全文获取类型
收费全文 | 276篇 |
免费 | 8篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 13篇 |
综合类 | 1篇 |
化学工业 | 66篇 |
金属工艺 | 7篇 |
机械仪表 | 2篇 |
建筑科学 | 7篇 |
能源动力 | 13篇 |
轻工业 | 60篇 |
水利工程 | 1篇 |
石油天然气 | 1篇 |
无线电 | 16篇 |
一般工业技术 | 25篇 |
冶金工业 | 49篇 |
原子能技术 | 9篇 |
自动化技术 | 16篇 |
出版年
2023年 | 2篇 |
2022年 | 1篇 |
2021年 | 11篇 |
2020年 | 4篇 |
2019年 | 6篇 |
2018年 | 6篇 |
2017年 | 3篇 |
2016年 | 5篇 |
2015年 | 3篇 |
2014年 | 6篇 |
2013年 | 18篇 |
2012年 | 11篇 |
2011年 | 20篇 |
2010年 | 9篇 |
2009年 | 11篇 |
2008年 | 18篇 |
2007年 | 19篇 |
2006年 | 16篇 |
2005年 | 12篇 |
2004年 | 9篇 |
2003年 | 6篇 |
2002年 | 5篇 |
2001年 | 7篇 |
1999年 | 6篇 |
1998年 | 23篇 |
1997年 | 6篇 |
1996年 | 7篇 |
1995年 | 3篇 |
1994年 | 4篇 |
1993年 | 1篇 |
1992年 | 5篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 4篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1976年 | 3篇 |
1975年 | 2篇 |
1971年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有286条查询结果,搜索用时 656 毫秒
161.
Tatsuo Uchida Ryosuke Ohtera Kazuhiro Wako Yumiko Ishitaka Mitsuru Kano K. Klntr 《Journal of the Society for Information Display》2019,27(11):700-707
We devised and developed functional projection screen for personal use, small meetings, car pillars, and near‐eye projection. The screen deflects incident light from a projector by a fixed angle θview and diffuses in a certain angular range Δθview. We have realized the screen by modifying the fine structures based on the corner cube reflector (CCR) and reported basic concept and optical characteristics at IDW2017 and SID2018. However, there remained issues of light in unnecessary direction and insufficient uniformity of the diffused light. In this paper, we report on further modification of the fine structures by optimizing the inclination angles of three curved surfaces of the CCR that result in change of the diffused light pattern. Consequently, the modifications of the deflection angle θview and the diffusion angle Δθview resulted in significant improvement in the screen characteristics. These new results were applied to the screen for personal use and car pillar applications. 相似文献
162.
Takahiro Kaido Masahiro Yoda Tomu Kamijo Shinpei Arai Chiaki Taira Yumiko Higuchi Nobuo Okumura 《International journal of molecular sciences》2020,21(24)
We identified a novel heterozygous variant, Bβp.Pro234Leu (fibrinogen Tokorozawa), which was suspected to be associated with hypofibrinogenemia. Therefore, we analyzed the assembly and secretion of this fibrinogen using Chinese hamster ovary (CHO) cells. To determine the impact on the synthesis and secretion of fibrinogen of the Bβp.P234L and γp.G242E substitutions, we established recombinant variant fibrinogen-producing CHO cell lines. Synthesis and secretion analyses were performed using an enzyme-linked immunosorbent assay (ELISA) and immunoblotting analysis with the established cell lines. In addition, we performed fibrin polymerization using purified plasma fibrinogen and in-silico analysis. Both Bβp.P234L and γp.G242E impaired the secretion and synthesis of fibrinogen. Moreover, immunoblotting analysis elucidated the mobility migration of the Bβγ complex in Bβp.P234L. On the other hand, the fibrin polymerization of fibrinogen Tokorozawa was similar to that of normal fibrinogen. In-silico analysis revealed that the Bβp.P234 residue is located in the contact region between the Bβ and γ chains and contacts γp.G242 residue. The present study demonstrated that the Bβp.P234L substitution resulted in hypofibrinogenemia by decreasing the assembly and secretion of fibrinogen. Therefore, there is a possibility that substitutions in the contact region between the Bβ and γ chains impact the assembly and secretion of fibrinogen. 相似文献
163.
Taiyo Shijo Yoichi Sakurada Koji Tanaka Akiko Miki Seigo Yoneyama Yumiko Machida Aya Chubachi Yu Wakatsuki Atsushi Sugiyama Hajime Onoe Wataru Kikushima Ryusaburo Mori Kenji Kashiwagi 《International journal of molecular sciences》2021,22(8)
Few studies report drusenoid pigment epithelial detachment (DPED) in Asians. In this multicenter study, we report the clinical and genetic characteristics of 76 patients with DPED, and, for comparison, 861 patients with exudative age-related macular degeneration (AMD) were included. On the initial presentation, the mean best-corrected visual acuity was 0.087 ± 0.17 (logMAR unit), and mean DPED height and width were 210 ± 132 and 1633 ± 1114 µm, respectively. Fifty-one (67%) patients showed macular neovascularization in the contralateral eye. The risk allele frequency of both ARMS2 A69S and CFH I62V was significantly higher in DPED than in typical AMD and polypoidal choroidal vasculopathy (PCV) (ARMS2 A69S risk allele frequency: DPED 77% vs. typical AMD 66% vs. PCV 57%, CFH I62V risk allele frequency: DPED 87% vs. typical AMD 73% vs. PCV 73%), although the risk allele frequency of both genes was similar between the DPED group and retinal angiomatous proliferation (RAP) group (ARMS2 A69S: p = 0.32, CFH I62V, p = 0.11). The prevalence of reticular pseudodrusen (RPD) was highest in RAP (60%), followed by DPED (22%), typical AMD (20%), and PCV (2%). Although the prevalence of RPD differs between DPED and RAP, these entities share a similar genetic background in terms of ARMS2 and CFH genes. 相似文献
164.
Yumiko Tahira Katsuya Sakai Hiroki Sato Ryu Imamura Kunio Matsumoto 《International journal of molecular sciences》2021,22(17)
NK1, a splicing variant of hepatocyte growth factor (HGF), binds to and activates Met receptor by forming an NK1 dimer and 2:2 complex with Met. Although the structural mechanism underlying Met activation by HGF remains incompletely resolved, it has been proposed that the NK1 dimer structure participates in this activation. We investigated the NK1 dimer interface’s role in Met activation by HGF. Because N127, V140, and K144 are closely involved in the head-to-tail NK1 dimer formation, mutant NK1 proteins with replacement of these residues by alanine were prepared. In Met tyrosine phosphorylation assays, N127-NK1, V140-NK1, and K144-NK1 showed 8.3%, 23.8%, and 52.2% activity, respectively, compared with wild-type NK1. Although wild-type NK1 promoted cell migration and scattering, N127-NK1, V140-NK1, and K144-NK1 hardly or marginally promoted them, indicating loss of activity of these mutant NK1 proteins to activate Met. In contrast, mutant HGFs (N127-HGF, V140-HGF, and K144-HGF) with the same amino acid replacements as in NK1 induced Met tyrosine phosphorylation and biological responses at levels comparable to those of wild-type HGF. These results indicate that the structural basis responsible for NK1-dependent Met dimer formation and activation differs from, or is at least distinguishable from, the structural basis responsible for HGF-dependent Met activation. 相似文献
165.
Stable isotope data have been increasingly used to assess in situ biodegradation of organic contaminants in groundwater. The data are usually evaluated using the Rayleigh equation to evaluate whether isotope data follow a Rayleigh trend, to calculate the extent of contaminant biodegradation, or to estimate first-order rate constants. However, the Rayleigh equation was developed for homogeneous systems while in the subsurface, contaminants can migrate at different velocities due to physical heterogeneity. This paper presents a method to quantify the systematic effect that is introduced by applying the Rayleigh equation to field isotope data. For this purpose, the travel time distribution between source and sampling point is characterized by an analytical solution to the advection-dispersion equation. The systematic effect was evaluated as a function of the magnitude of physical heterogeneity, geometry of the contaminant plume, and degree of biodegradation. Results revealed that the systematic effect always leads to an underestimation of the actual values of isotope enrichment factors, the extent of biodegradation, or first-order rate constants, especially in the dispersion-dominant region representing a higher degree of physical heterogeneity. A substantial systematic effect occurs especially for the quantification of first-order rate constants (up to 50% underestimation of actual rate) while it is relatively small for quantification of the extent of biodegradation (< 5% underestimation of actual degree of biodegradation). The magnitude of the systematic effect is in the same range as the uncertainty due to uncertainty of the analytical data, of the isotope enrichment factor, and the average travel time. 相似文献
166.
Yumiko Yoshie-Stark Mariko Tsukamoto Kazuyuki Futagawa Mitsutoshi Kubota Mariko Ogushi 《Food chemistry》2009
Surimi is stabilized minced fish meat that is washed with water and blended with cryoprotectants. In this study, surimi from southern blue whiting (Micromesistius australis), surimi not subjected to washing entailing several changes of cryoprotectants following Patent WO/2003/013280 (hereafter termed unwashed surimi), heated surimi samples, and their hydrolysates were prepared to compare their compositions and bioactivities. Methanolic extracts of surimi and their hydrolysates were prepared for further analysis. The heated surimi samples showed different characteristics from the raw materials and released amino acids with enzymatic treatment. Unwashed surimi showed a significantly stronger 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity than surimi, and its effect on radical scavenging was compatible with that of southern blue whiting muscle. There was no significant difference in angiotensin converting enzyme inhibitory activity between unwashed and washed surimi. Soybean lipoxygenase was inhibited by heated unwashed surimi, indicating that unwashed surimi can be used for soymilk and its products. 相似文献
167.
Chemical composition,functional properties,and bioactivities of rapeseed protein isolates 总被引:1,自引:0,他引:1
In order to utilize rapeseed protein from oil industry waste for food applications, rapeseeds were pretreated to remove the oil using hexane. Two protein isolates were prepared, one by precipitation at controlled pH and the other by ultrafiltration. The precipitated and ultrafiltered protein isolates, respectively, contained 70.8% and 98.7% protein. The ultrafiltered protein isolate had a better emulsification capacity than had whole egg. The ultrafiltered protein isolate had a protein solubility of 52.5–97.2% in the range pH 3–9, whilst the maximum protein solubility of the precipitated protein isolate was 26.4% in the pH range 7–9. There were no significant differences between the precipitated and ultrafiltered protein isolates regarding their angiotensin converting enzyme inhibition are their bile acid-binding capacity. Their bile acid-binding capacity and angiotensin converting enzyme inhibition capacities were lower than of those de-oiled soybean. They showed stronger DPPH radical-scavenging activity than did de-oiled soybean. 相似文献
168.
TJS lasers with a planar structure were fabricted by growing GaAs-AlGaAs double heterstructures in reverse-mesa-etched shapes in semi-insulting GaAs substrates. Continuous single-mode operation was achieved at temperatures up to 110°C. The minimum threshold current was 25 mA at 25°C. 相似文献
169.
170.
L-alpha-amino acids with a nucleobase in the side chain (nucleobase amino acids; NBAs) were used to enhance the function of RNA-binding proteins that recognize structured RNA. These NBAs were utilized in the three-dimensional structure of the protein to enhance RNA binding affinity and specificity as a result of selective recognition of NBAs by RNA bases. NBA units were incorporated at various positions into the HIV-1 nucleocapsid protein NCp7 (residues 1-55), which contains two CCHC-type (Cys-X(2)-Cys-X(4)-His-X(4)-Cys-type; X=an amino acid residue) zinc knuckle domains. The binding ability was evaluated by using the stem-loop (SL)3 region of HIV-1 Psi-RNA. Visible light absorption measurements revealed that two zinc ions bound strongly and quantitatively to the NBA-NCp7 molecule and to the wild-type NCp7 protein. This result indicates that the incorporation of NBA units composed of L-alpha-amino acids did not influence the formation of the specific structure of NCp7. Binding analysis with fluorescein-labeled SL3 RNA revealed that incorporation of NBA units into the NCp7 protein at appropriate positions increased its RNA binding affinity and specificity. An NBA-NCp7 protein that possessed cytosine and guanine NBA units at positions 13 and 46, respectively, showed a binding affinity for SL3 RNA ninefold higher than that of wild-type NCp7 as a result of the specific and cooperative interaction of the NBA units with RNA bases. These results clearly demonstrate that inclusion of NBA units in the three-dimensional structure of an RNA-binding protein is a useful strategy for enhancing the function of the protein. 相似文献