全文获取类型
收费全文 | 10528篇 |
免费 | 560篇 |
国内免费 | 10篇 |
专业分类
电工技术 | 132篇 |
综合类 | 6篇 |
化学工业 | 2765篇 |
金属工艺 | 177篇 |
机械仪表 | 344篇 |
建筑科学 | 383篇 |
矿业工程 | 24篇 |
能源动力 | 449篇 |
轻工业 | 2073篇 |
水利工程 | 131篇 |
石油天然气 | 57篇 |
武器工业 | 2篇 |
无线电 | 518篇 |
一般工业技术 | 1461篇 |
冶金工业 | 997篇 |
原子能技术 | 76篇 |
自动化技术 | 1503篇 |
出版年
2024年 | 35篇 |
2023年 | 96篇 |
2022年 | 407篇 |
2021年 | 479篇 |
2020年 | 296篇 |
2019年 | 320篇 |
2018年 | 379篇 |
2017年 | 435篇 |
2016年 | 437篇 |
2015年 | 311篇 |
2014年 | 410篇 |
2013年 | 822篇 |
2012年 | 708篇 |
2011年 | 808篇 |
2010年 | 557篇 |
2009年 | 568篇 |
2008年 | 511篇 |
2007年 | 435篇 |
2006年 | 359篇 |
2005年 | 256篇 |
2004年 | 225篇 |
2003年 | 212篇 |
2002年 | 184篇 |
2001年 | 136篇 |
2000年 | 120篇 |
1999年 | 117篇 |
1998年 | 362篇 |
1997年 | 245篇 |
1996年 | 167篇 |
1995年 | 117篇 |
1994年 | 78篇 |
1993年 | 73篇 |
1992年 | 37篇 |
1991年 | 31篇 |
1990年 | 25篇 |
1989年 | 28篇 |
1988年 | 31篇 |
1987年 | 15篇 |
1986年 | 23篇 |
1985年 | 24篇 |
1984年 | 27篇 |
1983年 | 27篇 |
1982年 | 18篇 |
1981年 | 19篇 |
1980年 | 23篇 |
1979年 | 12篇 |
1978年 | 9篇 |
1977年 | 17篇 |
1976年 | 33篇 |
1975年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Aleksandra Obuchowska Kamila Gorczyca Arkadiusz Standyo Karolina Obuchowska aneta Kimber-Trojnar Magdalena Wierzchowska-Opoka Boena Leszczyska-Gorzelak 《International journal of molecular sciences》2022,23(15)
Probiotics are live microorganisms that induce health benefits in the host. Taking probiotics is generally safe and well tolerated by pregnant women and their children. Consumption of probiotics can result in both prophylactic and therapeutic effects. In healthy adult humans, the gut microbiome is stable at the level of the dominant taxa: Bacteroidetes, Firmicutes and Actinobacteria, and has a higher presence of Verrucomicrobia. During pregnancy, an increase in the number of Proteobacteria and Actinobacteria phyla and a decrease in the beneficial species Roseburia intestinalis and Faecalibacterium prausnitzii are observed. Pregnancy is a “window” to the mother’s future health. The aim of this paper is to review studies assessing the potentially beneficial effects of probiotics in preventing the development of diseases that appear during pregnancy, which are currently considered as risk factors for the development of metabolic syndrome, and consequently, reducing the risk of developing maternal metabolic syndrome in the future. The use of probiotics in gestational diabetes mellitus, preeclampsia and excessive gestational weight gain is reviewed. Probiotics are a relatively new intervention that can prevent the development of these disorders during pregnancy, and thus, would reduce the risk of metabolic syndrome resulting from these disorders in the mother’s future. 相似文献
42.
43.
Karina Gonzlez-García Armando Lpez-Martínez Juan Manuel Velzquez-Enríquez Cecilia Zertuche-Martínez Gabriela Carrasco-Torres Luis Manuel Snchez-Navarro Saúl Villa-Trevio Rafael Baltirrez-Hoyos Vernica Rocío Vsquez-Garzn 《International journal of molecular sciences》2022,23(14)
Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease characterized by parenchymal scarring, leading progressively to alveolar architecture distortion, respiratory failure, and eventually death. Currently, there is no effective treatment for IPF. Previously, 3′5-dimaleamylbenzoic acid (3′5-DMBA), a maleimide, demonstrated pro-apoptotic, anti-inflammatory, and anti-cancer properties; however, its potential therapeutic effects on IPF have not been addressed. Bleomycin (BLM) 100 U/kg was administered to CD1 mice through an osmotic minipump. After fourteen days of BLM administration, 3′5-DMBA (6 mg/kg or 10 mg/kg) and its vehicle carboxymethylcellulose (CMC) were administered intragastrically every two days until day 26. On day 28, all mice were euthanized. The 3′5-DMBA effect was assessed by histological and immunohistochemical staining, as well as by RT-qPCR. The redox status on lung tissue was evaluated by determining the glutathione content and the GSH/GSSG ratio. 3′5-DMBA treatment re-established typical lung histological features and decreased the expression of BLM-induced fibrotic markers: collagen, α-SMA, and TGF-β1. Furthermore, 3′5-DMBA significantly reduced the expression of genes involved in fibrogenesis. In addition, it decreased reduced glutathione and increased oxidized glutathione content without promoting oxidative damage to lipids, as evidenced by the decrease in the lipid peroxidation marker 4-HNE. Therefore, 3′5-DMBA may be a promising candidate for IPF treatment. 相似文献
44.
Benedetta Mattorre Silvana Caristi Simona Donato Emilia Volpe Marika Faiella Alessandro Paiardini Rosa Sorrentino Fabiana Paladini 《International journal of molecular sciences》2022,23(9)
The M1 zinc metalloproteases ERAP1, ERAP2, and IRAP play a role in HLA-I antigen presentation by refining the peptidome either in the ER (ERAP1 and ERAP2) or in the endosomes (IRAP). They have also been entrusted with other, although less defined, functions such as the regulation of the angiotensin system and blood pressure. In humans, ERAP1 and IRAP are commonly expressed. ERAP2 instead has evolved under balancing selection that maintains two haplotypes, one of which undergoing RNA splicing leading to nonsense-mediated decay and loss of protein. Hence, likewise in rodents, wherein the ERAP2 gene is missing, about a quarter of the human population does not express ERAP2. We report here that macrophages, but not monocytes or other mononuclear blood cells, express and secrete an ERAP2 shorter form independent of the haplotype. The generation of this “short” ERAP2 is due to an autocatalytic cleavage within a distinctive structural motif and requires an acidic micro-environment. Remarkably, ERAP2 “short” binds IRAP and the two molecules are co-expressed in the endosomes as well as in the cell membrane. Of note, the same phenomenon could be observed in some cancer cells. These data prompt us to reconsider the role of ERAP2, which might have been maintained in humans due to fulfilling a relevant function in its “short” form. 相似文献
45.
Claudia Riccardi Federica DAria Filomena Anna Digilio Maria Rosaria Carillo Jussara Amato Dominga Fasano Laura De Rosa Simona Paladino Mariarosa Anna Beatrice Melone Daniela Montesarchio Concetta Giancola 《International journal of molecular sciences》2022,23(9)
A set of guanine-rich aptamers able to preferentially recognize full-length huntingtin with an expanded polyglutamine tract has been recently identified, showing high efficacy in modulating the functions of the mutated protein in a variety of cell experiments. We here report a detailed biophysical characterization of the best aptamer in the series, named MS3, proved to adopt a stable, parallel G-quadruplex structure and show high nuclease resistance in serum. Confocal microscopy experiments on HeLa and SH-SY5Y cells, as models of non-neuronal and neuronal cells, respectively, showed a rapid, dose-dependent uptake of fluorescein-labelled MS3, demonstrating its effective internalization, even in the absence of transfecting agents, with no general cytotoxicity. Then, using a well-established Drosophila melanogaster model for Huntington’s disease, which expresses the mutated form of human huntingtin, a significant improvement in the motor neuronal function in flies fed with MS3 was observed, proving the in vivo efficacy of this aptamer. 相似文献
46.
47.
Joo E. Rodrigues Ana Martinho Catia Santa Nuno Madeira Manuel Coroa Vítor Santos Maria J. Martins Carlos N. Pato Antonio Macedo Bruno Manadas 《International journal of molecular sciences》2022,23(9)
Mass spectrometry (MS)-based techniques can be a powerful tool to identify neuropsychiatric disorder biomarkers, improving prediction and diagnosis ability. Here, we evaluate the efficacy of MS proteomics applied to human peripheral fluids of schizophrenia (SCZ) patients to identify disease biomarkers and relevant networks of biological pathways. Following PRISMA guidelines, a search was performed for studies that used MS proteomics approaches to identify proteomic differences between SCZ patients and healthy control groups (PROSPERO database: CRD42021274183). Nineteen articles fulfilled the inclusion criteria, allowing the identification of 217 differentially expressed proteins. Gene ontology analysis identified lipid metabolism, complement and coagulation cascades, and immune response as the main enriched biological pathways. Meta-analysis results suggest the upregulation of FCN3 and downregulation of APO1, APOA2, APOC1, and APOC3 in SCZ patients. Despite the proven ability of MS proteomics to characterize SCZ, several confounding factors contribute to the heterogeneity of the findings. In the future, we encourage the scientific community to perform studies with more extensive sampling and validation cohorts, integrating omics with bioinformatics tools to provide additional comprehension of differentially expressed proteins. The produced information could harbor potential proteomic biomarkers of SCZ, contributing to individualized prognosis and stratification strategies, besides aiding in the differential diagnosis. 相似文献
48.
Emilly Sigoli Rosangela Aline Anto Maria Paula Guerreiro Tatiana Oliveira Passos de Araújo Patty Karina dos Santos Daiane Leite da Roza Dilson E. Rassier Anabelle Silva Cornachione 《International journal of molecular sciences》2022,23(9)
Duchenne muscular dystrophy (DMD) is a muscle disease characterized by the absence of the protein dystrophin, which causes a loss of sarcolemma integrity, determining recurrent muscle injuries, decrease in muscle function, and progressive degeneration. Currently, there is a need for therapeutic treatments to improve the quality of life of DMD patients. Here, we investigated the effects of a low-intensity aerobic training (37 sessions) on satellite cells, peroxisome proliferator-activated receptor-gamma coactivator (PGC)-1α protein (PGC-1α), and different types of fibers of the psoas muscle from mdx mice (DMD experimental model). Wildtype and mdx mice were randomly divided into sedentary and trained groups (n = 24). Trained animals were subjected to 37 sessions of low-intensity running on a motorized treadmill. Subsequently, the psoas muscle was excised and analyzed by immunofluorescence for dystrophin, satellite cells, myosin heavy chain (MHC), and PGC-1α content. The minimal Feret’s diameters of the fibers were measured, and light microscopy was applied to observe general morphological features of the muscles. The training (37 sessions) improved morphological features in muscles from mdx mice and caused an increase in the number of quiescent/activated satellite cells. It also increased the content of PGC-1α in the mdx group. We concluded that low-intensity aerobic exercise (37 sessions) was able to reverse deleterious changes determined by DMD. 相似文献
49.
Claudio Bernardazzi Morgana Teixeira Lima Castelo-Branco Beatriz Pêgo Beatriz Elias Ribeiro Siane Lopes Bittencourt Rosas Patrícia Teixeira Santana Joo Carlos Machado Camille Leal Fabiano Thompson Robson Coutinho-Silva Heitor Siffert Pereira de Souza 《International journal of molecular sciences》2022,23(9)
50.