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61.
Prostate cancer is the most common cancer in men worldwide. To improve future drug development and patient management, surrogate biomarkers associated with relevant outcomes are required. Circulating tumour cells (CTCs) are tumour cells that can enter the circulatory system, and are principally responsible for the development of metastasis at distant sites. In recent years, interest in detecting CTCs as a surrogate biomarker has ghiiukjrown. Clinical studies have revealed that high levels of CTCs in the blood correlate with disease progression in patients with prostate cancer; however, their predictive value for monitoring therapeutic response is less clear. Despite the important progress in CTC clinical development, there are critical requirements for the implementation of their analysis as a routine oncology tool. The goal of the present review is to provide an update on the advances in the clinical validation of CTCs as a surrogate biomarker and to discuss the principal obstacles and main challenges to their inclusion in clinical practice.  相似文献   
62.
In this study, the shape memory effect of SMA beams under complex stress conditions is studied by means of a finite element model. The 1D version of a well-established SMA constitutive model is utilized in the numerical computations and the required parameters are obtained experimentally starting from thermal cycling tests in tension under different constant loads. After being calibrated, the model is used to compute the deformation of beams loaded in bending and undergoing thermal cycling; three-point bending and cantilever configurations are considered in this stage. Finally, the response predicted by the model is compared to experimental results and model capabilities are discussed. In particular, insight of the stress and strain evolution in bending is provided.  相似文献   
63.
Twenty-four short-time soaking (STS) processes were carried out to study the influence of some experimental variables (lentil/water ratio, temperature, illumination, elimination of the soaking medium and milling of the seeds) on the glucose, fructose, sucrose, total available soluble sugars, starch, vitamin B1, vitamin B2, available niacin, raffinose, ciceritol, stachyose, total !-galactosides and trypsin inhibitor activities of lentil flours obtained. The soaking process produced, in general, a reduction in the total available soluble sugars content of 8-70%. Glucose was not found in the raw lentils, but was present in the lentil flours obtained after soaking processes carried out in presence of light. Fructose increased in most of the experiments (22-967%) and sucrose decreased significantly (6-73%). Regarding the starch content, the soaking process produced a significant reduction (11-31%). The hydrosoluble vitamin content of lentils, in general, decreased or did not change. However, vitamin B2 and available niacin increased significantly in some experiments, especially in those carried out with ground lentils. The !-galactoside content suffered a large reduction (12-58%) and TIA levels were reduced by 2-33%. From the results obtained, it can be established that STS affects the nutrients and antinutrients of lentils in a different way depending on the experimental conditions. Lentil flours with a low level of antinutritional factors and a high vitamin level are obtained with ground lentils at 42 °C.  相似文献   
64.
The evolution of the nutritive utilization and plasma and muscular content of calcium and phosphorus in rats is studied, as well as the influence that hydrocortisone acetate has (4 mg/100 g weight and day), on them. In pregnant rats injected with saline solution, the retention of calcium is higher on the days 15-18 as a consequence of the increase on the net absorption of the cation. The balance of phosphorus reaches its maximum hight on days 18-21 of gestation, due to the decrease of the urinary excretion during these days. The administration of hydrocortisone acetate to pregnant rats originate a decrease of the net absorption and an increase of the urinary excretion of calcium and phosphorus, which leads to significantly lower balances than those of animals injected with saline solution. The hormone maintains the animals in a negative balance of phosphorus until day 18 of gestation. Besides, it impedes the high retention of calcium which is found with the control pregnant rats on days 15-18. In general, the content in calcium and phosphorus by gram of dry matter of Longissimus dorsi muscle is not modified during gestation. From day 9 of the treatment with hydrocortisone acetate a significant decrease of calcium and phosphorus of the muscle is observed, that in calcium is the more marked the more the treatment is prolonged. This effect seems to be due to the catabolic action of the hormone.  相似文献   
65.
The nutritive utilisation of calcium and magnesium from faba beans (Vicia faba L var major), soaked in different pH solutions and then cooked, was studied in growing rats. Prior to the cooking process the beans were soaked in acid (pH 2.6 and 5.3) or basic (pH 8.4) solutions. Processing of the bean seeds did not produce appreciable losses of Ca or Mg by solubilisation. Digestive utilisation of calcium was high and did not vary with the different processing conditions assayed. Metabolic utilisation of calcium was significantly improved by soaking and by soaking plus cooking. Both digestive and metabolic utilisation of magnesium were significantly improved by all the different processes assayed. The observed improvement in the nutritive utilisation of Ca and Mg was correlated with a higher weight gain of the animals but not with the content of these minerals in the femur and longissimus dorsi muscle. The higher dietary intake of cellulose, lignin and phytate found in the processed faba bean diets did not have a negative effect on the digestive utilisation of the minerals studied. Overall, soaking in basic solution plus cooking was the most effective treatment. The processing conditions studied were inexpensive and easily applied and have great potential for application at household or industry level for human and animal nutrition. Copyright © 2004 Society of Chemical Industry  相似文献   
66.
A systematic study of water absorbency, thermal, and rheological properties was performed on nanocomposite hydrogels of poly(sodium 4-styrene sulfonate) (PSSNa) and poly(2-acrylamide glycolic acid) (PAAG). Montmorillonite was used as clay filler and was previously modified to hydrogel synthesis by addition of (3-acrylamide propyl)trimethylammonium chloride. Syntheses were carried out by in situ radical polymerization, using N,N-methylen-bis-acrylamide as crosslinker reagent. Nanocomposites showed an exfoliated morphology, confirmed by transmission electron microscopy and X-ray diffraction. The water absorption capacity (WAC) of unloaded PSSNa hydrogel was three times higher than for PAAG; due to clay addition, absorption capacity increased for PSSNa nanocomposites and decreased for PAAG. Finally, rheological properties of nanocomposite hydrogels were studied by both dynamic oscillatory test and shear creep analysis. Results showed improvements on mechanical properties, such as yield point, elastic recovery, and storage modulus as consequence of montmorillonite addition.  相似文献   
67.
The effects of α-galactoside removal, using a hydroalcoholic extraction process and phytase supplementation, on the digestive and metabolic utilization of total ash, Mn, Fe, Zn and K from Lupinus albus var. multolupa-based diets by growing rats were evaluated, using a balance technique, and compared to the results obtained using a casein–cystine control diet. The specific amount of minerals needed to complement those provided by the lupin flours and casein in order to reach the target requirements of the growing rat were supplemented as heme or non-heme iron sources or in the form of inorganic salts in the case of Zn or K. The nutritive utilization of total ash, Mn, Fe and Zn was higher from raw and α-galactoside-free lupin flour diets than from the casein–cystine control or the phytase-supplemented diets, whereas smaller differences were found regarding the nutritive utilization of K. Differences in mineral retention were reflected in changes of the mineral contents of some tissues, which varied among the different cations studied.  相似文献   
68.
The effects of the membrane permeant Ca2+ chelator BAPTA-AM on voltage-gated Na+, Ca2+, K+ (I(Na), I(Ca) I(K), respectively) and Ca2+-activated K+ (I(KCa)) currents in cultured bovine chromaffin cells were investigated using the whole-cell patch-clamp technique. Superfusion with BAPTA-AM (50 microM) induced a rapid (< 60 s) and reversible block of both I(KCa) and I(K) (approximately 50%), without affecting either I(Ca) or I(Na). Preincubation with BAPTA-AM (50 microM, 30 min) or cell loading with the nonpermeable active form of BAPTA (10 mM in the pipette solution) permanently blocked I(KCa). BAPTA-AM superfusion (50 microM) also blocked I(K) (approximately 53%) after BAPTA-loading or BAPTA-AM preincubation. In conclusion, we show a fast and reversible block of I(KCa) and I(K) by BAPTA-AM, acting directly on K+ channels before it operates as a Ca2+ chelator, in cultured bovine chromaffin cells.  相似文献   
69.
We have investigated the use of a microwave cavity (Labwell AB, Sweden) to improve the radiochemical yield of 2-[18F]fluoro-2-deoxyglucose (2-[18F]FDG). After characterizing the heating properties of the cavity, three steps of the Hamacher 2-[18F]FDG synthesis which require heating--azeotropic distillation of the target water, nucleophilic substitution, and hydrolysis of the product--were investigated separately. The average radiochemical yield of 2-[18F]FDG for the microwave synthesis, using the phase transfer reagent tetrabutylammonium bicarbonate, was 62 +/- 4% (72 +/- 5%, decay corrected, synthesis time = 31 min).  相似文献   
70.
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