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31.
In 1994, as a result of both programme evaluations which identified students' fears and apprehensions about their practical ability, and a review of the literature on skill acquisition, experiential skills teaching was resumed within the faculty. Having invested considerable finance into the reconstruction of a skills centre to teach skills, it is now imperative that its use be formally evaluated. Part of the evaluative process includes a review of the empirical literature on the acquisition of psychomotor skills in nursing. This paper summarizes this review.  相似文献   
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33.
Clustering is an important data analysis tool for discovering structure in data sets. Although research on conceptual clustering has produced algorithms showing significant advantages over earlier numerical ones, existing methods still present some limitations regarding applicability to biomedical domains. In this paper we describe ADAGIO, a conceptual clustering algorithm combining a low-cost preordering process with a breadth-first incremental control strategy that incorporates merging and splitting operators. Experimental evaluation indicated that the algorithm achieves a good balance between structure discovery performance and computational efficiency, and demonstrated the comparative effectiveness of its missing information handling process. ADAGIO is able to handle qualitative, quantitative and mixed-type data. An application example to a cancer domain is given, where the algorithm was able to suggest interesting epidemiological interpretations.  相似文献   
34.
A 74-year-old patient sought treatment for visual obscuration and clinically had signs of Graves orbitopathy. Past medical history was unremarkable except for the use of antihypertensive medication. During the hospital admission, a fluorescent treponemal antibody absorption test was reactive, indicating infection with syphilis at some time in the past. Visual deterioration despite oral corticosteroid therapy prompted orbital decompression. At the time of surgery, she sustained a globe rupture. Presumably, syphilitic scleritis was responsible, in part, for scleral thinning and weakening, predisposing her to this complication. To the authors' knowledge, globe rupture has not been previously reported during orbital decompression.  相似文献   
35.
The purpose of this study was to compare probing depth resolution achieved by gingivectomy and periodontal flap techniques in the treatment of cyclosporine A- and nifedipine-induced gingival enlargement. Ten kidney transplant patients who were receiving cyclosporine A and nifedipine for at least 6 months participated in the study. Five patients were randomly assigned to the gingivectomy group and 5 patients to the periodontal flap group. Only anterior segments of the oral cavity (canine to canine) were surgically treated. Clinical measurements, including probing depths, plaque index, and gingival sulcus index, were taken at baseline, 6 weeks, 6 months, and 1 year. Results showed that probing depths, while similar for both groups in the first 6 weeks of the study, were significantly shallower for the periodontal flap group when compared to the gingivectomy group at 6 months (2.48 +/- 0.34 mm versus 4.87 +/- 0.79 mm, respectively) and 1 year (322 +/- 0.65 mm versus 6.40 +/- 1.02 mm, respectively). Within its limitations, this study suggests that the pocket reduction achieved by the periodontal flap may be sustained for longer periods of time than by the gingivectomy technique in the treatment of cyclosporine A- and nifedipine-induced gingival enlargement.  相似文献   
36.
The effect of damming on the structure of the macroinvertebrate community and biological quality was studied in nine (the 3–6th order) lowland streams of Estonia, Central—Baltic ecoregion of Europe. Four habitats—reservoirs with accumulated fine sediments, reservoirs with hard bottom, and two corresponding below‐dam areas (both fast‐flowing)—were compared to study whether and how significantly the bottom substrata in dammed areas affected macroinvertebrates and biological quality downstream of dams. The standard kick‐net samples (1.25 m2, complemented with qualitative sample) were collected in autumn 2005—spring 2006. The multimetric biological quality, based on five macroinvertebrate indices (total taxa richness, EPT taxa richness, Average Score Per Taxon, Danish Stream Fauna Index, Shannon diversity) was estimated and compared with reference values. Biological quality in reservoirs with hard bottom and their downstream reaches corresponded to good, or even high quality. Conversely, damming affected biological quality significantly and negatively, above the dam if fine sediments were accumulated. The effect was the strongest within muddy reservoirs themselves (revealing moderate quality only). However, some harmful consequences of mud were observed also downstream of dams. The results also demonstrated that the indices of estimation of organic pollution and/or general quality were able to reflect significant changes in stream flow. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
37.
BACKGROUND AND PURPOSE: Cerebral emboli can be recognized by typical "high-intensity transient signals" (HITS) in the transcranial Doppler (TCD) spectral curves. Patients with potential cardiac sources of embolism are at higher risk for stroke. METHODS: We examined the frequency of HITS in the left middle cerebral artery (MCA) with TCD over periods of 30 minutes in 100 patients having potential cardiac sources of embolism, as indicated by transthoracic or transesophageal echocardiography. RESULTS: Thirty-six (36%) of the patients presented with HITS. Sex, age, sufficient anticoagulation level, antiplatelet therapy, neurological symptoms, and a history of thrombosis had no influence on the prevalence and number of HITS. The patients with a single echocardiographic diagnosis were separated into eight echocardiographically defined groups: patients with (1) atrial fibrillation, (2) coronary artery disease plus ejection fraction of more than 30% including at least three wall segments of hypokinesia/akinesia, (3) coronary artery disease with less than 30% ejection fraction, (4) dilated cardiomyopathy, (5) infectious endocarditis, (6) aortic stenosis, (7) mitral stenosis, and (8) patent foramen ovale. A significant difference in HITS occurrence could not be found in any of the defined groups. Only patients with infectious endocarditis showed a tendency for a higher HITS prevalence. CONCLUSIONS: HITS are common phenomena in patients with potential cardiac sources of embolism. The clinical relevance of these HITS remains unclear.  相似文献   
38.
BACKGROUND: The functional assessment of the startle circuit is usually done by analyzing the acoustic startle response (ASR). However, a startling acoustic stimulus (SAS) also induces changes in the excitability of neural structures that can be demonstrated by studying the SAS-induced change in the behavior of certain neurophysiologic responses. OBJECTIVE: To examine the effects induced by an SAS on voluntary reaction time in patients with parkinsonian syndromes (StartReact effect) and to compare the results with those obtained in a group of age-matched healthy volunteers. METHODS: Twelve patients with idiopathic PD (IPD), seven patients with progressive supranuclear palsy (PSP), seven patients with multisystem atrophy (MSA), and seven healthy age-matched control volunteers performed a simple visual reaction time task and received SAS together with the "go" signal in random trials. RESULTS: Baseline reaction time was significantly slower in PSP patients than in control subjects and MSA patients. The SAS induced a significant shortening of the reaction time in control subjects and in patients with IPD and MSA, but not in patients with PSP. The percentage of reaction time shortening with regard to the baseline values also differed significantly between PSP patients and the other groups of subjects. The StartReact effect was consistent throughout the experiment and showed reduced habituation with repeated testing. CONCLUSIONS: The results are consistent with an abnormal function of the startle circuit in patients with PSP and agree with previous studies using the ASR. The reduced habituation of the StartReact effect favors its clinical applicability in the assessment of differences between patients with parkinsonian syndromes.  相似文献   
39.
The case of a quadricuspid aortic valve diagnosed in adult age is reported. A 67-year-old patient, who had no previous diseases or cardiovascular complaints, presented in the clinic for an embolic occlusion of the left retinal artery. Isolated moderate aortic regurgitation was diagnosed clinically and echocardiographically. For its further evaluation and for seeking embolic sources, multiplane transesophageal echocardiography was performed, which discovered a quadricuspid aortic valve as the cause of aortic regurgitation and major atherosclerotic lesions in the ascending aorta and the aortic arch as possible cause of the embolic event. The fourth, accessory cusp, smaller than the other three, was localized between the non-coronary and left coronary cusp. In the short axis view the quadricuspid aortic valve showed in diastole a "X"-configuration, with a persistent central orifice between the commissures, which was the cause of the regurgitation jet in color Doppler examination, and in the systole a trapezoid opening pattern. In the long-axis view the valve showed a tricuspid closing pattern. The quadricuspid aortic valve can be exactly diagnosed by multiplane transesophageal echocardiography.  相似文献   
40.
In China’s first lunar exploration project, Chang-E 1 (CE-1), a multi-channel microwave radiometer was aboard the satellite, with the purpose of measuring microwave brightness temperature from lunar surface and surveying the global distribution of lunar regolith layer thickness. In this paper, the primary 621 tracks of swath data measured by Chang-E 1 microwave radiometer from November 2007 to February 2008 are collected and analyzed. Using nearest neighbor interpolation based on the sun incidence angle in ...  相似文献   
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