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11.
12.
We previously purified a nuclear localization signal binding protein, NBP60, from rat liver (1993, J. Biochem. 113, 308-313). In this study, the subcellular localization of NBP60 was examined using anti-NBP60. Most NBP60 was found to be localized in the nuclear envelope fraction of rat liver obtained on cell fractionation followed by immunoblotting. Staining of the nuclei of cultured cells by the antibody was observed on immunofluorescence microscopy. NBP60 was widely detected in rat nuclear fractions prepared from other tissues and also in nuclei of cultured cells derived from other species. It was shown by immunoelectron microscopy that most NBP60 is present in the nuclear envelope and at least some of that is present on nuclear pore complexes. Although NBP60 was localized in the nuclear envelope in interphase cells, it diffused into the cytoplasm in the mitotic phase. The purified NBP60 was highly phosphorylated by a cdc2 mitotic kinase, whereas nuclear pore proteins p144, p62, p60, and p54 were not phosphorylated by the kinase directly. NBP60 was also phosphorylated by protein kinase A, calmodulin-dependent protein kinase II, and casein kinase II. The phosphorylation of NBP60 by cdc2 kinase and/or the other kinases may be related to the change in the protein's location during the mitotic phase.  相似文献   
13.
We have developed a low-temperature fabrication process (⩽ 200°C for high-quality polycrystalline Si thin-film transistors (poly-Si TFTs) on flexible stainless-steel foils. The fabrication processes is realized through sputter deposition of thin films, including active-Si and gate-SiO2 films, crystallization of Si films by KrF excimer laser irradiation, and inductively coupled plasma hydrogenation. High-quality n- and p-channel poly-Si TFTs are successfully fabricated without suffering from problems of substrate bending, film ablation, or cracking in films. The resulting n- and p-channel poly-Si TFTs showed mobilities of 106 and 122 cm2/V·s, respectively. This paper describes the deposition and properties of the sputtered Si films and the fabrication process and electrical characteristics of the poly-SiTFTs  相似文献   
14.
Recently, large-capacity power stations have been built far from load centers with long-distance transmission lines. Therefore, if a fault occurs at the line, generators in the large-capacity power station may lose synchronism from the remaining generators [1, 3]. To prevent an extension of loss of synchronism to other generators, fast shedding of some generators is an effective measure. The following methods have been proposed so far: A method [3] based on energy function approach; and a method [2] which estimates and predicts the relative swing among generators using data measured on-line at each generator and proposes shedding some generators for stabilization. This method requires a large communication network for an exchange of data between power stations. This paper presents a new stabilizing method and a newly developed stabilizing control system which does not require a large communication network because it utilizes generator output, voltage and current measured on-line in the vicinity of the large-capacity power station. Using these measured data, the system estimates and predicts the relative swing between generators in the large-capacity power station and the remaining generators. Finally, the number of generators to be shed for stabilization is decided and shedding is performed. Configuration and characteristics of the developed stabilizing control system are shown. The validity of this method is confirmed by simulation and testing using an artificial power system.  相似文献   
15.
Sn(II)1.2(Nb(V)1.6Sn(IV)0.4)O6 pyrochlore precursor was oxidized at temperature of the range 573–973 K in 1% O2/Ar and O2 gases for various periods of time. Two kinds of novel metastable phases with a composition of Sn(IV)0.6(Nb(V)0.8Sn(IV)0.2)O3.6 could be synthesized. Further, the other novel metastable phase with the same composition was found as a phase contained. One of the metastable phases was the cubic κ-CeZrO4 related-type possessing the fluorite-related structure, which was formed by the cation diffusionless insertion of the oxygen atom into original oxygen vacant site of the pyrochlore-type structure. Another was an orthorhombic α-PbO2 related-type possessing a cation ordered arrangement unlike a well known NiWO4 structure. The other was the rutile related-type possessing a cation ordered arrangement. Appearance of the two latter metastable phases could be attributed to the displacement of the oxygen stacking in the κ-CeZrO4 related-type phase without cation redistributions. The appearance mechanisms were analogous to the well known transformations for AX2 compounds among rutile-type, α-PbO2-type, and fluorite-type phases under high pressure and its release. The dependence of the appearance of these novel metastable phases on oxygen partial pressure and temperature has been discussed in terms of the driving forces and energy barriers for reactions.  相似文献   
16.
Three adult Japanese cases of Gitelman's syndrome were characterized by secondary aldosteronism, hypokalemic alkalosis, hypomagnesemia, and hypocalciuria. Two were revealed to be familial cases. A mutation in the thiazide-sensitive Na-Cl cotransporter gene, which had already been confirmed in one family (Takeuchi et al. J Clin Endocrinol Metab 81: 4496,1996), was not detected in the other two cases. These observations may possibly support the previous report (Simon et al. Nature Genet 12: 24, 1996) that Gitelman's syndrome is caused by a variety of mutations in the thiazide-sensitive Na-Cl cotransporter.  相似文献   
17.
To determine the risk of death at an early stage of fulminant viral hepatitis, we created severity indexes drawn from clinical data on the day of development of encephalopathy in 128 patients with fulminant hepatitis B and 103 with fulminant hepatitis non-A, non-B. In fulminant hepatitis B, the risk score was 2.75 x BL + 2.75 x BR + 2.7 x AG + 2.3 x WB + 1.67 x CD + 1.56 x AL - 0.098 x PR - 0.88, where BL is 1 if total bilirubin is higher than 20 mg/dl, BR is 1 if the ratio of total to direct bilirubin exceeds 2.2, AG is 1 if age is above 40 yr, WB is 1 if white blood cell count is less than 4,000 cells/mm3 or more than 18,000 cells/mm3, CD is 1 if a hazardous disease coexists and AL is 1 if ALT is less than 100 times the upper limit of normal (otherwise all are 0), and PR is prothrombin time (percentage of normal value). Using a cutoff score of 0, we found the positive predictive value, negative predictive value and predictive accuracy to be 0.90, 0.86 and 0.89, respectively. Sensitivity and specificity were 0.94 and 0.77, respectively. In fulminant non-A, non-B hepatitis, the risk score was 2.66 x BR + 2.25 x BL + 2.24 x DI + 2.05 x AL +/- 1.38 x AG + 0.00021 x WB - 6.33.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
18.
The effects of acetylcholine (ACh) and histamine (His) on the membrane potential and current were examined in JR-1 cells, a mucin-producing epithelial cell line derived from human gastric signet ring cell carcinoma. The tight-seal, whole cell clamp technique was used. The resting membrane potential, the input resistance, and the capacitance of the cells were approximately -12 mV, 1.4 G ohms, and 50 pF, respectively. Under the voltage-clamp condition, no voltage-dependent currents were evoked. ACh or His added to the bathing solution hyperpolarized the membrane by activating a time- and voltage-independent K+ current. The ACh-induced hyperpolarization and K+ current persisted, while the His response desensitized quickly (< 1 min). These effects of ACh and His were mediated predominantly by m3-muscarinic and H1-His receptors, respectively. The K+ current induced by ACh and His was inhibited by charybdotoxin, suggesting that it is a Ca(2+)-activated K+ channel current (IK.Ca). The measurement of intracellular Ca2+ ([Ca2+]i) using Indo-1 revealed that both agents increased [Ca2+]i with similar time courses as they increased IK.Ca. When EGTA in the pipette solution was increased from 0.15 to 10 mM, the induction of IK.Ca by ACh and His was abolished. Thus, both ACh and His activate IK.Ca by increasing [Ca2+]i in JR-1 cells. In the Ca(2+)-free bathing solution (0.15 mM EGTA in the pipette), ACh evoked IK.Ca transiently. Addition of Ca2+ (1.8 mM) to the bath immediately restored the sustained IK.Ca. These results suggest that the ACh response is due to at least two different mechanisms; i.e., the Ca2+ release-related initial transient activation and the Ca2+ influx-related sustained activation of IK.Ca. Probably because of desensitization, the Ca2+ influx-related component of the His response could not be identified. Intracellularly applied inositol 1,4,5-trisphosphate (IP3), with and without inositol 1,3,4,5-tetrakisphosphate (IP4), mimicked the ACh response. IP4 alone did not affect the membrane current. Under the steady effect of IP3 or IP3 plus IP4, neither ACh nor His further evoked IK.Ca. Intracellular application of heparin or of the monoclonal antibody against the IP3 receptor, mAb18A10, inhibited the ACh and His responses in a concentration-dependent fashion. Neomycin, a phospholipase C (PLC) inhibitor, also inhibited the agonist-induced response in a concentration-dependent fashion. Although neither pertussis toxin (PTX) nor N-ethylmaleimide affected the ACh or His activation of IK,Ca, GDP beta S attenuated and GTP gamma S enhanced the agonist response.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
19.
In twenty eight patients with iron deficiency the efficacy of iron-acetil-transferrin treatment (2-3 mg/kg/die) has been evaluated from the changes of the following variables: RBC and reticulocyte count, Hb concentration, MCV, MCH, serum ferritin, serum iron, TIBC, and ZnPP. These variables were assessed before and after three months of treatment in all patients, and after three months from the end of the treatment in thirteen patients. At the end of the treatment there was a significant increase of RBC count, Hb concentration, MCV, MCH, serum ferritin, serum iron, and TIBC, a significant decrease of ZnPP, while reticulocyte count remained essentially unchanged. After three months from the end of the treatment only serum ferritin and ZnPP underwent an additional significant increase and decrease, respectively. In twenty-six patients serum ferritin values returned to normal. The changes of RBC and reticulocyte count, Hb concentration, MCV, serum iron, and TIBC were larger the lower the initial values, suggesting that the efficacy of the treatment is greater the more serious the iron deficiency.  相似文献   
20.
An ultrasound-based remote sensing method to evaluate the mechanical properties of materials is presented. This method consists of a disk-shaped, piezoelectric transducer, operating at its resonance frequency, and a phase-shifted, feedback circuit. Mechanical parameters are derived by analyzing the signal contained in the phase-shifted values of the reflected signal. It is concluded that, using this novel transducer system and signal processing, remote mechanical measurements can be made. Such measurements obviate the need to apply the force-deformation approach and may be used to enable stiffness imaging.  相似文献   
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