全文获取类型
收费全文 | 359篇 |
免费 | 23篇 |
专业分类
电工技术 | 3篇 |
化学工业 | 166篇 |
金属工艺 | 1篇 |
机械仪表 | 9篇 |
建筑科学 | 13篇 |
能源动力 | 6篇 |
轻工业 | 53篇 |
水利工程 | 2篇 |
石油天然气 | 1篇 |
无线电 | 13篇 |
一般工业技术 | 66篇 |
冶金工业 | 19篇 |
自动化技术 | 30篇 |
出版年
2024年 | 1篇 |
2023年 | 9篇 |
2022年 | 53篇 |
2021年 | 45篇 |
2020年 | 10篇 |
2019年 | 13篇 |
2018年 | 11篇 |
2017年 | 15篇 |
2016年 | 11篇 |
2015年 | 7篇 |
2014年 | 20篇 |
2013年 | 9篇 |
2012年 | 24篇 |
2011年 | 21篇 |
2010年 | 20篇 |
2009年 | 17篇 |
2008年 | 14篇 |
2007年 | 12篇 |
2006年 | 13篇 |
2005年 | 7篇 |
2004年 | 7篇 |
2003年 | 4篇 |
2002年 | 5篇 |
2001年 | 3篇 |
2000年 | 3篇 |
1999年 | 4篇 |
1998年 | 6篇 |
1997年 | 4篇 |
1996年 | 4篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1991年 | 2篇 |
1989年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1980年 | 1篇 |
排序方式: 共有382条查询结果,搜索用时 343 毫秒
151.
Tommaso Piccoli Valeria Blandino Laura Maniscalco Domenica Matranga Fabiola Graziano Fabrizio Guajana Luisa Agnello Bruna Lo Sasso Caterina Maria Gambino Rosaria Vincenza Giglio Vincenzo La Bella Marcello Ciaccio Tiziana Colletti 《International journal of molecular sciences》2022,23(18)
Recently, the synaptic proteins neurogranin (Ng) and α-synuclein (α-Syn) have attracted scientific interest as potential biomarkers for synaptic dysfunction in neurodegenerative diseases. In this study, we measured the CSF Ng and α-Syn concentrations in patients affected by AD (n = 69), non-AD neurodegenerative disorders (n-AD = 50) and non-degenerative disorders (n-ND, n = 98). The concentrations of CSF Ng and α-Syn were significantly higher in AD than in n-AD and n-ND. Moreover, the Aβ42/Ng and Aβ42/α-Syn ratios showed statistically significant differences between groups and discriminated AD patients from n-AD patients, better than Ng or α-Syn alone. Regression analyses showed an association of higher Ng concentrations with MMSE < 24, pathological Aβ 42/40 ratios, pTau, tTau and the ApoEε4 genotype. Aβ 42/Ng was associated with MMSE < 24, an AD-related FDG-PET pattern, the ApoEε4 genotype, pathological Aβ 42 levels and Aβ 42/40 ratios, pTau, and tTau. Moreover, APO-Eε4 carriers showed higher Ng concentrations than non-carriers. Our results support the idea that the Aβ 42/Ng ratio is a reliable index of synaptic dysfunction/degeneration able to discriminate AD from other neurological conditions. 相似文献
152.
Alessio Vizzoca Gioia Lucarini Elisabetta Tognoni Selene Tognarelli Leonardo Ricotti Lisa Gherardini Gualtiero Pelosi Mario Pellegrino Arianna Menciassi Settimio Grimaldi Caterina Cinti 《International journal of molecular sciences》2022,23(17)
Over the past few decades, finding more efficient and selective administration routes has gained significant attention due to its crucial role in the bioavailability, absorption rate and pharmacokinetics of therapeutic substances. The pulmonary delivery of drugs has become an attractive target of scientific and biomedical interest in the health care research area, as the lung, thanks to its high permeability and large absorptive surface area and good blood supply, is capable of absorbing pharmaceuticals either for local deposition or for systemic delivery. Nevertheless, the pulmonary drug delivery is relatively complex, and strategies to mitigate the effects of mechanical, chemical and immunological barriers are required. Herein, engineered erythrocytes, the Erythro–Magneto–Hemagglutinin (HA)–virosomes (EMHVs), are used as a novel strategy for efficiently delivering drugs to the lungs. EMHV bio-based carriers exploit the physical properties of magnetic nanoparticles to achieve effective targeting after their intravenous injection thanks to an external magnetic field. In addition, the presence of hemagglutinin fusion proteins on EMHVs’ membrane allows the DDS to anchor and fuse with the target tissue and locally release the therapeutic compound. Our results on the biomechanical and biophysical properties of EMHVs, such as the membrane robustness and deformability and the high magnetic susceptibility, as well as their in vivo biodistribution, highlight that this bio-inspired DDS is a promising platform for the controlled and lung-targeting delivery of drugs, and represents a valuable alternative to inhalation therapy to fulfill unmet clinical needs. 相似文献
153.
Influence of pig genetic type on sensory properties and consumer acceptance of Parma,San Daniele and Toscano dry‐cured hams 下载免费PDF全文
154.
C Seguro F Sau N Zedda O Mura C Montaldo G Scano A Arru MR Leo A Aru A Cherchi 《Canadian Metallurgical Quarterly》1995,40(6):391-397
The antifols, inhibitors of the dihydrofolate reductase (DHFR), such as pyrimethamine and proguanil, have been used against Plasmodium falciparum in the areas where chloroquine resistance is widespread. This use has selected resistant strains in Southeast Asia and South America. The resistance is correlated with point mutations in precise positions of the DHFR gene. A reliable semi-nested PCR diagnosis test was established and used to determine the genotypic features of 29 isolates of P. falciparum originating from Africa. The results obtained by the PCR technique were compared with those of the in vitro drug sensitivity test. Some isolates were found to be polyclonal. Among the mutations tested, only mutations on codon 108 which generate an asparagine induce a decrease in sensitivity to pyrimethamine and cycloguanil, whereas mutation on codon 59 strengthens resistance to both antifols. No mutation on codon 16 or codon 164 was found. 相似文献
155.
A Praline‐Like Flexible Interlayer with Highly Mounted Polysulfide Anchors for Lithium–Sulfur Batteries 下载免费PDF全文
Teng Zhao Yusheng Ye Cheng‐Yen Lao Giorgio Divitini Paul R. Coxon Xiaoyu Peng Xiong He Hyun‐Kyung Kim Kai Xi Caterina Ducati Renjie Chen Yingjun Liu Seeram Ramakrishna Ramachandran Vasant Kumar 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(40)
The development of lithium–sulfur (Li–S) batteries is dogged by the rapid capacity decay arising from polysulfide dissolution and diffusion in organic electrolytes. To solve this critical issue, a praline‐like flexible interlayer consisting of high‐loading titanium oxide (TiO2) nanoparticles and relatively long carbon nanofibers is fabricated. TiO2 nanoparticles with a size gradient occupy both the external and internal of carbon fiber and serve as anchors that allow the chemical adsorption of polysulfides through a conductive nanoarchitecture. The porous conductive carbon backbone helps in the physical absorption of polysulfides and provides redox reaction sites to allow the polysulfides to be reused. More importantly, it offers enough mechanical strength to support a high load TiO2 nanoparticle (79 wt%) that maximizes their chemical role, and can accommodate the large volume changes. Significant enhancement in cycle stability and rate capability is achieved for a readily available sulfur/multi‐walled carbon nanotube composite cathode simply by incorporating this hierarchically nanostructured interlayer. The design and synthesis of interlayers by in situ integration of metal oxides and carbon fibers via a simple route offers the potential to advance Li–S batteries for practical applications in the future. 相似文献
156.
Eberini I Rocco AG Mantegazza M Gianazza E Baroni A Vilardo MC Donghi D Galliano M Beringhelli T 《Journal of molecular graphics & modelling》2008,26(6):1004-1013
Extending a previous investigation, the ability of binding to the model calycin beta-lactoglobulin (BLG) was evaluated both in silico and in vitro for several fluorine-containing (semi-)synthetic molecules of pharmacological and pharmaceutical interest (antibiotics, vastatins, steroid drugs). Simulation procedures included molecular docking according to a Montecarlo-simulated annealing protocol and molecular dynamics; heteronuclear NMR and denaturant gradient gel electrophoresis were the selected experimental techniques. For the tested drugs, ranking of the binding affinity was consistently assessed by computation and by experiment. The affinity for BLG increased in the sequence: 5-fluorosalycilic acid相似文献
157.
Naturally occurring salivary antifungal proteins have been of major interest, due to their potential to provide the basis for peptide antimycotics effective in combating fungal infections in the oral cavity or elsewhere. We tested the fungistatic activity of a number of cationic antifungal proteins, with major emphasis on histatin 5, a basic protein secreted by the human parotid and submandibular glands. Histatin 5 inhibited the growth of Candida albicans and that of other medically important Candida species, such as C. kefyr, C. krusei, and C. parapsilosis, with IC50 values in the range of 10-20 microg/ml. Two Cryptococcus neoformans strains were also sensitive (IC50 5.2 and 5.6 microg/ml). On the other hand, three C. glabrata strains (ATCC 90030, 2001 and 64677) were entirely insensitive to histatin 5 (IC50>225 microg/ml). Four genetically very similar species to C. glabrata, Candida castelli (CBS 4332), Saccharomyces cerevisiae (S288C, BY4741 and CBS 1171), Kluyveromyces delphensis (CBS 2170) and Kluyveromyces bacillisporus (CBS 7720) were all sensitive to histatin 5 (IC50 2.6-64.6 microg/ml). C. glabrata was also insensitive to other members of the histatin family; histatin 1, 3 and P-113 (IC50 values in all cases >225 microg/ml). In addition, two entirely different cationic antifungal proteins originating from frog skin, PGLa and magainin 2, also showed a strong reduced activity toward this fungus. Besides the well-described inherent resistance of C. glabrata to azole-derived antifungal agents, our studies indicate that this species is also able to withstand the otherwise detrimental activities of cationic antifungal proteins. 相似文献
158.
Two‐Color Emitting Colloidal Nanocrystals as Single‐Particle Ratiometric Probes of Intracellular pH 下载免费PDF全文
Francesco Bruni Jacopo Pedrini Caterina Bossio Beatriz Santiago‐Gonzalez Francesco Meinardi Wan Ki Bae Victor I. Klimov Guglielmo Lanzani Sergio Brovelli 《Advanced functional materials》2017,27(12)
Intracellular pH is a key parameter in many biological mechanisms and cell metabolism and is used to detect and monitor cancer formation and brain or heart diseases. pH‐sensing is typically performed by fluorescence microscopy using pH‐responsive dyes. Accuracy is limited by the need for quantifying the absolute emission intensity in living biological samples. An alternative with a higher sensitivity and precision uses probes with a ratiometric response arising from the different pH‐sensitivity of two emission channels of a single emitter. Current ratiometric probes are complex constructs suffering from instability and cross‐readout due to their broad emission spectra. Here, we overcome such limitations using a single‐particle ratiometric pH probe based on dot‐in‐bulk CdSe/CdS nanocrystals (NCs). These nanostructures feature two fully‐separated narrow emissions with different pH sensitivity arising from radiative recombination of core‐ and shell‐localized excitons. The core emission is nearly independent of the pH, whereas the shell luminescence increases in the 3–11 pH range, resulting in a cross‐readout‐free ratiometric response as strong as 600%. In vitro microscopy demonstrates that the ratiometric response in biologic media resembles the precalibralation curve obtained through far‐field titration experiments. The NCs show good biocompatibility, enabling us to monitor in real‐time the pH in living cells. 相似文献
159.
Roberto Piergentili Simona Zaami Anna Franca Cavaliere Fabrizio Signore Giovanni Scambia Alberto Mattei Enrico Marinelli Caterina Gulia Federica Perelli 《International journal of molecular sciences》2021,22(6)
Endometrial cancer (EC) has been classified over the years, for prognostic and therapeutic purposes. In recent years, classification systems have been emerging not only based on EC clinical and pathological characteristics but also on its genetic and epigenetic features. Noncoding RNAs (ncRNAs) are emerging as promising markers in several cancer types, including EC, for which their prognostic value is currently under investigation and will likely integrate the present prognostic tools based on protein coding genes. This review aims to underline the importance of the genetic and epigenetic events in the EC tumorigenesis, by expounding upon the prognostic role of ncRNAs. 相似文献
160.
Ghasem Rashidian Carlo C. Lazado Heba H. Mahboub Ramin Mohammadi-Aloucheh Marko D. Proki Hend S. Nada Caterina Faggio 《International journal of molecular sciences》2021,22(6)
This study was conducted to compare the effects of commercially available (C) and green synthesized (GS) Zinc oxide nanoparticles (ZnO-NPs) on immunological responses of common carp (Cyprinus carpio) skin mucus. GS ZnO-NPs were generated using Thymus pubescent and characterized by UV–vis diffuse reflectance spectroscopy (DRS), Fourier-transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), scanning electron microscope (SEM), and energy-dispersive X-ray spectroscopy (EDX). Fish (n = 150) were randomly allocated into five groups in triplicate and received a waterborne concentration of 0% (control), 25%, and 50% of LC50 96 h of commercially available (C1 and C2) and green synthesized ZnO-NPs (GS1 and GS2) for 21 days. Results from XRD displayed ZnO-NPs with 58 nm in size and UV-vis DRS, EDX, and FT-IR analysis showed that some functional groups from plant extract bonded to the surface of NPs. The SEM images showed that ZnO-NPs have conical morphology. Acute toxicity study showed a higher dose of LC5096h for green synthesized ZnO-NPs (78.9 mg.L−1) compared to the commercial source (59.95 mg.L−1). The highest activity of lysozyme and alternative complement activity (ACH50) were found in control and GS1 groups. A significant decrease in alkaline phosphatase activity (ALP) was found in C1 and C2 groups compared to other treatments. Protease activity (P) was significantly decreased in the C2 group compared to the control and GS groups. Total immunoglobulin (total Ig) content was the highest in the control. In addition, total Ig in the GS1 group was higher than GS2. The exposure to ZnO-NPs lowered total protein content in all experimental groups when compared to control. Present findings revealed lower induced immunosuppressive effects by green synthesized ZnO-NPs on key parameters of fish skin mucus. 相似文献