全文获取类型
收费全文 | 2823篇 |
免费 | 188篇 |
国内免费 | 5篇 |
专业分类
电工技术 | 13篇 |
综合类 | 2篇 |
化学工业 | 907篇 |
金属工艺 | 18篇 |
机械仪表 | 56篇 |
建筑科学 | 130篇 |
能源动力 | 56篇 |
轻工业 | 580篇 |
水利工程 | 36篇 |
石油天然气 | 9篇 |
无线电 | 135篇 |
一般工业技术 | 434篇 |
冶金工业 | 299篇 |
原子能技术 | 8篇 |
自动化技术 | 333篇 |
出版年
2024年 | 11篇 |
2023年 | 69篇 |
2022年 | 211篇 |
2021年 | 255篇 |
2020年 | 106篇 |
2019年 | 117篇 |
2018年 | 138篇 |
2017年 | 111篇 |
2016年 | 107篇 |
2015年 | 116篇 |
2014年 | 111篇 |
2013年 | 195篇 |
2012年 | 172篇 |
2011年 | 217篇 |
2010年 | 124篇 |
2009年 | 143篇 |
2008年 | 121篇 |
2007年 | 123篇 |
2006年 | 87篇 |
2005年 | 73篇 |
2004年 | 55篇 |
2003年 | 51篇 |
2002年 | 38篇 |
2001年 | 12篇 |
2000年 | 19篇 |
1999年 | 24篇 |
1998年 | 18篇 |
1997年 | 22篇 |
1996年 | 14篇 |
1995年 | 11篇 |
1994年 | 9篇 |
1993年 | 9篇 |
1992年 | 11篇 |
1990年 | 8篇 |
1989年 | 8篇 |
1988年 | 10篇 |
1987年 | 6篇 |
1986年 | 7篇 |
1985年 | 9篇 |
1984年 | 5篇 |
1983年 | 8篇 |
1982年 | 7篇 |
1981年 | 4篇 |
1977年 | 6篇 |
1976年 | 4篇 |
1975年 | 3篇 |
1973年 | 4篇 |
1972年 | 3篇 |
1964年 | 3篇 |
1958年 | 2篇 |
排序方式: 共有3016条查询结果,搜索用时 0 毫秒
141.
Sara M. dos S. Pizzatto Fernando Otavio Pizzatto Elidio Angioletto Sabrina Arcaro Eduardo Junca Oscar R. Klegues Montedo 《International Journal of Applied Ceramic Technology》2021,18(5):1734-1742
The effects of porous ceramic plates on the thermal behavior of ventilated façades were evaluated, and the results are presented herein. Thermal behavior in a ventilated façade of specimens containing 40 wt% of lime mud and a firing temperature of 1100°C was evaluated and compared with a commercial porcelain ceramic tile, which was the reference material. An experimental apparatus was designed to evaluate the thermal performance of the studied ventilated façades. The results revealed that the ventilated façade composed of the studied porous ceramic tiles produced a greater reduction in temperature between the external environmental and the interior of a box representing a building (ΔT5) of 65.7°C, compared with the façade composed of the commercial porcelain ceramic tiles (ΔT5 = 56.0°C) and even the traditional façade (ΔT5 = 49.1°C). Thus, porous ceramic tiles based on byproducts are promising candidates for ventilated façade systems. 相似文献
142.
Sara Izadyar Mohammad Reza Hantehzadeh Mahmood Ghoranneviss Seyed Mohammad Elahi Arash Boochani 《Protection of Metals and Physical Chemistry of Surfaces》2016,52(6):1043-1045
Cu–Ni nanoparticles (NPs) thin films were prepared by Direct Current (DC) magnetron sputtering with Cu and Ni targets. The products were used as catalysts for Thermal CVD (TCVD) growing of carbon nanotubes (CNTs) from acetylene gas at 825°C. In order to characterize the nano catalysts, X-ray Diffraction (XRD) and Atomic Force Microscopy (AFM) and to study the synthesized CNTs Scanning Electron Microscopy (SEM) and Raman Spectroscopy were applied. A remarkable CNT grown on the sub-surface of catalyst layer compared to its top is deduced from SEM images. Despite the poor catalytic activity of the top-surface, these considerations led us to conclude more catalytic activity of the sub-surface. 相似文献
143.
Sara Morais Mnica Pereira Catarina Lau Ana Gonalves Catarina Monteiro Marta Gonalves Jorge Oliveira Lurdes Moreira Eugnia Cruz Rosrio Santos Margarida Lima 《International journal of molecular sciences》2021,22(22)
RASGRP2 encodes the calcium and diacylglycerol (DAG)-regulated guanine nucleotide exchange factor I (CalDAG-GEFI) identified as a Rap1-activating molecule. Pathogenic variants previously identified in RASGRP2 allowed the characterization of CalDAG-GEFI deficiency as a non-syndromic, autosomal recessive platelet function disease. We report on the clinical manifestations and laboratory features of a Portuguese family with a likely pathogenic variant in RASGRP2 (c.999G>C leading to a p.Lys333Asn change in the CDC25 catalytic domain of CalDAG-GEFI) and discuss the contribution of this variant to the disease manifestations. Based on the study of this family with one homozygous patient and five heterozygous carriers and on a critical analysis of the literature, we challenge previous knowledge that CalDAG-GEFI deficiency only manifests in homozygous patients. Our data suggest that at least for the RASGRP2 variant reported herein, there is a phenotypic expression, albeit milder, in heterozygous carriers. 相似文献
144.
Eleonora Persoons Sara Kerselaers Thomas Voets Joris Vriens Katharina Held 《International journal of molecular sciences》2021,22(24)
Sex hormone steroidal drugs were reported to have modulating actions on the ion channel TRPM3. Pregnenolone sulphate (PS) presents the most potent known endogenous chemical agonist of TRPM3 and affects several gating modes of the channel. These includes a synergistic action of PS and high temperatures on channel opening and the PS-induced opening of a noncanonical pore in the presence of other TRPM3 modulators. Moreover, human TRPM3 variants associated with neurodevelopmental disease exhibit an increased sensitivity for PS. However, other steroidal sex hormones were reported to influence TRPM3 functions with activating or inhibiting capacity. Here, we aimed to answer how DHEAS, estradiol, progesterone and testosterone act on the various modes of TRPM3 function in the wild-type channel and two-channel variants associated with human disease. By means of calcium imaging and whole-cell patch clamp experiments, we revealed that all four drugs are weak TRPM3 agonists that share a common steroidal interaction site. Furthermore, they exhibit increased activity on TRPM3 at physiological temperatures and in channels that carry disease-associated mutations. Finally, all steroids are able to open the noncanonical pore in wild-type and DHEAS also in mutant TRPM3. Collectively, our data provide new valuable insights in TRPM3 gating, structure-function relationships and ligand sensitivity. 相似文献
145.
146.
Elia Bari Ilaria Roato Giuseppe Perale Filippo Rossi Tullio Genova Federico Mussano Riccardo Ferracini Marzio Sorlini Maria Luisa Torre Sara Perteghella 《International journal of molecular sciences》2021,22(8)
SmartBone® (SB) is a biohybrid bone substitute advantageously proposed as a class III medical device for bone regeneration in reconstructive surgeries (oral, maxillofacial, orthopedic, and oncology). In the present study, a new strategy to improve SB osteoinductivity was developed. SB scaffolds were loaded with lyosecretome, a freeze-dried formulation of mesenchymal stem cell (MSC)-secretome, containing proteins and extracellular vesicles (EVs). Lyosecretome-loaded SB scaffolds (SBlyo) were prepared using an absorption method. A burst release of proteins and EVs (38% and 50% after 30 min, respectively) was observed, and then proteins were released more slowly with respect to EVs, most likely because they more strongly adsorbed onto the SB surface. In vitro tests were conducted using adipose tissue-derived stromal vascular fraction (SVF) plated on SB or SBlyo. After 14 days, significant cell proliferation improvement was observed on SBlyo with respect to SB, where cells filled the cavities between the native trabeculae. On SB, on the other hand, the process was still present, but tissue formation was less organized at 60 days. On both scaffolds, cells differentiated into osteoblasts and were able to mineralize after 60 days. Nonetheless, SBlyo showed a higher expression of osteoblast markers and a higher quantity of newly formed trabeculae than SB alone. The quantification analysis of the newly formed mineralized tissue and the immunohistochemical studies demonstrated that SBlyo induces bone formation more effectively. This osteoinductive effect is likely due to the osteogenic factors present in the lyosecretome, such as fibronectin, alpha-2-macroglobulin, apolipoprotein A, and TGF-β. 相似文献
147.
148.
149.
Marta Gowacka Sara Lipka Ewelina Mynarska Beata Franczyk Jacek Rysz 《International journal of molecular sciences》2021,22(15)
COVID-19 is mainly considered a respiratory illness, but since SARS-CoV-2 uses the angiotensin converting enzyme 2 receptor (ACE2) to enter human cells, the kidney is also a target of the viral infection. Acute kidney injury (AKI) is the most alarming condition in COVID-19 patients. Recent studies have confirmed the direct entry of SARS-CoV-2 into the renal cells, namely podocytes and proximal tubular cells, but this is not the only pathomechanism of kidney damage. Hypovolemia, cytokine storm and collapsing glomerulopathy also play an important role. An increasing number of papers suggest a strong association between AKI development and higher mortality in COVID-19 patients, hence our interest in the matter. Although knowledge about the role of kidneys in SARS-CoV-2 infection is changing dynamically and is yet to be fully investigated, we present an insight into the possible pathomechanisms of AKI in COVID-19, its clinical features, risk factors, impact on hospitalization and possible ways for its management via renal replacement therapy. 相似文献
150.
Sara Bravaccini Giuseppe Bronte Paola Ulivi 《International journal of molecular sciences》2021,22(12)
Although immune checkpoint inhibitors have changed the treatment paradigm of a variety of cancers, including non-small-cell lung cancer, not all patients respond to immunotherapy in the same way. Predictive biomarkers for patient selection are thus needed. Tumor mutation burden (TMB), defined as the total number of somatic/acquired mutations per coding area of a tumor genome (Mut/Mb), has emerged as a potential predictive biomarker of response to immune checkpoint inhibitors. We found that the limited use of TMB in clinical practice is due to the difficulty in its detection and compounded by several different biological, methodological and economic issues. The incorporation of both TMB and PD-L1 expression or other biomarkers into multivariable predictive models could result in greater predictive power. 相似文献