全文获取类型
收费全文 | 615篇 |
免费 | 0篇 |
专业分类
综合类 | 1篇 |
化学工业 | 11篇 |
金属工艺 | 1篇 |
轻工业 | 1篇 |
无线电 | 2篇 |
一般工业技术 | 29篇 |
冶金工业 | 566篇 |
原子能技术 | 3篇 |
自动化技术 | 1篇 |
出版年
2022年 | 1篇 |
2017年 | 1篇 |
2014年 | 1篇 |
2013年 | 1篇 |
2011年 | 3篇 |
2010年 | 1篇 |
2007年 | 2篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2000年 | 2篇 |
1999年 | 7篇 |
1998年 | 115篇 |
1997年 | 90篇 |
1996年 | 85篇 |
1995年 | 49篇 |
1994年 | 33篇 |
1993年 | 33篇 |
1992年 | 9篇 |
1991年 | 7篇 |
1990年 | 7篇 |
1989年 | 5篇 |
1988年 | 5篇 |
1987年 | 3篇 |
1986年 | 8篇 |
1985年 | 3篇 |
1984年 | 1篇 |
1983年 | 3篇 |
1982年 | 4篇 |
1981年 | 8篇 |
1980年 | 7篇 |
1979年 | 1篇 |
1978年 | 5篇 |
1977年 | 28篇 |
1976年 | 78篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1965年 | 1篇 |
1955年 | 1篇 |
1954年 | 1篇 |
排序方式: 共有615条查询结果,搜索用时 31 毫秒
11.
Materials Science - Results are presented on the tendency to stress corrosion cracking in NACE solution for welded joints in tube steel with sulfur contents from 0.002 to 0.028%. Threshold stresses... 相似文献
12.
Acute graft rejection and delayed function are considered to be the major risk factors of short-term as well as long-term graft survival. We studied the impact of these factors on graft outcome among 109 renal transplant recipients. All recipients were treated with triple drug protocol. The recipients were divided into two groups: I group included 57 patients with delayed graft function (DGF), II group included 52 patients with immediate graft function (IGF). We studied graft survival, incidence of acute rejection, serum creatinine levels and the cause of graft loss for patients in both groups. Acute rejection episodes occurred in 49% of patients from DGF group and 45% of patients from IGF group. Graft survival in IGF group was better than in DGF group. Actuarial graft survival at 1, 2, 3 and 4 years in examined groups was 84%, 82%, 72%, 65% vs. 92%, 86%, 84%, 84%, respectively. One-year graft survival in patients with acute rejection from DGF group and IGF group was significantly lower than in patients who remained rejection free (69%, 74% vs. 94%, 96%). We concluded that delayed graft function decreases long-term graft survival, while immediate graft function has an excellent impact on graft outcome. Acute graft rejection is the strongest risk factor of graft loss. 相似文献
13.
14.
DM Kulibaba VN Novozhilov EG Tsvetkov VG Medvedev 《Canadian Metallurgical Quarterly》1997,156(2):117-118
Access and visualization in the implant-abutment area are often compromised. Tissue impingement and lack of abutment position verification may result in inaccurate fit. 相似文献
15.
The model of complex formation between polypeptide adopted lefthanded conformation of polyproline II type and minor groove of B-DNA presented. The specific recognition is attained due to possibility of hydrogen bond between Gly NH-group and Thymine O2-group and in addition between Pro CO-group and Guanine NH2-group and between Gly CO-group and Guanine NH2-group. Stereochemical satisfactory of the complex is observed. 相似文献
16.
17.
18.
The article covers complex evaluation of health state in building industry workers engaged into ferro-concrete production in St. Petersburg. The health state was considered under combined action of infrasound, noise and general vibration. Clinical and functional evaluation included medical examination by doctors, blood biochemistry and CBC, ECG, computer integral rheography, voice audiometry. Data for 62 moulders helped to assess acoustic environment at workplace and to reveal the morbidity structure. 相似文献
19.
20.
SB Dennis VG Allen KE Saker JP Fontenot JY Ayad CP Brown 《Canadian Metallurgical Quarterly》1998,76(10):2687-2693
Poor performance of livestock that graze tall fescue (Festuca arundinacea Schreb.) has been associated with the endophyte fungus Neotyphodium coenophialum [Morgan-Jones and Gams] Glenn, Bacon, and Hanlin). Recent evidence suggests lowered Cu status and a depression of Cu-related immune function in steers that graze endophyte-infected (E+) tall fescue. Greenhouse and field studies investigated relationships between the endophyte and Cu concentrations in tall fescue. Seventeen infected 'Kenhy' clones were divided, and one plant of each pair was treated three times with Benomyl to remove the endophyte (E-). Plants were watered with nutrient solution in a greenhouse for 6 mo before sampling. Copper concentrations were greater (P < .001) in E- than in E+ clones (3.4 vs 2.8 microg/g; SE, .06). In the second greenhouse experiment, genetically similar E+ and E- 'Kentucky'-31 (KY-31) and 'Georgia Jessup' were grown from seed and fertilized with nutrient solution to produce mature plants. Copper concentrations were higher (P < .05) in E- than in E+ tall fescue (8.6 vs 7.6 microg/g; SE, .3). In a field plot experiment in Texas, E+ and E- KY-31 were grown with 0, 50, and 100% replacement of potential evapotranspiration. By September, Cu concentrations were higher (P < .05) in E- than in E+ tall fescue (7.3 vs 6.6 microg/g; SE, .2). In pasture experiments, KY-31 E+ (> 70% infection level) and E- (< 5% infection level) tall fescue were grown in Virginia at two locations with three rates of N fertilizer. Copper concentrations were higher (P < .05) in E- than in E+ tall fescue (4.8 vs 4.5 microg/g; SE, .1) and increased (P < .01) linearly in response to N. Our data demonstrate that the presence of the endophyte is associated with lower Cu concentrations in tall fescue, which may contribute to lowered Cu status in animals and thus contribute to the etiology of fescue toxicity. 相似文献