全文获取类型
收费全文 | 883篇 |
免费 | 1篇 |
专业分类
电工技术 | 2篇 |
化学工业 | 3篇 |
机械仪表 | 2篇 |
轻工业 | 5篇 |
石油天然气 | 1篇 |
无线电 | 1篇 |
一般工业技术 | 7篇 |
冶金工业 | 861篇 |
自动化技术 | 2篇 |
出版年
2022年 | 1篇 |
2021年 | 2篇 |
2017年 | 1篇 |
2016年 | 1篇 |
2015年 | 1篇 |
2014年 | 2篇 |
2013年 | 5篇 |
2011年 | 1篇 |
2010年 | 1篇 |
2009年 | 1篇 |
2008年 | 1篇 |
1999年 | 10篇 |
1998年 | 174篇 |
1997年 | 118篇 |
1996年 | 94篇 |
1995年 | 54篇 |
1994年 | 58篇 |
1993年 | 49篇 |
1992年 | 13篇 |
1991年 | 4篇 |
1990年 | 8篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1983年 | 3篇 |
1982年 | 6篇 |
1981年 | 16篇 |
1980年 | 19篇 |
1978年 | 4篇 |
1977年 | 97篇 |
1976年 | 127篇 |
1975年 | 3篇 |
1954年 | 1篇 |
1899年 | 1篇 |
排序方式: 共有884条查询结果,搜索用时 15 毫秒
91.
92.
93.
VI Pushkareva EN Emel'ianenko LV Didenko ND Konstantinova LV Ponomareva VIu Litvin AL Gintsburg 《Canadian Metallurgical Quarterly》1998,(5):9-13
The dynamics of the transition of Y.pseudotuberculosis to the latent (noncultivable) state in sterile soil extraction and in soil extraction, containing Scenedesmus algae or their exometabolites, was evaluated by the bacteriological method and with the use of polymerase chain reaction. The formation of Y.pseudotuberculosis latent forms achieved its highest rate under the action of algal exometabolites (on day 11), while in the presence of algal cells such formation was delayed to 3-5 months. The partial reversion of Y.pseudotuberculosis nonculativable forms to vegetative, bacteriologically detectable forms occurred under the action of fetal serum, as well as live or killed infusoria. Transmission electron microscopy demonstrated that noncultivable Y.pseudotuberculosis had a round form, diminished cell size, denser cytoplasm and enlarged cytoplasmic space. The reversible transition of bacteria to the latent state is regarded as their adaptation to unfavorable factors during their existence in soils and water reservoirs. 相似文献
94.
95.
Destructive changes in cardiomyocyte mitochondria of patients with diagnosis of alcoholic heart lesion were observed by the ultrastructural analysis of the endocardial biopsies serial sections. The appearance of mitochondria with the third additional compartment and mitochondria having two zones of different electron density not separated into the special compartments are described for the first time. The development of megamitochondria having different morphology is demonstrated. Mitochondrial origin of lipophuscin granules is suggested on the basis of the ultrastructural changes. Unusual structure of atypical mitochondria may provide new properties of these organelles this being considered by the authors as an adaptive cell and mitochondria response to the new metabolic conditions. 相似文献
96.
97.
SE Mano?lov NV Sedykh VI Firsova OR Vennikas LD Cheliadina 《Canadian Metallurgical Quarterly》1996,121(6):638-640
Blepharoptosis is a recognized complication of cataract extraction and other ocular procedures. A 6-month waiting period is recommended before repairing postcataract ptosis because most cases resolve during this time. We report the course of a patient who developed spontaneous recovery of eyelid function 11 months after cataract surgery. She had previously undergone successful ptosis repair 8 months after cataract extraction, but developed overcorrection 3 months later as her levator function returned to normal. We recommend at least a 1-year waiting period before repair of postcataract ptosis. If corrective surgery is undertaken earlier than 1 year due to visual obstruction or for aesthetic reasons, we suggest two guidelines. The levator should be plicated rather than resected and patients should be forewarned of the possibility for a revisionary procedure if spontaneous return of levator function occurs. 相似文献
98.
VA Shevchenko VI Abramov VA Kal'chenko IS Fedotov AV Rubanovich 《Canadian Metallurgical Quarterly》1996,36(4):531-545
Populations of Arabidopsis thaliana (L.) Heynh., and Pinus sylvestris L., growing within 30 km of Chernobyl and Bryansk region have been analyzed for the frequency of embryonic lethal mutations on Arabidopsis and frequency of chlorophyll mutations and chromosome aberrations by pine. On pine also have been analyzed rate of mutations at enzyme loci in endosperms of seeds. Dose dependence of the value genetic damage on level of radioactive pollution was observed. 相似文献
99.
PC Bégué EM Grimprel MD Giovannangeli VI Abitbol 《Canadian Metallurgical Quarterly》1998,17(9):804-809
BACKGROUND: The changing epidemiology of pertussis in France has emphasized the need for booster vaccinations in adolescents. Although not previously recommended because of the high reactogenicity of whole cell pertussis in children older than 2 years old, the development of less reactogenic acellular pertussis vaccines means that this recommendation may be reconsidered. OBJECTIVES: Assessment of the reactogenicity and immunogenicity of a diphtheria-tetanus-acellular pertussis-inactivated poliovirus (DTPa-IPV=Group 1) vaccine administered as the fifth dose in preadolescents in comparison with a commercial diphtheria-tetanus-inactivated poliovirus (DT-IPV) (Group 2) vaccine currently recommended for this age group. MATERIALS AND METHODS: An open, randomized study involving 115 healthy subjects ages 10 to 13 years previously vaccinated with 4 doses of diphtheria-tetanus-whole cell pertussis-IPV vaccines. Reactogenicity was assessed for 4 days postvaccination using diary cards. Immunogenicity based on antibody assays in sera taken before and 1 month postvaccination was evaluated for all vaccine antigen components. RESULTS: Both vaccines showed good tolerability, local and general reactogenicity being similar. For local reactions Group 1=88.1% and Group 2=86.8%, and for general reactions Group 1=40.7% and Group 2=47.2%. Headache was the most frequent general symptom with 27.1% for DTPa-IPV and 39.6% for DT-IPV. The incidence of fever was 5.1% with DTPa-IPV and 9.4% for DT-IPV. Good immune responses were obtained against all vaccine components. CONCLUSIONS: The inclusion of acellular pertussis did not significantly increase the reactogenicity of DTPa-IPV in comparison with the currently recommended DT-IPV vaccine when given as a fifth dose in preadolescents. To prevent recent resurgence of pertussis in France, this vaccine should be preferred as the booster dose of DTPa-IPV at 11 to 13 years of age as recently approved by the National Council of Hygiene of France. 相似文献
100.