全文获取类型
收费全文 | 9587篇 |
免费 | 120篇 |
国内免费 | 7篇 |
专业分类
电工技术 | 76篇 |
综合类 | 5篇 |
化学工业 | 1099篇 |
金属工艺 | 114篇 |
机械仪表 | 245篇 |
建筑科学 | 238篇 |
矿业工程 | 33篇 |
能源动力 | 189篇 |
轻工业 | 563篇 |
水利工程 | 48篇 |
石油天然气 | 11篇 |
武器工业 | 2篇 |
无线电 | 644篇 |
一般工业技术 | 1176篇 |
冶金工业 | 4514篇 |
原子能技术 | 118篇 |
自动化技术 | 639篇 |
出版年
2021年 | 66篇 |
2020年 | 49篇 |
2019年 | 54篇 |
2018年 | 60篇 |
2017年 | 70篇 |
2016年 | 71篇 |
2015年 | 60篇 |
2014年 | 105篇 |
2013年 | 239篇 |
2012年 | 161篇 |
2011年 | 256篇 |
2010年 | 185篇 |
2009年 | 191篇 |
2008年 | 217篇 |
2007年 | 211篇 |
2006年 | 223篇 |
2005年 | 158篇 |
2004年 | 169篇 |
2003年 | 163篇 |
2002年 | 147篇 |
2001年 | 151篇 |
2000年 | 150篇 |
1999年 | 250篇 |
1998年 | 1325篇 |
1997年 | 749篇 |
1996年 | 557篇 |
1995年 | 335篇 |
1994年 | 286篇 |
1993年 | 335篇 |
1992年 | 125篇 |
1991年 | 130篇 |
1990年 | 122篇 |
1989年 | 129篇 |
1988年 | 110篇 |
1987年 | 107篇 |
1986年 | 117篇 |
1985年 | 120篇 |
1984年 | 105篇 |
1983年 | 92篇 |
1982年 | 89篇 |
1981年 | 133篇 |
1980年 | 126篇 |
1979年 | 93篇 |
1978年 | 88篇 |
1977年 | 176篇 |
1976年 | 343篇 |
1975年 | 79篇 |
1974年 | 47篇 |
1973年 | 69篇 |
1972年 | 46篇 |
排序方式: 共有9714条查询结果,搜索用时 15 毫秒
51.
The absolute right to refuse medical treatment, even if the reasons are irrational, is confined to competent adults. Children under 16 years can give legal consent to treatment in the absence of consent from those with parental responsibility. Children under 18 years do not, however, have an absolute right to consent, or refuse to consent, to treatment. The views of children assume increasing importance with age and maturity. Accident and emergency medical and nursing staff may face difficult decisions when children, or those with parental responsibility, refuse to consent to medical treatment. This paper presents guidelines designed to guide the decision making process in immediately or potentially life threatening conditions and in non-life-threatening conditions. 相似文献
52.
53.
54.
Jennings Jerry L.; Williams Charles; Thompson-Owens Margie 《Canadian Metallurgical Quarterly》1994,31(4):700
Presents a model for conceptualizing 4 basic types of suicidality among substance abusers (avoidance of painful consequences, the depressive experience of "crashing," the threat of personal loss, and environmental strain) and offers practical tips for treating the problem. Four general forms of intervention are discussed: pacing the crisis encounter; desensitizing the patient's sense of desperation; talking frankly about the suicidality; and attending to one's own needs as a counselor. These crisis-intervention tips are intended to aid counselors in handling suicidality as it is manifested in substance-abusing populations. Tips and guidelines for suicidal risk assessment with drug and alcohol abusers are given. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
56.
57.
58.
59.
J. A. Hunt A. Remes D. F. Williams 《Journal of materials science. Materials in medicine》1992,3(3):192-198
This study examined neutrophil activation, after incubation of these cells with metal ions. Activation was examined using lysozyme and chemiluminescence assays. Cobalt ions (0.5–30 p.p.m.), chromium ions (0.5–20 p.p.m.), nickel ions (1–50 p.p.m.) and aluminium ions (0.05–7.5 p.p.m.) did not stimulate neutrophils to release lysozyme and did not stimulate a respiratory burst. Copper ions (0.25–7.5 p.p.m.) stimulated neutrophils to release lysozyme, a result which was significant at the 5% level. This was not as a result of copper ions causing neutrophils to lyse. Lysozyme secretion was inhibited when neutrophils were pre-incubated with cytochalasin B, although cytochalasin B had no effect on the enzyme secretion due to stimulation by opsonized zymosan and zymosan-activated serum. This suggests that the mechanism by which copper ions stimulate neutrophil degranulation is different from that of opsonized zymosan and zymosan-activated serum. Enzyme secretion was not accompanied by a respiratory burst. 相似文献
60.