全文获取类型
收费全文 | 15316篇 |
免费 | 945篇 |
国内免费 | 15篇 |
专业分类
电工技术 | 141篇 |
综合类 | 10篇 |
化学工业 | 3415篇 |
金属工艺 | 298篇 |
机械仪表 | 308篇 |
建筑科学 | 541篇 |
矿业工程 | 27篇 |
能源动力 | 540篇 |
轻工业 | 2691篇 |
水利工程 | 146篇 |
石油天然气 | 54篇 |
无线电 | 722篇 |
一般工业技术 | 2511篇 |
冶金工业 | 2102篇 |
原子能技术 | 95篇 |
自动化技术 | 2675篇 |
出版年
2023年 | 126篇 |
2022年 | 172篇 |
2021年 | 475篇 |
2020年 | 396篇 |
2019年 | 443篇 |
2018年 | 673篇 |
2017年 | 639篇 |
2016年 | 681篇 |
2015年 | 457篇 |
2014年 | 642篇 |
2013年 | 1085篇 |
2012年 | 986篇 |
2011年 | 1103篇 |
2010年 | 796篇 |
2009年 | 796篇 |
2008年 | 701篇 |
2007年 | 659篇 |
2006年 | 497篇 |
2005年 | 449篇 |
2004年 | 348篇 |
2003年 | 317篇 |
2002年 | 290篇 |
2001年 | 199篇 |
2000年 | 175篇 |
1999年 | 168篇 |
1998年 | 753篇 |
1997年 | 471篇 |
1996年 | 329篇 |
1995年 | 208篇 |
1994年 | 171篇 |
1993年 | 170篇 |
1992年 | 65篇 |
1991年 | 71篇 |
1990年 | 57篇 |
1989年 | 56篇 |
1988年 | 48篇 |
1987年 | 46篇 |
1986年 | 46篇 |
1985年 | 47篇 |
1984年 | 38篇 |
1983年 | 36篇 |
1982年 | 41篇 |
1981年 | 51篇 |
1980年 | 41篇 |
1979年 | 14篇 |
1978年 | 19篇 |
1977年 | 44篇 |
1976年 | 74篇 |
1975年 | 14篇 |
1973年 | 21篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Brito Claúdia Esteves Marisa Peixoto Hugo Abelha António Machado José 《Wireless Networks》2022,28(3):1269-1277
Wireless Networks - Continuous ambulatory peritoneal dialysis (CAPD) is a treatment used by patients in the end-stage of chronic kidney diseases. Those patients need to be monitored using blood... 相似文献
2.
Chanh Constance Gourment Anaïs Petit Betrand Gourgues-Lorenzon Anne-Françoise 《International Journal of Fracture》2022,235(2):215-230
International Journal of Fracture - The development of high-performance automotive steels involves increasingly complex chemistries and heat treating sequences, to produce stronger and lighter... 相似文献
3.
4.
Policicchio Alfonso Putz Ana-Maria Conte Giuseppe Stelitano Sara Bonaventura Carlo Poselle Ianăşi Cătălin Almásy László Wacha András Horváth Zsolt Endre Agostino Raffaele G. 《Journal of Porous Materials》2021,28(4):1049-1058
Journal of Porous Materials - The present study reports a systematic analysis of morphology and hydrogen sorption capacity of mesoporous organic-inorganic silica prepared by varying the silica... 相似文献
5.
Sofia Cotton Dylan Ferreira Janine Soares Andreia Peixoto Marta Relvas-Santos Rita Azevedo Paulina Piairo Lorena Diguez Carlos Palmeira Luís Lima Andr M. N. Silva Lúcio Lara Santos Jos Alexandre Ferreira 《International journal of molecular sciences》2021,22(4)
Esophageal cancer (EC) is a life-threatening disease, demanding the discovery of new biomarkers and molecular targets for precision oncology. Aberrantly glycosylated proteins hold tremendous potential towards this objective. In the current study, a series of esophageal squamous cell carcinomas (ESCC) and EC-derived circulating tumor cells (CTCs) were screened by immunoassays for the sialyl-Tn (STn) antigen, a glycan rarely expressed in healthy tissues and widely observed in aggressive gastrointestinal cancers. An ESCC cell model was glycoengineered to express STn and characterized in relation to cell proliferation and invasion in vitro. STn was found to be widely present in ESCC (70% of tumors) and in CTCs in 20% of patients, being associated with general recurrence and reduced survival. Furthermore, STn expression in ESCC cells increased invasion in vitro, while reducing cancer cells proliferation. In parallel, an ESCC mass spectrometry-based proteomics dataset, obtained from the PRIDE database, was comprehensively interrogated for abnormally glycosylated proteins. Data integration with the Target Score, an algorithm developed in-house, pinpointed the glucose transporter type 1 (GLUT1) as a biomarker of poor prognosis. GLUT1-STn glycoproteoforms were latter identified in tumor tissues in patients facing worst prognosis. Furthermore, healthy human tissues analysis suggested that STn glycosylation provided cancer specificity to GLUT1. In conclusion, STn is a biomarker of worst prognosis in EC and GLUT1-STn glycoforms may be used to increase its specificity on the stratification and targeting of aggressive ESCC forms. 相似文献
6.
7.
Improved Controlled Release and Brain Penetration of the Small Molecule S14 Using PLGA Nanoparticles
Vanesa Nozal Elisa Rojas-Prats Ins Maestro Carmen Gil Daniel I. Perez Ana Martinez 《International journal of molecular sciences》2021,22(6)
Phosphodiesterase 7 (PDE7) is an enzyme responsible for the degradation of cyclic adenosine monophosphate (cAMP), an important cellular messenger. PDE7’s role in neurotransmission, expression profile in the brain and the druggability of other phosphodiesterases have motivated the search for potent inhibitors to treat neurodegenerative and inflammatory diseases. Different heterocyclic compounds have been described over the years; among them, phenyl-2-thioxo-(1H)-quinazolin-4-one, called S14, has shown very promising results in different in vitro and in vivo studies. Recently, polymeric nanoparticles have been used as new formulations to target specific organs and produce controlled release of certain drugs. In this work, we describe poly(lactic-co-glycolic acid) (PLGA)-based polymeric nanoparticles loaded with S14. Their preparation, optimization, characterization and in vivo drug release profile are here presented as an effort to improve pharmacokinetic properties of this interesting PDE7 inhibitor. 相似文献
8.
Julia Peas-Martínez María N. Barrachina Ernesto Jos Cuenca-Zamora Gins Luengo-Gil Susana Beln Bravo Eva Caparrs-Prez Raúl Teruel-Montoya Jos Eliseo-Blanco Vicente Vicente ngel García Irene Martínez-Martínez Francisca Ferrer-Marín 《International journal of molecular sciences》2021,22(4)
Exosomes are extracellular vesicles that contain nucleic acids, lipids and metabolites, and play a critical role in health and disease as mediators of intercellular communication. The majority of extracellular vesicles in the blood are platelet-derived. Compared to adults, neonatal platelets are hyporeactive and show impaired granule release, associated with defects in Soluble N-ethylmaleimide-sensitive fusion Attachment protein REceptor (SNARE) proteins. Since these proteins participate in biogenesis of exosomes, we investigated the potential differences between newborn and adult plasma-derived exosomes. Plasma-derived exosomes were isolated by ultracentrifugation of umbilical cord blood from full-term neonates or peripheral blood from adults. Exosome characterization included size determination by transmission electron microscopy and quantitative proteomic analysis. Plasma-derived exosomes from neonates were significantly smaller and contained 65% less protein than those from adults. Remarkably, 131 proteins were found to be differentially expressed, 83 overexpressed and 48 underexpressed in neonatal (vs. adult) exosomes. Whereas the upregulated proteins in plasma exosomes from neonates are associated with platelet activation, coagulation and granule secretion, most of the underexpressed proteins are immunoglobulins. This is the first study showing that exosome size and content change with age. Our findings may contribute to elucidating the potential “developmental hemostatic mismatch risk” associated with transfusions containing plasma exosomes from adults. 相似文献
9.
Angelika Varga Zoltn Mszr Mikls Sivad Tímea Bcskai Bence Vgh va Kkai Istvn Nagy Pter Szücs 《International journal of molecular sciences》2021,22(5)
The phosphorylation of serine 10 in histone 3 (p-S10H3) has recently been demonstrated to participate in spinal nociceptive processing. However, superficial dorsal horn (SDH) neurons involved in p-S10H3-mediated nociception have not been fully characterized. In the present work, we combined immunohistochemistry, in situ hybridization with the retrograde labeling of projection neurons to reveal the subset of dorsal horn neurons presenting an elevated level of p-S10H3 in response to noxious heat (60 °C), causing burn injury. Projection neurons only represented a small percentage (5%) of p-S10H3-positive cells, while the greater part of them belonged to excitatory SDH interneurons. The combined immunolabeling of p-S10H3 with markers of already established interneuronal classes of the SDH revealed that the largest subset of neurons with burn injury-induced p-S10H3 expression was dynorphin immunopositive in mice. Furthermore, the majority of p-S10H3-expressing dynorphinergic neurons proved to be excitatory, as they lacked Pax-2 and showed Lmx1b-immunopositivity. Thus, we showed that neurochemically heterogeneous SDH neurons exhibit the upregulation of p-S10H3 shortly after noxious heat-induced burn injury and consequential tissue damage, and that a dedicated subset of excitatory dynorphinergic neurons is likely a key player in the development of central sensitization via the p-S10H3 mediated pathway. 相似文献
10.
Aguayo-Canela Francisco José Alaiz-Moretón Héctor García-Ordás María Teresa Benítez-Andrades José Alberto Benavides Carmen García-Rodríguez Isaías 《The Journal of supercomputing》2021,77(11):13046-13068
The Journal of Supercomputing - The increasing number of connected devices and the complexity of Internet of Things (IoT) ecosystems are demanding new architectures for managing and securing these... 相似文献