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991.
Medical records, angiograms and operative records of 28 patients with partial anomalous pulmonary venous connection (PAPVC) were reviewed. Twenty patients had one anomalous pulmonary vein (APV), and 8 had more than two APVs. Twenty-five patients (89%) had APVs originating from the right lung, 2 (7%) from the left lung and 1 (4%) from both lungs. In the 25 patients with APVs originating from the right lung, 9 had APVs draining into the superior vena cava (SVC), 13 into the right atrium (RA), 1 into the inferior vena cava (IVC) and 2 into both the SVC and RA. In the 2 patients with APVs originating from the left lung, 1 had APVs draining into the RA, and the other had APVs draining into the innominate vein. The patient with APVs originating from both lungs had connection to the IVC. Twenty-three patients (82%) had additional cardiovascular defects. Surgery was performed in 13 patients who had pulmonary/systemic flow ratios greater than 2.0. The patients have done well after surgery. In 7 patients, we were unable to accurately determine the number or sites of drainage of APVs prior to surgery. We conclude that selective pulmonary angiography is indispensable for the accurate diagnosis of PAPVC. 相似文献
992.
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994.
Neutron fields in six locations inside containment of a CANDU600-PHWR power plant were characterized using Bonner-sphere spectrometry. Unfolded fluence spectra were used to predict and understand the behavior of a rem meter (a moderator-type dose equivalent survey instrument). The suitability of employing commonly-used sources such as 241Am-Be for calibrating the rem meter was investigated by calculational means. Results of these calculations suggest that employing a calibration field more representative of the power-plant fields would likely provide more accurate dose equivalents. 相似文献
995.
JC Sinkford 《Canadian Metallurgical Quarterly》1998,65(4):39-42
This article is a survey of the current status and likely future changes in dental education in the context of changing demographics, economics, and higher education. Topics covered include changes in faculty, students, curriculum, research, and dental practice. 相似文献
996.
JC Hiott 《Canadian Metallurgical Quarterly》1998,94(12):546-547
997.
KJ Madaras-Kelly BE Ostergaard LB Hovde JC Rotschafer 《Canadian Metallurgical Quarterly》1996,40(3):627-632
998.
N Muthukumar D Kondziolka LD Lunsford JC Flickinger 《Canadian Metallurgical Quarterly》1998,140(4):315-20; discussion 320-1
Radical microsurgical resection is the procedure of choice for tentorial meningiomas. Despite advances in microsurgery, tentorial meningiomas continue to challenge surgeons and patients. To evaluate the response of tentorial meningiomas, we evaluated 41 patients who had Gamma knife stereotactic radiosurgery during a 9 year period. Patient age varied from 32 to 79 years. Headache, trigeminal neuralgia, or facial paraesthesia were the most common presenting symptoms. Sensory deficits in the distribution of the trigeminal nerve were the most common finding. Eighteen patients (44%) had undergone between 1 and 5 (mean, 1.9) resections prior to radiosurgery; 23 had tumors diagnosed by neuroimaging. The average tumor diameter in this series was 20 mm. The maximum tumor dose varied from 24 to 40 Gy (mean, 30.5 Gy), and the tumor margin dose varied from 12 to 20 Gy (mean, 15.3 Gy). During the average follow-up interval of 3 years (range, 1-8 years), 19 patients had clinical improvement, 20 remained stable, and 2 patients deteriorated. Follow-up imaging showed a reduction in tumor size in 18 patients, no further tumor growth in 22, and an increase in tumor size in one (overall tumor control rate of 98%). Stereotactic radiosurgery using the Gamma Knife was a safe and effective primary or adjuvant treatment for patients with tentorial meningiomas. 相似文献
999.
JC Vié B De Thoisy P Fournier C Fournier-Chambrillon C Genty J Kéravec 《Canadian Metallurgical Quarterly》1998,45(4):399-410
The cost-effectiveness of two different methods of prevention of morbidity and mortality due to Plasmodium falciparum malaria, vaccination and impregnation of mosquito nets with permethrin, was compared. The analysis was performed with reference to the cohort of all children born in The Gambia in 1990 and protected for 5 years, using estimates of costs from studies in The Gambia. The vaccine was assumed to be given in three doses before the age of 6 months, through the Expanded Programme of Immunization, and to remain effective up to the age of 5 years. The bednets were assumed to be impregnated at 6-monthly intervals over the 5-year period. The expected number of deaths and attacks due to P. falciparum in the first 5 years of the 1990 cohort's lives were estimated from published literature. The numbers of deaths and attacks averted by the two strategies were then estimated by decision analysis, using the best estimates of effectiveness available in the literature. The vaccine strategy would have averted an estimated 743 deaths and 50,502 malaria attacks, whereas the net impregnation would have averted 1537 deaths and 69,415 attacks. The estimated cost per death averted was U.S. $252 for the vaccine and U.S. $711 for net impregnation. The estimated cost per P. falciparum attack averted was U.S. $3.71 for the vaccine and U.S. $15.75 for net impregnation. Sensitivity analysis, examining the effect of varying the vaccine cost or insecticide cost, the efficacy of the vaccine or net impregnation, and the percentage coverage of the population, confirmed the greater cost-effectiveness of the vaccine strategy for either of the outcomes examined under the conditions of the model. However, limitations on the absolute number of deaths and malaria attacks which can averted by currently available vaccines demonstrate that a vaccine of higher efficacy would be highly desirable. 相似文献
1000.
UB Balasuriya JF Evermann JF Hedges AJ McKeirnan JQ Mitten JC Beyer WH McCollum PJ Timoney NJ MacLachlan 《Canadian Metallurgical Quarterly》1998,213(11):1586-9, 1570
A virus isolated from an aborted equine fetus was determined to be antigenically distinct from several other strains of equine arteritis virus (EAV) by use of a neutralization assay with a large panel of neutralizing monoclonal antibodies. The virus was readily neutralized by polyclonal equine anti-EAV serum. Comparative nucleotide and amino acid sequence analyses indicated that the virus (WA97) isolated from the aborted fetus was virtually identical to a virus (S1971) isolated from imported semen used to inseminate another mare on the farm. Phylogenetic analysis indicated that the WA97/S1971 virus was more related to European than to North American strains of EAV. These sensitive molecular procedures may be useful for epidemiologic investigations of EAV infections. Screening and certification of stallions and frozen equine semen would prevent dissemination of pathogenic strains of EAV. 相似文献