全文获取类型
收费全文 | 2278篇 |
免费 | 18篇 |
专业分类
电工技术 | 8篇 |
化学工业 | 88篇 |
金属工艺 | 9篇 |
机械仪表 | 11篇 |
建筑科学 | 41篇 |
能源动力 | 7篇 |
轻工业 | 32篇 |
水利工程 | 11篇 |
无线电 | 33篇 |
一般工业技术 | 144篇 |
冶金工业 | 1834篇 |
原子能技术 | 14篇 |
自动化技术 | 64篇 |
出版年
2023年 | 3篇 |
2021年 | 4篇 |
2020年 | 8篇 |
2018年 | 8篇 |
2017年 | 7篇 |
2016年 | 9篇 |
2015年 | 5篇 |
2014年 | 13篇 |
2013年 | 28篇 |
2012年 | 15篇 |
2011年 | 26篇 |
2010年 | 13篇 |
2009年 | 25篇 |
2008年 | 24篇 |
2007年 | 18篇 |
2006年 | 26篇 |
2005年 | 13篇 |
2004年 | 16篇 |
2003年 | 16篇 |
2002年 | 13篇 |
2001年 | 14篇 |
2000年 | 12篇 |
1999年 | 65篇 |
1998年 | 536篇 |
1997年 | 307篇 |
1996年 | 222篇 |
1995年 | 125篇 |
1994年 | 100篇 |
1993年 | 106篇 |
1992年 | 25篇 |
1991年 | 26篇 |
1990年 | 31篇 |
1989年 | 41篇 |
1988年 | 30篇 |
1987年 | 28篇 |
1986年 | 22篇 |
1985年 | 26篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1982年 | 14篇 |
1981年 | 27篇 |
1980年 | 26篇 |
1979年 | 5篇 |
1978年 | 8篇 |
1977年 | 51篇 |
1976年 | 119篇 |
1975年 | 7篇 |
1974年 | 4篇 |
1955年 | 3篇 |
1954年 | 2篇 |
排序方式: 共有2296条查询结果,搜索用时 281 毫秒
991.
992.
AB Lowenfels 《Canadian Metallurgical Quarterly》1998,338(19):1385; author reply 1385-1385; author reply 1386
993.
994.
AB Dzgoev SA Eremin MV Karpov NP Danilova RG Vasilov AM Egorov 《Canadian Metallurgical Quarterly》1993,19(7):713-721
The influence of the immunogen's tracer's structure on properties of antibodies to phenobarbital was studied by the polarisation fluoroimmunoassay method. It was shown that in homogeneous method of polarisation fluoroimmunoassay the titer of antibodies to phenobarbital (1/1000-1/10,000) is affected by the position of linker binding the antigen with carrier-protein and by the structure of the linker. The affinity constant ((1-4) x 10(9) M-1), cross-reactivity, limit of the detection (0.6-2.6 micrograms/ml) phenobarbital with different combinations of antibodies and tracers were calculated. The antisera grew the more heterogeneous in affinity and specificity, the longer became the linker. The more heterogeneous antibodies are preferable in the class specific assay of barbiturates. 相似文献
995.
The enzyme alpha-amylase from the mould Aspergillus oryzae (Asp o II) routinely used for the production of bread, cakes and pastries has in recent years been identified as an inhalative allergen for occupational diseases (bakers' asthma). It is doubtful whether this amylase in the final product, i.e. after the baking procedure, can still be regarded as an allergen. To clarify this question, detailed case histories on 138 subjects were recorded (98 allergics, 20 patients suffering form chronic intestinal diseases, 20 healthy controls). The clinical examinations included prick skin test and IgE antibody determination using one of the customary enzyme preparations. EAST showed a few of these 138 bread consumers to be weakly sensitized to the enzyme. One of the subjects displayed a significant reaction to alpha-amylase heated to 200 degrees C. As expected, eleven bakers sensitized to alpha-amylase by inhaling it in the workplace (positive prick test, positive case history) predominantly exhibited specific IgE antibodies to the native enzyme. Apart from one weakly positive finding, heated alpha-amylase yielded negative results in this collective. Baking conditions vary widely, especially with regard to single components, temperature and duration. Thus, further investigations as to residual allergenicity or the feasible occurrence of new antigenic determinants during the production of bread, cake and pastries are required. 27% of bakers examined and 9% of atopics showed antibodies to a flour inherent enzyme, a beta-amylase. On the whole, the selected conditions hinted at a weakly sensitizing potential inherent in baking flour and in added amylase. 相似文献
996.
997.
998.
999.
1000.