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141.
The effect of catalyst support and preparation method on silver-based catalysts for the direct vapor phase epoxidation of propylene to propylene oxide (PO) was studied. The shape of the CaCO3 support is critical for optimum activity and selectivity of the catalyst. Among the CaCO3 materials investigated as supports, the scalenohedral shape gives the best performance. A simplified method of catalyst preparation (referred to as “slurry method”) was developed. With this method, it is not necessary to dissolve Ag2O into a solution as in the conventional incipient wetness method for preparing silver-based catalysts for propylene and ethylene epoxidation. The key to the slurry method is the addition of a small amount of an effective organic compound, such as ethanolamine, during the formation of the slurry.  相似文献   
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A substantial proportion of subjects with autosomal recessive retinitis pigmentosa (arRP) or Usher syndrome type II (USH2) lacks a genetic diagnosis due to incomplete USH2A screening in the early days of genetic testing. These cases lack eligibility for optimal genetic counseling and future therapy. USH2A defects are the most frequent cause of USH2 and are also causative in individuals with arRP. Therefore, USH2A is an important target for genetic screening. The aim of this study was to assess unscreened or incompletely screened and unexplained USH2 and arRP cases for (likely) pathogenic USH2A variants. Molecular inversion probe (MIP)-based sequencing was performed for the USH2A exons and their flanking regions, as well as published deep-intronic variants. This was done to identify single nucleotide variants (SNVs) and copy number variants (CNVs) in 29 unscreened or partially pre-screened USH2 and 11 partially pre-screened arRP subjects. In 29 out of these 40 cases, two (likely) pathogenic variants were successfully identified. Four of the identified SNVs and one CNV were novel. One previously identified synonymous variant was demonstrated to affect pre-mRNA splicing. In conclusion, genetic diagnoses were obtained for a majority of cases, which confirms that MIP-based sequencing is an effective screening tool for USH2A. Seven unexplained cases were selected for future analysis with whole genome sequencing.  相似文献   
145.
Diabetic nephropathy (DN) is characterized by albuminuria, loss of renal function, renal fibrosis and infiltration of macrophages originating from peripheral monocytes inside kidneys. DN is also associated with intrarenal overactivation of the renin–angiotensin system (RAS), an enzymatic cascade which is expressed and controlled at the cell and/or tissue levels. All members of the RAS are present in the kidneys and most of them are also expressed in monocytes/macrophages. This review focuses on the control of monocyte recruitment and the modulation of macrophage polarization by the RAS in the context of DN. The local RAS favors the adhesion of monocytes on renal endothelial cells and increases the production of monocyte chemotactic protein-1 and of osteopontin in tubular cells, driving monocytes into the kidneys. There, proinflammatory cytokines and the RAS promote the differentiation of macrophages into the M1 proinflammatory phenotype, largely contributing to renal lesions of DN. Finally, resolution of the inflammatory process is associated with a phenotype switch of macrophages into the M2 anti-inflammatory subset, which protects against DN. The pharmacologic interruption of the RAS reduces albuminuria, improves the trajectory of the renal function, decreases macrophage infiltration in the kidneys and promotes the switch of the macrophage phenotype from M1 to M2.  相似文献   
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This paper considers the significance of organic food production in the Netherlands. It critically examines the social and political construction of food markets in the context of the dominance of industrial and corporate retailer‐led food supply chains. Two cases are used to illustrate counter or alternative trends: Frisian Organic Dairy Products (FEZ) and the case of Jan Fokke, a producer converting to organic production. Some key elements of actor‐network theory are developed which focus attention upon the social capabilities and incapacities involved in this transition. The paper highlights some of the inherently strong features of alternative food supply chains and networks, arguing for an expanded definition of ‘organic’ production as a form of social as well as technical organization.  相似文献   
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In this article we describe a demonstrator that shows how the cognitive resource manager (CRM) and the radio-environmental map (REM) can be efficiently implemented in full commercial grade cellular system (i.e., LTE system). The demonstrator shows how the modular CRM together with its open interface, the universal link-layer API (ULLA), facilitates the implementation of efficient radio resource management techniques guaranteeing the quality of service in the LTE system. The CRM, through ULLA, is able to obtain PHY/MAC status information of the link between the tested eNode B and the user equipment, and reconfigure link parameters. This measure-and-control by CRM/ULLA is independent of the underlying radio access technology, which shows the neutrality of CRM/ULLA towards PHY/MAC characteristics. The article also shows how the REM can be easily implemented in such system and how the REM provides the CRM with environmental information that enhances system management performance.  相似文献   
150.

Object

Quantitative assessment of liver fat is highly relevant to preclinical liver research and should ideally be performed non-invasively. This study aimed to compare three non-invasive Magnetic Resonance (MR) and two histopathological methods against the reference standard of biochemically determined liver triglyceride content (LTC).

Materials and methods

A total of 50 mice [21 C57Bl/6OlaHsd mice (C57Bl/6), nine low-density lipoprotein (LDL) receptor knock-out ?/? (LDL ?/?) mice and 20 C57BL/6 mice] received either a high-fat, high-fat-high-cholesterol or control diet, respectively. Mice were examined 4, 8 or 12 weeks into the diet using MR [1H-MR Spectroscopy, Proton Density Fat Fraction (PDFF), mDixon] and histopathological methods (visual scoring or digital image analysis (DIA) of Oil-Red-O (ORO) stained liver sections). Correlations [Pearson’s coefficient (r)] were studied with respect to LTC.

Results

Microvesicular steatosis was seen in 42/50 mice. 1H-MRS values showed normal to moderately elevated liver fat content. Visual scoring and DIA of ORO-sections correlated moderately with LTC at r = 0.59 and r = 0.49 (P < 0.001), respectively. 1H-MRS, PDFF and mDixon correlated significantly better, at r = 0.74, r = 0.75 and r = 0.82, respectively.

Conclusion

Non-invasively determined MR measures of normal to moderately elevated liver fat in mice had a higher correlation with LTC than invasive histopathological measures. Where available, MR is the preferred method for fat quantification.  相似文献   
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