全文获取类型
| 收费全文 | 416篇 |
| 免费 | 17篇 |
| 国内免费 | 10篇 |
专业分类
| 电工技术 | 3篇 |
| 综合类 | 17篇 |
| 化学工业 | 156篇 |
| 机械仪表 | 6篇 |
| 建筑科学 | 14篇 |
| 能源动力 | 30篇 |
| 轻工业 | 67篇 |
| 水利工程 | 15篇 |
| 石油天然气 | 1篇 |
| 无线电 | 45篇 |
| 一般工业技术 | 47篇 |
| 冶金工业 | 11篇 |
| 原子能技术 | 4篇 |
| 自动化技术 | 27篇 |
出版年
| 2024年 | 14篇 |
| 2023年 | 18篇 |
| 2022年 | 51篇 |
| 2021年 | 51篇 |
| 2020年 | 24篇 |
| 2019年 | 11篇 |
| 2018年 | 16篇 |
| 2017年 | 10篇 |
| 2016年 | 14篇 |
| 2015年 | 11篇 |
| 2014年 | 20篇 |
| 2013年 | 20篇 |
| 2012年 | 20篇 |
| 2011年 | 14篇 |
| 2010年 | 10篇 |
| 2009年 | 15篇 |
| 2008年 | 10篇 |
| 2007年 | 15篇 |
| 2006年 | 20篇 |
| 2005年 | 14篇 |
| 2004年 | 12篇 |
| 2003年 | 3篇 |
| 2002年 | 1篇 |
| 2001年 | 11篇 |
| 2000年 | 3篇 |
| 1999年 | 2篇 |
| 1998年 | 7篇 |
| 1997年 | 5篇 |
| 1996年 | 2篇 |
| 1995年 | 4篇 |
| 1994年 | 2篇 |
| 1993年 | 3篇 |
| 1989年 | 2篇 |
| 1988年 | 1篇 |
| 1986年 | 3篇 |
| 1984年 | 1篇 |
| 1983年 | 2篇 |
| 1979年 | 1篇 |
排序方式： 共有443条查询结果，搜索用时 0 毫秒
381.
382.
Jana Knoppov Jianfeng Yu Jan Janou&#x;kovec Petr Halada Peter J. Nixon Julian P. Whitelegge Josef Komenda 《International journal of molecular sciences》2021,22(7)
Photochemical energy conversion during oxygenic photosynthesis is performed by membrane-embedded chlorophyll-binding protein complexes. The biogenesis and maintenance of these complexes requires auxiliary protein factors that optimize the assembly process and protect nascent complexes from photodamage. In cyanobacteria, several lipoproteins contribute to the biogenesis and function of the photosystem II (PSII) complex. They include CyanoP, CyanoQ, and Psb27, which are all attached to the lumenal side of PSII complexes. Here, we show that the lumenal Ycf48 assembly factor found in the cyanobacterium Synechocystis sp. PCC 6803 is also a lipoprotein. Detailed mass spectrometric analysis of the isolated protein supported by site-directed mutagenesis experiments indicates lipidation of the N-terminal C29 residue of Ycf48 and removal of three amino acids from the C-terminus. The lipobox sequence in Ycf48 contains a cysteine residue at the −3 position compared to Leu/Val/Ile residues found in the canonical lipobox sequence. The atypical Ycf48 lipobox sequence is present in most cyanobacteria but is absent in eukaryotes. A possible role for lipoproteins in the coordinated assembly of cyanobacterial PSII is discussed. 相似文献
383.
Monika Kula-Maximenko Kamil Jan Zieli&#x;ski Ireneusz
lesak 《International journal of molecular sciences》2021,22(8)
Gloeobacter violaceus is a cyanobacteria species with a lack of thylakoids, while photosynthetic antennas, i.e., phycobilisomes (PBSs), photosystem II (PSII), and I (PSI), are located in the cytoplasmic membrane. We verified the hypothesis that blue–red (BR) light supplemented with a far-red (FR), ultraviolet A (UVA), and green (G) light can affect the photosynthetic electron transport chain in PSII and explain the differences in the growth of the G. violaceus culture. The cyanobacteria were cultured under different light conditions. The largest increase in G. violaceus biomass was observed only under BR + FR and BR + G light. Moreover, the shape of the G. violaceus cells was modified by the spectrum with the addition of G light. Furthermore, it was found that both the spectral composition of light and age of the cyanobacterial culture affect the different content of phycobiliproteins in the photosynthetic antennas (PBS). Most likely, in cells grown under light conditions with the addition of FR and G light, the average antenna size increased due to the inactivation of some reaction centers in PSII. Moreover, the role of PSI and gloeorhodopsin as supplementary sources of metabolic energy in the G. violaceus growth is discussed. 相似文献
384.
Linxuan Li Tingting Zhu Lele Huang Maozhi Ren 《International journal of molecular sciences》2022,23(13)
Target of rapamycin (TOR) is a serine/threonine protein kinase that plays a central regulating role in cell proliferation, growth, and metabolism, but little is known about the TOR signaling pathway in Chlorella sorokiniana. In this study, a Chlorella sorokiniana DP-1 strain was isolated and identified, and its nutritional compositions were analyzed. Based on homologous sequence analysis, the conserved CsTOR protein was found in the genome of Chlorella sorokiniana. In addition, the key components of TOR complex 1 (TORC1) were present, but the components of TORC2 (RICTOR and SIN1) were absent in Chlorella sorokiniana. Pharmacological assays showed that Chlorella sorokiniana DP-1 was insensitive to rapamycin, Torin1 and KU0063794, whereas AZD8055 could significantly inhibit the growth of Chlorella sorokiniana. RNA-seq analysis showed that CsTOR regulated various metabolic processes and signal transduction pathways in AZD8055-treated Chlorella sorokiniana DP-1. Most genes involved in photosynthesis and carbon fixation in Chlorella sorokiniana DP-1 were significantly downregulated under CsTOR inhibition, indicating that CsTOR positively regulated the photosynthesis in Chlorella sorokiniana. Furthermore, CsTOR controlled protein synthesis and degradation by positively regulating ribosome synthesis and negatively regulating autophagy. These observations suggested that CsTOR plays an important role in photosynthesis and cellular metabolism, and provide new insights into the function of CsTOR in Chlorella sorokiniana. 相似文献
385.
386.
387.
Jianqiang Wu Mengliang Zhu Weikang Liu Mohammad Shah Jahan Qinsheng Gu Sheng Shu Jin Sun Shirong Guo 《International journal of molecular sciences》2022,23(20)
Polyamine oxidases (PAOs) are key enzymes in polyamine metabolism and are related to the tolerance of plants to abiotic stresses. In this study, overexpression of cucumber (Cucumis sativus L.) PAO2 (CsPAO2) in Arabidopsis resulted in increased activity of the antioxidant enzyme and accelerated conversion from Put to Spd and Spm, while malondialdehyde content (MDA) and electrolyte leakage (EL) was decreased when compared with wild type, leading to enhanced plant growth under salt stress. Photosystem Ⅰ assembly 3 in cucumber (CsPSA3) was revealed as an interacting protein of CsPAO2 by screening yeast two-hybrid library combined with in vitro and in vivo methods. Then, CsPAO2 and CsPSA3 were silenced in cucumber via virus-mediated gene silencing (VIGS) with pV190 as the empty vector. Under salt stress, net photosynthetic rate (Pn) and transpiration rate (Tr) of CsPAO2-silencing plants were lower than pV190-silencing plants, and EL in root was higher than pV190-silencing plants, indicating that CsPAO2-silencing plants suffered more serious salt stress damage. However, photosynthetic parameters of CsPSA3-silencing plants were all higher than those of CsPAO2 and pV190-silencing plants, thereby enhancing the photosynthesis process. Moreover, CsPSA3 silencing reduced the EL in both leaves and roots when compared with CsPAO2-silencing plants, but the EL only in leaves was significantly lower than the other two gene-silencing plants, and conversion from Put to Spd and Spm in leaf was also promoted, suggesting that CsPSA3 interacts with CsPAO2 in leaves to participate in the regulation of salt tolerance through photosynthesis and polyamine conversion. 相似文献
388.
Miroslav Krausko Zuzana Kus Darina Peterkov Mria Labajov Ajay Kumar Andrej Pavlovi
Michaela Ba
ov
inov Martin Ba
kor Jn Jsik 《International journal of molecular sciences》2022,23(3)
Arabidopsis thaliana SYNAPTOTAGMIN 1 (AtSYT1) was shown to be involved in responses to different environmental and biotic stresses. We investigated gas exchange and chlorophyll a fluorescence in Arabidopsis wild-type (WT, ecotype Col-0) and atsyt1 mutant plants irrigated for 48 h with 150 mM NaCl. We found that salt stress significantly decreases net photosynthetic assimilation, effective photochemical quantum yield of photosystem II (ΦPSII), stomatal conductance and transpiration rate in both genotypes. Salt stress has a more severe impact on atsyt1 plants with increasing effect at higher illumination. Dark respiration, photochemical quenching (qP), non-photochemical quenching and ΦPSII measured at 750 µmol m−2 s−1 photosynthetic photon flux density were significantly affected by salt in both genotypes. However, differences between mutant and WT plants were recorded only for qP and ΦPSII. Decreased photosynthetic efficiency in atsyt1 under salt stress was accompanied by reduced chlorophyll and carotenoid and increased flavonol content in atsyt1 leaves. No differences in the abundance of key proteins participating in photosynthesis (except PsaC and PsbQ) and chlorophyll biosynthesis were found regardless of genotype or salt treatment. Microscopic analysis showed that irrigating plants with salt caused a partial closure of the stomata, and this effect was more pronounced in the mutant than in WT plants. The localization pattern of AtSYT1 was also altered by salt stress. 相似文献
389.
Jae-Yeon Joo Me-Sun Kim Yong-Gu Cho Alisdair R. Fernie Jwakyung Sung 《International journal of molecular sciences》2022,23(16)
The ever-increasing human population alongside environmental deterioration has presented a pressing demand for increased food production per unit area. As a consequence, considerable research effort is currently being expended in assessing approaches to enhance crop yields. One such approach is to harness the allelic variation lost in domestication. This is of particular importance since crop wild relatives often exhibit better tolerance to abiotic stresses. Here, we wanted to address the question as to why wild rice species have decreased grain production despite being characterized by enhanced rates of photosynthesis. In order to do so, we selected ten rice species on the basis of the presence of genome information, life span, the prominence of distribution, and habitat type and evaluated the expression of genes in photosynthesis, photorespiration, sucrose and starch synthesis, sucrose transport, and primary and secondary cell walls. We additionally measured the levels of a range of primary metabolites via gas chromatography–mass spectrometry. The results revealed that the wild rice species exhibited not only higher photosynthesis but also superior CO2 recovery by photorespiration; showed greater production of photosynthates such as soluble sugars and starch and quick transportation to the sink organs with a possibility of transporting forms such as RFOs, revealing the preferential consumption of soluble sugars to develop both primary and secondary cell walls; and, finally, displayed high glutamine/glutamic acid ratios, indicating that they likely exhibited high N-use efficiency. The findings from the current study thus identify directions for future rice improvement through breeding. 相似文献
390.