全文获取类型
| 收费全文 | 275篇 |
| 免费 | 2篇 |
专业分类
| 电工技术 | 2篇 |
| 化学工业 | 89篇 |
| 机械仪表 | 6篇 |
| 建筑科学 | 8篇 |
| 矿业工程 | 1篇 |
| 能源动力 | 13篇 |
| 轻工业 | 47篇 |
| 水利工程 | 4篇 |
| 石油天然气 | 4篇 |
| 无线电 | 9篇 |
| 一般工业技术 | 45篇 |
| 冶金工业 | 8篇 |
| 原子能技术 | 1篇 |
| 自动化技术 | 40篇 |
出版年
| 2024年 | 4篇 |
| 2023年 | 3篇 |
| 2022年 | 28篇 |
| 2021年 | 21篇 |
| 2020年 | 9篇 |
| 2019年 | 13篇 |
| 2018年 | 7篇 |
| 2017年 | 7篇 |
| 2016年 | 8篇 |
| 2015年 | 6篇 |
| 2014年 | 15篇 |
| 2013年 | 12篇 |
| 2012年 | 18篇 |
| 2011年 | 28篇 |
| 2010年 | 22篇 |
| 2009年 | 13篇 |
| 2008年 | 13篇 |
| 2007年 | 6篇 |
| 2006年 | 10篇 |
| 2005年 | 9篇 |
| 2004年 | 2篇 |
| 2003年 | 3篇 |
| 2002年 | 4篇 |
| 2001年 | 4篇 |
| 2000年 | 1篇 |
| 1999年 | 2篇 |
| 1998年 | 2篇 |
| 1996年 | 1篇 |
| 1995年 | 1篇 |
| 1993年 | 1篇 |
| 1992年 | 2篇 |
| 1990年 | 1篇 |
| 1989年 | 1篇 |
排序方式： 共有277条查询结果，搜索用时 15 毫秒
91.
Paula Alonso-Ramos David lvarez-Melo Katerina Strouhalova Carolina Pascual-Silva George B. Garside Meret Arter Teresa Bermejo Rokas Grigaitis Rahel Wettstein Marta Fernndez-Díaz Joao Matos Marco Geymonat Pedro A. San-Segundo Jesús A. Carballo 《International journal of molecular sciences》2021,22(18)
Meiotic defects derived from incorrect DNA repair during gametogenesis can lead to mutations, aneuploidies and infertility. The coordinated resolution of meiotic recombination intermediates is required for crossover formation, ultimately necessary for the accurate completion of both rounds of chromosome segregation. Numerous master kinases orchestrate the correct assembly and activity of the repair machinery. Although much less is known, the reversal of phosphorylation events in meiosis must also be key to coordinate the timing and functionality of repair enzymes. Cdc14 is a crucial phosphatase required for the dephosphorylation of multiple CDK1 targets in many eukaryotes. Mutations that inactivate this phosphatase lead to meiotic failure, but until now it was unknown if Cdc14 plays a direct role in meiotic recombination. Here, we show that the elimination of Cdc14 leads to severe defects in the processing and resolution of recombination intermediates, causing a drastic depletion in crossovers when other repair pathways are compromised. We also show that Cdc14 is required for the correct activity and localization of the Holliday Junction resolvase Yen1/GEN1. We reveal that Cdc14 regulates Yen1 activity from meiosis I onwards, and this function is essential for crossover resolution in the absence of other repair pathways. We also demonstrate that Cdc14 and Yen1 are required to safeguard sister chromatid segregation during the second meiotic division, a late action that is independent of the earlier role in crossover formation. Thus, this work uncovers previously undescribed functions of the evolutionary conserved Cdc14 phosphatase in the regulation of meiotic recombination. 相似文献
92.
Veronika Palenikova Michaela Frolikova Eliska Valaskova Pavla Postlerova Katerina Komrskova 《International journal of molecular sciences》2021,22(17)
Integrins are transmembrane receptors that facilitate cell adhesion and cell–extracellular matrix communication. They are involved in the sperm maturation including capacitation and gamete interaction, resulting in successful fertilization. αV integrin belongs to the integrin glycoprotein superfamily, and it is indispensable for physiological spermiogenesis and testosterone production. We targeted the gene and protein expression of the αV integrin subunit and described its membrane localization in sperm. Firstly, in mouse, we traced αV integrin gene expression during spermatogenesis in testicular fraction separated by elutriation, and we detected gene activity in spermatogonia, spermatocytes, and round spermatids. Secondly, we specified αV integrin membrane localization in acrosome-intact and acrosome-reacted sperm and compared its pattern between mouse, pig, and human. Using immunodetection and structured illumination microscopy (SIM), the αV integrin localization was confined to the plasma membrane covering the acrosomal cap area and also to the inner acrosomal membrane of acrosome-intact sperm of all selected species. During the acrosome reaction, which was induced on capacitated sperm, the αV integrin relocated and was detected over the whole sperm head. Knowledge of the integrin pattern in mature sperm prepares the ground for further investigation into the pathologies and related fertility issues in human medicine and veterinary science. 相似文献
93.
94.
Maja Jordanova Katerina Rebok Fernanda Malhão Maria J. Rocha Eduardo Rocha 《Microscopy research and technique》2016,79(8):700-706
This study on wild female Ohrid trout was primarily designed to provide a general overview of the breeding cycle influence upon selected aspects of hepatocytes. According with a semiquantitatively evaluation, some of these cell's structural compartments change during the breeding cycle. Structural modifications were disclosed in the relative occurrence of lipid, glycogen, and RER content during breeding cycle. The relative amount of lipid deposits in the hepatocytes was much greater in previtellogenesis, and decreased postspawning. So, while the seasonal changes in RER were positively related with the ovary maturation status, those of the lipid droplets followed an opposite trend. The hepatocytic glycogen occurred rarely, mainly in late‐vitellogenesis and spawning, suggesting that in this species such kind of energy storage is comparatively unimportant. Lipid accumulation and later usage is, probably, the relevant biochemical pathway for Ohrid trout in the wild. While glycogen and RER contents were positively correlated with the gonadosomatic index, lipids were negatively correlated. Additionally, glycogen inclusions were positively correlated with the plasma estradiol levels. When comparing seasonal patterns from wild Ohrid trout with those from well‐studied rainbow and brown trout (specimens studied were from aquaculture), there are contradicting results as to lipid and glycogen reserves, and also as to RER loads. The differences among the mentioned trout can result from intrinsic interspecies differences or may be associated with natural feeding conditions versus feeding with commercially prepared diets, or other factors. This study offers new data useful as standard to access liver pathology in wild and aquacultured Ohrid trout. Microsc. Res. Tech. 79:700–706, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
95.
Bart van Dam Hui Nie Bo Ju Emanuele Marino Jos M. J. Paulusse Peter Schall Minjie Li Katerina Dohnalová 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(48)
Carbon dots (CDs) are carbon‐based fluorescent nanoparticles that can exhibit excitation‐dependent photoluminescence (PL) “tunable” throughout the entire visible range, interesting for optoelectronic and imaging applications. The mechanism underlying this tunable emission remains largely debated, most prominently being ascribed to dot‐to‐dot variations that ultimately lead to excitation‐dependent ensemble properties. Here, single‐dot spectroscopy is used to elucidate the origin of the excitation‐dependent PL of CDs. It is demonstrated that already single CDs exhibit excitation‐dependent PL spectra, similar to those of the CD ensemble. The single dots, produced by a facile one‐step synthesis from chloroform and diethylamine, exhibit emission spectra with several characteristic peaks differing in emission peak position and spectral width and shape, indicating the presence of distinct emission sites on the CDs. Based on previous work, these emission sites are related to the sp2 subregions in the carbon core, as well as the functional groups on the surface. These results confirm that it is possible to integrate and engineer different types of electronic transitions at the nanoscale on a single CD, making these CDs even more versatile than organic dyes or inorganic quantum dots and opening up new routes toward light‐emission engineering. 相似文献
96.
Katerina Girginova 《Digital Creativity》2017,28(1):8-23
ABSTRACTThis paper analyzes #savethesurprise, the hugely successful social media campaign launched prior to the London 2012 Olympic Games. In brief, #savethesurprise helped to persuade over 100,000 audience members not to divulge on social media any of what they saw during the two, live dress rehearsals of the Games’ opening ceremony; this ceremony then went on to become a part of the most watched television event in history. To explore how and why the campaign worked, this paper introduces the concept of ‘architectures of participation’ (AoP). AoP are socio-technical structures and practices that shape the ways in which people and organizations co-construct events and realities via communication. By applying this concept to the #savethesurprise campaign, this paper presents a participatory architecture undergirded by strong legal, technical and social layers. Furthermore, a sense of creative citizenship and fair play emerge as key audience motivators. 相似文献
97.
Anne-Marie Reißner Susanne Struck Katerina Alba Cristina Proserpio Roberto Foschino Charlotta Turner Isabel Hernando Susann Zahn Harald Rohm 《International Journal of Food Science & Technology》2021,56(10):5007-5016
Juice-pressing residues, among them blackcurrant pomace, are valuable materials for being upgraded in food products. Their excellent nutritional profiles in line with their functional properties allow a wide range of applications. The current study was performed to evaluate the overall liking of a pomace-enriched thin crispy-baked bread product in five European countries, and to obtain suggestions for improvements. Moreover, data on the frequency of snack consumption, openness to new foods and an opinion on residues in food applications were acquired. Four hundred and sixty-six consumers from United Kingdom, Spain, Sweden, Italy and Germany were involved. On a 9-point hedonic scale, the pomace cracker was rated towards the direction of liking with 5.94 ± 1.90 on average. Contingency tables showed that the overall-liking correlated highly significant (p < 0.01) with the country of origin and sex of the respondents and their openness to new products. Significantly higher liking scores were provided by British and Spanish consumers and, among these respondents, savoury snacks were stated to be consumed most frequently. Therefore, the snack consumption frequency also appeared to be a driver for cross-national differences in hedonic responses. The consent for using pomace in food products was remarkably high (>90%) in all countries and stresses consumer awareness in terms of healthy longevity and sustainability. 相似文献
98.
Vera Kmonickova Michaela Frolikova Klaus Steger Katerina Komrskova 《International journal of molecular sciences》2020,21(23)
The LINC (LInker of Nucleoskeleton and Cytoskeleton) complex is localized within the nuclear envelope and consists of SUN (Sad1/UNc84 homology domain-containing) proteins located in the inner nuclear membrane and KASH (Klarsicht/Anc1/Syne1 homology domain-containing) proteins located in the outer nuclear membrane, hence linking nuclear with cytoplasmic structures. While the nucleoplasm-facing side acts as a key player for correct pairing of homolog chromosomes and rapid chromosome movements during meiosis, the cytoplasm-facing side plays a pivotal role for sperm head development and proper acrosome formation during spermiogenesis. A further complex present in spermatozoa is involved in head-to-tail coupling. An intact LINC complex is crucial for the production of fertile sperm, as mutations in genes encoding for complex proteins are known to be associated with male subfertility in both mice and men. The present review provides a comprehensive overview on our current knowledge of LINC complex subtypes present in germ cells and its central role for male reproduction. Future studies on distinct LINC complex components are an absolute requirement to improve the diagnosis of idiopathic male factor infertility and the outcome of assisted reproduction. 相似文献
99.
100.
Staaf E Brehwens K Haghdoost S Pachnerová-Brabcová K Czub J Braziewicz J Nievaart S Wojcik A 《Radiation protection dosimetry》2012,151(3):570-579
Exposure of humans to mixed fields of high- and low-linear energy transfer (LET) radiation occurs in many situations-for example, in urban areas with high levels of indoor radon as well as background gamma radiation, during airplane flights or certain forms of radiation therapy. From the perspective of health risk associated with exposure to mixed fields, it is important to understand the interactions between different radiation types. In most cellular investigations on mixed beams, two types of irradiations have been applied sequentially. Simultaneous irradiation is the desirable scenario but requires a dedicated irradiation facility. The authors have constructed a facility where cells can be simultaneously exposed to (241)Am alpha particles and 190-kV X-rays at 37°C. This study presents the technical details and the dosimetry of the setup, as well as validates the performance of the setup for clonogenic survival in AA8 Chinese hamster ovary cells. No significant synergistic effect was observed. The relative biological effectiveness of the alpha particles was 2.56 for 37 % and 1.90 for 10 % clonogenic survival. 相似文献