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71.
To evaluate the activity of benzoylphenyl urea chitin biosynthesis inhibitor chlorfluazuron (IKI-7899) against Parasarcophaga argyrostoma, seven doses were topically applied (once) onto early third (last) instar larvae, puparia, or newly formed pupa: 150, 100, 50, 10, 1.0, 0.5, and 0.25 microgram/insect. After topical treatment of last instar larvae, the highest mortality was caused by both higher doses and the lowest mortality was caused by the lowest dose. The lethal activity of IKI-7899 as pronouncedly decreased as the treatment was lately carried out (at the puparial time). IKI-7899 failed to cause cumulative mortality because no pupal or adult mortalities were observed, irrespective of the time of treatment. Treated larvae suffered the action of IKI-7899 because they had decreased weight gain. Except the lowest dose, the weight gain of larvae inversely correlated with the dose-levels. IKI-7899 prolonged not only the larval duration but also the pupal duration after topical treatment of last instar larvae with doses 50-0.25 micrograms/larva. With no exception, all doses topically applied onto puparia or newly formed pupae enhanced pupae to live longer. Topical application onto last instar larvae resulted in different degrees of reduction of pupation rate, but IKI-7899 could not affect the pupal morphogenesis after larval treatment except by its highest dose which led to 8.33% pupal deformities and 7.69% larval-pupal intermediates. The dose 100 micrograms/larva topically applied onto last instar larvae detained 7.69% of what known as "permanent larvae" which suffered the action of the compound along 16 days and eventually perished without any external feature of puparium formation. A metamorphic effect of IKI-7899 pronouncedly appeared in the adult stage. Three higher doses completely arrested the adult flies. Topical application of the compound onto prepupae did not greatly reduce the pupation rate especially at the doses 50, 10 and 1.0 micrograms/puparium. The dose 50 micrograms/puparium was only the dose halting the pupal moulting program because 7.14% of permanent prepupae remained about 12 days and then died. In respect to adult emergence, the highest dose led to zero rate and the lowest dose allowed to all pupae to emerge without malformation. 相似文献
72.
Nanocrystalline yttrium vanadate doped with europium ions powders were synthesized via sol-gel method based on decomposition of metal-polymer complex. X-ray diffraction analysis showed that samples had pure tetragonal phase without any impurities. Scanning electron microscopy and static light scattering technique were used to study morphology and size of prepared nanoparticles. Average diameter of the nanoparticles was about 40 nm. The changes in structural and luminescence properties were observed as a function of the first and second calcination temperature. The optimal conditions for synthesis of nanoparticles were determined as Т1=500 °С, t1=1 h; Т2=950 °С, t2=1.5 h. The effect of different media surrounding the nanoparticles on their luminescence properties and lifetime was investigated and discussed in terms of effective refractive index. It was found that the observed lifetime of YVO4:Eu3+ 5 at.% nanophosphor was decreased from 0.64 ms in air(nmed=1) to 0.45 ms in chalcogenide glass As39S61(nmed=2.39). 相似文献
73.
IM Lebedenko ZP Mikhina RV Stavitski? VN Vasil'ev AA Kokontsev IE Sergeev 《Canadian Metallurgical Quarterly》1998,(4):5-9
Computed tomography assesses the linear coefficient of X-ray radiation decrease in the tissue and hence determines changes in its density thus allowing one to control the destruction of tumor cells and tissues during treatment. The paper proposes a procedure for determining the sizes and density of a tumor along the chosen linear direction crossing the image of a pathological focus. The whole procedure is performed by the special computer programme "Diaglmag". The equations that characterize the dynamics of using the parameters used before, during, and after treatment are presented. Baseline information on the optic image densities on a computer tomogram is obtained with a graphic scanner. The examples presented in the paper show it feasible to solve a difficult task to determine the effect of treatment. This enables a treatment regimen to be corrected in time or modified. 相似文献
74.
75.
Peroxynitrite increases the degradation of aconitase and other cellular proteins by proteasome 总被引:1,自引:0,他引:1
T Grune IE Blasig N Sitte B Roloff R Haseloff KJ Davies 《Canadian Metallurgical Quarterly》1998,273(18):10857-10862
We report that exposure of aconitase to moderate concentrations of peroxynitrite, 3-morpholinosydnonimine (SIN-1; a superoxide- and nitric oxide-liberating substance), or hydrogen peroxide, inhibits the enzyme and enhances susceptibility to proteolytic digestion by the isolated 20 S proteasome. Exposure to more severe levels of oxidative stress, from these same agents, causes further inhibition of the enzymatic activity of aconitase but actually decreases its proteolytic breakdown by proteasome. It should be noted that the superoxide and nitric oxide liberated by SIN-1 decomposition react to form a steady flux of peroxynitrite. S-Nitroso-N-acetylpenicillamine, a compound that liberates nitric oxide alone, causes only a small loss of aconitase activity (25% or less) and has no effect on the proteolytic susceptibility of the enzyme. Proteasome also seems to be the main protease in cell lysates that can degrade aconitase after it has been oxidatively modified by exposure to peroxynitrite, SIN-1, or hydrogen peroxide. Using cell lysates isolated from K562 cells treated for several days with an antisense oligodeoxynucleotide to the initiation codon region of the C2 subunit of proteasome (a treatment which diminishes proteasome activity by 50-60%), the enhanced degradation of moderately damaged aconitase was essentially abolished. Other model proteins as well as complex mixtures of proteins, such as cell lysates, also exhibit enhanced proteolytic susceptibility after moderate SIN-1 treatment. Therefore we conclude that peroxynitrite reacts readily with proteins and that mild modification by peroxynitrite results in selective recognition and degradation by proteasome. 相似文献
76.
EV Egorova IE Ioshin TI Vlasova OS Slepova AI Tolchinskaia 《Canadian Metallurgical Quarterly》1993,109(4):26-28
The authors demonstrate a high informative value of preoperative lacrimal fluid examinations to predict postoperative uveitis in patients with complicated cataracts. Detection of antituberculin antibodies in titers 1:128 or higher is a factor of risk of development of a postoperative inflammatory reaction. The risk of postoperative uveitis is increased to 100% if antibodies to tuberculin, tissue-specific retinal S antigen, and lenticular proteins are simultaneously detected in the lacrimal fluid. 相似文献
77.
A nested polymerase chain reaction (PCR)-based assay, for detection of bluetongue virus (BTV) ribonucleic acid in cell culture and tissue samples, was developed. Two pairs of oligonucleotide primers (BTV1 and BTV4 and BTV2 and BTV3), selected from non-structural protein 1 (NS1) gene of BTV-17, were used for the nested PCR in two amplification steps. First a 826-bp product was amplified using an outer primer pair BTV1 and BTV4. The second amplification, using nested or internal primer pair BTV2 and BTV3, produced a 517-bp PCR product. RNA from North American prototype serotypes 2, 10, 11, 13 and 17, propagated in cell cultures, were detected by this nested PCR-based assay. The nested primers BTV2 and BTV3 increased the sensitivity of the BTV PCR assay, and as little as 0.1 fg of BTV RNA (equivalent to 5 viral particles) could be detected. Amplification products were not detected when the PCR-based assay was applied to RNA from a closely related orbivirus, epizootic hemorrhagic disease virus (EHDV) prototype serotypes 1 and 2; total nucleic acid extracts from uninfected BHK-21 cells; or whole blood from calves and deer that were BTV-seronegative and virus isolation negative. Application of this nested BTV PCR-based assay to clinical samples resulted in detection of BTV RNA from a variety of tissues collected from calves and deer with natural and experimental BTV infections. The described BTV PCR-based assay provides a valuable tool to study the epidemiology of BTV infection in susceptible wild ruminants and domestic livestock. 相似文献
78.
SG Carlier JP Marijnissen VL Coen WJ van der Giessen M Sabate J Ligthart A den Boer IE Céspedes W Li AF van der Steen PC Levendag PW Serruys 《Canadian Metallurgical Quarterly》1998,17(5):772-778
BACKGROUND/AIMS: The risk factors for esophageal variceal rebleeding are little known. Variceal pressure is one of the major determinants of variceal rupture, but the relationship between variceal pressure and variceal rebleeding during maintenance sclerotherapy has not been determined. This study was undertaken to evaluate the relationship between variceal pressure/gradient change and variceal rebleeding during maintenance sclerotherapy. METHODS: Patients with liver cirrhosis and recent esophageal variceal hemorrhage underwent consecutive variceal pressure measurements by direct puncture of the varices before each elective sclerotherapy. RESULTS: In 46 patients, the initial variceal pressure was no different regardless of age, sex, underlying etiology or hepatic reserve. Variceal pressure was higher in large varices, varices with more severe red wale markings, and varices with slower reduction in size during maintenance sclerotherapy. A larger volume of sclerosant was required to eradicate large varices, varices with more severe red wale markings, and varices with slower reduction in size during maintenance sclerotherapy. There was a positive correlation between initial variceal pressure and total amount of sclerosant (r=0.485, p=0.001). Initial variceal pressure was not related to rebleeding. Variceal pressure increased more in patients with rebleeding from varices per se (n=7) than in those without rebleeding (n= 24). There was no difference in pressure change between patients without rebleeding (n=24) and those with rebleeding from variceal ulcers (n=7). CONCLUSIONS: Large varices, severe red color signs and slow reduction in variceal size were associated with higher initial variceal pressure, and more sclerosant was required to eradicate the varices. An increase in variceal pressure during maintenance sclerotherapy indicates a higher risk of variceal rebleeding, but not of variceal ulcer rebleeding. 相似文献
79.
IE Kupriianov 《Canadian Metallurgical Quarterly》1998,114(5):91-93
Data concerning microscopic structure of the layers of human serous pericardium, localization of lymphoid structures as related to them and their interrelations with connective tissue elements and vessels are represented. Findings on the thickness of serous pericardium in different layers are also given. 相似文献
80.