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71.
Compared the response times (RTs) of 20 process schizophrenics (10 paranoid and 10 nonparanoid) and 20 nonhospitalized controls (mean ages 39.2, 30.0, and 34.1 yrs, respectively) on a hybrid visual and memory search task in which Ss searched displays of up to 15 letters, reporting whether or not displays contained a target, which in different conditions was drawn from a memorized set of 1, 3, or 6 letters. RTs of all groups increased linearly with the product of the number in the memorized target set and the number of displayed letters. Although the intercepts and RTs of the schizophrenics (there were no paranoid–nonparanoid differences) exceeded those of controls, no group differences were found in slopes or in rates of increase in RT as a function of the number of memorized or displayed items. Results are interpreted in terms of a model proposed by W. Schneider and R. M. Shiffrin (1977), which indicates that process schizophrenics are retarded in processes associated with response production but not in a variety of processing stages involved in the comparison of displayed and memorized information. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
72.
Reviews the book, The assessment of aphasia and related disorders (2nd ed.) by Harold Goodglass and Edith Kaplan (1983). The authors state in the preface that much has been learned about aphasia since the first edition of this book was published, through both formal research and clinical experience. Unfortunately, there is little to reflect this in the revised text: The most striking feature of this second edition is the similarity to the original publication. There are a few instances where the text has been rewritten to provide better clarification and to include more recent information. For example, the section in Chapter 2 on "loss of grammar and syntax" has been extended and includes recent references. However, the major portion of each chapter (with the exception of Chapter 3 on the statistical background) is essentially a reproduction of the 1972 text. The extent of this word-for-word reproduction includes the phrase "recent historical papers" to refer to papers published in the 1960s. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
73.
Eight monoclonal antibodies (mAb) recognising barley polypeptides have been identified from a library developed to wheat prolamins. The specificity or the mAb has been determined using enzyme-linked immunosorbent assay (ELISA) and immunoblotting. Six were of broad specificity, recognising D, B, C and γ-hordeins to varying degrees by both techniques. IFRN 0610 preferentially recognised γ-hordeins by ELISA but was highly specific for this hordein group by immunoblotting. Another mAb, IFRN 0624, bound to a Mr ∽ 18000 polypeptide belonging to the CM protein (trypsin/α-amylase inhibitor) family by immunoblotting. This, or a related protein, was detected by 0624 in all hordein fractions using ELISA. These mAb, together with two others described previously and found to recognise the repeat motif of C hordein, were used in ELISA and immunoblot analysis of Octyl-Sepharose fractions of lager foam. Hordein polypeptides were found in all foam fractions, indicating that much foam protein originates from the malt. The CM-like protein was found present in a virtually unmodified form. In contrast, the repeat motif of C hordein was not detected, indicating that it had either been destroyed or masked by other beer constituents. The foam stabilising agent, propylene glycol alginate (PGA), increased the apparent hydrophobicity of hordein fragments suggesting that at least part of the activity of PGA is mediated by interactions with the hordein components of foam.  相似文献   
74.
IgE‐mediated allergy to milk and egg is widespread in industrialised countries and mainly affects infants and young children. It may be connected to an incomplete digestion of dietary proteins causing an inappropriate immune response in the gut. In order to study this, a biochemical model of infant gastroduodenal digestion has been developed, which has reduced levels of protease (eightfold for pepsin and tenfold for trypsin and chymotrypsin), phosphatidylcholine and bile salts, compared with the adult model. This model has been used to study the behaviour of three characterised food‐relevant proteins (bovine β‐lactoglobulin (β‐Lg), β‐casein (β‐CN) and hen's egg ovalbumin), all of which are relevant cows' milk and hens' egg allergens. Digestion products were characterised using electrophoresis, immunochemical techniques and MS. These showed that ovalbumin and β‐CN were digested more slowly using the infant model compared with the adult conditions. Resistant fragments of β‐CN were found in the infant model, which correspond to previously identified IgE epitopes. Surprisingly, β‐Lg was more extensively degraded in the infant model compared with the adult one. This difference was attributed to the tenfold reduction in phosphatidylcholine concentration in the infant model limiting the protective effect of this phospholipid on β‐Lg digestion.  相似文献   
75.
The objective of this study was to determine whether processing could modify the resistance of casein (CN) to digestion in infants. A range of different dairy matrices was manufactured from raw milk in a pilot plant and subjected to in vitro digestion using an infant gut model. Digestion products were identified using MS and immunochemical techniques. Results obtained showed that CNs were able to resist digestion, particularly κ‐ and αs2‐CN. Resistant areas were identified and corresponded to fragments hydrophobic at pH 3.0 (gastric conditions) and/or carrying post‐translational modifications (phosphorylation and glycosylation). Milk processing led to differences in peptide patterns and heat treatment of milk tended to increase the number of peptides found in digested samples. This highlights the likely impact of milk processing on the allergenic potential of CNs.  相似文献   
76.
Glucocorticoids are steroid hormones with key roles in the regulation of many physiological systems including energy homeostasis and immunity. However, chronic glucocorticoid excess, highlighted in Cushing’s syndrome, is established as being associated with increased cardiovascular disease (CVD) risk. Atherosclerosis is the major cause of CVD, leading to complications including coronary artery disease, myocardial infarction and heart failure. While the associations between glucocorticoid excess and increased prevalence of these complications are well established, the mechanisms underlying the role of glucocorticoids in development of atheroma are unclear. This review aims to better understand the importance of glucocorticoids in atherosclerosis and to dissect their cell-specific effects on key processes (e.g., contractility, remodelling and lesion development). Clinical and pre-clinical studies have shown both athero-protective and pro-atherogenic responses to glucocorticoids, effects dependent upon their multifactorial actions. Evidence indicates regulation of glucocorticoid bioavailability at the vasculature is complex, with local delivery, pre-receptor metabolism, and receptor expression contributing to responses linked to vascular remodelling and inflammation. Further investigations are required to clarify the mechanisms through which endogenous, local glucocorticoid action and systemic glucocorticoid treatment promote/inhibit atherosclerosis. This will provide greater insights into the potential benefit of glucocorticoid targeted approaches in the treatment of cardiovascular disease.  相似文献   
77.
In this paper, a new low-frequency predictive current control is proposed for a single-phase cascaded H-bridge multilevel rectifier. The control method has been fully investigated with theoretical analysis, simulation, and experiments on a laboratory prototype with five series-connected H-bridges. However, the analysis and technique are valid for any general level structure. The simulations and experimental results presented demonstrate the excellent performance of the predictive control in terms of AC current waveform quality, power factor, and reduced switching frequency of each bridge, in comparison to traditional control schemes.  相似文献   
78.
79.
Apple (Malus domestica) is the most widely cultivated fruit crop in Europe and frequently causes allergic reactions with a variable degree of severity. So far, four apple allergens Mal d 1, Mal d 2, Mal d 3 and Mal d 4 have been identified. Mal d 1, a Bet v 1 related allergen, and Mal d 4, apple profilin, are sensitive to proteolytic degradation, whereas Mal d 2, a thaumatin-like protein and Mal d 3, a nonspecific lipid transfer protein, are rather stable to proteolytic processes. Mal d 1 and Mal d 4 were purified after expression in Escherichia coli expression system, while Mal d 2 and Mal d 3 were purified from apple fruit tissue. All purified proteins were subjected to detailed physicochemical characterisation to confirm their structural integrity and maintained IgE binding capacity. Detailed investigations of carbohydrate moieties of Mal d 2 demonstrated their involvement in the overall IgE binding capacity of this allergen. It was concluded that the folded structure and IgE binding capacity of all four allergens were preserved during purification.  相似文献   
80.
The geometrical design freedoms associated with additive manufacturing techniques are currently well exploited and finding commercial application. The capability of layer-based processes to allow modification of composition and microstructure in process to achieve functional grading is currently a growing topic. In this work, a method is demonstrated for varying layer thickness within single components that allows part sections to be interlaced for the purpose of locally manipulating material and structural properties. Demonstrator geometries are explored here which exhibit the interfaces within specimens constituted of both 30 µm and 150 µm. Accordingly, a new design freedom for laser powder bed fusion is created.  相似文献   
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