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141.
Aydin Atakan Beyza Macunluoglu Yuksel Kaya Elif Ari Halit Demir Ebru Asicioglu Cigdem Kaspar 《Hemodialysis international. International Symposium on Home Hemodialysis》2014,18(1):62-69
Cardiovascular disease (CVD) is the main cause of mortality in hemodialysis (HD) patients. Epicardial fat tissue (EFT) is a new risk factor in CVD. The aim of this study was to evaluate the association between EFT and coronary artery flow reserve (CFR), which is an early indicator of endothelial dysfunction in coronary vessels of HD patients. We performed a cross‐sectional study including 71 chronic HD patients and 65 age‐ and sex‐matched healthy controls. Epicardial fat tissue was significantly higher in HD patients when compared to healthy controls (6.53 ± 1.01 mm vs. 5.79 ± 1.06 mm, respectively, P < 0.001). On transthoracic Doppler echocardiography, CFR values were significantly lower in HD patients when compared to healthy controls (1.73 ± 0.11 vs. 2.32 ± 0.28, P < 0.001). Correlation analysis showed CFR values to be inversely correlated with EFT (r = ?0.287, P < 0.05). Multiple linear regression analysis was used to define independent determinants of EFT in HD patients. Artery flow reserve, age, body mass index and total cholesterol levels were independently correlated with EFT thickness. This study demonstrated that EFT was significantly higher among HD patients compared to healthy controls. In addition, this study was the first to demonstrate an inverse correlation between EFT and CFR in this patient population. 相似文献
142.
Si:As blocked impurity band detectors have been partially deprocessed and measured by Fourier transform spectroscopy to determine their transmittance and reflectance at cryogenic temperatures over the wavelength range 2 μm to 40 μm. A method is presented by which the propagation constants can be extracted from an inversion of the transmittance and reflectance data. The effective propagation constants for the active layer from 2 μm to 20 μm were calculated as well as the absorption cross section of arsenic in silicon, which agrees well with previous results from the literature. The infrared absorptance of the full detector was determined, and the analytical method also provides an estimate of absorption in the active layer alone. Infrared absorptance of the active layer is compared to the quantum yield measured by photoelectric means on similar detectors. The optical methods outlined here, in conjunction with standard electronic measurements, could be used to predict the performance of such detectors from measurements of the blanket films from which they are to be fabricated. 相似文献
143.
Rebecca S. Hayden Jean‐Philippe Fortin Benjamin Harwood Balajikarthick Subramanian Kyle P. Quinn Irene Georgakoudi Alan S. Kopin David L. Kaplan 《Advanced functional materials》2014,24(4):472-479
The goals of the present study are to establish an in vitro co‐culture model of osteoblast and osteoclast function and to quantify the resulting bone remodeling. The bone is tissue engineered using well‐defined silk protein biomaterials in 2D and 3D formats in combination with human cells. Parathyroid hormone (PTH) and glucose‐dependent insulinotropic peptide (GIP) are selected because of their roles in bone remodeling for expression in tethered format on human mesenchymal stem cells (hMSCs). The cell‐modified biomaterial surfaces are reconstructed from scanning electron microscopy images into 3D models for quantitative measurement of surface characteristics. Increased calcium deposition and surface roughness are found in 3D surface models of silk protein films remodeled by co‐cultures containing tethered PTH, and decreased surface roughness is found for the films remodeled by tethered GIP co‐cultures. Increased surface roughness is not found in monocultures of hMSCs expressing tethered PTH, suggesting that osteoclast‐osteoblast interactions in the presence of PTH signaling are responsible for the increased mineralization. These data point towards the design of in vitro bone models in which osteoblast‐osteoclast interactions are mimicked for a better understanding of bone remodeling. 相似文献
144.
145.
The nuclear data on (α, xn) reactions are very important in the fields of radiation shielding, long-term safe handling of spent fuel and spallation neutron-production. In this study, neutron-production cross sections have been calculated for some target nuclei such as 65Cu and 209Bi. Hybrid model and geometry dependent hybrid model have been used to calculate the pre-equilibrium neutron-production cross sections. The mean free path parameter’s effect for (α, xn) neutron-production cross section has been examined. The obtained results have been discussed and compared with the available experimental data. 相似文献
146.
147.
Lesonsky Elaine M.; Kaplan Marvin L.; Kaplan Netta R. 《Canadian Metallurgical Quarterly》1986,23(1):41
Developed a coding system to operationalize the Gestalt therapy formulation of experiential organization and used the scale to test the assumption that each member of an interacting couple is influenced by concurrent organization of experience processes of the other. 20 couples (at least 1 member was an undergraduate student) who had lived together for at least 6 mo were rated. Findings support the reliability of the procedure, but data do not reflect adequate levels of usage along the full range of the scale. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
148.
149.
PA Hollander SC Elbein IB Hirsch D Kelley J McGill T Taylor SR Weiss SE Crockett RA Kaplan J Comstock CP Lucas PA Lodewick W Canovatchel J Chung J Hauptman 《Canadian Metallurgical Quarterly》1998,21(8):1288-1294
OBJECTIVE: Obesity is an important risk factor for type 2 diabetes. Weight loss in patients with type 2 diabetes is associated with improved glycemic control and reduced cardiovascular disease risk factors, but weight loss is notably difficult to achieve and sustain with caloric restriction and exercise. The purpose of this study was to assess the impact of treatment with orlistat, a pancreatic lipase inhibitor, on weight loss, glycemic control, and serum lipid levels in obese patients with type 2 diabetes on sulfonylurea medications. RESEARCH DESIGN AND METHODS: In a multicenter 57-week randomized double-blind placebo-controlled study, 120 mg orlistat or placebo was administered orally three times a day with a mildly hypocaloric diet to 391 obese men and women with type 2 diabetes who were aged > 18 years, had a BMI of 28-40 kg/m2, and were clinically stable on oral sulfonylureas. Changes in body weight, glycemic control, lipid levels, and drug tolerability were measured. RESULTS: After 1 year of treatment, the orlistat group lost 6.2 +/- 0.45% (mean +/- SEM) of initial body weight vs. 4.3 +/- 0.49% in the placebo group (P < 0.001). Twice as many patients receiving orlistat (49 vs. 23%) lost > or = 5% of initial body weight (P < 0.001). Orlistat treatment plus diet compared with placebo plus diet was associated with significant improvement in glycemic control, as reflected in decreases in HbA1c (P < 0.001) and fasting plasma glucose (P < 0.001) and in dosage reductions of oral sulfonylurea medication (P < 0.01). Orlistat therapy also resulted in significantly greater improvements than placebo in several lipid parameters, namely, greater reductions in total cholesterol, (P < 0.001), LDL cholesterol (P < 0.001), triglycerides (P < 0.05), apolipoprotein B (P < 0.001), and the LDL-to-HDL cholesterol ratio (P < 0.001). Mild to moderate and transient gastrointestinal events were reported with orlistat therapy, although their association with study withdrawal was low. Fat-soluble vitamin levels generally remained within the reference range, and vitamin supplementation was required in only a few patients. CONCLUSIONS: Orlistat is an effective treatment modality in obese patients with type 2 diabetes with respect to clinically meaningful weight loss and maintenance of weight loss, improved glycemic control, and improved lipid profile. 相似文献
150.
It was recently predicted by us that cyclotron resonance of free electrons in vacuum and conduction electrons in semiconductors may exhibit bistable and hysteretic behavior which is due to the relativistic mass-effect (or pseudo relativistic-in semiconductors). Consistent with this prediction, the hysteretic cyclotron resonance of a trapped single electron in vacuum has recently been experimentally observed by Gabrielse et al. A preliminary estimate shows that their experimental results are consistent with the relativistic nature of the observed hysteresis. In this paper we consider this phenomenon as ultimate bistability since it is based on the most fundamental mechanism of nonlinearity (the relativistic mass-effect), involves the interaction of an EM wave with the simplest single elementary particle, and exhibits the first known intrinsic bistability with no macroscopic optical feedback. We also show that a hysteretic resonance of a Single electron based on relativistic effects is feasible also in a parabolic potential (with no magnetic field required to attain a resonance). 相似文献