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91.
Presented a social communication task to 215 Canadian high school students (Grades 8-13). Results show that correctness and group agreement interacted with grade level, producing varying degrees of perceived competence relative to a simulated group. For Ss in Grades 8-10 only, the experimental manipulation of relative competence influenced conformity; Ss who were told that they were more competent than the group conformed less than those who were told that they were either less competent than or as competent as the group. Ss who perceived themselves to be more competent than the group also conformed less. Other findings are that: (a) females showed significantly higher conformity, (b) Ss in Grades 11-13 indicated more suspicion and awareness of the possibility of deception, and (c) no differences in conformity existed between suspicious and nonsuspicious Ss. (French summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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PURPOSE: This multicenter, randomized phase III clinical trial evaluated the efficacy of etoposide plus carboplatin (EC) versus etoposide plus cisplatin (EP) in good-risk germ cell tumor (GCT) patients. PATIENTS AND METHODS: Between October 1986 and December 1990, 270 patients with good-risk GCTs were randomized to receive four cycles of either EP or EC. The etoposide dose in all patients was 100 mg/m2 on days 1 through 5. EP patients received cisplatin at 20 mg/m2 on days 1 through 5 and therapy was recycled at 21-day intervals. For EC patients, the carboplatin dose was 500 mg/m2 on day 1 of each cycle and the EC recycling interval was 28 days. RESULTS: Two hundred sixty-five patients were assessable: 131 patients treated with EC and 134 treated with EP. One hundred fifteen of 131 assessable patients (88%) treated with EC achieved a complete response (CR) versus 121 of 134 patients (90%) treated with EP (P = .32). Sixteen patients (12%) treated with EC relapsed from CR versus four patients (3%) treated with EP. Therefore, 32 patients (24%) who received carboplatin experienced an event (incomplete response [IR] or relapse) compared with 17 of 134 patients (13%) who received cisplatin (P = .02). At a median follow-up of 22.4 months, event-free and relapse-free survival were inferior for patients treated with EC (P = .02 and P = .005, respectively). No difference in overall survival was evident (P = .52). CONCLUSION: Two-drug therapy with EC using this dose and schedule was inferior to therapy with EP. Cisplatin remains as the standard platinum analog in the treatment of patients with good-risk GCTs. Carboplatin should be restricted to investigational trials in GCT.  相似文献   
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A thick radiator neutron spectrometer has been constructed in which protons recoiling forward in the stilbene escape from the crystal and are detected in a silicon surface barrier counter. The coincident pulses from the two counters are recorded using a two-parameter analyzer. The instrument has been used to investigate (1) the response of stilbene to protons originating within the scintillator and (2) the behavior of the pulse shape discrimination as a function of the energy deposited in the stilbene crystal. The response function, which is required for the analysis of the neutron spectra, is compared with one obtained for protons incident externally on the same crystal. Small differences between the two response functions are observed and analyzed. Concerning the behavior of the pulse shape discrimination between protons and electrons it is found that, for internally generated protons, the ability to separate protons from electrons worsens as the energy deposited in the scintillator decreases. This contrasts with the behavior for protons which stop in the scintillator. The results support the hypothesis that the fast component of the pulse decreases with increasing stopping power whereas the slow component depends primarily on the energy lost. The results are analyzed and may be interpreted with certain assumptions to give the ratio of the fast and slow scintillation components.  相似文献   
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PURPOSE: The ability of magnetic resonance (MR) angiography to depict visceral and renal vessels was evaluated in patients with abdominal aortic aneurysms (AAAs). PATIENTS AND METHODS: MR sequences (sagittal T1-weighted, two-dimensional coronal, and three-dimensional axial time-of-flight) were compared in a prospective blinded fashion with conventional angiograms obtained preoperatively in 23 patients with AAAs. Results were correlated with surgical findings when available. RESULTS: Operative aortic clamp site was correctly predicted with conventional angiography in 95% of patients and with MR angiography in 86% (P > .1). Aneurysm neck measurements obtained with the two modalities were within 1 cm in 91% of cases. With conventional angiography as the standard of reference, 96% of all renal arteries were identified on MR angiograms but 36% of accessory arteries were missed. MR angiography enabled identification of patients who had at least one renal artery stenosis greater than 50% with a sensitivity of 100% and specificity of 89%. For identifying individual renal artery, celiac artery, and superior mesenteric artery stenoses of similar severity, the sensitivity and specificity were 67% and in excess of 96%, respectively. The celiac artery could not be evaluated in one case. CONCLUSION: The results of this small study suggest that the role of MR angiography in the preoperative evaluation of AAA warrants further investigation.  相似文献   
98.
There have been increasing concerns about the security issues of wireless transmission of multimedia in recent years. Wireless networks, by their natures, are more vulnerable to external intrusions than wired ones. Therefore, many applications demand authenticating the integrity of multimedia content delivered wirelessly. In this work, we propose a framework for jointly authenticating and coding multimedia to be transmitted over heterogeneous wireless networks. We firstly provide a novel graph-based authentication scheme which can not only construct the authentication graph flexibly but also trade-off well among some practical requirements such as overhead, robustness and delay. And then, a rate-distortion optimized joint source-channel coding (JSCC) approach for error-resilient scalable encoded video is presented, in which the video is encoded into multiple independent streams and each stream is assigned forward error correction (FEC) codes to avoid error propagation. Furthermore, we consider integrating authentication with the specific JSCC scheme to achieve a satisfactory authentication results and end-to-end reconstruction quality by optimally applying the appropriate authentication and coding rate. Simulation results show the effectiveness of the proposed authentication-coding scheme for multimedia over wireless networks.  相似文献   
99.
The purpose of this study was to find criteria characteristic for patients in need of care and social services. The criteria should serve as a guideline for patients and staff to facilitate care planning before discharge. The sample consisted of 49 patients, born before 1925, in need of emergency inpatient treatment, admitted to medical- or orthopaedic wards. Data of the patient's self care needs were collected by interviews, assessment of self care status and need of treatment. The patients could be divided into three groups depending on type of discharge. Group A (n = 27) discharged home, group B (n = 7) discharged to geriatric clinic and group C (n = 15) discharged and in need of further care and social services. Criteria indicating the patients further assistance from the community were in group C (medical- and orthopaedic wards) deficit in daily living activities and locomotion. Group B had an increased need of support from the physiotherapist and the occupational therapist, in locomotion as well as daily living activities The physician's assessment showed that the criteria behind the decision "no further medical treatment appropriate" and "ready for discharge" were not related to medical impairment but to lack of self care, need of care, rehabilitation and social services.  相似文献   
100.
The history and purpose of the investigation are outlined and reports are made on (1) fineness determinations, chemical analyses, softening range, softening points, “true” specific gravity, thermal expansion, and petrographic analyses of the individual feldspars; (2) the results of porosity, volume shrinkage during firing, color and translucency, mechanical strength, petrographic analyses, effect of feldspar used on relative “glaze fit,” thermal expansion, and elasticity determinations on vitreous and semivitreous bodies in which feldspar is the only variable component.  相似文献   
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