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41.
This report describes an unusual nasal foreign body in a 4-year-old boy discovered incidentally in a routine dental radiograph. A small piece of rubber eraser was lodged in the right nasal cavity, causing unilateral nasal obstruction and discharge, sneezing, snoring and breathing difficulty. In this case, discovery of unknown intranasal object was diagnostic for a condition suspected of pathological origin. Dentists may play a significant role in the diagnosis of intranasal foreign objects in children, through careful clinical examination and interpretation of dental radiographs. Early diagnosis is emphasized in order to avoid complications. 相似文献
42.
J Maher F Rutledge H Remtulla A Parkes L Bernardi CF Bolton 《Canadian Metallurgical Quarterly》1995,21(9):737-743
OBJECTIVE: To determine, by retrospective chart analysis, the frequency, type and significance of neuromuscular disorders in patients whose clinical features suggested a neuromuscular cause of failure to wean. BACKGROUND: Failure to wean is a common and difficult problem in critical care units. While a neuromuscular cause may be suspected in some patients, the frequency and type has not been determined utilizing comprehensive electrophysiological studies of limbs and the respiratory system. Such knowledge may aid in patient management and prognosis. METHODS: The clinical setting was a critical care/trauma centre that admits 1500 patients per year, approximately 500 being on ventilators for longer than five days. We analyzed the hospital charts of 40 patients admitted to the unit during three years, whose respiratory assessment suggested a neuromuscular cause for failure to wean from the ventilator. To investigate this possibility, we performed electrophysiological studies of the limbs and also of the respiratory system by phrenic nerve conduction and needle electromyography of the chest wall and diaphragm. The results were compared to 25 healthy controls. RESULTS: 38 of 40 patients (95%) had a neuromuscular disorder: 25--critical illness polyneuropathy, 2--Guillain-Barré syndrome, 4--diabetic and critical illness polyneuropathy, 2--uremic and critical illness polyneuropathy, 10--an abnormality of central drive, 5--unilateral phrenic nerve palsy, 3--a neuromuscular transmission defect, and 5--a primary myopathy. Fifteen (38%) had a combination of disorders. Patients with more severe polyneuropathy took longer to wean, a mean of 136 versus 52 days (p = 0.007). The severity of the polyneuropathy had no effect on mortality. CONCLUSIONS: Electrophysiological studies of limbs and the respiratory system are together valuable in confirming the presence, and identifying the specific type of neuromuscular cause for difficulty in weaning from the ventilator. This information is important in patient management and prognosis. 相似文献
43.
Jay J. Williams Janet C. Rutledge Aggelos K. Katsaggelos Dean C. Garstecki 《The Journal of VLSI Signal Processing》1998,20(1-2):7-23
Current video conference and phone systems do not provide the necessary temporal resolution and motion for speechreading. In this paper the perceptual boundaries which effect speechreading performance are investigated. Analysis of the relationships between viseme groupings, accuracy of viseme recognition and presentation frame rate is presented based on the results of subject testing. Results reveal a minimum frame rate of 10 frames per second (fps) for distinguishing viseme groupings. Confusion analysis results demonstrate the importance of the tongue and teeth oral features for speechreading. These results are critical to the design of speech-assisted video systems to enhance speechreading for individuals with impaired hearing. 相似文献
44.
45.
Cheh-Ming Liu Emilio A. Sovero Wu Jing Ho J. A. Higgins David B. Rutledge 《Journal of Infrared, Millimeter and Terahertz Waves》1995,16(11):1901-1909
A 36-element monolithic grid amplifier has been fabricated. The peak gain is 5 dB at 40.8 GHz with a 3-dB bandwidth of 1.4 GHz. The active elements are pairs of heterojunction-bipolar-transistor's (HBT's). The individual transistors in the grid have a maximum oscillation frequency,f max , of 100 GHz. The grid includes base stabilizing capacitors which result in a highly stable grid. This is the first report of a successful monolithic grid amplifier. 相似文献
46.
The antioxidant properties of butein, isolated from Dalbergia odorifera T. Chen, were investigated in this study. Butein inhibited iron-induced lipid peroxidation in rat brain homogenate in a concentration-dependent manner with an IC50, 3.3+/-0.4 microM. It was as potent as alpha-tocopherol in reducing the stable free radical diphenyl-2-picrylhydrazyl (DPPH) with an IC0.200, 9.2+/-1.8 microM. It also inhibited the activity of xanthine oxidase with an IC50, 5.9+/-0.3 microM. Besides, butein scavenged the peroxyl radical derived from 2,2-azobis(2-amidinopropane) dihydrochloride (AAPH) in aqueous phase, but not that from 2,2-azobis(2, 4-dimethylvaleronitrile) (AMVN) in hexane. Furthermore, butein inhibited copper-catalyzed oxidation of human low-density lipoprotein (LDL), as measured by conjugated dienes and thiobarbituric acid-reactive substance (TBARS) formations, and electrophoretic mobility in a concentration-dependent manner. Spectral analysis revealed that butein was a chelator of ferrous and copper ions. It is proposed that butein serves as a powerful antioxidant against lipid and LDL peroxidation by its versatile free radical scavenging actions and metal ion chelation. 相似文献
47.
RH Rutledge 《Canadian Metallurgical Quarterly》1997,225(2):239-240
48.
JR Hibbs JM Douglas FN Judson WL McGill CA Rietmeijer EN Janoff 《Canadian Metallurgical Quarterly》1997,25(2):195-199
The hemagglutinating virus of Japan (HVJ)-liposome method involves the entrapment of DNA and nuclear protein within liposomes and the use of HVJ to enhance liposome fusion with cell membranes. This method has been used successfully for in vivo gene transfer to various types of tissue. In this study, we investigated whether this method transfers genes effectively to normal and malignantly transformed keratinocytes in vivo. We applied HVJ-liposome complex (HLC) containing the beta-galactosidase gene to the tape-stripped skin of hairless rats and detected the enzyme activity in the keratinocytes of the treated skin. Comparison of this method with the naked DNA injection method, which was shown recently to be useful for in vivo gene transfer to keratinocytes, demonstrated that the transfer efficiency of the latter was about 5 times higher than that of the former. We assessed the efficacy of the HVJ-liposome method for gene transfer to transformed keratinocytes by examining the effect of HLC containing the herpes simplex virus thymidine kinase gene on the growth of mouse squamous cell carcinomas. Local injection of HLC into the tumors followed by administration of ganciclovir to mice resulted in tumor growth inhibition. These results indicate that the HVJ-liposome method is suitable for in vivo gene transfer to keratinocytes; also that this method may prove a good tool for basic research into keratinocyte biology and future keratinocyte gene therapy. 相似文献
49.
L3 and L4 stages of H.polygyrus were prevented from developing further and were probably killed within 24 h of treatment with ivermectin although total parasite burdens, particularly when treatment was given 4-6 days after infection, declined over a longer period lasting several days. Strong resistance to challenge infection was expressed by infected mice dosed with ivermectin during the tissue phase of larval development. Even immunizing infections as brief as 12-36 h (when only L3 larvae would have been present in the mucosa) elicited strong acquired immunity. When infections were terminated 4-6 days after infection, acquired resistance was 95-100%. The stronger resistance of mice exposed to both L3 and L4 stages was associated with the recognition of low molecular weight polypeptides in adult worm homogenate and there was a highly significant correlation between percentage protection and anti-L4/anti-adult worm serum IgG1 antibodies. 相似文献
50.
Using the patient as teacher: A training method for family practice residents in behavioral science.
Lewis Janis L.; Stokes DeVon R.; Fischetti Lawrence R.; Rutledge Aaron L. 《Canadian Metallurgical Quarterly》1988,19(3):349
Since the inception of family medicine as a specialty in allopathy and osteopathy in 1969 and 1973, respectively, there has been a need to develop integrative approaches of teaching behavioral science concepts without violating the scope of practice limitations between the fields. We describe a collaborative training method by which we attempt to achieve this balance. Residents referring patients for mental health services are involved in all phases of the mutual patient's treatment. The intake, recommendation, and feedback sessions are videotaped with both health care providers present. In this method, the necessity of keeping within the limited time constraints of medical schedules is recognized, the application of behavioral science concepts over theory is emphasized, and the role of the behavioral scientist as an equal partner in the team approach to health care is strengthened. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献