全文获取类型
收费全文 | 434篇 |
免费 | 17篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 35篇 |
化学工业 | 75篇 |
金属工艺 | 9篇 |
机械仪表 | 6篇 |
建筑科学 | 23篇 |
能源动力 | 5篇 |
轻工业 | 34篇 |
水利工程 | 1篇 |
无线电 | 35篇 |
一般工业技术 | 83篇 |
冶金工业 | 110篇 |
自动化技术 | 36篇 |
出版年
2023年 | 7篇 |
2022年 | 6篇 |
2021年 | 6篇 |
2020年 | 3篇 |
2019年 | 2篇 |
2018年 | 2篇 |
2017年 | 6篇 |
2016年 | 12篇 |
2015年 | 13篇 |
2014年 | 9篇 |
2013年 | 17篇 |
2012年 | 12篇 |
2011年 | 16篇 |
2010年 | 14篇 |
2009年 | 15篇 |
2008年 | 7篇 |
2007年 | 11篇 |
2006年 | 8篇 |
2005年 | 6篇 |
2004年 | 16篇 |
2003年 | 8篇 |
2002年 | 12篇 |
2001年 | 5篇 |
2000年 | 23篇 |
1999年 | 12篇 |
1998年 | 42篇 |
1997年 | 17篇 |
1996年 | 17篇 |
1995年 | 11篇 |
1994年 | 8篇 |
1993年 | 9篇 |
1992年 | 8篇 |
1991年 | 9篇 |
1990年 | 4篇 |
1989年 | 7篇 |
1988年 | 9篇 |
1987年 | 6篇 |
1985年 | 7篇 |
1984年 | 3篇 |
1983年 | 5篇 |
1982年 | 5篇 |
1980年 | 5篇 |
1978年 | 4篇 |
1977年 | 2篇 |
1976年 | 5篇 |
1973年 | 2篇 |
1972年 | 4篇 |
1969年 | 2篇 |
1955年 | 2篇 |
1940年 | 1篇 |
排序方式: 共有452条查询结果,搜索用时 0 毫秒
1.
2.
3.
On single-phase B1 molybdenum carbide thin films prepared by the rf sputtering technique at substrate temperatures between 40 and 800°C isochronous annealing and He-irradiation investigations were performed. The transition temperature to superconductivityT
c
,the lattice parametera
0, and the specific resistivity were measured as a function of annealing temperature and fluence, respectively. Both during annealing and irradiation MoC
x
behaves quite differently from typical refractory compounds such as NbC and NbN. During annealingT
c
drops pronouncedly between 250 and 400°C. The B1 structure transforms to -Mo2C between 600 and 900°C. During irradiationT
c
rises slightly and then drops by only 0.5 K. The lattice parametera
0 changes only by 0.2%.On leave of absence from the Institute of Physics, Czechoslovak Academy of Sciences, Prague, Czechoslovakia. 相似文献
4.
Sarah M. Kedziora Kristin Krker Lajos Mark Julia Binder Meryam Sugulle Martin Gauster Dominik N. Müller Ralf Dechend Nadine Haase Florian Herse 《International journal of molecular sciences》2021,22(7)
Preeclampsia (PE) is characterized by the onset of hypertension (≥140/90 mmHg) and presence of proteinuria (>300 mg/L/24 h urine) or other maternal organ dysfunctions. During human PE, renal injuries have been observed. Some studies suggest that women with PE diagnosis have an increased risk to develop renal diseases later in life. However, in human studies PE as a single cause of this development cannot be investigated. Here, we aimed to investigate the effect of PE on postpartum renal damage in an established transgenic PE rat model. Female rats harboring the human-angiotensinogen gene develop a preeclamptic phenotype after mating with male rats harboring the human-renin gene, but are normotensive before and after pregnancy. During pregnancy PE rats developed mild tubular and glomerular changes assessed by histologic analysis, increased gene expression of renal damage markers such as kidney injury marker 1 and connective-tissue growth factor, and albuminuria compared to female wild-type rats (WT). However, four weeks postpartum, most PE-related renal pathologies were absent, including albuminuria and elevated biomarker expression. Only mild enlargement of the glomerular tuft could be detected. Overall, the glomerular and tubular function were affected during pregnancy in the transgenic PE rat. However, almost all these pathologies observed during PE recovered postpartum. 相似文献
5.
I Anderie R Blum W Haase S Grinstein F Thévenod 《Canadian Metallurgical Quarterly》1998,246(2):330-336
We previously characterized a Na+/H+ exchange activity in rat pancreatic zymogen granules [Anderie, I., and Thévenod, F. (1996) J. Membrane Biol, 152, 195-205]. Here we have identified the Na+/H+ exchanger (NHE) isoforms present in zymogen granules by functional studies with NHE inhibitors. The NHE1 specific blocker HOE 694 [3-(methylsulfonyl-4-piperidino-benzoyl)-guanidine methanesulfonate] inhibited zymogen granule Na+/H+ exchange in a concentration dependent manner, maximally to 53 +/- 5% of controls at 100nM. The remaining Na+/H+ exchange activity was inhibitable by EIPA [5-(N-ethyl-N-isopropyl)amiloride] (EC50 approximately 25 microM) or benzamil (EC50 approximately 100 microM). Amiloride inhibited weakly suggesting that "amiloride-resistant" and "amiloride-sensitive" NHE are expressed in zymogen granules. cDNA sequences encoding NHE1- and NHE4-specific transmembrane domains were detected by RT-PCR in rat pancreatic tissue and in the rat pancreatic acinar cell line AR4-2J. The presence of NHE1 and NHE4 in zymogen granule membranes was confirmed by immunoblots of zymogen granule membranes and by pre-embedding immunogold labeling of purified rat pancreatic zymogen granules with polyclonal NHE1 and NHE4 antibodies. Therefore, we propose that NHE1 and NHE4 are expressed in zymogen granule membranes of rat exocrine pancreas. 相似文献
6.
7.
8.
9.
10.
Contribution to the Biosynthesis of High-amylose Pea Starches Biosynthesis of starch is a complex process but few details are still unknown. This paper describes an investigation upon pea starch biosynthesis. Peas as a source of starch offer two qualities, a pea starch with 40% amylose content (smooth pea starch) and a pea starch with more than 60% amylose content (wrinkled pea starch). Samples for analysis were taken during growth. According to the quantitative determination of starch and amylose the accuracy of amylose detection was tested. Furthermore a qualitative analysis was carried out by molecular weight estimation of the starch. Both kinds of peas showed a high amylose synthesis during the last few days of growth, whereas amylopectin synthesis was highly in earlier stages. Wrinkled peas have shown only little synthesis activity of amylopectin during maturity. Therefore the amylose content of these peas was higher, instead of equal amylose synthesis quotas of both smooth and wrinkled peas. 相似文献