全文获取类型
收费全文 | 1305篇 |
免费 | 105篇 |
国内免费 | 163篇 |
专业分类
电工技术 | 10篇 |
综合类 | 50篇 |
化学工业 | 77篇 |
金属工艺 | 135篇 |
机械仪表 | 23篇 |
建筑科学 | 371篇 |
矿业工程 | 3篇 |
能源动力 | 12篇 |
轻工业 | 595篇 |
水利工程 | 1篇 |
石油天然气 | 1篇 |
武器工业 | 1篇 |
无线电 | 119篇 |
一般工业技术 | 20篇 |
冶金工业 | 32篇 |
原子能技术 | 103篇 |
自动化技术 | 20篇 |
出版年
2024年 | 2篇 |
2023年 | 23篇 |
2022年 | 32篇 |
2021年 | 44篇 |
2020年 | 38篇 |
2019年 | 86篇 |
2018年 | 51篇 |
2017年 | 111篇 |
2016年 | 90篇 |
2015年 | 69篇 |
2014年 | 139篇 |
2013年 | 89篇 |
2012年 | 63篇 |
2011年 | 100篇 |
2010年 | 78篇 |
2009年 | 46篇 |
2008年 | 94篇 |
2007年 | 39篇 |
2006年 | 42篇 |
2005年 | 62篇 |
2004年 | 40篇 |
2003年 | 11篇 |
2002年 | 24篇 |
2001年 | 23篇 |
2000年 | 23篇 |
1999年 | 8篇 |
1998年 | 17篇 |
1997年 | 11篇 |
1996年 | 7篇 |
1995年 | 11篇 |
1994年 | 3篇 |
1993年 | 6篇 |
1992年 | 9篇 |
1991年 | 8篇 |
1990年 | 28篇 |
1989年 | 8篇 |
1988年 | 9篇 |
1987年 | 9篇 |
1986年 | 7篇 |
1985年 | 6篇 |
1984年 | 4篇 |
1983年 | 1篇 |
1981年 | 2篇 |
排序方式: 共有1573条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
大鼠白蛋白的相对分子质量约为66 000,而正常大鼠尿液中的大鼠白蛋白含量一般为2~20mg/L,采用酶联分析直接测出正常大鼠尿样中的大鼠白蛋白含量对药物代谢实验具有重要意义。 相似文献
6.
大鼠经腹腔一次性注入7.4×10~5Bq·g~(-1)体重氚水后,分别在第1、3、5、7、12、20和35天观察大鼠体重、血象、肝、肾、肺的损伤。结果表明:血象从第1天、肝脏从第3天开始出现损伤,其后逐渐加剧,二者均以第7天最为严重。从第12天开始恢复,到第35天基本恢复正常。在所观察的指标中,以血象及肝脏的病理损伤较为敏感且基本同步,体重的变化不明显。 相似文献
7.
The apatite-coated chitosan microspheres were fabricated by incubating chitosan in five times simulated body fluid. The apatite deposited on the microspheres was similar to natural bone mineral, as demonstrated by scanning electron microscopy, X-ray diffraction spectra and Fourier transformed-infrared spectroscopy analyses. Rat bone marrow-derived mesenchymal stem cells (BMSCs) were seeded on apatite- coated microspheres to investigate the effect of this scaffold on cell proliferation and differentiation. BMSCs seeded on uncoated microspheres were served as a control. In vivo experiment was evaluated by transplanting the microspheres loaded with or without BMSCs in 5-mm cranial defects of Wistar rats. Bone regeneration was investigated via micro-CT and histological analysis. It was found that apatite-coated chitosan microspheres could significantly promote the proliferation and alkaline phosphatase activity of BMSCs compared with uncoated microspheres. Histological slices and Micro-CT images at 8 weeks revealed much better regeneration of bone in the apatite-coated microspheres loaded with BMSCs than the control. In addition, the defect filled with pure microspheres induced little new bone formation. Our findings suggest that the apatite-coated chitosan microspheres scaffold is a promising carrier of stem cells for cranial bone tissue engineering. 相似文献
8.
Enhanced healing of full-thickness diabetic wounds using bioactive glass and Yunnan baiyao ointments
In order to accelerate the chronic wounds healing, we investigated the healing effects of bioactive glass and Yuunan baiyao ointments in streptozotocin-induced diabetic rats. The ointments were prepared by mixing 45S5 bioactive glass powder (16% weight) with Vaseline and different weight percentages of Yurman baiyao. Full-thickness defect wounds were created on the back of 130 SD rats and were randomly divided into 8 groups. The wound healing rates were calculated at 4, 7, 10, 14 and 21 days after surgery. The samples were harvested for further observations. Considering the wound closure rate, group 6 (with 5% Yuunan baiyao) has better wound healing performance than other diabetic groups. The lower inflammatory response was observed by gross observation and confirmed by the results of H&E staining and TEM observation. Besides, the proliferation of fibroblasts, the formation of granulation tissue, as well as the vascularization, were improved in group 6 compared to other diabetic groups. All results suggest that bioactive glass and Yunnan baiyao ointments can accelerate the recovery of diabetes-impaired skin wounds, and comparing to other diabetic groups, group 6 (with 5% Yunnan baiyao) has better healing effect. 相似文献
9.
10.