural networks (CNNs) into foreground and background areas and then fuzzifies the image by intuitionistic fuzzy set theory. Low‐level features of a mammogram of the adjacent part are integrated with CNN in pixel classification during the separation task stage to improve the performance. Hyperbolic regularization and hesitant score have been applied on fuzzy plane to quantify the uncertainty and fuzziness in spatial domain for the proposed contrast enhancement. Finally, an enhanced mammogram is acquired through the process of defuzzification. The results show better quality and performance for improvement of contrast and visual quality in mammograms compared with other state‐of‐the‐art methods.  相似文献   
149.
Prognostic and predictive value of HER2/neu oncogene in breast cancer   总被引:7,自引:0,他引:7  
Assessment of HER2/neu oncogene has been used as both a prognostic and predictive marker for breast cancer. However, the choice of the best method to assess the status of HER2/neu oncogene in breast cancer tissue remains controversial. A variety of techniques are available to detect HER2/neu gene amplification and overexpression. Tissue-based detection methods by immunohistochemistry (IHC) and/or fluorescence in situ hybridization (FISH) offers a clear advantage over other approaches. FISH is a costly and relatively difficult assay and yet appears to be a better predictor of response to Herceptin (Trastuzumab) therapy and patient outcome. IHC is less expensive and is easier to perform; however, it suffers from a high rate of false negativity and positivity as well as inter-observer variability among pathologists. Suggestions have been made to use IHC as a screening procedure followed by confirmation by FISH in selected cases. Considering the importance of an accurate assessment of HER2/neu oncogene in selecting therapy, a better alternative may be to use FISH as the primary testing for HER2/neu oncogene. Herceptin therapy is associated with several side effects and is expensive. Thus, in the long term, it may be more cost-effective to use the FISH procedure and reduce the possibility of under-treatment or over-treatment of breast cancer patients. In addition, assessment of HER2/neu oncogene on every newly diagnosed early breast carcinoma may not be necessary. Metastatic lesions, when they occur, can be sampled by fine needle aspiration biopsy or core needle biopsy for assessment of HER2/Neu status.  相似文献   
150.
We describe a large-scale simulation of the aftermath of a hypothetical 10kT improvised nuclear detonation at ground level, near the White House in Washington DC. We take a synthetic information approach, where multiple data sets are combined to construct a synthesized representation of the population of the region with accurate demographics, as well as four infrastructures: transportation, healthcare, communication, and power. In this article, we focus on the model of agents and their behavior, which is represented using the options framework. Six different behavioral options are modeled: household reconstitution, evacuation, healthcare-seeking, worry, shelter-seeking, and aiding & assisting others. Agent decision-making takes into account their health status, information about family members, information about the event, and their local environment. We combine these behavioral options into five different behavior models of increasing complexity and do a number of simulations to compare the models.  相似文献   
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