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1.
Adhesion is one of the bacterial strategies indispensable for colonization of the small intestine. Food components reaching the small intestine, are not only digested and absorbed there, but may also influence the microorganisms colonizing the mentioned region. In this way, nutrients, particularly the ones the enzymatic degradation of which is hindered, acquire the ability to modify the adhesive potential of the autochthonic microorganisms. The glycated food proteins are noteworthy here for they often undergo relevant structural and functional alterations. Such proteins tend to display a lowered susceptibility to enzymatic degradation and thus may act as modulators of both metabolic activity and adhesive potential of bacteria adhered to the intestinal cells. For that reason, this study aimed at establishing the impact of the glycated pea proteins on adhesion of the bacteria from the genera: Lactobacillus, Enterococcus, and Escherichia, which are typical for the human small intestine.  相似文献   
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The kinetics of the simultaneous isomerization and hydrogenation of glucose are studied, and the experimental results are described with a simplified reaction model. By simulating the course of the reactions with a computer the rate constants were determined, and the energies of activation were calculated. From an Arrhenius plot the apparent isomerization activation energies were deduced. Under the experimental conditions a yield of 27% mannitol was obtained starting from glucose. Higher yields can be obtained at low temperatures and low catalyst concentrations.  相似文献   
4.
Two opioid peptides with agonistic (β-casomorphin-5 and β-casomorphin-7) and three with antagonistic (casoxin-6, casoxin-C and lactoferroxin A) activity were determined in three semi-hard cheeses (Edamski, Gouda and Kasztelan) and in two ripening mould cheeses (Brie and Rokpol). β-Casomorphins (BCMs) were found at a higher level in the mould cheeses, whereas the opioid peptides with antagonistic activity were identified at a higher level in the semi-hard cheeses. The opioid activities of the peptide extracts from the cheeses were confirmed using isolated rabbit ileum.  相似文献   
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Si-doped β-Ga2O3 was generally activated by high-temperature annealing (over 600?°C) due to its strong bonding energy. Considering the electronic applications using β-Ga2O3 such as various power devices with low power consumption, it is strongly required to decrease the device process temperature including the impurity activation process. In this article, in order to decrease the impurity activation process temperature, we proposed the rapid thermal annealing (RTA) treatment to activate the Si atoms in the β-Ga2O3 films since RTA treatment can give the high thermal energy to specimen in a short time and investigated the influence of RTA treatment with various temperatures on conductivity activation energy, and structural properties of Si-doped β-Ga2O3 film. Si-doped β-Ga2O3 films were hetero-epitaxially grown on c-plane sapphire substrate by pulsed laser deposition method. Crystallinity, surface roughness, and electrical properties of specimens were investigated by changing the RTA temperatures. Crystallinity and surface roughness of Si-doped β-Ga2O3 films were not significantly influenced by RTA treatment at temperatures range of 100–700?°C. Conductivity activation energy of specimens with RTA treatment was about 50–100?meV and did not depend on RTA temperatures. As a result, even Si-doped β-Ga2O3 film with RTA treatment at 100?°C showed a relatively good conductivity. Based on the experimental results in this study, it can be said that RTA treatment is useful method to decrease the temperature of activation process for Si-doped β-Ga2O3 thin films without serious structural degradations.  相似文献   
6.
Germ-cell mutagenesis has been studied in male lambda lacZ transgenic mice in such a way that the data can be compared with literature data for germ-cell mutagenesis obtained with the specific-locus test (SLT). Mutagenesis induced by ethylnitrosourea (ENU), ethylmethanesulphonate (EMS), methylnitrosourea (MNU) and methylmethanesulphonate (MMS), has been studied in mature spermatozoa isolated from the epididymis and vas deferens. In order to investigate mutagenesis in different phases of spermatogenesis, animals were sacrificed at various time points after treatment. ENU at 150 mg/kg body weight significantly induced mutations in stem cells (analysis at 100 days post-treatment), but not in post-stem cells (7 days post-treatment). EMS (250 mg/kg) and MMS (60 mg/kg) induced mutations only in post-stem cells (7 days), but not in stem cells (100 days). MNU (70 mg/kg) resulted in an increase of mutations in both post-stem cells (14 and 37 days) and stem cells (100 days), although the latter, due to a limited number of data, was not statistically significant. All these data are in accordance with published SLT data. These results indicate that lambda lacZ transgenic mice are a suitable model to study gene mutations in different phases of spermatogenesis.  相似文献   
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Spontaneous proliferative liver lesions were found in 15 (13 males and 2 females) of 244 (122 of each sex) transgenic (Tg) mice carrying the human prototype c-H-ras gene (rasH2). The liver lesions included 3 foci of cellular alteration, 1 hepatocellular adenoma, 5 hepatocellular carcinomas, and 4 hepatic hemangiosarcomas in the males and 1 focus of cellular alteration and 1 hepatocellular carcinoma in the females. The mutation patterns of the human and endogenous mouse c-H-ras codon 61 in these proliferative liver lesions were analyzed by DNA amplification using polymerase chain reaction, single-strand conformation polymorphism (PCR-SSCP), and oligonucleotide dot blot hybridization. The hepatocellular carcinomas in 4 males and 1 female contained a point mutation in the mouse c-H-ras gene: 3, 1, and 1 carcinomas had a CAA to AAA transversion at the first base of codon 61, a CAA to CTA transversions, and a CAA to CGA transition at the second base of codon 61, respectively. No point mutations in the human c-H-ras transgene were detected in any hepatocellular carcinoma. All 4 hepatic hemangiosarcomas had a CAG to CTG transversion at codon 61 of the human c-H-ras gene, but no point mutations were detected in codon 61 of the mouse c-H-ras gene. No mutations in human or mouse c-H-ras codon 61 were detected in altered cell foci or hepatocellular adenoma. These results indicate that spontaneous liver tumors in rasH2 Tg mice contain different mutation patterns depending on the histologic type or cell origin of the tumors (i.e., hepatocellular carcinomas or hepatic hemangiosacomas). The absence of similar mutations in foci of cellular alteration and the hepatocellular adenoma suggests that the occurrence of codon 61 point mutations is a late event in the progression of hepatocellular neoplasia in rasH2 Tg mice.  相似文献   
8.
n-ZnO/n-GaAs heterostructured light-emitting diodes have been fabricated by a low-cost ultrasonic spray pyrolysis technique. Nanoscale interface analysis was carried out with scanning transmission electron microscopy. An ~ 8.6-nm-thick amorphous GaAsZnInO was found in the n -ZnO/n-GaAs interface. A strong and broad white electroluminescence band centered at ~ 525 nm and a weak near-infrared emission peaked at ~ 815 nm were observed when n-GaAs was positively biased. The 815-nm emission is believed to be related to the interface layer, and the 525-nm emission is assigned to the recombination of electrons from conduction band to deep-level holes in the ZnO layer.  相似文献   
9.
Ermittlung der Zinkaktivität in Mangan-Zink- und Eisen-Zink-Schmelzen. Darstellung der Aktivitätsverläufe im System Mn–Zn für 1300°C und Molenbrüche bis zu xZn = 0,04 sowie im System Fe–Zn für 1585°C und Molenbrüche bis zu xZn = 0,005.  相似文献   
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