全文获取类型
收费全文 | 529篇 |
免费 | 6篇 |
专业分类
电工技术 | 9篇 |
化学工业 | 15篇 |
机械仪表 | 6篇 |
能源动力 | 4篇 |
轻工业 | 31篇 |
无线电 | 29篇 |
一般工业技术 | 23篇 |
冶金工业 | 416篇 |
自动化技术 | 2篇 |
出版年
2024年 | 1篇 |
2023年 | 2篇 |
2020年 | 3篇 |
2018年 | 1篇 |
2017年 | 1篇 |
2016年 | 1篇 |
2015年 | 4篇 |
2014年 | 1篇 |
2013年 | 3篇 |
2012年 | 11篇 |
2011年 | 12篇 |
2010年 | 5篇 |
2009年 | 1篇 |
2008年 | 12篇 |
2007年 | 9篇 |
2006年 | 4篇 |
2005年 | 8篇 |
2004年 | 5篇 |
2003年 | 3篇 |
2002年 | 6篇 |
2001年 | 5篇 |
1999年 | 9篇 |
1998年 | 124篇 |
1997年 | 71篇 |
1996年 | 48篇 |
1995年 | 34篇 |
1994年 | 23篇 |
1993年 | 28篇 |
1992年 | 3篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 3篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1986年 | 5篇 |
1985年 | 5篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 6篇 |
1981年 | 4篇 |
1980年 | 5篇 |
1978年 | 1篇 |
1977年 | 21篇 |
1976年 | 32篇 |
1974年 | 2篇 |
排序方式: 共有535条查询结果,搜索用时 15 毫秒
1.
IG Sumner A Vaughan R Eisenthal RW Pickersgill AJ Owen PW Goodenough 《Canadian Metallurgical Quarterly》1993,1164(3):243-251
Papaya proteinase omega (pp omega) has been purified from dried latex both by immunoaffinity and traditional methods. Kinetic analysis revealed that (1), the pp omega-catalysed hydrolysis of N-benzoyl-L-arginine p-nitroanilide (BApNA) has a lower specificity (kcat/Km) than the same reaction catalysed by papain; (2), the pp omega-catalysed hydrolysis of a tripeptide substrate having phenylalanine at the second position (S2-site) showed a more similar specificity to that catalysed by papain; (3), the significant difference between the two enzymes is that steady state kinetics with both L-BApNA and a tripeptide enables the identification in pp omega of other ionizations affecting binding. The active sites of papain and pp omega can therefore be distinguished by pH-dependence of kcat/Km. 相似文献
2.
DI Timokhin AV Istomin TS Shushkova TG Voronel' IG Mikha?lov 《Canadian Metallurgical Quarterly》1997,(2):19-21
Based on generalization and analysis of instructions and guidelines for therapeutical and prophylactic diets of workers, ways of its optimization were proposed, by using bifide-containing acid dairy products as a preventive agent against possible occupational diseases caused by occupational factors. 相似文献
3.
4.
IG Skripal'' 《Canadian Metallurgical Quarterly》1993,55(3):3-6
The paper presents the results of treating patients with chronic nonspecific diseases of the lung by the use of extracorporeal ultraviolet autoblood irradiation (EUVABI). The marked clinical effect recorded after an EUVABI course coincided with the normalization of an erythrocytic membrane morphoform, which suggests that the severity of allergic and inflammatory reactions was liquidated and blood viscosity was improved. EUVABI led to positive changes in the pattern of morphotypes in the crystallogram of plasma, except the patients who showed no clinical effect, which indicates that plasma crystallography can be used as a diagnostic test in predicting the results of EUVABI application. 相似文献
5.
DK Song HW Suh SO Huh JS Jung BM Ihn IG Choi YH Kim 《Canadian Metallurgical Quarterly》1998,287(1):144-149
The development of control strategies for loiasis is of crucial importance in endemic areas and depends heavily on the accurate identification of occult-infected individuals. A polymerase chain reaction (PCR) and nested polymerase chain reaction (nested PCR) were developed and based on sequences of the repeat 3 region (15r3) of the gene encoding a Loa loa 15-kD protein. The assays was performed on 20 blood samples from occult-infected subjects and 30 from field-collected amicrofilaremic individuals. The size of the initial PCR product was 396 basepairs (bp). When this initial amplification using primers 15r3(1) and 15r3(2) was carried out for 30 cycles, the PCR products from three of the 20 occult-infected and five of the 30 amicrofilaremic individuals were visualized after electrophoresis by staining the gel with ethidium bromide. Subsequent Southern blotting and hybridization with the specific probe revealed hybridization in 19 of 20 occult-infected and 23 of 30 amicrofilaremic samples but only after two days of exposure of the blot to the x-ray film. When the nested PCR was carried out (product size = 366 bp, primers 15r3(3) and 15r3(4)), 19 of 20 occult-infected and 23 of 30 amicrofilaremic samples that were positive by Southern hybridization of the initial PCR products were strongly positive by staining with ethidium bromide. Qualitative Southern blotting of the nested PCR products using the same probe previously described confirmed the ethidium bromide staining results after a very short exposure time of 4 hr. These results demonstrate that the nested PCR amplification product is specific and that its sensitivity in detecting occult loiasis is 95%. This approach has significant promise for the screening of large human populations for active loiasis without the requirement for blotting and hybridization of the PCR products. 相似文献
6.
Guinea pigs were fed one of three diets containing 10% black currant seed oil (a source of gamma-linolenic (18∶3 n−6) and
stearidonic (18∶4 n−3) acids), walnut oil or lard for 40 days. The fatty acid composition of liver triglycerides, free fatty
acids, cholesteryl esters, phosphatidylinositol, phosphatidylserine, cardiolipin, phosphatidylcholine and phosphatidylethanolamine
were determined.
Dietary n−3 fatty acids found esterified in liver lipids had been desaturated and elongated to longer chain analogues, notably
docosapentaenoic acid (22∶5 n−3) and docosahexaenoic acid (22∶6 n−3). When the diet contained low amounts of n−6 fatty acids,
proportionately more of the n−3 fatty acids were transformed. Significantly more eicosapentaenoic acid (EPA) (20∶5 n−3) was
incorporated into triglycerides, cholesteryl esters, phosphatidylcholine and phosphatidylethanolamine of the black currant
seed oil group compared with the walnut oil group.
Feeding black currant seed oil resulted in significant increases of dihomogamma-linolenic acid (20∶3 n−6) in all liver lipid
classes examined, whereas the levels of arachidonic acid (20∶4 n−6) remained relatively stable. The ratio dihomo-gamma-linolenic
acid/arachidonic acid was significantly (2.5-fold in PI to 17-fold in cholesteryl esters) higher in all lipid classes from
the black currant seed oil fed group. 相似文献
7.
Pinon A Alexandre V Cupferman S Crozier A Vialette M 《International journal of cosmetic science》2007,29(2):111-119
The influence of ethanol on the behaviour of Pseudomonas aeruginosa and Staphylococcus aureus strains was evaluated throughout this study. Strains of different origin were used: collection, clinical and industrial strains were selected. Concentrations of ethanol from 0 to 20% (v/v) were evaluated by automated optical density measurements and by enumeration. When growth conditions were observed, predictive microbiology models were used to assess quantitatively for the ethanol effect. Primary modelling of kinetics was performed to determine growth rate values; secondary modelling was performed on these growth rates as influenced by ethanol, and minimum inhibitory concentrations of ethanol were determined for each strain. Staphylococcus aureus strains were more resistant to ethanol than P. aeruginosa strains, in growth conditions as well as in inactivation conditions. Furthermore, clinical S. aureus strains were more resistant than the collection strain. The method was promising for management of microbiological safety in cosmetics. 相似文献
8.
Stuart Crozier Ph.D. Stephen Dodd Kurt Luescher James Field David M. Doddrell 《Magma (New York, N.Y.)》1995,3(1):49-55
By extending the formalism previously developed for the design of unshielded, biplanar gradient coils, shielded biplanarB
0 coils optimized for homogeneity and either minimum energy or minimum power may be designed. We present results from an integrated
approach to shielded biplanar coil design, the results of which are also applicable to gradient coils, enabling the design
of shielded coils with a concomitant decrease in total inductance of the coil. Length constraints are also included in the
integrated minimization procedure. Results from a preliminary design indicate that high-homogeneity, low-impedance, well-shielded
coils result from this design approach. 相似文献
9.