全文获取类型
收费全文 | 677篇 |
免费 | 0篇 |
专业分类
化学工业 | 3篇 |
矿业工程 | 1篇 |
轻工业 | 10篇 |
冶金工业 | 662篇 |
原子能技术 | 1篇 |
出版年
2022年 | 1篇 |
2021年 | 1篇 |
2016年 | 2篇 |
2011年 | 1篇 |
2008年 | 1篇 |
2007年 | 1篇 |
2004年 | 3篇 |
2002年 | 1篇 |
1999年 | 16篇 |
1998年 | 176篇 |
1997年 | 114篇 |
1996年 | 53篇 |
1995年 | 38篇 |
1994年 | 28篇 |
1993年 | 50篇 |
1992年 | 8篇 |
1991年 | 11篇 |
1990年 | 12篇 |
1989年 | 10篇 |
1988年 | 10篇 |
1987年 | 11篇 |
1986年 | 11篇 |
1985年 | 7篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 5篇 |
1981年 | 2篇 |
1980年 | 6篇 |
1979年 | 1篇 |
1978年 | 6篇 |
1977年 | 26篇 |
1976年 | 55篇 |
1975年 | 3篇 |
1973年 | 1篇 |
1955年 | 3篇 |
排序方式: 共有677条查询结果,搜索用时 0 毫秒
51.
52.
Iodine-131, ruthenium-103, and neptunium-239 are present as contaminants in the eluate of 99Mo-99mTc generators loaded with 99Mo prepared by thermal-neutron irradiation of enriched 98Mo. The elution pattern of each of these contaminants is determined, together with the amounts found in the eluate of all generators tested over a 7-month period. 相似文献
53.
Ulnar nerve entrapment at the elbow has been described in the literature. This paper deals with 19 skeletally mature baseball players with ulnar nerve entrapment who underwent surgery for correction of the problem. The surgery consisted of anterior transfer of the nerve and placement deep to the flexor muscles. Six players quit baseball because of continuing elbow problems, nine returned to playing, and four were lost to follow-up. Ulnar nerve entrapment is thought to represent one syndrome in a spectrum of diseases involving the medial side of the elbow in baseball players. The lesion is amenable to surgery. 相似文献
54.
55.
56.
Women alcoholics had higher scores than women social drinkers (indicating greater external control orientation) on both the Internal-External Locus of Control Scale and a Locus of Drinking Control Scale. 相似文献
57.
F Beersiek H Schneiders A Mehdizadeh G Jacobs FW Eigler 《Canadian Metallurgical Quarterly》1976,101(47):1719-1723
During the last 4 years three so-called spontaneous perforations of the oesophagus were treated, twice by surgical intervention 12 anys after the rupture. Two patients survived. The classical history of retching or vomiting and retrosternal splitting pain is indicative, wht medium, amidotrizoate sodium (Gastrografin), from the oesophagus. Prognosis depends decisively on the time of operation after the rupture. Direct suture of the rupture with plastic coverage of the defect by sewing on of the gastric fundus or by plication of the fundus have proved valuable. 相似文献
58.
59.
Fish embryos represent a class of multicompartmental biological systems that have not been successfully cryopreserved, primarily because of the lack of understanding of how water and cryoprotectants permeate the compartments. We are using the zebrafish embryo as a model to understand these kinetics. Zebrafish embryos have two major compartments, the blastoderm and the yolk, which is surrounded by the multinucleated yolk syncytial layer (YSL). We determined the water and cryoprotectant permeability in these compartments using two methods. First, we measured shrink/swell dynamics in optical volumetric experiments. Zebrafish embryos shrank over time and did not re-expand while immersed in dimethyl sulfoxide (DMSO) or propylene glycol. Second, we measured DMSO uptake with diffusion-weighted nuclear magnetic resonance spectroscopy. DMSO uptake was rapid during the first few minutes, then gradual thereafter. We used one- and two-compartment models to analyze the data and to determine the permeability parameters. We found that the two-compartment model provided a better fit to the data. On the basis of this model and in the presence of DMSO, the yolk and blastoderm had very similar water permeabilities (i.e., 0.01 and 0. 005 micron x min-1atm-1, respectively), but they had different DMSO permeabilities separated by three orders of magnitude (i.e., = 5 x 10(-6) and 1.5 x 10(-3) cm/min, respectively). The low solute permeability of the yolk predicted that the yolk/YSL compartment should be more susceptible to cryodamage. To test this, the yolk, blastoderm, and YSL were examined at the ultrastructural level after vitrification. Only the YSL incurred significant damage after freezing and thawing (p = 0.05). 相似文献
60.
HH Al-Sa'doni IL Megson S Bisland AR Butler FW Flitney 《Canadian Metallurgical Quarterly》1997,121(6):1047-1050
1. A study has been made of the effect of neocuproine, a specific Cu(I) chelator, on vasodilator responses of rat isolated perfused tail artery to two nitrosothiols: S-nitroso-N-acetyl-D,L-penicillamine (SNAP) and S-nitroso-glutathione (GSNO). 2. Bolus injections (10 microl) of SNAP or GSNO (10(-7)-10(-3) M) were delivered into the lumen of perfused vessels pre-contracted with sufficient phenylephrine (1-7 microM) to develop pressures of 100-120 mmHg. Two kinds of experiment were made: SNAP and GSNO were either (a) pre-mixed with neocuproine (10(-4) M) and then injected into arteries; or (b) vessels were continuously perfused with neocuproine (10(-5) M) and then injected with either pure SNAP or GSNO. 3. In each case, neocuproine significantly attenuated vasodilator responses to both nitrosothiols, although the nature of the inhibitory effect differed in the two types of experiment. We conclude that the ability of exogenous nitrosothiols to relax vascular smooth muscle in our ex vivo model is dependent upon a Cu(I) catalyzed process. Evidence is presented which suggests that a similar Cu(I)-dependent mechanism is responsible for the release of NO from endogenous nitrosothiols and that this process may assist in maintaining vasodilator tone in vivo. 相似文献