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991.
This paper describes a decision cache for the eXtensible Access Control Markup Language (XACML) that supports fine-grained authorisation and anonymisation of XML based messages and documents down to XML attribute and element level. The decision cache is implemented as an XACML obligation service, where a specification of the XML elements to be authorised and anonymised is sent to the Policy Enforcement Point (PEP) during initial authorisation. Further authorisation of individual XML elements according to the authorisation specification is then performed on all matching XML resources, and decisions are stored in the decision cache. This makes it possible to cache fine-grained XACML authorisation and anonymisation decisions, which reduces the authorisation load on the Policy Decision Point (PDP). The theoretical solution is related to a practical case study consisting of a privacy-enhanced intrusion detection system that needs to perform anonymisation of Intrusion Detection Message Exchange Format (IDMEF) XML messages before they are sent to a security operations centre that operates in privacy-preserving mode. The solution increases the scalability of XACML based authorisation significantly, and may be instrumental in implementing federated authorisation and anonymisation based on XACML in several areas, including intrusion detection systems, web services, content management systems and GRID based authentication and authorisation. 相似文献
992.
Rayna Bryaskova Nikoleta Philipova Nikolay Georgiev Ivo Lalov Vladimir Bojinov Christophe Detrembleur 《应用聚合物科学杂志》2021,138(31):50769
In this article we report on the facile preparation of photoactive antibacterial mussel inspired polymer coatings deposited on a stainless steel (SS) substrate from water based precursors. The coating is prepared by the sequential deposition of aqueous based solutions of an anchoring layer based on bio-inspired glue, a cationic polymer bearing pendent catechols, a nanogel decorated by ortho-quinones and a photosensitizer of the aminoacridine type. This latter is grafted to the coating by reaction of its amino group with the o-quinone of the deposited nanogel. The deposition of all layers is followed in-line by Quartz crystal microbalance coupled with dissipation (QCM-D) and AFM shows that the thin polymer film repeated the roughness of the SS substrate. The prepared coatings show good mechanical properties applying nanoindentation techniques. The established antibacterial activity of the prepared photoactive polymer coatings on SS against Gram-negative E. coli strain demonstrate their potential as a power tool for medical applications. 相似文献
993.
Maria D. Dmitrieva Anna A. Voitova Maya A. Dymova Vladimir A. Richter Elena V. Kuligina 《International journal of molecular sciences》2021,22(1)
Background: The combination of the unique properties of cancer cells makes it possible to find specific ligands that interact directly with the tumor, and to conduct targeted tumor therapy. Phage display is one of the most common methods for searching for specific ligands. Bacteriophages display peptides, and the peptides themselves can be used as targeting molecules for the delivery of diagnostic and therapeutic agents. Phage display can be performed both in vitro and in vivo. Moreover, it is possible to carry out the phage display on cells pre-enriched for a certain tumor marker, for example, CD44 and CD133. Methods: For this work we used several methods, such as phage display, sequencing, cell sorting, immunocytochemistry, phage titration. Results: We performed phage display using different screening systems (in vitro and in vivo), different phage libraries (Ph.D-7, Ph.D-12, Ph.D-C7C) on CD44+/CD133+ and without enrichment U-87 MG cells. The binding efficiency of bacteriophages displayed tumor-targeting peptides on U-87 MG cells was compared in vitro. We also conducted a comparative analysis in vivo of the specificity of the accumulation of selected bacteriophages in the tumor and in the control organs (liver, brain, kidney and lungs). Conclusions: The screening in vivo of linear phage peptide libraries for glioblastoma was the most effective strategy for obtaining tumor-targeting peptides providing targeted delivery of diagnostic and therapeutic agents to glioblastoma. 相似文献
994.
Evdokia Bogdanova Olga Beresneva Olga Galkina Irina Zubina Galina Ivanova Marina Parastaeva Natalia Semenova Vladimir Dobronravov 《International journal of molecular sciences》2021,22(9)
Background: Arterial hypertension (AH) is associated with heart and chronic kidney disease (CKD). However, the precise mechanisms of myocardial remodeling (MR) in the settings of CKD remain elusive. We hypothesized that TRPC6, calcineurin/NFAT, and Wnt/β-catenin signaling pathways are involved in the development of MR in the background of CKD and AH. Methods: Early CKD was induced by performing a 5/6 nephrectomy (5/6NE) in spontaneously hypertensive rats (SHR-NE). Sham-operated (SO) SHR (SHR-SO) and Wistar Kyoto (WKY-SO) rats served as controls. Systolic blood pressure (SBP), heart rate, myocardial mass index (MMI), serum creatinine, cardiomyocyte diameter (dCM), myocardial fibrosis (MF), serum and kidney α-Klotho levels, myocardial expression of calcineurin (CaN), TRPC6, and β-catenin were measured two months after 5/6NE or SO. Results: NE-induced kidney dysfunction corresponded to mild-to-moderate human CKD and was associated with an increase in FGF23 and a decrease in renal α-Klotho. The levels of SBP, MMI, dCM, and MF were higher in SHRs compared to WKY-SO as well as in SHR-NE vs. SHR-SO. The MR was associated with increased cardiomyocyte expression of CaN/NFAT and β-catenin along with its intracellular re-distribution. TRPC6 protein levels were substantially elevated in both SHR groups with higher Trpc6 mRNA expression in SHR-NE. Conclusions: The Wnt/β-catenin and TRPC6/CaN/NFAT hypertrophic signaling pathways seem to be involved in myocardial remodeling in the settings of AH and CKD and might be mediated by FGF23 and α-Klotho axis. 相似文献
995.
Dr. Sachin B. Wagh Dr. Vladimir A. Maslivetc Dr. James J. La Clair Prof. Dr. Alexander Kornienko 《Chembiochem : a European journal of chemical biology》2021,22(22):3109-3139
Fluorescent probes have gained profound use in biotechnology, drug discovery, medical diagnostics, molecular and cell biology. The development of methods for the translation of fluorophores into fluorescent probes continues to be a robust field for medicinal chemists and chemical biologists, alike. Access to new experimental designs has enabled molecular diversification and led to the identification of new approaches to probe discovery. This review provides a synopsis of the recent lessons in modern fluorescent probe discovery. 相似文献
996.
Transmutation of radioactive nuclides into stable or short-lived ones has been under discussion as a measure to deal with the wastes of nuclear technology since its very beginning. There has been a lot of research activities world-wide with various approaches to transmuter design, matrix for waste incorporation and end waste form. This diversity comes from differently formulated transmutation priorities which, in their turn, originated in differently formulated strategy for development of nuclear fuel cycles. The present paper aims at surveying the goals of waste transmutation in view of trends identified in the past decade and address some new characteristics for estimating its radiological cost. 相似文献
997.
Freeze–thaw treatment of low‐concentrated (<C*) aqueous solutions of poly(vinyl alcohol) (PVA) results in the formation of a cryoprecipitate fraction. It is shown that the efficiency of such a process (the yield of PVA cryoprecipitation) depends on the initial polymer concentration in the solution to be frozen and the conditions of a cryogenic influence. The key factor is defrostation dynamics: The slower the thawing rate, the higher the cryoprecipitation yield. The iodine‐staining method is employed for the quantitative analysis of PVA concentrations in the solutions under study and the necessity of the use of reduced (0–2°C) temperatures throughout such a PVA quantification is demonstrated. Observation of the kinetics of the freeze–thaw‐induced formation of cryoprecipitate matter reveals the extreme character of the temperature dependence of the efficacy of PVA macromolecule aggregation, the extreme point being situated in the vicinity of −2°C. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 1978–1986, 1999 相似文献
998.
Claire Albasi J. Pierre Riba Ivana Sokolovska Vladimir Bales 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1997,69(3):329-336
The results of a study of the enzymatic hydrolysis of sunflower oil are presented. The influence of the enzyme and substrate concentrations has been investigated. The interfacial area was modified by changing the volume fraction of oil, while keeping other variables constant. A phase inversion is indicated, which influenced the reaction kinetics by the possible formation of enzyme multilayers, because of steric hindrance. By means of the initial hydrolysis rate, the lipase concentration for achieving interface saturation was estimated. A Lewis cell type contactor was used for the determination of the interface surface, and droplet diameters were deduced. © 1997 SCI. 相似文献
999.
Zaira Gadzhimagomedova Vladimir Polyakov Ilia Pankin Vera Butova Daria Kirsanova Mikhail Soldatov Darya Khodakova Anna Goncharova Elizaveta Mukhanova Anna Belanova Aleksey Maksimov Alexander Soldatov 《International journal of molecular sciences》2021,22(23)
X-ray photodynamic therapy (XPDT) has been recently considered as an efficient alternative to conventional radiotherapy of malignant tissues. Nanocomposites for XPDT typically consist of two components—a nanophosphor which re-emits X-rays into visible light that in turn is absorbed by the second component, a photosensitizer, for further generation of reactive oxygen species. In this study, BaGdF5 nanophosphors doped with different Eu:Gd ratios in the range from 0.01 to 0.50 were synthesized by the microwave route. According to transmission electron microscopy (TEM), the average size of nanophosphors was ~12 nm. Furthermore, different coatings with amorphous SiO2 and citrates were systematically studied. Micro-CT imaging demonstrated superior X-ray attenuation and sufficient contrast in the liver and the spleen after intravenous injection of citric acid-coated nanoparticles. In case of the SiO2 surface, post-treatment core–shell morphology was verified via TEM and the possibility of tunable shell size was reported. Nitrogen adsorption/desorption analysis revealed mesoporous SiO2 formation characterized by the slit-shaped type of pores that should be accessible for methylene blue photosensitizer molecules. It was shown that SiO2 coating subsequently facilitates methylene blue conjugation and results in the formation of the BaGdF5: 10% Eu3+@SiO2@MB nanocomposite as a promising candidate for application in XPDT. 相似文献
1000.
Carolina Pinto Diana Sousa Vladimir Ghilas Andrea Dardis Maurizio Scarpa Maria Fatima Macedo 《International journal of molecular sciences》2021,22(23)
Acid sphingomyelinase deficiency (ASMD) is a lysosomal storage disease caused by deficient activity of acid sphingomyelinase (ASM) enzyme, leading to the accumulation of varying degrees of sphingomyelin. Lipid storage leads to foam cell infiltration in tissues, and clinical features including hepatosplenomegaly, pulmonary insufficiency and in some cases central nervous system involvement. ASM enzyme replacement therapy is currently in clinical trial being the first treatment addressing the underlying pathology of the disease. Therefore, presently, it is critical to better comprehend ASMD to improve its diagnose and monitoring. Lung disease, including recurrent pulmonary infections, are common in ASMD patients. Along with lung disease, several immune system alterations have been described both in patients and in ASMD animal models, thus highlighting the role of ASM enzyme in the immune system. In this review, we summarized the pivotal roles of ASM in several immune system cells namely on macrophages, Natural Killer (NK) cells, NKT cells, B cells and T cells. In addition, an overview of diagnose, monitoring and treatment of ASMD is provided highlighting the new enzyme replacement therapy available. 相似文献