全文获取类型
收费全文 | 360篇 |
免费 | 6篇 |
专业分类
电工技术 | 18篇 |
化学工业 | 80篇 |
金属工艺 | 5篇 |
机械仪表 | 4篇 |
建筑科学 | 12篇 |
能源动力 | 7篇 |
轻工业 | 12篇 |
无线电 | 23篇 |
一般工业技术 | 41篇 |
冶金工业 | 141篇 |
原子能技术 | 3篇 |
自动化技术 | 20篇 |
出版年
2023年 | 2篇 |
2022年 | 3篇 |
2021年 | 5篇 |
2020年 | 3篇 |
2019年 | 4篇 |
2017年 | 2篇 |
2016年 | 7篇 |
2015年 | 3篇 |
2014年 | 5篇 |
2013年 | 8篇 |
2012年 | 5篇 |
2011年 | 8篇 |
2010年 | 9篇 |
2009年 | 9篇 |
2008年 | 11篇 |
2007年 | 8篇 |
2006年 | 9篇 |
2005年 | 16篇 |
2004年 | 13篇 |
2003年 | 9篇 |
2002年 | 14篇 |
2001年 | 7篇 |
2000年 | 8篇 |
1999年 | 8篇 |
1998年 | 46篇 |
1997年 | 21篇 |
1996年 | 18篇 |
1995年 | 15篇 |
1994年 | 10篇 |
1993年 | 9篇 |
1992年 | 5篇 |
1991年 | 2篇 |
1990年 | 4篇 |
1989年 | 2篇 |
1988年 | 4篇 |
1987年 | 2篇 |
1985年 | 9篇 |
1984年 | 5篇 |
1983年 | 3篇 |
1982年 | 5篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 2篇 |
1978年 | 4篇 |
1977年 | 5篇 |
1976年 | 7篇 |
1970年 | 1篇 |
1968年 | 1篇 |
1966年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有366条查询结果,搜索用时 15 毫秒
141.
Interleukin 6 (IL-6) is a multifunctional inflammatory cytokine whose abnormal production has been implicated in a variety of diseases. Our previous study demonstrated that exudative pleural effusions contain a large amount of IL-6, and the levels of IL-6 in pleural effusion have diagnostic and pathophysiologic values. Although IL-6 is produced by a variety of cells, the origin of IL-6 in pleural effusion has not been determined clearly. We hypothesized that pleural mesothelial cells (PMCs) are an important source of IL-6 in pleural diseases. In this study, we tried to demonstrate whether PMCs could produce IL-6 and to characterize the modulation of its production. PMCs were established from patients with nonmalignant pleural effusion. Immunoreactive IL-6 could be detected in cultured supernatants of all PMCs from five patients, and all IL-6 detected in the supernatants were biologically active. IL-6 production was augmented by the addition of interleukin 1 alpha (IL-1 alpha) in a dose-dependent manner and suppressed by dexamethasone. Expression of IL-6 mRNA was spontaneously observed and was increased by IL-1 alpha. PMCs also expressed mRNA for IL-6 receptors gp80 and gpl30. Spontaneous cell growth and DNA synthesis of PMCs were inhibited by the addition of a neutralizing anti-IL-6 monoclonal antibody and were promoted by the addition of IL-6 to the culture. These results suggest that IL-6 is an autocrine growth factor for PMCs. 相似文献
142.
S Makinoda M Nishiya M Sogame M Mikuni T Kojo T Fujino H Hareyama S Fujimoto 《Canadian Metallurgical Quarterly》1996,81(4):385-389
The effect of acute hypoxia on the changes of plasma cortisol level and hippocampus NE level of cat during inhalation of 21%, 10.4% or 7.9% O2 were investigated. It was found that both 10.4% and 7.9% O2 inhalation caused a gradual increase in plasma cortisol level reaching a plateau in 30-45 min time. While the contents of NE in VHIP and DHIP showed significant decrease 30 min after hypoxia. The degree of both these changes are not related to the hypoxic level of the inhaled O2. The results show that acute hypoxic stress would induce some increase in plasma cortisol level and some decrease in hippocampus NE content. 相似文献
143.
H Ishii S Okada T Sato H Nose T Okusaka M Yoshimori K Takayasu T Takayama T Kosuge S Yamasaki 《Canadian Metallurgical Quarterly》1996,43(9):644-650
BACKGROUND/AIMS: This study was conducted to clarify the effect of percutaneous ethanol injection (PEI) in combination with transcatheter arterial embolization (TAE) on prolonging the survival time of patients with postoperative recurrence of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: The subjects were 97 consecutive patients (pts) treated for postoperative recurrent HCC between February 1987 and March 1993. Of these, 25 pts received both TAE and PEI and 72 pts received TAE alone. In the TAE & PEI group, treatment was selected according to the indications: 15 pts received TAE for multiple recurrences following PEI, and the other 10 pts received PEI for a new or residual lesion following TAE. Fourteen demographic, pathological, and clinical variables were evaluated to estimate the relative risk of pts treated with TAE & PEI or with TAE alone. RESULTS: The 1-, 3- and 5- year survival rates in the TAE & PEI group were 100%, 73.2% and 27.2%, respectively, and those in the TAE alone group were 88.9%, 30.2% and 5.5%, respectively. Based on multi-variate Cox regression analysis, the relative risk of cancer death in the TAE & PEI group was 0.32 (95% confidence interval, 0.15 to 0.67). CONCLUSION: The combination of TAE and PEI had a positive palliative effect and increased survival time of patients with postoperative recurrent HCC, compared to results obtained by TAE alone. 相似文献
144.
M Ohtsuji JS Lai SR Binder T Kondo T Takayasu T Ohshima 《Canadian Metallurgical Quarterly》1996,41(5):881-886
The REMEDi HS is a broad spectrum drug identification system, designed for emergency toxicology screening and forensic applications. The total analysis time is about 20 min. The current library has 555 drugs and metabolites. The system has a software routine that uses an internal standard (IS) to perform quantitative analysis for target compounds when calibrators are available; further, response factors (RF) are supplied for a rapid estimate of drug concentrations when calibrators are unavailable. In the present study, The concentrations of six drugs (bromisovalum, ephedrine, hydroxyzine, diphenhydramine, ranitidine, and lidocaine) and a metabolite of lidocaine (glycinexylidide) were determined using both methods. The slopes of the regression lines between the rapid estimate method and the IS method were generally within 20% of unity, in agreement with the manufacturer's claim. Semiquantitative estimates based on RF also showed good agreement with results obtained using multipoint calibration. These estimates were sufficient for clinical differentiation of routine and toxic levels. Our study demonstrated that the REMEDi HS is particularly useful for a rapid estimate of drug concentrations in the samples from emergency cases when calibrators are not readily available. Our study also showed that this system can be used for the therapeutic monitoring of ranitidine, bromisovalum, lidocaine, and diphenhydrmine. 相似文献
145.
E Fujino T Fujino S Karita K Sakka K Ohmiya 《Canadian Metallurgical Quarterly》1995,177(17):5169-5175
The 6.2-kbp DNA fragment encoding the enzymes in the porphyrin synthesis pathway of a cellulolytic anaerobe, Clostridium josui, was cloned into Escherichia coli and sequenced. This fragment contained four hem genes, hemA, hemC, hemD, and hemB, in order, which were homologous to the corresponding genes from E. coli and Bacillus subtilis. A typical promoter sequence was found only upstream of hemA, suggesting that these four genes were under the control of this promoter as an operon. The hemA and hemD genes cloned from C. josui were able to complement the hemA and hemD mutations, respectively, of E. coli. The COOH-terminal region of C. josui HemA and the NH2-terminal region of C. josui HemD were homologous to E. coli CysG (Met-1 to Leu-151) and to E. coli CysG (Asp-213 to Phe-454) and Pseudomonas denitrificans CobA, respectively. Furthermore, the cloned 6.2-kbp DNA fragment complemented E. coli cysG mutants. These results suggested that both C. josui hemA and hemD encode bifunctional enzymes. 相似文献
146.
A Asakawa A Inui K Momose N Ueno MA Fujino M Kasuga 《Canadian Metallurgical Quarterly》1998,9(10):2265-2267
This study was designed to investigate the effects of endomorphin 1 and 2, recently identified mu-opioid receptor selective peptides, on food intake and anxiety in non-food-deprived mice. The intracerebroventricular (i.c.v.) injection of either endomorphin 1 or 2 (0.03-30 nmol) increased food intake in a dose-related manner. A significant increase was observed 20 min after i.c.v. injection of endomorphin 1 or 2 and continued for 4 h. In the elevated plus maze test, the i.c.v. injection of endomorphin 1 (30 nmol) significantly decreased the normal preference for the closed arms. These results suggest that endomorphin produces orexigenic and anxiolytic effects, and that the mu-opioid receptor contributes to the regulation of feeding and anxiety in mice. 相似文献
147.
In the yeast Saccharomyces cerevisiae, Sic1, an inhibitor of Clb-Cdc28 kinases, must be phosphorylated and degraded in G1 for cells to initiate DNA replication, and Cln-Cdc28 kinase appears to be primarily responsible for phosphorylation of Sic1. The Pho85 kinase is a yeast cyclin-dependent kinase (Cdk), which is not essential for cell growth unless both CLN1 and CLN2 are absent. We demonstrate that Pho85, when complexed with Pcl1, a G1 cyclin homologue, can phosphorylate Sic1 in vitro, and that Sic1 appears to be more stable in pho85Delta cells. Three consensus Cdk phosphorylation sites present in Sic1 are phosphorylated in vivo, and two of them are required for prompt degradation of the inhibitor. Pho85 and other G1 Cdks appear to phosphorylate Sic1 at different sites in vivo. Thus at least two distinct Cdks can participate in phosphorylation of Sic1 and may therefore regulate progression through G1. 相似文献
148.
O. Yong-Taeg Shigeru Fujino Kenji Morinaga 《Science and Technology of Advanced Materials》2002,3(4):1898
Transparent silica glasses were obtained by sintering a green compact (fabricated by slip-casting methods for high-purity silica glass powder) in diverse atmospheres. The relationships between sintering atmosphere and sintering temperature that result in transparent, sintered silica glass were shown. The results indicate that there are four forming phases for each sintering atmosphere and temperature: (1) nontransparent glass resulting from an overabundance of pores (2) crystal, such as cristobalite or β-quartz, (3) moganite, and (4) transparent glass. Optimum sintering temperature for fabricating transparent silica glass was above 1673 K in a high-vacuum (10−4 Pa: p(O2)=10−14) atmosphere. We investigate the fabrication of transparent and hydroxyl-free silica glass by a powder-sintered method. After studying the effect of sintering schedule on residual [OH−] concentration for transparent, sintered silica glasses, we sintered a green compact prepared by silica powders with a mean particle size of 1.6 μm, first heating it to 1523 K for dehydration and then to 1873 K for densification. This typical fabricated condition resulted in a transparent, sintered silica glass with <1 ppm [OH−] concentration. 相似文献
149.
150.