全文获取类型
收费全文 | 393篇 |
免费 | 0篇 |
国内免费 | 2篇 |
专业分类
综合类 | 1篇 |
化学工业 | 7篇 |
机械仪表 | 2篇 |
建筑科学 | 1篇 |
能源动力 | 1篇 |
轻工业 | 2篇 |
无线电 | 4篇 |
一般工业技术 | 2篇 |
冶金工业 | 367篇 |
自动化技术 | 8篇 |
出版年
2019年 | 2篇 |
2013年 | 3篇 |
2010年 | 1篇 |
2007年 | 1篇 |
2006年 | 1篇 |
2004年 | 1篇 |
2003年 | 5篇 |
2002年 | 3篇 |
2000年 | 1篇 |
1999年 | 7篇 |
1998年 | 114篇 |
1997年 | 60篇 |
1996年 | 36篇 |
1995年 | 26篇 |
1994年 | 18篇 |
1993年 | 15篇 |
1992年 | 1篇 |
1991年 | 3篇 |
1990年 | 6篇 |
1989年 | 4篇 |
1988年 | 7篇 |
1987年 | 4篇 |
1986年 | 7篇 |
1985年 | 5篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1977年 | 22篇 |
1976年 | 28篇 |
1975年 | 2篇 |
1968年 | 1篇 |
1964年 | 1篇 |
排序方式: 共有395条查询结果,搜索用时 0 毫秒
391.
392.
Normal rats were treated with pregnenolone- 16alpha - carbonitrile (PCN) 10 mg/100 g by stomach tube twice daily for 3 days. In these animals the biliary excretion of intravenously injected 125I-thyroxine (T4) was enhanced and the bile: plasma 125I ratio (B/P ratio) and the biliary clearance rate of plasma 125I-T4 was increased. Normal rats were treated with PCN for 3 days and homozygous Gunn rats for 13 days. In both groups PCN enhanced the bile flow and elevated the B/P ratios and the biliary clearance rate of plasma T4 following ip injection of 125I-T4 17 h previously. PCN-treatment had no effect on the fractions of biliary 125I present as T4-glucuronide, T4 and I- in either the normal or Gunn rats. Treatment with PCN for 10 days produced goitres in normal and Gunn rats and in normal rats elevated the serum TSH (bioassay) levels and the 17 h thyroid 131I uptake as well as the serum PB125I concentrations, without affecting stable PBI concentrations. These data indicated increased pituitary TSH release in response to increased peripheral metabolism of thyroid hormone; enhanced hormonal release from the thyroid kept pace with the accelerated peripheral loss. 相似文献
393.
D Flego M Pirhonen H Saarilahti TK Palva ET Palva 《Canadian Metallurgical Quarterly》1997,25(5):831-838
1. The authors performed both microdialysis and behavioral measurement in each of rats, in order to examine effects of nitric oxide synthase inhibitor, N omega-nitro-L-arginine methyl ester (LNAME;30 mg/kg,i.p.) on striatal dopamine (DA) release and stereotypy induced by a single administration of methamphetamine (MA)(4 mg/kg,s.c.), simultaneously. 2. LNAME administered prior to MA significantly decreased level of locomotion-stereotypy rating scores induced by MA. 3. In the same animals, LNAME had no effect on MA-induced striatal DA release. 4. The results suggest that NO synthesis inhibition attenuated MA-induced stereotypy by modulating neuronal process subsequent to activation of postsynaptic DA receptors. 相似文献
394.
The interaction of Co (30 nm) thin films on Si (100) substrate in UHV using solid state mixing technique has been studied. Cobalt was deposited on silicon substrate using electron beam evaporation at a vacuum of 4×10?8 Torr having a deposition rate of about 0·1 Å/s. Reactivity at Co/Si interface is important for the understanding of silicide formation in thin film system. In the present paper, cobalt silicide films were characterized by atomic force microscopy (AFM) and secondary ion mass spectroscopy (SIMS) in terms of the surface and interface morphologies and depth profile, respectively. The roughness of the samples was found to increase up to temperature, 300°C and then decreased with further rise in temperature, which was due to the formation of crystalline CoSi2 phase. The effect of mixing on magnetic properties such as coercivity, remanence etc at interface has been studied using magneto optic Kerr effect (MOKE) techniques at different temperatures. The value of coercivity of pristine sample and 300°C annealed sample was found to be 66 Oe and 40 Oe, respectively, while at high temperature i.e. 748°C, the hysteresis disappears which indicates the formation of CoSi2 compound. 相似文献
395.
A field experiment was conducted on an alkali soil to evaluate the direct and the residual effect of six levels of zinc i.e. 0, 2.25, 4.5, 9.0, 18.0 and 27.0 kg Zn ha–1 added either once to the first crop only or continuously to each crop on the growth, yield and chemical composition of plants grown in a rice-wheat cropping sequence. The soils were amended with gypsum applied at the uniform rate of 14 t ha–1. Zinc was supplied as zinc sulphate. Application of zinc at the rate of 2.25 kg ha–1 to both rice and wheat crops or an annual application of 4.5 kg Zn ha–1 only to rice was found optimum for rice-wheat sequence. Higher zinc applications increased the availability of zinc in the soil and its content in the plants but did not increase crop yield. DTPA extractable zinc build up was more for zinc applied at the rate of 2.25 kg ha–1 to each crop compared to a single zinc application of equivalent amount. Results of these studies have shown that continuous Zn application up to 27 kg Zn ha–1 to each crop did not induce nutrient imbalances and had no adverse effect on crop yield. 相似文献