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991.
JW Becker W Burke G McDonald PA Greenberger WR Henderson ML Aitken 《Canadian Metallurgical Quarterly》1996,109(6):1536-1540
BACKGROUND: Underestimation of allergic bronchopulmonary aspergillosis (ABPA) prevalence in the cystic fibrosis (CF) population is suspected due to nonuniform diagnostic criteria, nonspecific signs and symptoms, assessment during asymptomatic intervals, and physician nonaggressiveness in making the diagnosis. OBJECTIVE: To define the prevalence of ABPA in adult patients with CF, as the increased duration of bronchiectasis may increase the probability of Aspergillus fumigatus (Af) colonization. We also sought to determine whether atopy increases the prevalence of ABPA in adults with CF. METHODS: We examined a cross-sectional population of adult patients with CF at the University of Washington for 1 year. RESULTS: Information was collected on 53 of 65 (82%) patients. Fifteen of 51 (29%) had an immediate skin test reaction to Af, and 30 of 51 (59%) had at least one positive skin test. Increased total serum IgE (>450 IU/mL) was present in 0 of 53; increased IgE-Af and IgG-Af were found in 12 of 53 (23%) and 9 of 53 (17%), respectively; 24 of 53 (45%) had Af-precipitins. Peripheral blood eosinophilia was present in one patient. Eight of 49 (16%) patients' sputum cultures grew Af. ABPA-CB (ABPA-central bronchiectasis) was present in one patient and ABPA-S (ABPA-seropositive) in no patients. Atopy was present in 20 of 51 (39%). CONCLUSION: There was a low prevalence of ABPA in the adult CF population despite frequent immunologic responses to Af. The prevalence of ABPA was too small to determine an association with atopy. 相似文献
992.
ME Mackenzie WT Davies MB Farnell AL Weaver DM Ilstrup 《Canadian Metallurgical Quarterly》1996,131(10):1083-1085
OBJECTIVE: To determine if the presence of duodenal diverticula predisposes to the development of common bile duct stones. DESIGN: Cohort study; median follow-up, 10.0 years (25th and 75th percentiles, 5.2 and 16.1 years, respectively). SETTING: Tertiary care center. PATIENTS: One hundred fifty-seven patients with radiologically diagnosed duodenal diverticula who had undergone cholecystectomy from 1950 through 1987 and were asymptomatic at the initiation of follow-up. MAIN OUTCOME MEASURES: All patients were followed up for evidence of recurrent biliary tract disease to the following end points: (1) evidence of choledocholithiasis demonstrated by radiologic surgical, or biochemical means and (2) clinical or biochemical evidence of biliary pancreatitis. RESULTS: Of the 157 patients in the study cohort, 13 patients were categorized as having had recurrent biliary tract disease. Using the Kaplan-Meier survivorship method, the cumulative probabilities of recurrent biliary tract disease in patients with radiologically diagnosed duodenal diverticula were 3.6% at 5 years (95% confidence interval, 0.5-6.9), 5.5% at 10 years (95% confidence interval, 1.5-9.4), and 10.2% at 15 years (95% confidence interval, 3.8-16.7). Age, common bile duct exploration and choledochotomy, and the presence of common bile duct dilatation were not found to be significantly associated with recurrence based on a univariate analysis of risk factors by means of the log-rank statistic. CONCLUSIONS: For patients with radiologically diagnosed, second-portion duodenal diverticula, the risk of developing recurrent bile duct stones after cholecystectomy is lower than has been suggested in previous studies. In the absence of concurrent choledocholithiasis, sphincterotomy or biliary bypass at the time of cholecystectomy seems unwarranted. 相似文献
993.
Long-term changes in soft tissue landmark positions were examined in 49 patients following superior repositioning of the maxilla by Le Fort I osteotomy. From presurgery to 1 year, on average the upper lip moved up one third the distance that the upper incisor and point A did, but there was considerable variability. In 25% of the patients the upper lip moved up more than 2 mm, and in 6% it moved up more than 4 mm. As the mandible rotated upward and forward in response to the maxillary movement, soft tissue movements paralleled the adjacent hard tissue movements almost exactly in the absence of genioplasty. From 1 to 5 years postsurgery, in 25% of the patients the maxilla moved downward more than 2 mm, and the mandible rotated down and back, often without relapse of occlusal relationships. In both jaws, long-term changes in soft tissue landmarks exceeded hard tissue changes, meaning soft tissue points tended to move downward even if hard tissue points were stable and moved down more than the corresponding hard tissue points when skeletal changes occurred. 相似文献
994.
The effect of Matrigel, a solubilised tissue basement membrane extract, has been investigated on the tumorigenicity of 3 breast (MCF-7, T47D and MDA.MB.231) and 5 ovarian [PEO1, PEO1 cDDPr, PEO4, PEO14 and OV(hyg)CAR3] carcinoma cell lines. In the absence of Matrigel, the PEO14 and MDA.MB.231 cell lines produced take rates of 30% and 50%, respectively, while the other cell lines either did not develop or only occasionally developed as tumours. With Matrigel, 100% take rates were achieved for 7 of the 8 cell lines (MCF-7, T47D, MDA.MB.231, PEO1, PEO1 cDDPr, PEO4 and PEO14); in the remaining cell line [OV(hyg)CAR3] 2/6 (33%) tumours grew. Xenografts established with Matrigel could be transferred into recipient animals and grown in the absence of Matrigel, suggesting that Matrigel is necessary only for initial establishment of tumours. Furthermore, cells which had been re-established from a T47D xenograft and then inoculated into mice without Matrigel showed a take rate greater than that of the original cell line but less than that of the xenograft. In conclusion, Matrigel has proven to be extremely useful in establishing a variety of cell lines as xenografts. 相似文献
995.
SL Hu P Polacino V Stallard J Klaniecki S Pennathur BM Travis L Misher H Kornas AJ Langlois WR Morton RE Benveniste 《Canadian Metallurgical Quarterly》1996,51(1-2):115-119
Using pathogenic simian immunodeficiency virus (SIV) infection of macaques as a model, we explored the limits of the protective immunity elicited by recombinant subunit vaccines and examined factors that affect their efficacy. Envelope gp 160 vaccines, when used in a live recombinant virus-priming and subunit-protein-boosting regimen, protected macaques against a low-dose, intravenous infection by a cloned homologous virus SIVmne E11S. The same regimen was also effective against intrarectal challenge by the same virus and against intravenous challenge by E11S grown on primary macaque peripheral blood mononuclear cells (PBMC). However, only limited protection was observed against uncloned SIVmne. Priming with live recombinant virus was more effective than immunization with subunit gp 160 alone, indicating a potential advantage of native antigen presentation and the possible role of cell-mediated immunity in protection. Whole gp 160 was more effective than the surface antigen (gp 130), even though both antigens elicited similar levels of neutralizing antibodies. Animals immunized with the core (gag-pol) antigens failed to generate any neutralizing antibody and were all infected following challenge. However, their proviral load was 10-100-fold lower than that of the control animals, indicating that immune mechanisms such as cytotoxic T lymphocytes (CTL) may play a role. Finally, animals immunized with both the core and the envelope antigens generated significant protective immunity, even with relatively low neutralizing antibodies. Taken together, these results indicate that multiple mechanisms may contribute to protection. It may therefore be advantageous to incorporate multiple antigens in the design of recombinant subunit vaccines against acquired immunodeficiency syndrome (AIDS). 相似文献
996.
997.
Eleven unassembled metal backed patellar interfaces were inoculated with 0.1 ml of Sportol (Bacillus subtilis variety niger spore) and then assembled. Ten of the 11 implants were exposed to 1/2 of a standard ethylene oxide sterilization cycle. The remaining implant was left unsterilized as a control. All the implants were separately incubated in soybean casein digest broth for 7 days at 30 degrees to 35 degrees C and tested for positive growth of Bacillus subtilis. To measure residual ethylene oxide content, 4 ultrahigh molecular weight polyethylene tibial inserts were exposed to a full ethylene oxide sterilization cycle. The implants were removed from the sterilization chamber and tested for residual ethylene oxide at 3, 5, 8, and 9 days after sterilization using an exhaustive extraction headspace technique. Residual ethylene oxide was measured in 3 additional implants 26 days after sterilization. No growth of Bacillus subtilis occurred on any of the 10 inoculated and ethylene oxide sterilized metal backed patellar components, whereas positive growth occurred on the inoculated, unsterilized control implant. Residual ethylene oxide measured in the tibial inserts at 3, 5, 8, and 9 days after sterilization was 23, 15, 12, and 9 ppm, respectively. Twenty-six days after sterilization, residual ethylene oxide was below the minimum detectable level of the measurement technique (5 ppm). 相似文献
998.
Kaliuretic peptide is a recently discovered potent stimulator of potassium and water excretion. Its role in modulating renal water handling in cirrhotic patients has not been defined. The responses of circulating kaliuretic peptide and atrial natriuretic factor in 8 cirrhotic subjects to water immersion were significantly greater (p < 0.05) than those of 7 healthy volunteers. With cessation of immersion, atrial natriuretic factor decreased within 30 min to preimmersion values, whereas kaliuretic peptide remained significantly elevated > 1 h, suggesting a slower clearance for kaliuretic peptide. The peak diuretic response to immersion corresponded in a temporal fashion to the peak circulating concentration of kaliuretic peptide, suggesting a possible physiological role of kaliuretic peptide in modulating volume homeostasis in cirrhotic humans. 相似文献
999.
SH Rokni EC Benson DL Burke TM Jenkins JC Liu G Nelson WR Nelson HE Smith P Tenenbaum V Vylet DR Walz 《Canadian Metallurgical Quarterly》1996,71(5):786-794
The Final Focus Test Beam (FFTB) is a new beam line at the Stanford Linear Accelerator Center designed to test new beam optics concepts, hardware, and techniques necessary to achieve and measure the small spot sizes required for future generations of high-energy e+e- linear colliders. The FFTB takes a 47 GeVc-1, 1 kW electron beam at the end of the Stanford Linear Accelerator Center linear accelerator and transports it to the FFTB beam dump. A radiation protection system was designed and installed for the FFTB with the primary goal that the integrated dose equivalent outside the shielding resulting from beam loss would not exceed 10 mSv y-1. This system is comprised of shielding, a beam containment system and a personnel protection system. This paper presents various aspects of radiation safety at Stanford Linear Accelerator Center that were considered in the design of the FFTB radiation protection system. Beam tests were conducted in which the performance of various beam containment devices and the shielding effectiveness were evaluated. Preliminary results from these tests are presented. 相似文献
1000.
MR Prausnitz JA Gimm RH Guy R Langer JC Weaver C Cullander 《Canadian Metallurgical Quarterly》1996,85(12):1363-1370
Scanning confocal fluorescence microscopy was used to image localized regions of calcein transport across human stratum corneum during constant low-voltage (iontophoresis) and pulsed high-voltage exposures. Following an electrical protocol, imaging revealed regions of fluorescence which were interpreted as sites where transport of a fluorescent probe (calcein) into the stratum corneum had taken place. Electrically-assisted transport of calcein, whether enhanced by iontophoresis or high-voltage pulsing, appears to occur through intercellular and, to some extent, transcellular pathways into localized regions of stratum corneum that are not associated with appendages. Uniquely associated with the highest voltage pulses used (300 V across the skin) was the appearance of small, brightly fluorescent areas containing nonfluorescent interiors, i.e., fluorescent "rings". We present evidence which suggests that the dark interiors represent sites through which transport occurred during pulsing, but where calcein was no longer present at the time of imaging. Transport of charged microspheres into the stratum corneum was also observed. 相似文献