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991.
992.
JA Gallego Sánchez A Astobieta Odriozola J Alvarez Martínez JG Ibarlucea González J Larrinaga Simón C Bernuy Malfaz 《Canadian Metallurgical Quarterly》1998,22(9):770-772
Incidence of prostate disease has seen a sudden boost over the last few years as a result of an increase in male life expectancy. Prostate carcinoma is the third most common cause of cancer mortality in Spain. Post-mortem studies reveal that this is the most prevalent neoplasia in the elderly. 30% of all males over 50 years could host malignant cells in their prostate, although only 20% of these neoplasias have clinical manifestations. Prostate carcinoma expansion occurs by local spreading, as well as lymph and blood dissemination. Local spreading to the urethra, bladder neck, trigonous and seminal vesicles is frequent. Lymph dissemination to obturating, hypogastric, iliac, presacral and paraaortic nodes is a major path for metastasis. Bone metastasis with increased acid phosphatase is the most illustrative sign of prostate adenocarcinoma expansion. Visceral metastasis occur more frequently in lungs, liver and renal glands. There is a 0.3% likelihood of skin metastasis from prostate adenocarcinoma. Considering the rareness of skin metastasis from prostate adenocarcinoma, the case reported in the present paper, first evidence of a prostate carcinoma, is even more exceptional. 相似文献
993.
Monolithically integrated multiwavelength grating cavity laser 总被引:1,自引:0,他引:1
Oh Kee Kwon Kang Ho Kim Eun Deok Sim Jong Hoi Kim Kwang Ryong Oh 《Photonics Technology Letters, IEEE》2005,17(9):1788-1790
A multiwavelength grating cavity laser is reported using a novel design for a multichannel light source based on an etched diffraction grating. Following the design, the compact eight-channel device capable of fine-tuning has been realized by monolithically integrating semiconductor optical amplifiers, various passive waveguides, and deeply etched grating, providing high butt-coupling efficiency, and low waveguide losses. As a result, the sidemode suppression ratio in excess of 45 dB over all channels was achieved. 相似文献
994.
995.
996.
F. H. C. Kelly Mak Fong Keng Chua Gek Sim 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1972,22(7):857-862
A study of the size distribution of calcium carbonate particles obtained by precipitation in a sucrose medium containing different polar additives has been made, including a series of tests to determine the polar property of the precipitate surface via electrophoresis and measurements of heat of adsorption. A mechanism of polar growth has also been suggested to explain the present results. 相似文献
997.
Dąbrowski JM Krzykawska M Arnaut LG Pereira MM Monteiro CJ Simões S Urbańska K Stochel G 《ChemMedChem》2011,6(9):1715-1726
Chlorins have intense red absorptions and high tumor affinities that make them interesting candidates for photodynamic therapy (PDT) of cancer. This paper reports cytotoxicity, phototoxicity, in vitro cellular uptake, and in vivo biodistribution and PDT efficacy of a synthetic chlorin derivative (TCPCSO3H) towards Cloudman melanoma cells (S91). No cytotoxic effects were observed in vitro at concentrations up to 20 μm, and no toxicity was observed in vivo in DBA mice with doses up to 2 mg kg?1. Pharmacokinetics and biodistribution of TCPCSO3H were evaluated in vivo in DBA mice bearing S91 tumors. TCPCSO3H demonstrated preferential accumulation in S91 mouse melanoma, with tumor‐to‐normal tissue ratios of 5 and 11 for muscle and skin, respectively, 24 h after intravenous injection of 2 mg kg?1. Photodynamic therapy performed under these conditions with 70 mW cm?2 diode laser irradiation at 655 nm for 25 min (total light dose=105 J cm?2) resulted in scab formation, followed by temporary or permanent (>60 days) tumor remission. According to the Kaplan–Meier analysis, the median survival time of the control group was 9 days, whereas that of the treated group was 38 days. 相似文献
998.
Dąbrowski JM Urbanska K Arnaut LG Pereira MM Abreu AR Simões S Stochel G 《ChemMedChem》2011,6(3):465-475
The in vitro phototoxicity of a photostable, synthetic, water‐soluble, halogenated bacteriochlorin, 5,10,15,20‐tetrakis(2‐chloro‐5‐sulfophenyl)bacteriochlorin (TCPBSO3H), toward mouse melanoma (S91) cells is ~60‐fold higher than that of the analogous porphyrin, and is associated with very weak toxicity in the dark; 90 % of S91 cells were killed in response to a light dose of 0.26 J cm?2 in the presence of [TCPBSO3H]=5 μM . In vivo toxicity toward DBA mice is very low, even at doses of 20 mg kg?1. In vivo pharmacokinetics and biodistribution of TCPBSO3H were studied in DBA mice with S91 tumors; 24 h after intraperitoneal injection of 10 mg kg?1, TCPBSO3H demonstrated preferential accumulation in S91 mouse melanoma, with tumor‐to‐normal tissue ratios of 3 and 5 for muscle and skin, respectively. Photodynamic therapy (PDT) performed under these conditions, with 90 mW cm?2 diode laser irradiation at λ 750 nm for 20 min (total light dose of 108 J cm?2), resulted in tumor regression. Tumor recurrence was observed only approximately two months after treatment, confirming the efficacy of this PDT against melanoma. 相似文献
999.
Reduced graphene oxide (rGO) supported highly porous polycrystalline V(2)O(5) spheres (V(2)O(5)/rGO) were prepared by using a solvothermal approach followed by an annealing process. Initially, reduced vanadium oxide (rVO) nanoparticles with sizes in the range of 10-50 nm were formed through heterogeneous nucleation on rGO sheets during the solvothermal process. These rVO nanoparticles were oxidized to V(2)O(5) after the annealing process in air at 350 °C and assembled into polycrystalline porous spheres with sizes of 200-800 nm. The weight ratio between the rGO and V(2)O(5) is tunable by changing the weight ratio of the precursors, which in turn affects the morphology of V(2)O(5)/rGO composites. The V(2)O(5)/rGO composites display superior cathode performances with highly reversible specific capacities, good cycling stabilities and excellent rate capabilities (e.g. 102 mA h g(-1) at 19 C). 相似文献
1000.
Branched Chain Fatty Acid Content of United States Retail Cow’s Milk and Implications for Dietary Intake 总被引:1,自引:0,他引:1
Branched chain fatty acids (BCFA) have recently been shown to be a major component of the normal human newborn gastrointestinal
tract and have long been known to be a component of human milk. Ruminant food products are major sources of fat in the American
diet, but there are no studies of milkfat BCFA content in retail milk. We report here the profile and concentrations of BCFA
in a representative sampling of retail milk in the 48 contiguous United States (US), and their estimated intake in the American
diet. Conventionally produced whole fluid milk samples were obtained from 56 processing plants across the contiguous 48 states.
Retail milk samples contain exclusively iso- and anteiso-BCFA with 14–18 carbons. BCFA were 2.05 ± 0.14%, w/w of milkfat fatty acids (mean ± SD), and anteiso-BCFA comprised more than half this total. Based on these data and USDA food availability data, the average per capita BCFA
intake of Americans is estimated to be about 220 mg/d from dairy; if current dietary recommendations were followed, BCFA intake
would be about 400 mg/d. Adding intake from beef consumption, these estimates rise to approximately 400 and 575 mg/d, respectively.
These results indicate that BCFA intake is a substantial fraction of daily fat intake, in amounts exceeding those of many
bioactive fatty acids. 相似文献