全文获取类型
收费全文 | 545篇 |
免费 | 29篇 |
专业分类
电工技术 | 6篇 |
综合类 | 3篇 |
化学工业 | 207篇 |
金属工艺 | 12篇 |
机械仪表 | 7篇 |
建筑科学 | 26篇 |
矿业工程 | 3篇 |
能源动力 | 6篇 |
轻工业 | 83篇 |
水利工程 | 3篇 |
无线电 | 17篇 |
一般工业技术 | 77篇 |
冶金工业 | 29篇 |
原子能技术 | 2篇 |
自动化技术 | 93篇 |
出版年
2024年 | 2篇 |
2023年 | 9篇 |
2022年 | 24篇 |
2021年 | 29篇 |
2020年 | 11篇 |
2019年 | 16篇 |
2018年 | 8篇 |
2017年 | 11篇 |
2016年 | 22篇 |
2015年 | 17篇 |
2014年 | 17篇 |
2013年 | 34篇 |
2012年 | 31篇 |
2011年 | 36篇 |
2010年 | 29篇 |
2009年 | 44篇 |
2008年 | 38篇 |
2007年 | 28篇 |
2006年 | 34篇 |
2005年 | 17篇 |
2004年 | 22篇 |
2003年 | 23篇 |
2002年 | 14篇 |
2001年 | 9篇 |
2000年 | 6篇 |
1999年 | 9篇 |
1998年 | 3篇 |
1996年 | 2篇 |
1995年 | 4篇 |
1994年 | 6篇 |
1993年 | 2篇 |
1992年 | 4篇 |
1991年 | 2篇 |
1989年 | 3篇 |
1988年 | 3篇 |
1984年 | 1篇 |
1981年 | 2篇 |
1978年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有574条查询结果,搜索用时 15 毫秒
21.
Abstract Linear codes are developed and their low-density-burst-error correction capabilities are described in terms of various digits of a code word. 相似文献
22.
23.
Claudia Pielsticker Martin F. Brodde Lisa Raum Kerstin Jurk Beate E. Kehrel 《International journal of molecular sciences》2020,21(22)
Inflammatory processes are triggered by the fibrinolytic enzyme plasmin. Tissue-type plasminogen activator, which cleaves plasminogen to plasmin, can be activated by the cross-β-structure of misfolded proteins. Misfolded protein aggregates also represent substrates for plasmin, promoting their degradation, and are potent platelet agonists. However, the regulation of plasmin-mediated platelet activation by misfolded proteins and vice versa is incompletely understood. In this study, we hypothesize that plasmin acts as potent agonist of human platelets in vitro after short-term incubation at room temperature, and that the response to thrombospondin-1 and the bona fide misfolded proteins Eap and SCN−-denatured IgG interfere with plasmin, thereby modulating platelet activation. Plasmin dose-dependently induced CD62P surface expression on, and binding of fibrinogen to, human platelets in the absence/presence of plasma and in citrated whole blood, as analyzed by flow cytometry. Thrombospondin-1 pre-incubated with plasmin enhanced these plasmin-induced platelet responses at low concentration and diminished them at higher dose. Platelet fibrinogen binding was dose-dependently induced by the C-terminal thrombospondin-1 peptide RFYVVMWK, Eap or NaSCN-treated IgG, but diminished in the presence of plasmin. Blocking enzymatically catalyzed thiol-isomerization decreased plasmin-induced platelet responses, suggesting that plasmin activates platelets in a thiol-dependent manner. Thrombospondin-1, depending on the concentration, may act as cofactor or inhibitor of plasmin-induced platelet activation, and plasmin blocks platelet activation induced by misfolded proteins and vice versa, which might be of clinical relevance. 相似文献
24.
Dr. Aline Telzerow Dr. Juraj Paris Dr. Maria Håkansson Dr. Javier González-Sabín Dr. Nicolas Ríos-Lombardía Prof. Dr. Harald Gröger Dr. Francisco Morís Dr. Martin Schürmann Prof. Dr. Helmut Schwab Dr. Kerstin Steiner 《Chembiochem : a European journal of chemical biology》2021,22(7):1232-1242
Amine transaminases (ATAs) are used to synthesize enantiomerically pure amines, which are building blocks for pharmaceuticals and agrochemicals. R-selective ATAs belong to the fold type IV PLP-dependent enzymes, and different sequence-, structure- and substrate scope-based features have been identified in the past decade. However, our knowledge is still restricted due to the limited number of characterized (R)-ATAs, with additional bias towards fungal origin. We aimed to expand the toolbox of (R)-ATAs and contribute to the understanding of this enzyme subfamily. We identified and characterized four new (R)-ATAs. The ATA from Exophiala sideris contains a motif characteristic for d -ATAs, which was previously believed to be a disqualifying factor for (R)-ATA activity. The crystal structure of the ATA from Shinella is the first from a Gram-negative bacterium. The ATAs from Pseudonocardia acaciae and Tetrasphaera japonica are the first characterized (R)-ATAs with a shortened/missing N-terminal helix. The active-site charges vary significantly between the new and known ATAs, correlating with their diverging substrate scope. 相似文献
25.
Yüksel Korkmaz Behrus Puladi Kerstin Galler Peer W. Kmmerer Agnes Schrder Lina Glz Tim Sparwasser Wilhelm Bloch Andreas Friebe James Deschner 《International journal of molecular sciences》2021,22(2)
Nitric oxide (NO) binds to soluble guanylyl cyclase (sGC), activates it in a reduced oxidized heme iron state, and generates cyclic Guanosine Monophosphate (cGMP), which results in vasodilatation and inhibition of osteoclast activity. In inflammation, sGC is oxidized and becomes insensitive to NO. NO- and heme-independent activation of sGC requires protein expression of the α1- and β1-subunits. Inflammation of the periodontium induces the resorption of cementum by cementoclasts and the resorption of the alveolar bone by osteoclasts, which can lead to tooth loss. As the presence of sGC in cementoclasts is unknown, we investigated the α1- and β1-subunits of sGC in cementoclasts of healthy and inflamed human periodontium using double immunostaining for CD68 and cathepsin K and compared the findings with those of osteoclasts from the same sections. In comparison to cementoclasts in the healthy periodontium, cementoclasts under inflammatory conditions showed a decreased staining intensity for both α1- and β1-subunits of sGC, indicating reduced protein expression of these subunits. Therefore, pharmacological activation of sGC in inflamed periodontal tissues in an NO- and heme-independent manner could be considered as a new treatment strategy to inhibit cementum resorption. 相似文献
26.
Kerstin Potthoff 《Landscape Research》2017,42(1):63-77
The study investigates spatio-temporal patterns of birch regrowth in a mountain valley in which intensive livestock grazing was formerly practised. Vegetation changes were identified through analysis of three sets of aerial photographs. The results of GIS analyses, one-way ANOVA and PCA showed that regrowth patterns are complex. In the early phase of succession, grazing history has a strong impact on where new forest establishes, both at a distance from the seasonal farmsteads where grazing intensity prior to abandonment was highest, and close to previously existing forest. Sprouting is most likely to be the dominating regeneration strategy in this early phase. In a later phase of succession, the impact of grazing history on forest distribution patterns decreases, as exemplified by the increasing distance from existing forest. The largest amounts of birch forest then establish in warm locations with moderate moisture. Protection against wind appears to be important for birch establishment. 相似文献
27.
Chemikalienfreie Bekämpfung von Holzschädlingen durch dielektrische Erwärmung mit Radiowellen und Mikrowellen
下载免费PDF全文
![点击此处可从《化学,工程师,技术》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Christian Hoyer Christian Pfütze Dr. Rudy Plarre Dr. Ulf Trommler Steffen Steinbach Kerstin Klutzny Dr. Frank Holzer Carsten Rabe Björn Höhlig Prof. Frank‐Dieter Kopinke Prof. Detlef Schmidt Dr. Ulf Roland 《化学,工程师,技术》2014,86(8):1187-1197
Thermal pest control requires long treatment times due to the low thermal conductivity of wood and may lead to the formation of cracks. Here, the thermal treatment with radio waves as well as microwaves has been studied. The direct dielectric heating has the advantage of a good homogeneity. The obtained temperature profiles for radio waves were more homogeneous compared to microwaves. Detailed studies showed that elimination of pests was not related to the application of the electromagnetic field itself, but due to the temperature increase. 相似文献
28.
29.
Sandrine Baltzer Timur Bulatov Christopher Schmied Andreas Krmer Benedict-Tilman Berger Andreas Oder Ryan Walker-Gray Christin Kuschke Kerstin Zühlke Jenny Eichhorst Martin Lehmann Stefan Knapp John Weston Jens Peter von Kries Roderich D. Süssmuth Enno Klussmann 《International journal of molecular sciences》2022,23(2)
The cAMP-dependent aquaporin-2 (AQP2) redistribution from intracellular vesicles into the plasma membrane of renal collecting duct principal cells induces water reabsorption and fine-tunes body water homeostasis. However, the mechanisms controlling the localization of AQP2 are not understood in detail. Using immortalized mouse medullary collecting duct (MCD4) and primary rat inner medullary collecting duct (IMCD) cells as model systems, we here discovered a key regulatory role of Aurora kinase A (AURKA) in the control of AQP2. The AURKA-selective inhibitor Aurora-A inhibitor I and novel derivatives as well as a structurally different inhibitor, Alisertib, prevented the cAMP-induced redistribution of AQP2. Aurora-A inhibitor I led to a depolymerization of actin stress fibers, which serve as tracks for the translocation of AQP2-bearing vesicles to the plasma membrane. The phosphorylation of cofilin-1 (CFL1) inactivates the actin-depolymerizing function of CFL1. Aurora-A inhibitor I decreased the CFL1 phosphorylation, accounting for the removal of the actin stress fibers and the inhibition of the redistribution of AQP2. Surprisingly, Alisertib caused an increase in actin stress fibers and did not affect CFL1 phosphorylation, indicating that AURKA exerts its control over AQP2 through different mechanisms. An involvement of AURKA and CFL1 in the control of the localization of AQP2 was hitherto unknown. 相似文献
30.
The objective of this study was to investigate how color stability of beef is affected by vacuum skin packaging (VSP) compared with vacuum packaging (VP) and high-oxygen modified atmosphere packaging (MAP; 80% O(2) and 20% CO(2)). Longissimus lumborum muscles were aged in vacuum for 7days and then cut into 2-cm-thick slices and repacked using VSP, VP and MAP for another 7days. Color stability was measured during the next 5days in air and samples for α-tocopherol and NADH analyses were obtained at the beginning and end of aerobic storage. Color stability, α-tocopherol and NADH of steaks were affected by packaging methods and storage time in air (P<0.05). Higher a* value was obtained in VSP on day 5 compared with VP. Steaks packed in VSP had better color stability than in VP and their color was similar to MAP at the end (day 5) of storage. 相似文献