全文获取类型
收费全文 | 1003篇 |
免费 | 3篇 |
专业分类
综合类 | 1篇 |
化学工业 | 13篇 |
机械仪表 | 1篇 |
建筑科学 | 5篇 |
矿业工程 | 1篇 |
轻工业 | 5篇 |
无线电 | 4篇 |
一般工业技术 | 17篇 |
冶金工业 | 952篇 |
原子能技术 | 2篇 |
自动化技术 | 5篇 |
出版年
2022年 | 2篇 |
2020年 | 1篇 |
2019年 | 1篇 |
2017年 | 1篇 |
2016年 | 2篇 |
2014年 | 1篇 |
2013年 | 4篇 |
2012年 | 3篇 |
2011年 | 3篇 |
2010年 | 3篇 |
2009年 | 5篇 |
2008年 | 2篇 |
2007年 | 1篇 |
2006年 | 1篇 |
2005年 | 2篇 |
2004年 | 1篇 |
2002年 | 1篇 |
2000年 | 1篇 |
1999年 | 28篇 |
1998年 | 275篇 |
1997年 | 146篇 |
1996年 | 110篇 |
1995年 | 67篇 |
1994年 | 55篇 |
1993年 | 53篇 |
1992年 | 7篇 |
1991年 | 9篇 |
1990年 | 13篇 |
1989年 | 13篇 |
1988年 | 10篇 |
1987年 | 6篇 |
1986年 | 10篇 |
1985年 | 3篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 4篇 |
1981年 | 10篇 |
1980年 | 8篇 |
1979年 | 3篇 |
1978年 | 4篇 |
1977年 | 46篇 |
1976年 | 78篇 |
1975年 | 1篇 |
1973年 | 1篇 |
1972年 | 2篇 |
1969年 | 1篇 |
1966年 | 1篇 |
1965年 | 1篇 |
1962年 | 1篇 |
1955年 | 1篇 |
排序方式: 共有1006条查询结果,搜索用时 15 毫秒
131.
132.
EG Ford 《Canadian Metallurgical Quarterly》1996,11(5):183-191
Nutritional management in pediatric patients is often considered to be complex and difficult. We review the basic rationale and principles of IV nutrition support in pediatric patients. The unique differences between children and adults are outlined. The nutritional support solution is then divided into the distinct sections of energy, protein, volume, electrolytes minerals and vitamins. Each of these parts is considered separately to allow understanding in a sequential fashion. Different routes of intravenous access are also discussed to include placement, maintenance, treatment of infections and management of catheter thrombosis. 相似文献
133.
LF Dans S Tankeh-Torres CM Amante EG Penserga 《Canadian Metallurgical Quarterly》1997,24(9):1814-1819
Recent analysis of bladder tumors has correlated expression of the neurokine midkine (MK) with poor patient survival. To examine a role for MK and the related pleiotrophin (PTN) in tumorigenesis, they were overexpressed in MCF-7 breast carcinoma cells. Expression had no effect on in vitro growth but conferred a growth advantage in vivo. Enhanced tumor growth correlated with increased vascular density and endothelial proliferation, implicating an angiogenic role for MK and PTN. Angiogenic activity of MK and PTN was confirmed in the rabbit corneal assay. Our data therefore identify two novel targets for antiangiogenic drug development. 相似文献
134.
Designed 2 studies to investigate the forbidden fruit effect in 83 3rd and 4th graders. Results indicate (a) no support for a forbidden fruit effect, (b) that procedural aspects other than the prohibition in the forbidden toy paradigm influenced the child's valuation of the entire toy set, and (c) that there is a necessity for an appropriate comparison condition when using the forbidden toy paradigm. These results are extended to the previous research on the sour grapes effect. (4 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
135.
An ideal, hydrated, nondilute pseudobinary salt-protein-water solution model of the RBC intracellular solution has been developed to describe the osmotic behavior of human erythrocytes during freezing and thawing. Because of the hydration of intracellular solutes (mostly cell proteins), our analytical results predict that at least 16.65% of the isotonic cell water content will be retained within RBCs placed in hypertonic solutions. These findings are consistent not only with the experimental measurements of the amount of isotonic cell water retained within RBCs subjected to nonisotonic extracellular solutions (20-32%) but also with the experimental evidence that all of the water within RBCs is solvent water. By modeling the RBC intracellular solution as a hydrated salt-protein-water solution, no anomalous osmotic behavior is apparent. 相似文献
136.
137.
Cardioacceleration produced by operant conditioning was associated with elevation of plasma renin activity. This study suggests that emotional stimuli, which produce cardioacceleration, may also cause increased renin secretion, thus providing a mechanism by which factors operating through the mind and sodium intake could summate in the production of hypertension. 相似文献
138.
The tensile yield stress is compared with the uniaxial compression yield stress for specimens of polycarbonate tested at constant
strain rate from −120 to + 120°C. The strain rate dependence of the tensile yield stress is also studied from − 140 to + 20°C.
The yield behaviour is described by a modification of the Eyring theory of non-Newtonian viscosity where the deformation is
supposed to involve two different flow processes.
The validity of a yield criterion previously established by one of us, is checked throughout the range of temperatures explored;
the proposed equation gives a good fit to the data provided it is applied separately to each flow process.
Then the present investigation, combining the yield condition with the modified Eyring theory, provides a formalism which
agrees with the data and accurately renders the temperature, strain rate and pressure dependence of the yield stress of polycarbonate. 相似文献
139.
Tryptic digests of four polypeptides found in Kunjin virus-infected Vero cells, NV5, NV4, V3, and NV3, were compared by peptide mapping. The polypeptides to be analyzed were labeled with radioactive methionine and separated by electrophoresis through polyacrylamide gels containing sodium dodecyl sulfate. Because infection of Vero cells by Kunjin virus does not inhibit host cell protein synthesis, radioactively labeled viral polypeptides prepared from infected cells migrate coincidentally during sodium dodecyl sulfate-gel electrophoresis with some of the labeled host proteins. Thus, the genuine viral methionine-containing peptides in tryptic digests of viral proteins have been identified by co-analyzing polypeptides from [3H]methionine-labeled uninfected cells and [35S]methionine-labeled infected cells and determining the 35S/3H ratio in the peptides resolved in two dimensions on thin-layer chromatography plates. The peptide map of NV3 demonstrated that it is host coded, whereas NV5, NV4, and V3 have unique peptide maps and, therefore, account for approximately one-half of the coding potential of Kunjin virus RNA. 相似文献
140.
Antibodies to Candida after operations on the heart 总被引:1,自引:0,他引:1
In order to determine the frequency of hypoxaemia and to evaluate the role of increased closing capacity in producing hypoxaemia in patients with cirrhosis of the liver, 13 patients with well-established cirrhosis were studied. Arterial blood gases, spirometry, lung volume, and closing capacity measurements were made with the patients in the seated and recumbent positions after exclusion of cardiopulmonary dysfunction. Four of 13 and six of 12 patients exhibited significant hypoxaemia in the seated and recumbent positions respectively. Five of 13 patients showed a closing capacity greater than predicted. This frequency of increased closing capacity was not higher than in a group of smokers of the same age. Unlike Ruff et al. (1971), we did not find a consistent relationship between hypoxaemia and closing capacity. 相似文献