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31.
A synthesis method and an MOS VLSI architecture are presented to realize sequential circuits that have the ability to implement any state machine having N states and m inputs, regardless of the actual sequence specified in the flow table. The design method utilizes binary tree structured logic to implement regular and dense circuits. The desired state sequence can be hardwired with power supply connections or can be dynamically reallocated if stored in a register. This allows programmable VLSI controllers to be designed with a compact size and performance approaching that of dedicated logic. Results of ICV implementations are reported and an example sequence-invariant state machine is contrasted with implementations based on traditional methods  相似文献   
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We describe a novel technique for isolation of sequences that are present in one genome (tracer), but absent in another (driver). Tracer DNA, cleaved with Sau 3A and capped with a single stranded PCR adapter, is allowed to hybridize with an excess of sheared biotinylated driver; biotinylated DNA and its hybrids with the tracer are removed by phenol/chloroform extraction after incubation with streptavidin. After several rounds of subtraction the ends of self-annealed tracer molecules from the nonextractable fraction are filled-in with Tag polymerase and amplified, using the single stranded PCR adapter as a primer. The method has been applied to purification of fragments from a 2.9 kb plasmid added to E. coli DNA at equimolar quantity. Plasmid derived fragments (250-1000 bp), initially comprising 1/1400th part of tracer DNA, were purified to homogeneity after two rounds of subtraction followed by PCR.  相似文献   
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We report a case of left ventricular myxoma with embolization to the left posterior cerebral artery, causing acute visual loss. The tumor was successfully resected and a follow-up echocardiography after 21 months revealed no evidence of tumor recurrence. The patient also had a past history of testicular seminoma. We believe that this is the first case report of an association of cardiac myxoma and testicular seminoma.  相似文献   
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BACKGROUND: Combined treatment of allograft recipients with anti-CD40 ligand and CTLA-4Ig (costimulation blockade) is a powerful promising albeit not consistently tolerizing therapy. It would be desirable to use an effective conventional immunosuppressive regimen in low doses or for a short course as an adjunct; however, cyclosporine treatment drastically blunts the ability of costimulation blockade to produce long-term engraftment. METHODS: Short courses of cyclosporine or rapamycin were compared as adjuncts to costimulation blockade in the murine BALB/c to C3H/He heterotopic cardiac allograft model. RESULTS: Although cyclosporine therapy blocked the capacity of costimulation blockade to produce permanent engraftment, combined rapamycin and costimulation blockade treatment produced permanent engraftment. CONCLUSION: A theoretical basis for the differing effects of cyclosporine and rapamycin upon the outcome of costimulation blockade is forwarded. Combined use of costimulation blockade and rapamycin may provide a means to bring costimulation blockade into the clinic.  相似文献   
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OBJECTIVE: We prospectively compared the ability of two techniques--bone scintigraphy with single-photon emission computed tomography (SPECT) of the chest and CT of the chest--to reveal potential osteosarcoma metastases of the lung. SUBJECTS AND METHODS: Our study included 27 patients with osteosarcoma who prospectively underwent both bone scintigraphy with SPECT of the chest and CT of the chest. The imaging results were compared with outcome or pathologic analysis of any lung lesions found. RESULTS: Eight (30%) of the 27 patients had pulmonary metastases. Four of these eight patients had positive results on both CT studies and bone SPECT studies, with additional lesions detected with bone SPECT in two of these four patients. The other four patients with pulmonary metastases had positive results on CT studies, whereas the results of bone SPECT studies remained negative. The results of bone SPECT studies were negative in the 19 patients without pulmonary metastases. CT, however, showed abnormalities in seven (37%) of the 19 patients, which were eventually attributed to benign conditions. CONCLUSION: Negative results on a bone SPECT study of the chest should not be used to exclude the possibility of lung metastases. However, if the results are positive, a bone SPECT study can be used to confirm abnormalities seen on CT scans and may also reveal subtle lesions missed on CT scans.  相似文献   
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The purpose of this study was to compare the use of bioactive glass to demineralized freeze-dried bone allograft (DFDBA) in the treatment of human periodontal osseous defects. Fifteen systemically healthy patients (6 males and 9 females, aged 30 to 63) with moderate to advanced adult periodontitis were selected for the study. All patients underwent initial therapy, which included scaling and root planing, oral hygiene instruction, and an occlusal adjustment when indicated, followed by re-evaluation 4 to 6 weeks later. Paired osseous defects in each subject were randomly selected to receive grafts of bioactive glass or DFDBA. Both soft and hard tissue measurements were taken the day of surgery (baseline) and at the 6-month re-entry surgery. The clinical examiner was calibrated and blinded to the surgical procedures, while the surgeon was masked to the clinical measurements. Statistical analysis was performed by using the paired Student's t test. The results indicated that probing depths were reduced by 3.07 +/- 0.80 mm with the bioactive glass and 2.60 +/- 1.40 mm with DFDBA. Sites grafted with bioactive glass resulted in 2.27 +/- 0.88 mm attachment level gain, while sites grafted with DFDBA had a 1.93 +/- 1.33 mm gain in attachment. Bioactive glass sites displayed 0.53 +/- 0.64 mm of crestal resorption and 2.73 mm bone fill. DFDBA-grafted sites experienced 0.80 +/- 0.56 mm of crestal resorption and 2.80 mm defect fill. The use of bioactive glass resulted in 61.8% bone fill and 73.33% defect resolution. DFDBA-grafted defects showed similar results, with 62.5% bone fill and 80.87% defect resolution. Both treatments provided soft and hard tissue improvements when compared to baseline (P < or = 0.0001). No statistical difference was found when comparing bioactive glass to DFDBA; however, studies with larger sample sizes may reveal true differences between the materials. This study suggests that bioactive glass is capable of producing results in the short term (6 months) similar to that of DFDBA when used in moderate to deep intrabony periodontal defects.  相似文献   
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A microwave holographic technique for the determination of amplitude and phase of the principal and cross-polarized aperture fields of large reflector antennas is described. The hologram formation process utilizes the elevation over azimuth scanning system normally associated with these antennas, and, in this respect, appears to be unique among other proposed methods of field probing. The present work describes the means used to obtain vital information on the antenna structure such asE- andH-plane phase centers of the feed, and rms values of the reflector surface profile errors. Accurate prediction ofE- andH-plane radiation patterns in the near- and far-field is also demonstrated.  相似文献   
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