全文获取类型
收费全文 | 1728篇 |
免费 | 9篇 |
国内免费 | 4篇 |
专业分类
电工技术 | 13篇 |
综合类 | 1篇 |
化学工业 | 109篇 |
金属工艺 | 19篇 |
机械仪表 | 8篇 |
建筑科学 | 8篇 |
能源动力 | 20篇 |
轻工业 | 28篇 |
水利工程 | 7篇 |
无线电 | 57篇 |
一般工业技术 | 125篇 |
冶金工业 | 1315篇 |
原子能技术 | 8篇 |
自动化技术 | 23篇 |
出版年
2023年 | 2篇 |
2022年 | 5篇 |
2021年 | 15篇 |
2020年 | 3篇 |
2019年 | 11篇 |
2018年 | 4篇 |
2017年 | 5篇 |
2016年 | 6篇 |
2015年 | 6篇 |
2014年 | 10篇 |
2013年 | 15篇 |
2012年 | 12篇 |
2011年 | 34篇 |
2010年 | 12篇 |
2009年 | 16篇 |
2008年 | 21篇 |
2007年 | 16篇 |
2006年 | 13篇 |
2005年 | 18篇 |
2004年 | 11篇 |
2003年 | 24篇 |
2002年 | 13篇 |
2001年 | 10篇 |
2000年 | 10篇 |
1999年 | 47篇 |
1998年 | 433篇 |
1997年 | 232篇 |
1996年 | 147篇 |
1995年 | 94篇 |
1994年 | 76篇 |
1993年 | 92篇 |
1992年 | 20篇 |
1991年 | 27篇 |
1990年 | 21篇 |
1989年 | 34篇 |
1988年 | 18篇 |
1987年 | 21篇 |
1986年 | 18篇 |
1985年 | 16篇 |
1984年 | 4篇 |
1983年 | 6篇 |
1982年 | 10篇 |
1981年 | 8篇 |
1980年 | 17篇 |
1977年 | 39篇 |
1976年 | 62篇 |
1975年 | 2篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1972年 | 1篇 |
排序方式: 共有1741条查询结果,搜索用时 31 毫秒
1.
Takashi Ohnishi Yuki Ogawa Kota Suda Miki Komatsu Satoko Matsumoto Harmon Mitsuru Asukai Masahiko Takahata Norimasa Iwasaki Akio Minami 《International journal of molecular sciences》2021,22(9)
Pyogenic spondylodiscitis can cause severe osteolytic and destructive lesions in the spine. Elderly or immunocompromised individuals are particularly susceptible to infectious diseases; specifically, infections in the spine can impair the ability of the spine to support the trunk, causing patients to be bedridden, which can also severely affect the physical condition of patients. Although treatments for osteoporosis have been well studied, treatments for bone loss secondary to infection remain to be elucidated because they have pathological manifestations that are similar to but distinct from those of osteoporosis. Recently, we encountered a patient with severely osteolytic pyogenic spondylodiscitis who was treated with romosozumab and exhibited enhanced bone formation. Romosozumab stimulated canonical Wnt/β-catenin signaling, causing robust bone formation and the inhibition of bone resorption, which exceeded the bone loss secondary to infection. Bone loss due to infections involves the suppression of osteoblastogenesis by osteoblast apoptosis, which is induced by the nuclear factor-κB and mitogen-activated protein kinase pathways, and osteoclastogenesis with the receptor activator of the nuclear factor-κB ligand-receptor combination and subsequent activation of the nuclear factor of activated T cells cytoplasmic 1 and c-Fos. In this study, we review and discuss the molecular mechanisms of bone loss secondary to infection and analyze the efficacy of the medications for osteoporosis, focusing on romosozumab, teriparatide, denosumab, and bisphosphonates, in treating this pathological condition. 相似文献
2.
3.
4.
T. Takeuchi T. Sasaki M. Hayashi K. Hamamoto K. Makita K. Taguchi K. Komatsu 《Photonics Technology Letters, IEEE》1996,8(3):361-363
A transceiver PIC consisting of a DFB-LD, a receiver PD and a Y-shaped branch waveguides is realized by in-plane bandgap energy controlled selective MOVPE. Both active and passive core layers are formed in one step selective growth, and complicated fabrication procedure is no longer required. More than 1 mW fiber coupled power and 7 GHz receiver bandwidth are obtained. The modulation and detection operations at 500 Mb/s are successfully demonstrated. 相似文献
5.
DD Coelho 《Canadian Metallurgical Quarterly》1997,73(5):397-398
Thoracic infection by anaerobes are uncommon diseases and often presents difficulty in diagnosis. We report a case of thoracic infection due to Fusobacterium Nucleatum. A 60-year old man presented a lesion infiltrating from the lung to the thoracic wall. Fusobacterium Nucleatum was isolated on pus collected. Treatment by penicillin, metronidazole combined with surgical drainage was highly effective. 相似文献
6.
7.
Hiroshi Ito Takehiko Ishiguro Tokutaro Komatsu Nozomu Matsukawa Gunzi Saito Hiroyuki Anzai 《Journal of Superconductivity and Novel Magnetism》1994,7(3):667-669
The superconducting transition of the organic compoundsκ-(BEDT-TTF)2 X is studied by resistive measurement in a magnetic field up to 10 T applied normal to the conducting plane. For the salts withX=Cu[N(CN)2]Br andX=CuCN[N(CN)2] the transition shows fanshaped broadening caused by superconductivity fluctuation. For theX=Cu(NCS)2 salt the resistivity shows a peak in the transition region in a magnetic field below 4 T.This phenomenon is suppressed in defect-reduced samples for intralayer conduction. We discuss this peak in relation to the thermal fluctuation on the Josephson junction structures in this salt. 相似文献
8.
9.
M. Komatsu Y. Matsukawa K. Yasunaga M. Kiritani 《Materials Science and Engineering: A》2003,350(1-2):25-29
Heavy plastic deformation of fcc metal thin foils to fracture has been found recently to proceed without involving dislocations, and it results in the formation of high density of vacancy clusters. Thin foil specimens of bcc metals such as V and Mo were plastically deformed to fracture in in situ elongation experiments under an electron microscope. Morphology of thinning and fracture was found to be similar to fcc metals, and no dislocation was observed during heavy deformation. Electron diffraction analysis at the tip of a crack during deformation confirmed a large elastic deformation of up to 5%. Unlike in fcc metal thin foil specimens, point defect clusters were not observed near fractured tips. This difference is attributed to the difference in vacancy reaction, though the deformation in bcc metals without dislocation most likely does produce vacancies. 相似文献
10.