全文获取类型
收费全文 | 3026篇 |
免费 | 3篇 |
专业分类
电工技术 | 1篇 |
综合类 | 3篇 |
化学工业 | 10篇 |
建筑科学 | 1篇 |
轻工业 | 5篇 |
水利工程 | 1篇 |
石油天然气 | 2篇 |
无线电 | 1篇 |
一般工业技术 | 5篇 |
冶金工业 | 2993篇 |
自动化技术 | 7篇 |
出版年
2024年 | 1篇 |
2023年 | 1篇 |
2021年 | 1篇 |
2018年 | 1篇 |
2014年 | 2篇 |
2013年 | 1篇 |
2012年 | 5篇 |
2011年 | 2篇 |
2010年 | 1篇 |
2008年 | 4篇 |
2005年 | 3篇 |
2004年 | 1篇 |
2003年 | 5篇 |
2002年 | 1篇 |
2001年 | 1篇 |
1999年 | 88篇 |
1998年 | 885篇 |
1997年 | 492篇 |
1996年 | 314篇 |
1995年 | 169篇 |
1994年 | 148篇 |
1993年 | 171篇 |
1992年 | 25篇 |
1991年 | 35篇 |
1990年 | 38篇 |
1989年 | 45篇 |
1988年 | 53篇 |
1987年 | 54篇 |
1986年 | 35篇 |
1985年 | 33篇 |
1983年 | 11篇 |
1982年 | 14篇 |
1981年 | 20篇 |
1980年 | 38篇 |
1979年 | 4篇 |
1978年 | 12篇 |
1977年 | 93篇 |
1976年 | 215篇 |
1975年 | 6篇 |
1955年 | 1篇 |
排序方式: 共有3029条查询结果,搜索用时 15 毫秒
991.
992.
993.
994.
995.
996.
Renal adenocarcinoma is an infrequent tumor in children. The clinical and radiographic findings in 4 adolescents with such tumors are described. The surgical therapies of these patients and the possible role of adjunctive chemotherapy and radiotherapy are discussed. 相似文献
997.
Measles virus-specific antibodies were isolated from sera, cerebrospinal fluids (CSF), and brain extracts of patients with subacute sclerosing panencephalitis (SSPE) and multiple sclerosis (MS) by absorption with measles antigens and subsequent acid elution of the antigen-antibody precipitates. Electrophoretically homogeneous measles antibodies were isolated from CSF or brain extracts in five patients with SSPE and in five out of seven patients with MS. Homogeneous IgG antibodies were also demonstrated in the sera from all SSPE patients and from three of the MS patients. The antibodies isolated from various control sera and from pooled CSF were electrophoretically heterogeneous. The results support the concept of a local synthesis in the nervous system of oligoclonal IgG antibodies to measles virus in all patients with SSPE and in some patients with MS. In SSPE, most or all oligoclonal IgG proteins of the CSF or brain carry measles antibody activities. In MS, only part of the oligoclonal IgG appears to be associated with measles antibody activity. 相似文献
998.
A study of 100 selected Wisconsin family physicians demonstrated that younger physicians generally had more contact with younger patients, middle-aged physicians had an even distribution of patient age contacts, and older physicians had more contact with older patients. The increase in older patients became pronounced for 56 to 60-year-old physicians. Generally a ten-year increase in physician age was accompanied by a five-year increase in patient age. The rising average age of the American population, combined with the direct physician-patient age relationship demonstrated here suggest that geriatrics will become increasingly relevant not only in the continuum of medical education but also for the individual practicing physician. 相似文献
999.
1000.