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991.
992.
Nadezhda A. Karaseva Olga V. Farafonova Tatyana N. Ermolaeva 《Food Analytical Methods》2016,9(6):1495-1501
The affinity reaction between the antibodies to okadaic acid immobilized on the sensor’s surface and the toxin in the solution has been investigated. The affinity constant, as well as the association rate constant and the dissociation rate constant, has been calculated. The unlabeled affinity sensor for the detection of okadaic acid has been developed. The calibration plot is linear in the range of concentrations of 5–500 ng mL?1; the limit of detection is 1.4 ng mL?1. The developed sensor can be successfully used for the detection of toxins in real samples. 相似文献
993.
Ana Pozo-Agundo Nerea Villaescusa Jordi Martorell-Marugn Olga Soriano Socorro Leyva Ana Beln Jdar-Reyes Luisa María Botella Pedro Carmona-Sez Francisco Javier Blanco 《International journal of molecular sciences》2021,22(17)
Hereditary hemorrhagic telangiectasia (HHT) is a rare autosomal dominant vascular dysplasia characterized by epistaxis, mucocutaneous telangiectases, and arteriovenous malformations (AVM) in the visceral organs. The diagnosis of HHT is based on clinical Curaçao criteria, which show limited sensitivity in children and young patients. Here, we carried out a liquid biopsy by which we isolated total RNA from plasma exosome samples. A cohort of 15 HHT type 1 patients, 15 HHT type 2 patients, and 10 healthy relatives were analyzed. Upon gene expression data processing and normalization, a statistical analysis was performed to explore similarities in microRNA expression patterns among samples and detect differentially expressed microRNAs between HHT samples and the control group. We found a disease-associated molecular fingerprint of 35 miRNAs over-represented in HHT vs. controls, with eight being specific for HHT1 and 11 for HHT2; we also found 30 under-represented, including nine distinct for HHT1 and nine for HHT2. The analysis of the receiver operating characteristic (ROC) curves showed that eight miRNAs had good (AUC > 75%) or excellent (AUC > 90%) diagnosis value for HHT and even for type HHT1 and HHT2. In addition, we identified the cellular origin of these miRNAs among the cell types involved in the vascular malformations. Interestingly, we found that only some of them were incorporated into exosomes, which suggests a key functional role of these exosomal miRNAs in the pathophysiology of HHT. 相似文献
994.
Evgenii Gerasimov Alexander Erofeev Anastasia Borodinova Anastasia Bolshakova Pavel Balaban Ilya Bezprozvanny Olga L. Vlasova 《International journal of molecular sciences》2021,22(17)
Optogenetics approach is used widely in neurobiology as it allows control of cellular activity with high spatial and temporal resolution. In most studies, optogenetics is used to control neuronal activity. In the present study optogenetics was used to stimulate astrocytes with the aim to modulate neuronal activity. To achieve this goal, light stimulation was applied to astrocytes expressing a version of ChR2 (ionotropic opsin) or Opto-α1AR (metabotropic opsin). Optimal optogenetic stimulation parameters were determined using patch-clamp recordings of hippocampal pyramidal neurons’ spontaneous activity in brain slices as a readout. It was determined that the greatest increase in the number of spontaneous synaptic currents was observed when astrocytes expressing ChR2(H134R) were activated by 5 s of continuous light. For the astrocytes expressing Opto-α1AR, the greatest response was observed in the pulse stimulation mode (T = 1 s, t = 100 ms). It was also observed that activation of the astrocytic Opto-a1AR but not ChR2 results in an increase of the fEPSP slope in hippocampal neurons. Based on these results, we concluded that Opto-a1AR expressed in hippocampal astrocytes provides an opportunity to modulate the long-term synaptic plasticity optogenetically, and may potentially be used to normalize the synaptic transmission and plasticity defects in a variety of neuropathological conditions, including models of Alzheimer’s disease and other neurodegenerative disorders. 相似文献
995.
Svetlana V. Kostyuk Elena V. Proskurnina Elizaveta S. Ershova Larisa V. Kameneva Elena M. Malinovskaya Ekaterina A. Savinova Vasilina A. Sergeeva Pavel E. Umriukhin Olga A. Dolgikh Ekaterina A. Khakina Olga A. Kraevaya Pavel A. Troshin Sergey I. Kutsev Natalia N. Veiko 《International journal of molecular sciences》2021,22(17)
996.
997.
998.
Renate Viebahn-Haensler Olga Sonia Len Fernndez 《International journal of molecular sciences》2021,22(15)
Low-dose ozone acts as a bioregulator in chronic inflammatory diseases, biochemically characterized by high oxidative stress and a blocked regulation. During systemic applications, “Ozone peroxides” are able to replace H2O2 in its specific function of regulation, restore redox signaling, and improve the antioxidant capacity. Two different mechanisms have to be understood. Firstly, there is the direct mechanism, used in topical treatments, mostly via radical reactions. In systemic treatments, the indirect, ionic mechanism is to be discussed: “ozone peroxide” will be directly reduced by the glutathione system, informing the nuclear factors to start the regulation. The GSH/GSSG balance outlines the ozone dose and concentration limiting factor. Antioxidants are regulated, and in the case of inflammatory diseases up-regulated; cytokines are modulated, here downregulated. Rheumatoid arthritis RA as a model for chronic inflammation: RA, in preclinical and clinical trials, reflects the pharmacology of ozone in a typical manner: SOD (superoxide dismutase), CAT (catalase) and finally GSH (reduced glutathione) increase, followed by a significant reduction of oxidative stress. Inflammatory cytokines are downregulated. Accordingly, the clinical status improves. The pharmacological background investigated in a remarkable number of cell experiments, preclinical and clinical trials is well documented and published in internationally peer reviewed journals. This should encourage clinicians to set up clinical trials with chronic inflammatory diseases integrating medical ozone as a complement. 相似文献
999.
Prediction of red wine colour and phenolic parameters from the analysis of its grape extract 总被引:1,自引:0,他引:1
Sandra Fragoso Josep Guasch Laura Aceña Montserrat Mestres Olga Busto 《International Journal of Food Science & Technology》2011,46(12):2569-2575
Herein, the phenolic composition and colour attributes of red grapes extracts (obtained with a fast methodology) were correlated with those of their corresponding wines to predict the final quality properties of wines. The phenolic parameters were evaluated as total phenolic compounds (TPC), total anthocyanins (TA) and total condensed tannins (TCT), whereas the chromatic parameters were evaluated as colour intensity (CI), tonality (To), and the percentages of yellow, red and blue tones. All of them were determined by usual UV–Vis spectrophotometric methods. To get robust models, grapes of five red varieties were collected at three different ripening stages throughout the 2009 vintage. Good correlations between the results from grapes and wines were obtained, showing high regression coefficients and low prediction errors for TPC (R2 = 0.929, RMSE = 5.99%), TA (R2 = 0.953, RMSE = 7.23%) and CI (R2 = 0.954, RMSE = 7.58), concluding that these wine phenolic properties can be predicted reliably from the extracts obtained with an optimised fast extraction method from grapes on the ripening controls along the maturity process. 相似文献
1000.
Olga V. Masalova Ekaterina I. Lesnova Regina R. Klimova Alexander V. Ivanov Alla A. Kushch 《International journal of molecular sciences》2021,22(15)
Despite extensive research, there is still no vaccine against the hepatitis C virus (HCV). The aim of this study was to investigate whether MSCs can exhibit adjuvant properties during DNA vaccination against hepatitis C. We used the pcNS3-NS5B plasmid encoding five nonstructural HCV proteins and MSCs derived from mice bone marrow. Five groups of DBA mice were immunized with the plasmid and/or MSCs in a different order. Group 1 was injected with the plasmid twice at intervals of 3 weeks; Group 2 with the plasmid, and after 24 h with MSCs; Group 3 with MSCs followed by the plasmid the next day; Group 4 with only MSCs; and Group 5 with saline. When the MSCs were injected prior to DNA immunization, the cell immune response to HCV proteins assessed by the level of IFN-γ synthesis was markedly increased compared to DNA alone. In contrast, MSCs injected after DNA suppressed the immune response. Apparently, the high level of proinflammatory cytokines detected after DNA injection promotes the conversion of MSCs introduced later into the immunosuppressive MSC2. The low level of cytokines in mice before MSC administration promotes the high immunostimulatory activity of MSC1 in response to a DNA vaccine. Thus, when administered before DNA, MSCs are capable of exhibiting promising adjuvant properties. 相似文献