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231.
Jastrzebska M Mróz I Barwiński B Zalewska-Rejdak J Turek A Cwalina B 《Journal of materials science. Materials in medicine》2008,19(1):249-256
Pericardial tissue (bovine or porcine), chemically stabilized with glutaraldehyde (GA), is widely used in cardiovascular surgery
in the form of bioprosthetic valves. GA reacts with tissue proteins and creates inter- and intra-molecular cross-links, resulting
in improved durability. However, tissue calcification and mechanical damage are still unresolved problems. The purpose of
this study was to examine the surface topography of normal human aortic valve and GA-stabilized porcine pericardium tissue
in order to gain comparative insight into supramolecular structure of both tissues. The analysis was focused on morphologic
evaluation of collagen constituents of the tissues. Atomic force microscopy working in the contact mode in air was employed
in the study. Considerable diversity in the spatial orientation of collagen fibrils for the human aortic valve and pericardial
tissue were observed. It was found that different forms of collagen fibril packing, i.e. dense and “in phase” or loose, could
have an impact on the collagen D-banding pattern. Stabilization with GA introduced significant changes in the surface topography
of collagen fibrils and in their spatial organization on the tissue surface. Strong disturbance in the fibril’s D-spacing
was observed. It was also suggested, that the observed structural changes at the supramolecular level might make an important
contribution to the progressive damage and calcification of the tissue. The presented results demonstrate that the AFM method
can be useful for non-destructive structural characterization of heart valves and bioprosthetic heart valve material. 相似文献
232.
Investigations were undertaken to elucidate causes of accelerated low water corrosion (ALWC) of steel piling in a harbour in Southern England. Visual inspection revealed features characteristic of ALWC such as the presence of poorly adherent, thick corrosion products of varying morphology, often seen as large blisters randomly located on sections of the structure at the low water mark. Upon the removal of blisters, a bright surface covered with shallow pits was exposed. Representative samples of the corrosion products were collected from the structure and water and sediment specimens were retrieved from selected areas in the harbour for microbiological, chemical and microscopy testing. In the laboratory, field samples were enriched to detect and enumerate communities of sulphur-oxidising bacteria (SOB) and sulphate-reducing bacteria (SRB). Biofilms, comprising SRB and SOB populations isolated from a sediment sample were grown under static conditions on surfaces of electrodes manufactured from steel piling material. Linear polarisation resistance (LPR) measurements revealed that the corrosion rate of steel with biofilms (0.518 mm y−1) was higher than that recorded in sterile seawater alone (0.054 mm y−1) and in sterile seawater to which nutrient was added (0.218 mm y−1). Scanning electron microscopy (SEM) imaging demonstrated enhanced pitting under biofilms. The results of our investigation revealed for the first time that the attack on steel piling in the presence of sediment SRB and SOB populations was characteristic of ALWC. 相似文献
233.
Within‐person reproducibility and sensitivity to dietary change of C15:0 and C17:0 levels in dried blood spots: Data from the European Food4Me Study 下载免费PDF全文
Viviana Albani Carlos Celis‐Morales Clare B. O'Donovan Marianne C. Walsh Clara Woolhead Hannah Forster Rosalind Fallaize Anna L. Macready Cyril F. M. Marsaux Santiago Navas‐Carretero Rodrigo San‐Cristobal Silvia Kolossa Christina Mavrogianni Christina P. Lambrinou George Moschonis Magdalena Godlewska Agnieszka Surwillo Iwona Traczyk Thomas E. Gundersen Christian A. Drevon Hannelore Daniel Yannis Manios J. Alfredo Martinez Wim H. M. Saris Julie A. Lovegrove Michael J. Gibney Eileen R. Gibney John C. Mathers Ashley J. Adamson Lorraine Brennan 《Molecular nutrition & food research》2017,61(10)
234.
Ceren Eyileten Daniel Jakubik Andleeb Shahzadi Aleksandra Gasecka Edwin van der Pol Salvatore De Rosa Dominika Siwik Magdalena Gajewska Dagmara Mirowska-Guzel Iwona Kurkowska-Jastrzebska Anna Czlonkowska Marek Postula 《International journal of molecular sciences》2022,23(9)
Background: Increased inflammation activates blood coagulation system, higher platelet activation plays a key role in the pathophysiology of ischemic stroke (IS). During platelet activation and aggregation process, platelets may cause increased release of several proinflammatory, and prothrombotic mediators, including microRNAs (miRNAs) and extracellular vesicles (EVs). In the current study we aimed to assess circulating miRNAs profile related to platelet function and inflammation and circulating EVs from platelets, leukocytes, and endothelial cells to analyse their diagnostic and predictive utility in patients with acute IS. Methods: The study population consisted of 28 patients with the diagnosis of the acute IS. The control group consisted of 35 age- and gender-matched patients on acetylsalicylic acid (ASA) therapy without history of stroke and/or TIA with established stable coronary artery disease (CAD) and concomitant cardiovascular risk factors. Venous blood samples were collected from the control group and patients with IS on ASA therapy (a) 24 h after onset of acute IS, (b) 7-days following index hospitalization. Flow cytometry was used to determine the concentration of circulating EVs subtypes (from platelets, leukocytes, and endothelial cells) in platelet-depleted plasma and qRT-PCR was used to determine several circulating plasma miRNAs (miR-19a-3p, miR-186-5p and let-7f). Results: Patients with high platelet reactivity (HPR, based on arachidonic acid-induced platelet aggregometry) had significantly elevated platelet-EVs (CD62+) and leukocyte-EVs (CD45+) concentration compared to patients with normal platelet reactivity at the day of 1 acute-stroke (p = 0.012, p = 0.002, respectively). Diagnostic values of baseline miRNAs and EVs were evaluated with receiver operating characteristic (ROC) curve analysis. The area under the ROC curve for miR-19a-3p was 0.755 (95% CI, 0.63–0.88) p = 0.004, for let-7f, it was 0.874 (95% CI, 0.76–0.99) p = 0.0001; platelet-EVs was 0.776 (95% CI, 0.65–0.90) p = 0.001, whereas for leukocyte-EVs, it was 0.715 (95% CI, 0.57–0.87) p = 0.008. ROC curve showed that pooling the miR-19a-3p expressions, platelet-EVs, and leukocyte-EVs concentration yielded a higher AUC than the value of each individual biomarker as AUC was 0.893 (95% CI, 0.79–0.99). Patients with moderate stroke had significantly elevated miR-19a-3p expression levels compared to patients with minor stroke at the first day of IS. (AUC: 0.867, (95% CI, 0.74–0.10) p = 0.001). Conclusion: Combining different biomarkers of processes underlying IS pathophysiology might be beneficial for early diagnosis of ischemic events. Thus, we believe that in the future circulating biomarkers might be used in the prehospital phase of IS. In particular, circulating plasma EVs and non-coding RNAs including miRNAs are interesting candidates as bearers of circulating biomarkers due to their high stability in the blood and making them highly relevant biomarkers for IS diagnostics. 相似文献
235.
Mateusz Jakubowski Iwona akomska Adriana Kaszuba Andrzej Wojtczak Jerzy Sitkowski Andrzej A. Jarzcki 《International journal of molecular sciences》2022,23(7)
The platinum(II) complexes of general formula [PtCl2(dstp)(S-donor)] were dstp 5,7-dimethyl-1,2,4-triazolo[1,5-a]-pyrimidine (dmtp), 5,7-ditertbutyl-1,2,4-triazolo[1,5-a]pyrimidine (dbtp), 5-methyl-7-isobutyl-1,2,4-triazolo[1,5-a]pyrimidine (ibmtp) or 5,7-diphenyl-1,2,4-triazolo[1,5-a]pyrimidine (dptp), whereas S-tetrahydrothio-phene-1-oxide (TMSO) or diphenyl sulfoxide (DPSO) were synthesized in a one-pot reaction. Here, we present experimental data (1H, 13C, 15N, 195Pt NMR, IR, X-ray) combined with density functional theory (DFT) computations to support and characterize structure–spectra relationships and determine the geometry of dichloride platinum(II) complexes with selected triazolopyrimidines and sulfoxides. Based on the experimental and theoretical data, factors affecting the stability of platinum(II) complexes have been determined. 相似文献
236.
Magdalena Zielińska-Dawidziak Iwona Hertig Dorota Piasecka-Kwiatkowska Halina Staniek Krzysztof W. Nowak Tomasz Twardowski 《Food chemistry》2012
During soya seeds germination in FeSO4 solutions their phytoferritin content is multiplied. Prepared soybean sprouts have been proposed as a safe and easily available source of iron supplementation. The preparation was compared with FeSO4 and ferritin isolates, using rats with induced iron deficiency anaemia. After the end of the 2-week supplementation experiment, it was observed that no statistically significant differences in haemoglobin concentration, mean corpuscular volume, mean corpuscular haemoglobin, and mean corpuscular haemoglobin concentration existed between those animals supplemented with sprouts enriched in ferritin, ferritin isolate and FeSO4 and healthy animals forming the control group. Moreover, the examined preparation had a beneficial influence on the recreation of ferritin reserves in both the liver and the blood serum, and also did not induce negative alterations in general growth parameters of animals. Use of an easily obtainable ferritin iron source may be a profitable alternative in supplementation due to its wide availability and food preservative properties. 相似文献
237.
Igor Buzalewicz Iwona Hoowacz Anna K. Matczuk Mateusz Gu
niczak Dominika Skrzela Magdalena Karwaska Alina Wieliczko Katarzyna Kowal Agnieszka Ulatowska-Jara 《International journal of molecular sciences》2022,23(1)
The worldwide increase in bacterial resistance and healthcare-associated bacterial infections pose a serious threat to human health. The antimicrobial photodynamic method reveals the opportunity for a new therapeutic approach that is based on the limited delivery of photosensitizer from the material surface. Nanoporous inorganic–organic composites were obtained by entrapment of photosensitizer Photolon in polysiloxanes that was prepared by the sol–gel method. The material was characterized by its porosity, optical properties (fluorescence and absorbance), and laser-induced antimicrobial activity against Staphylococcus epidermidis, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. The permanent encapsulation of Photolon in the silica coating and the antimicrobial efficiency was confirmed by confocal microscope and digital holotomography. The generation of free radicals from nanoporous surfaces was proved by scanning Kelvin probe microscopy. For the first time, it was confirmed that Kelvin probe microscopy can be a label-free, noncontact alternative to other conventional methods based on fluorescence or chemiluminescence probes, etc. It was confirmed that the proposed photoactive coating enables the antibacterial photodynamic effect based on free radicals released from the surface of the coating. The highest bactericidal efficiency of the proposed coating was 87.16%. This coating can selectively limit the multiplication of bacterial cells, while protecting the environment and reducing the risk of surface contamination. 相似文献
238.
Kamila Wojas-Krawczyk Iwona Panik Tomasz Kucharczyk Irena Wieleba Natalia Krzyanowska Micha Gil Pawe Krawczyk Janusz Milanowski 《International journal of molecular sciences》2021,22(17)
The efficiency of immunotherapy using monoclonal antibodies that inhibit immune checkpoints has been proven in many clinical studies and well documented by numerous registration approaches. To date, PD-L1 expression on tumor and immune cells, tumor mutation burden (TMB), and microsatellite instability (MSI) are the only validated predictive factors used for the qualification of cancer patients for immunotherapy. However, they are not the ideal predictive factors. No response to immunotherapy could be observed in patients with high PD-L1 expression, TMB, or MSI. On the other hand, the effectiveness of this treatment method also may occur in patients without PD-L1 expression or with low TMB and with microsatellite stability. When considering the best predictive factor, we should remember that the effectiveness of immunotherapy relies on an overly complex process depending on many factors. To specifically stimulate lymphocytes, not only should their activity in the tumor microenvironment be unlocked, but above all, they should recognize tumor antigens. The proper functioning of the anticancer immune system requires the proper interaction of many elements of the specific and non-specific responses. For these reasons, a multi-parameter analysis of the immune system at its different activity levels is considered a very future-oriented predictive marker. Such complex immunological analysis is performed using modern molecular biology techniques. Based on the gene expression studies, we can determine the content of individual immune cells within the tumor, its stroma, and beyond. This includes all cell types from active memory cytotoxic T cells, M1 macrophages, to exhausted T cells, regulatory T cells, and M2 macrophages. In this article, we summarize the possibilities of using an immune system analysis to predict immunotherapy efficacy in cancer patients. Moreover, we present the advantages and disadvantages of immunoprofiling as well as a proposed future direction for this new method of immune system analysis in cancer patients who receive immunotherapy. 相似文献
239.
Consumers of organic spelt food products claim health benefits or sense of well-being from their consumption as opposed to consumption of common wheat products. This study was designed to help clarify the validity of such claims through the evaluation of nutritional properties of starch in a variety of organic spelt products, including breads, biscuits, cookies and muffins, in comparison with their respective common wheat products. Three fermented bread products, namely, yeast leavened, sour and yeast/sour dough were evaluated. Rate and extent of starch digestion were based on the measurement of starch digestion index (SDI) and rapidly available glucose (RAG). The commercial spelt variety used contained approximately eight to ten fold the amount of resistant starch (RS) as compared to common wheat, averaging 3.7% versus 0.4%, and exhibited lower SDI and RAG values. This is the first report to demonstrate high content of RS in spelt. After mixing and fermentation, RS, SDI and RAG reduced, but were still higher in spelt doughs and batters than in those of common wheat. After baking, slight differences were observed in rate and extent of starch digestion between spelt and common wheat baked products. The study showed that differences among baked products were more pronounced than those between spelt and common wheat products. 相似文献
240.