全文获取类型
收费全文 | 1217篇 |
免费 | 0篇 |
专业分类
电工技术 | 2篇 |
化学工业 | 12篇 |
金属工艺 | 3篇 |
机械仪表 | 5篇 |
矿业工程 | 5篇 |
轻工业 | 2篇 |
水利工程 | 2篇 |
石油天然气 | 8篇 |
无线电 | 4篇 |
一般工业技术 | 18篇 |
冶金工业 | 1149篇 |
原子能技术 | 2篇 |
自动化技术 | 5篇 |
出版年
2022年 | 2篇 |
2021年 | 3篇 |
2020年 | 2篇 |
2015年 | 2篇 |
2013年 | 4篇 |
2011年 | 3篇 |
2010年 | 3篇 |
2009年 | 3篇 |
2007年 | 2篇 |
2006年 | 3篇 |
2005年 | 1篇 |
2004年 | 2篇 |
2003年 | 1篇 |
2002年 | 1篇 |
2000年 | 3篇 |
1999年 | 5篇 |
1998年 | 273篇 |
1997年 | 204篇 |
1996年 | 161篇 |
1995年 | 86篇 |
1994年 | 73篇 |
1993年 | 60篇 |
1992年 | 14篇 |
1991年 | 13篇 |
1990年 | 1篇 |
1989年 | 10篇 |
1988年 | 7篇 |
1987年 | 3篇 |
1986年 | 4篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 9篇 |
1981年 | 10篇 |
1980年 | 19篇 |
1979年 | 2篇 |
1978年 | 4篇 |
1977年 | 71篇 |
1976年 | 124篇 |
1975年 | 4篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1972年 | 1篇 |
1971年 | 2篇 |
1970年 | 2篇 |
1969年 | 1篇 |
1968年 | 3篇 |
1967年 | 1篇 |
1960年 | 1篇 |
1955年 | 2篇 |
排序方式: 共有1217条查询结果,搜索用时 15 毫秒
41.
42.
43.
44.
Cytogenetic study conducted after a single intraperitoneal injection of cyclophosphane in doses of 10, 20, and 40 mg/kg showed in 1.5-2-month-old male mice that the level of bone marrow cells damaged by the mutagen was significantly higher in NZW animals than in C57Bl/6 animals. The ability to produce active oxygen forms in response to addition of opsonized zymosan and phorbol myristate acetate was also higher in bone marrow suspensions of NZW mice. The higher sensitivity of NZW animals to pro-oxidant and clastogenic effects may be related to the genetically determined decrease of antioxidant protection in NZW animals. 相似文献
45.
The known literature data concerning the mechanisms of molecular action of vitamin E in biological membrane systems are reviewed. The role of vitamin E, possessing a broad range of biological activities, as a universal stabilizer of biological membranes in normal oxygen metabolism and peroxidation, and also in disorders of normal metabolism resulting in pathological alterations, has been discussed. The participation of vitamin E in redox reactions taking place in lipid media, its interaction with singlet oxygen, free fatty acids and enzyme systems are considered. Physiological effects of vitamin E and its ability to prevent numerous pathologies are also considered. Vitamin E was concluded to be a universal participant of antioxidant defence reactions in biological membranes, since it acts at all stages of membrane oxidative damage. 相似文献
46.
AV Sidorov VV Zverev AG Zdanovski? AV Pugach VV Maliushova OG Andzhaparidze 《Canadian Metallurgical Quarterly》1994,39(1):6-10
Lack of uniformity in the classification of oral diseases, and variability of study designs, measurements, methods, and statistical formats, hamper the interpretation, comparison and review of the evidence linking smoking and oral diseases. However, there have been a significant number of controlled studies, allowing definitive conclusions to be drawn. This review of 22 controlled scientific studies from 1983-1992, considers the role of smoking as an aetiological agent in: gingival problems (impaired gingival bleeding, ANUG), periodontal problems (periodontitis, bone loss, tooth loss), and caries. 相似文献
47.
48.
An opticoelectronic system for measurement of a surface microprofile and elasticity of the skin in real time has been developed operating with a source of radiation having small time coherence. The frequency of measurement is 120 Hz, accuracy at least 3 microns. The system can be used for anthropological inspections, study of age and pathological changes in the skin. 相似文献
49.
AG Kats VV Afanas'ev IaM Biberman IF Romacheva VS Starodubtsev MB Shvyrkov 《Canadian Metallurgical Quarterly》1998,77(4):67-68
Analysis of the results of examinations in oral surgery making use of tests in 319 fourth-year students showed that such a method of assessing students' knowledge is highly objective. 相似文献
50.