全文获取类型
收费全文 | 224篇 |
免费 | 14篇 |
国内免费 | 6篇 |
专业分类
电工技术 | 13篇 |
综合类 | 9篇 |
化学工业 | 6篇 |
金属工艺 | 3篇 |
机械仪表 | 4篇 |
建筑科学 | 22篇 |
矿业工程 | 12篇 |
能源动力 | 3篇 |
轻工业 | 12篇 |
水利工程 | 2篇 |
石油天然气 | 19篇 |
武器工业 | 1篇 |
无线电 | 4篇 |
一般工业技术 | 5篇 |
冶金工业 | 118篇 |
原子能技术 | 4篇 |
自动化技术 | 7篇 |
出版年
2023年 | 2篇 |
2022年 | 3篇 |
2021年 | 3篇 |
2020年 | 6篇 |
2019年 | 6篇 |
2018年 | 2篇 |
2017年 | 2篇 |
2016年 | 4篇 |
2015年 | 3篇 |
2014年 | 6篇 |
2013年 | 6篇 |
2012年 | 7篇 |
2011年 | 39篇 |
2010年 | 21篇 |
2009年 | 12篇 |
2008年 | 15篇 |
2007年 | 17篇 |
2006年 | 17篇 |
2005年 | 10篇 |
2004年 | 11篇 |
2003年 | 11篇 |
2002年 | 9篇 |
2001年 | 8篇 |
1999年 | 3篇 |
1998年 | 5篇 |
1997年 | 3篇 |
1996年 | 2篇 |
1993年 | 1篇 |
1990年 | 2篇 |
1989年 | 3篇 |
1988年 | 1篇 |
1977年 | 1篇 |
1970年 | 1篇 |
1963年 | 1篇 |
1956年 | 1篇 |
排序方式: 共有244条查询结果,搜索用时 31 毫秒
1.
《Planning》2019,(6)
减少手术创伤始终是快速康复的决定性因素,这一点在目前的加速康复外科研究尤其是复杂手术,如妇科肿瘤手术中尚未得到充分重视。尊重学习曲线、全面规划手术方案、总结失利经验、开展前瞻性研究是解决此问题的主要方案。本文着重讨论妇科肿瘤手术创伤对术后加速康复的影响及可能的改进措施。 相似文献
2.
巴林左旗是内蒙古赤峰市重要的铅锌多金属矿产的产区,通过对碧流台村北铅锌矿区域地质背景、成矿地质特征、物化探异常特征、矿体特征等因素的综合分析,总结了碧流台村北铅锌矿成矿地质条件、找矿标志及矿床成因,同时对矿区进行了远景预测,认为矿区深部具有寻找中型铅锌盲矿体的潜力,对矿区下一步找矿工作具有重要的指导意义。 相似文献
3.
莫桑比克作为全球重要的前寒武纪变质单元之一,是冈瓦纳古陆重要的组成部分。对其基础地质研究过程从19世纪初至今主要经历了4个阶段,本世纪初至今新理论和新方法的应用使得其基础地质研究得到飞跃发展。莫桑比克的前寒武纪地质单元可划分为津巴布韦-马尼卡克拉通基底、莫桑比克构造带及伊鲁米德构造带3个部分,其每部分又可进一步细分不同的构造单元(细化)。结合地质特征及矿产分布情况明确了莫桑比克的优势矿产资源为天然气、煤、钛、金、钽及石墨等矿种。莫桑比克可划分为北赞比西河成矿省、津巴布韦克拉通边界-巴鲁埃杂岩成矿省、乌南戈-利欣加成矿省、莫桑比克带-鲁伍马-赞比西成矿带省等四大成矿省和21个具有找矿前景的多金属成矿远景区。本文详细地划分了莫桑比克前寒武纪重要成矿区带并分析其成矿地质条件,结合近年来的矿产勘查工作认识,系统梳理了莫桑比克前寒武纪重要成矿区带的成矿条件和规律,重点总结了优势矿种的成矿特征,为莫桑比克矿业投资提供参考,并针对开展莫桑比克重要战略矿产的投资提供依据。 相似文献
4.
5.
6.
7.
Giuseppe Grosso Stefano Marventano Justin Yang Agnieszka Micek Andrzej Pajak Luca Scalfi 《Critical reviews in food science and nutrition》2017,57(15):3218-3232
Many studies have reported that higher adherence to Mediterranean diet may decrease cardiovascular disease (CVD) incidence and mortality. We performed a meta-analysis to explore the association in prospective studies and randomized control trials (RCTs) between Mediterranean diet adherence and CVD incidence and mortality. The PubMed database was searched up to June 2014. A total of 17 studies were extracted and 11 qualified for the quantitative analysis. Individuals in the highest quantile of adherence to the diet had lower incidence [relative risk (RR): 0.76, 95% confidence intervals (CI): 0.68, 0.83] and mortality (RR: 0.76, 95% CI: 0.68, 0.83) from CVD compared to those least adherent. A significant reduction of risk was found also for coronary heart disease (CHD) (RR: 0.72, 95% CI: 0.60, 0.86), myocardial infarction (MI) (RR: 0.67; 95% CI: 0.54, 0.83), and stroke (RR: 0.76; 95% CI: 0.60, 0.96) incidence. Pooled analyses of individual components of the diet revealed that the protective effects of the diet appear to be most attributable to olive oil, fruits, vegetables, and legumes. An average reduced risk of 40% for the aforementioned outcomes has been retrieved when pooling results of RCTs. A Mediterranean dietary pattern is associated with lower risks of CVD incidence and mortality, including CHD and MI. The relative effects of specific food groups should be further investigated. 相似文献
8.
Taylor H. Gerry; Dietrich Ann; Nuss Kathryn; Wright Martha; Rusin Jerome; Bangert Barbara; Minich Nori; Yeates Keith Owen 《Canadian Metallurgical Quarterly》2010,24(2):148
To investigate postconcussive symptoms (PCS) following pediatric mild traumatic brain injury (mTBI), 8- to 15-year-old children with mTBI (n = 186) and a comparison group with uncomplicated orthopedic injuries (OI, n = 99) were recruited from two emergency departments. Parent and child ratings of PCS and symptom counts were obtained within 3 weeks after injury (baseline) and at 1, 3, and 12 months postinjury. The mTBI group also completed magnetic resonance imaging at baseline. Group differences were examined using growth modeling, controlling for age at injury, sex, socioeconomic status, and (for parent-based measures) preinjury symptom levels. Relative to the OI group, the mTBI group had higher ratings of somatic PCS and parent counts of PCS at the initial assessments, but higher parent ratings of cognitive PCS and child counts of PCS throughout follow-up. Higher levels of PCS in the mTBI group were associated with motor-vehicle-related trauma, loss of consciousness, neuroimaging abnormalities, and hospitalization. The findings validate both transient and persistent PCS in children with mTBI and document associations of symptoms with injury and noninjury factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
Schmitter-Edgecombe Maureen; Woo Ellen; Greeley David R. 《Canadian Metallurgical Quarterly》2009,23(2):168
The authors evaluated multiple memory processes and explored their contributions to everyday functional limitations in persons with mild cognitive impairment (MCI). Participants included individuals with amnestic MCI, nonamnestic MCI, and healthy older adults. As expected, the amnestic MCI group performed more poorly than the control and nonamnestic MCI groups on a content memory measure. Both MCI groups, however, performed more poorly than controls on the noncontent memory measures of prospective memory, temporal order memory, and source memory. Informants also reported that the MCI groups were experiencing greater difficulty than controls completing instrumental activities of daily living (IADLs). Noncontent memory measures were found to make an independent contribution to IADL performances over and above that of content memory. These findings demonstrate that impairments in memory beyond the traditionally assessed content memory are present in individuals with amnestic MCI and with nonamnestic MCI. The results further show that these noncontent memory processes, which have been linked with executive functioning, play a role in supporting IADLs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
王小堡-东庙岭-金鸡背这一辽东清原金富集带,已往以寻找石英脉型金矿为主。近两年来,笔者通过在该区进行的实地工作及与东北大学专家教授联合攻关,确认了此金富集带为一典型的含金韧性剪切带,同时总结归纳出各种金成矿类型及其特征,其中蚀变岩型金矿尤为重要,并将其与吉林六批叶大型韧性剪切带中的蚀变岩型金矿加以类比,在此基础上对该区域找矿远景提出评述。 相似文献