全文获取类型
收费全文 | 3876篇 |
免费 | 1篇 |
专业分类
化学工业 | 16篇 |
机械仪表 | 2篇 |
轻工业 | 9篇 |
石油天然气 | 2篇 |
无线电 | 2篇 |
一般工业技术 | 21篇 |
冶金工业 | 3823篇 |
自动化技术 | 2篇 |
出版年
2023年 | 2篇 |
2018年 | 1篇 |
2016年 | 1篇 |
2014年 | 2篇 |
2013年 | 2篇 |
2012年 | 2篇 |
2011年 | 4篇 |
2010年 | 3篇 |
2009年 | 1篇 |
2008年 | 3篇 |
2007年 | 5篇 |
2006年 | 4篇 |
2005年 | 8篇 |
2004年 | 4篇 |
2003年 | 8篇 |
2002年 | 1篇 |
2000年 | 1篇 |
1999年 | 117篇 |
1998年 | 1254篇 |
1997年 | 729篇 |
1996年 | 474篇 |
1995年 | 241篇 |
1994年 | 168篇 |
1993年 | 220篇 |
1992年 | 19篇 |
1991年 | 45篇 |
1990年 | 42篇 |
1989年 | 41篇 |
1988年 | 47篇 |
1987年 | 30篇 |
1986年 | 35篇 |
1985年 | 31篇 |
1983年 | 6篇 |
1982年 | 11篇 |
1981年 | 13篇 |
1980年 | 29篇 |
1979年 | 3篇 |
1978年 | 6篇 |
1977年 | 76篇 |
1976年 | 179篇 |
1975年 | 3篇 |
1966年 | 1篇 |
1964年 | 1篇 |
1955年 | 4篇 |
排序方式: 共有3877条查询结果,搜索用时 10 毫秒
61.
JR García Fernández MA montalbán ML Martín MC Ortiz MA Martínez A García Marcilla 《Canadian Metallurgical Quarterly》1998,43(5):430-432
Acute nonoliguric renal failure developed in a 13-year-old girl, 1 month after the institution of isoniazid therapy because of a positive tuberculin test at school screening. A renal biopsy demonstrated severe crescentic glomerulonephritis with focal interstitial changes. Discontinuation of isoniazid and a short course of steroids and cyclophosphamide therapy were followed by complete recovery. Whereas isoniazid has been shown to induce a lupus-like syndrome and antihistone antinuclear antibodies, our patient displayed none of the clinical or immunological features that are characteristic of drug-induced lupus. Furthermore, none of the identifiable causes for crescentic glomerulonephritis was evident in this girl. To the best of our knowledge this is the first report suggesting a possible association of crescentic glomerulonephritis to isoniazid treatment. 相似文献
62.
63.
C Tarn ML Bilodeau RL Hullinger OM Andrisani 《Canadian Metallurgical Quarterly》1999,274(4):2327-2336
We report construction and characterization of tetracycline-controlled hepatitis B virus pX-expressing hepatocyte (AML12) cell lines. These cell lines were constructed in AML12 clonal isolates (clones 3 and 4), which express constitutively the tetracycline-controlled transactivator. Since pX is implicated in HCC, this immortalized hepatocyte model system was used to investigate the mechanism of pX in transformation. Clonal isolates of 3pX and 4pX lineages display conditional synthesis of pX mRNA and protein and a 2-fold increase in growth saturation density following tetracycline removal, implicating pX in monolayer overgrowth. Interestingly, only 3pX clones display pX-dependent anchorage independence. Clone 3 lineages express hepatocyte nuclear factor-1alpha and hepatocyte-specific marker genes; clone 4 lineages express hepatocyte nuclear factor-1beta and reduced levels of hepatocyte-specific marker genes, suggesting the importance of the differentiated hepatocyte in pX-mediated oncogenic transformation. Importantly, 3pX and 4pX lineages display differential expression of immediate early genes c-fos and ATF3. The pX-transforming 3pX lineage displays early, pX-dependent induction of ATF3 and prolonged induction of c-fos. The nontransforming 4pX cells display an absence of pX-dependent ATF3 induction and transient induction of c-fos. Our results support the direct link of pX expression to oncogenic transformation in 3pX lineage clones and underscore the advantage of this conditional cellular model system for studying mechanisms of pX-mediated oncogenesis. 相似文献
64.
65.
66.
Initial experiments using whole cells have shown that there were specific and saturable interactions between kunjin (KUN) virus and receptor molecules on the Vero cell surfaces. Solubilisation of Vero cell plasma membranes with octyl-D-glucoside (OG) yielded an extract which also interacted specifically with KUN virus. This was proven using electron microscopy. When the virus-OG-extract complex was exposed onto Vero cell monolayers, no KUN virus was observed to enter into the whole cells. This would imply that there was virus-receptor interaction with the OG-extract leaving no free virus to attach to the whole cells. The attachment kinetics of KUN virus was studied further using the Scatchard analysis which indicated the involvement of more than one interactive macromolecule in the attachment event. 相似文献
67.
68.
M Brandt K Boeke ML Phillips G Steinhoff A Haverich 《Canadian Metallurgical Quarterly》1997,16(3):352-359
PURPOSE: We developed two models that are modifications of our original poly(2-hydroxyethyl methacrylate) (PHEMA) core-and-skirt keratoprosthesis. In these keratoprostheses, the mechanical strength of the skirt has been considerably increased with divinyl glycol (DVG) as a cross-linking agent during polymerization. In one (KPro I), methyl methacrylate (MMA) was added as comonomer to increase cell adhesion, and in the other (KPro II), HEMA was polymerized with DVG without comonomer. The aim of this study was to evaluate the process of healing and biocolonization and to ascertain whether KPro I demonstrates better ingrowth than the mechanically stronger KPro II, after implantation in rabbit eyes. METHODS: Ten rabbits were used for each model and studied at five predetermined end points up to 26 weeks. The device was implanted as a full-thickness keratoprosthesis covered with a conjunctival flap. RESULTS: Neither prosthesis demonstrated extrusion or retroprosthetic membrane formation. There was no significant difference between the two types of prosthesis with respect to tissue ingrowth and surrounding tissue melting. Histologically, inflammation was not severe, but calcification was seen in most specimens. Evidence of biodegradation of the prosthesis also was seen. CONCLUSION: In our original keratoprosthesis, fibrovascular invasion had occurred into the prosthetic skirt, but wound dehiscence and low mechanical strength resulted in an unfavorable outcome. In this series, the mechanical properties were improved, and KPro II was stronger than KPro I. Therefore KPro II would be the preferred polymer combination for surgical manipulation. However, biodegradation and calcification require further investigation into the degree and significance of these adverse reactions. 相似文献
69.
70.