全文获取类型
收费全文 | 935篇 |
免费 | 16篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 95篇 |
综合类 | 5篇 |
化学工业 | 278篇 |
金属工艺 | 20篇 |
机械仪表 | 20篇 |
建筑科学 | 43篇 |
能源动力 | 37篇 |
轻工业 | 92篇 |
水利工程 | 5篇 |
无线电 | 46篇 |
一般工业技术 | 134篇 |
冶金工业 | 76篇 |
原子能技术 | 43篇 |
自动化技术 | 60篇 |
出版年
2022年 | 12篇 |
2021年 | 15篇 |
2020年 | 4篇 |
2019年 | 3篇 |
2018年 | 6篇 |
2017年 | 10篇 |
2016年 | 15篇 |
2015年 | 3篇 |
2014年 | 13篇 |
2013年 | 46篇 |
2012年 | 27篇 |
2011年 | 39篇 |
2010年 | 35篇 |
2009年 | 38篇 |
2008年 | 50篇 |
2007年 | 38篇 |
2006年 | 35篇 |
2005年 | 33篇 |
2004年 | 25篇 |
2003年 | 26篇 |
2002年 | 42篇 |
2001年 | 9篇 |
2000年 | 15篇 |
1999年 | 24篇 |
1998年 | 25篇 |
1997年 | 32篇 |
1996年 | 27篇 |
1995年 | 24篇 |
1994年 | 37篇 |
1993年 | 20篇 |
1992年 | 12篇 |
1991年 | 20篇 |
1990年 | 14篇 |
1989年 | 13篇 |
1988年 | 12篇 |
1987年 | 15篇 |
1986年 | 19篇 |
1985年 | 12篇 |
1984年 | 14篇 |
1983年 | 12篇 |
1982年 | 13篇 |
1981年 | 9篇 |
1980年 | 9篇 |
1979年 | 9篇 |
1978年 | 7篇 |
1977年 | 5篇 |
1976年 | 7篇 |
1975年 | 7篇 |
1973年 | 7篇 |
1972年 | 3篇 |
排序方式: 共有954条查询结果,搜索用时 15 毫秒
951.
Satoshi Kubota Eriko Aoyama Masaharu Takigawa Takashi Nishida 《International journal of molecular sciences》2022,23(15)
Fibroblast growth factors (FGFs) constitute a large family of signaling molecules that act in an autocrine/paracrine, endocrine, or intracrine manner, whereas the cellular communication network factors (CCN) family is composed of six members that manipulate extracellular signaling networks. FGFs and CCNs are structurally and functionally distinct, except for the common characteristics as matricellular proteins. Both play significant roles in the development of a variety of tissues and organs, including the skeletal system. In vertebrates, most of the skeletal parts are formed and grow through a process designated endochondral ossification, in which chondrocytes play the central role. The growth plate cartilage is the place where endochondral ossification occurs, and articular cartilage is left to support the locomotive function of joints. Several FGFs, including FGF-2, one of the founding members of this family, and all of the CCNs represented by CCN2, which is required for proper skeletal development, can be found therein. Research over a decade has revealed direct binding of CCN2 to FGFs and FGF receptors (FGFRs), which occasionally affect the biological outcome via FGF signaling. Moreover, a recent study uncovered an integrated regulation of FGF and CCN genes by FGF signaling. In this review, after a brief introduction of these two families, molecular and genetic interactions between CCN and FGF family members in cartilage, and their biological effects, are summarized. The molecular interplay represents the mutual involvement of the other in their molecular functions, leading to collaboration between CCN2 and FGFs during skeletal development. 相似文献
952.
Mohammad Ibtehaz Alam Megumi Mae Fatima Farhana Masayuki Oohira Yasunori Yamashita Yukio Ozaki Eiko Sakai Atsutoshi Yoshimura 《International journal of molecular sciences》2022,23(11)
In inflammatory bone diseases such as periodontitis, the nucleotide-binding oligomerization domain, leucine-rich repeat, and pyrin domain-containing 3 (NLRP3) inflammasome accelerates bone resorption by promoting proinflammatory cytokine IL-1β production. However, the role of the NLRP3 inflammasome in physiological bone remodeling remains unclear. Here, we investigated its role in osteoclastogenesis in the presence and absence of lipopolysaccharide (LPS), a Gram-negative bacterial component. When bone marrow macrophages (BMMs) were treated with receptor activator of nuclear factor-κB ligand (RANKL) in the presence of NLRP3 inflammasome inhibitors, osteoclast formation was promoted in the absence of LPS but attenuated in its presence. BMMs treated with RANKL and LPS produced IL-1β, and IL-1 receptor antagonist inhibited osteoclastogenesis, indicating IL-1β involvement. BMMs treated with RANKL alone produced no IL-1β but increased reactive oxygen species (ROS) production. A ROS inhibitor suppressed apoptosis-associated speck-like protein containing a caspase-1 recruitment domain (ASC) speck formation and NLRP3 inflammasome inhibitors abrogated cytotoxicity in BMMs treated with RANKL, indicating that RANKL induces pyroptotic cell death in BMMs by activating the NLRP3 inflammasome via ROS. This suggests that the NLRP3 inflammasome promotes osteoclastogenesis via IL-1β production under infectious conditions, but suppresses osteoclastogenesis by inducing pyroptosis in osteoclast precursors under physiological conditions. 相似文献
953.
Yukio Watanabe Ikurou Kawai Akira Kowada Shodo Akita Yoshitetsu Itou Youichi Sono Mitsuo Koyanagi Mikio Yamamoto 《Nuclear Engineering and Design》2000,200(3):337-351
In Japan, the following five plants in operation use prestressed concrete containment vessels (PCCVs): Tsuruga #2 (in operation in 1987), Ohi #3 and #4 (in operation in 1991 and 1993, respectively), and Genkai #3 and #4 (in operation in 1994 and 1997, respectively). These plants have adopted the hemispherical dome type PCCV with two or three buttresses and unbonded prestressing system. For the above five PCCVs, lift-off tests in the in-service inspection have been carried out 1, 3 and 5 years after the beginning of operation. In addition, concrete strain and temperature have been measured periodically. This paper presents the in-service inspection methods and results of the lift-off tests and the measurement of concrete strain. The given results are as follows. Measured strain shows good agreement with calculated creep and shrinkage strain, so tendon tensile force can be predicted by the design method using calculated strain, and it also matches well the results of the lift-off tests. 相似文献
954.
Yoshiaki Kitamura Satoko Sako Azusa Tsutsui Yasunari Monguchi Tomohiro Maegawa Yukio Kitade Hironao Sajiki 《Advanced Synthesis \u0026amp; Catalysis》2010,352(4):718-730
A ligand‐free and heterogeneous palladium on carbon (Pd/C)‐catalyzed hetero‐Suzuki–Miyaura coupling reaction has been developed. The protocol enables the construction of both heterocyclic‐alicyclic and heterocyclic‐heterocyclic biaryl derivatives in good to excellent yields. Furthermore, Pd/C could be reused. The time‐course study clarified that palladium was leached into the reaction media as the reaction proceeded and then completely deposited on the carbon support. 相似文献