全文获取类型
收费全文 | 5432篇 |
免费 | 0篇 |
国内免费 | 1篇 |
专业分类
化学工业 | 19篇 |
建筑科学 | 4篇 |
轻工业 | 2篇 |
无线电 | 4篇 |
一般工业技术 | 5篇 |
冶金工业 | 5393篇 |
原子能技术 | 1篇 |
自动化技术 | 5篇 |
出版年
2014年 | 1篇 |
2013年 | 2篇 |
2011年 | 1篇 |
2009年 | 1篇 |
2006年 | 3篇 |
2004年 | 2篇 |
2003年 | 8篇 |
2000年 | 1篇 |
1999年 | 157篇 |
1998年 | 1646篇 |
1997年 | 893篇 |
1996年 | 638篇 |
1995年 | 324篇 |
1994年 | 313篇 |
1993年 | 330篇 |
1992年 | 36篇 |
1991年 | 57篇 |
1990年 | 77篇 |
1989年 | 65篇 |
1988年 | 62篇 |
1987年 | 82篇 |
1986年 | 58篇 |
1985年 | 57篇 |
1984年 | 1篇 |
1983年 | 11篇 |
1982年 | 30篇 |
1981年 | 34篇 |
1980年 | 39篇 |
1979年 | 1篇 |
1978年 | 8篇 |
1977年 | 143篇 |
1976年 | 336篇 |
1975年 | 10篇 |
1965年 | 1篇 |
1955年 | 5篇 |
排序方式: 共有5433条查询结果,搜索用时 23 毫秒
991.
992.
993.
994.
995.
996.
997.
RJ Harris 《Canadian Metallurgical Quarterly》1976,62(2):287-298
998.
Three hr after i.p. administration of a single dose of 30 mg/kg of morphine to male mice, an increase in specific activity of NADPH-cytochrome c reductase by about 10% and the content of cytochrome P-450 by about 14% of their liver microsomes was observed.Administration of 30 mg/kg of morphine, once daily,during 5 days, caused about 16% and 9% increases in specific activity of c reductase and the content of P-450 respectively. Administration of a single dose of morphine to male and female mice caused no sex-dependent differences in the specific activity of c reductase and the content of P-450. Repeated administration of morphine up to 100 mg/kg to male mice increased the specific activity of microsomal c reductase by about 70%. Repeated administration of morphine up to 55 mg/kg also increased the microsomal content of P-450 by about 22%, but with higher doses of morphine, the content of P-450 declined and finally dropped below control levels. The levels of c-reductase activity and P-450 content returned to normal levels about 2 weeks after termination of morphine administration. 相似文献
999.
1000.
Cryosurgery of bronchopulmonary structures. An approach to lesions inaccessible to the rigid bronchoscope 总被引:1,自引:0,他引:1
Cryonecrosis of the upper lobe of the lung and bronchi was safely inudced in healthy dogs by application of the cryoprobe to serosal surfaces or, through a bronchotomy, to the mucosal surfaces under direct vision. Seven days after cryosurgery, hyperemia of the bronchus was seen. By 14 days the bronchus at the target site was covered with cuboidal epithelium. Reappearance of normal ciliated epithelium occurred by 180 days after cryosurgery. Cartilage remained intact, and there was no evidence of formation of a stricture or other gross alteration of bronchial architecture. In the lung there was coagulation necrosis; and by 14 days after cryosurgery, there was fibrosis in the target area. There were no complications of the pleural space. Cryosurgery of tissues at the margins of the bronchotomy does not impair healing. Cryosurgery may reduce the necessity for extensive surgery in selected patients with bronchopulmonary tumors, including those inaccessible to the rigid bronchoscope. Clinically, eight patients with recurrent bronchogenic tumors have received palliation by transbronchoscopic cryosurgery. 相似文献