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1.
To clarify the role of phosphate in the formation of corrosion products, the transformation of GRI(Cl) with the addition of phosphate was characterized through XRD, TEM, and solution analysis. Electrochemical analysis showed that the transformation of GRI(Cl) was delayed and the size of the final products, i.e., γ-FeOOH was reduced in the phosphate added case. X-ray absorption spectroscopy indicated that the neighboring Fe–Fe coordination number of FeO6 octahedral unit in γ-FeOOH was decreased. These effects of phosphate are attributed to its adsorption on GRI(Cl) and nucleated γ-FeOOH that prevented particle growth during oxidation process.  相似文献   
2.
To investigate the contribution of ions to gas nucleation, we have performed experiments on the formation of water droplets in H2O/N2 and H2O/Ar gas mixtures by irradiation with a 20 MeV proton beam and by positive corona discharge. The size of the formed nanoparticles was measured using a differential mobility analyzer equipped with a Faraday cup electrometer. Using the proton beam, droplets around 10 nm in diameter were observed for both positively and negatively charged particles, but none were found when the corona discharge was used. This implies the importance of the presence of both positive and negative ions for the formation of nanosize droplets, which attract each other by Coulomb interactions, enhancing the collision frequency and leading to the formation of the 10 nm droplets.  相似文献   
3.
Thyroid hormone receptors (TRs) are members of the steroid hormone receptor superfamily and are encoded by two different genes, alpha and beta. Three isoforms (alpha 1, alpha 2, and alpha 3) are created by alternative splicing of the TR alpha gene. In TR alpha 2 and alpha 3, the distal half of the putative dimerization domain is disrupted and the carboxy terminus of the protein is substituted with different amino acids. To evaluate the properties of these alterations in the dimerization region, DNA binding and dimerization of TR alpha isoforms were studied by electrophoretic mobility shift assays. TR alpha 1 formed a monomer or a homodimer on certain thyroid hormone responsive elements (TREs), whereas TR alpha 2 and alpha 3 did not bind effectively to any of the TREs studied. TR alpha 1 formed a heterodimer with 9-cis retinoic acid receptor alpha (RXR alpha) on all TREs studied. Although TR alpha 2 did not bind as a homodimer, it did bind as a heterodimer with RXR alpha to DR4 and MHC-TRE. TR alpha 3 bound as a heterodimer to a broader repertoire of TREs, including DR4, MHC, ME, and F2-TRE. These results indicate that the alterations in the dimerization region in TR alpha 2 and alpha 3 abrogated homodimer binding, but differentially affected heterodimerization with RXR alpha on various TREs.  相似文献   
4.
The present study was performed to determine the relation between oxygenated hemoglobin (oxy-Hb) changes in working muscles and ventilatory parameters. Six active normal subjects, 21 sedentary normal subjects and 16 patients with heart failure performed an incremental exercise with expired gas analysis. Deoxygenation of the vastus lateralis muscle was monitored for oxy-Hb changes using near-infrared spectroscopy. Near the anaerobic threshold (AT), oxy-Hb started to decrease, forming the first inflection point (P1). Near the respiratory compensation point (RCP), the second inflection point (P2) was observed. Oxygen uptake at the AT, RCP, P1 and P2 decreased in magnitude first in the active normal subjects, then in sedentary normal subjects and finally in the heart failure patients. High correlation was demonstrated between AT and P1 (r=0.8, p<0.0005) and between RCP and P2 (r=0.9, p<0.0005). In 12 sedentary normal subjects who underwent repeat exercise, reproducibility was confirmed for both P1 and P2. Constant work rate exercises were performed in 5 sedentary normal subjects, and in all of them the oxy-Hb remained unchanged below the AT work rate, whereas oxy-Hb decreased above the AT work rate. Exercise capacity, with respect to both working muscle deoxygenation and ventilation, could be evaluated in detail by the concomitant use of near-infrared spectroscopy and expired gas analysis.  相似文献   
5.
The purpose of this study was to investigate the use of hepatocyte growth factor as a biochemical marker for acute myocardial infarction. Several biochemical markers are used for noninvasive detection of acute myocardial infarction. However, hepatocyte growth factor has not been used previously for this purpose. We measured hepatocyte growth factor, creatine phosphokinase, and MB isoenzyme (CK-MB) levels in 6 patients with stable effort angina after diagnostic catheterization (controls) and in 12 patients with acute myocardial infarction (AMI). The measurements in the AMI patients were recorded twice a day for the first 3 days after onset of chest pain and once a day for the next 4 days. Furthermore, in each patient we evaluated the time to reach the maximum level and the time for the level to decline to less than half the maximum. Hepatocyte growth factor levels (ng/ml) were 0.3+/-0.1 for angina pectoris patients, and 15.7+/-9.1 within 6h and 12.5+/-4.6 within 12h after the onset for AMI patients, respectively. The correlation coefficients between hepatocyte growth factor and creatine phosphokinase and between hepatocyte growth factor and CK-MB were 0.68 and 0.74, respectively. The time to reach the maximum (h) and the time to decline to less than half of the maximum level (days) were 6.6+/-2.6 and 1.2 +/-0.2 for hepatocyte growth factor, 19.4+/-8.7 and 2.5+/-1.4 for creatine phosphokinase, and 16.6+/-7.7 and 1.5+/-0.4 for CK-MB, respectively. Hepatocyte growth factor is useful as a prognostic indicator and reflects the clinical course in patients with acute myocardial infarction.  相似文献   
6.
Platelet-derived endothelial cell growth factor (PD-ECGF) was isolated as an endothelial cell mitogen from platelets. In this study, we investigated the expression of PD-ECGF and counted microvessels in 58 oral and oropharyngeal squamous cell carcinoma (SCC) specimens by an immunohistochemical technique to examine their prognostic significance and performed tumor in vitro sensitivity to 5-fluorouracil (5-FU) and cisplatin as determined by a bioluminescence assay of the ATP values of tumor cells after continuous exposure. The percentage of PD-ECGF-positive tumor cells (PD-ECGF score) was correlated with the frequency of the recurrence of disease (P=0.0043) but not with sex, tumor size, metastasis, or clinical stage. Overall survival of the high PD-ECGF expression group (>40% PD-ECGF score) was shorter than the low expression (<40%) group (P=0.0365). Vessel count was correlated with lymph node metastasis and clinical stage. The survival of patients with hypervascularity (more than the median of intratumor vessel counts, >82) was shorter than that of those with hypovascularity (vessel count <81, P=0.0446). However, there was no association between PD-ECGF expression and vessel count. Cox proportional multivariate analysis showed that PD-ECGF expression was the most significant independent prognostic indicator for overall survival. The susceptibility to 5-FU cytotoxicity in the extremely high PD-ECGF expression groups (>70% of PD-ECGF score) was significantly higher than that in the low group, whereas there was no difference in their sensitivity to cisplatin. These results showed that carcinoma cells with high PD-ECGF expression were sensitive to 5-FU in spite of poor prognosis. These data provide further information when deciding on adjuvant therapy for oral and oropharyngeal SCCs.  相似文献   
7.
Vascular parkinsonism is thought to be a distinct parkinsonian syndrome associated with small deep infarcts and white matter lesions (WMLs). We studied the prevalence of parkinsonian features (bradykinesia, rigidity, tremor, and gait disorder) in relation to small deep or territorial infarcts and WMLs on computed tomography (CT) in 62 lacunar and 41 territorial stroke patients, at 3.0 (median) years of follow up. One or more parkinsonian signs were found in 36% of these patients; 11% clinically had parkinsonism. Parkinsonian signs were found more frequently in lacunar than in territorial stroke patients: bradykinesia in 45% and 7%, rigidity in 13% and 7%, tremor in 6% and 7%, and gait disorder in 16% and 7%, respectively. Patients with WMLs at study entry (n = 16) were compared with those without WMLs (n = 87): 56% and 25% had bradykinesia, 25% and 8% rigidity, 25% and 3% tremor, and 38% and 8% gait disorder, respectively. Regression analysis with adjusted odds ratios ([a]OR) showed that WMLs at study entry were associated with bradykinesia ([a]OR 8.0, 95% confidence interval [CI] 1.6-41.6), gait disorder ([a]OR 7.1, 95% CI 1.5-33.7), and tremor ([a]OR 7.0, 95% CI 1.2-40.3). Bradykinesia was associated with lacunar stroke at study entry ([a]OR 11.5, 95% CI 2.4-54.9). Thus, one third of our stroke patients had one or more parkinsonian signs, and 10% clinically had a parkinsonian syndrome that differed from Lewy body parkinsonism: infrequent resting tremor, but frequent gait disorder. Parkinsonian signs were associated with WMLs and lacunar stroke. Therefore, this study favors a distinct vascular parkinsonian syndrome.  相似文献   
8.
Granulocyte colony-stimulating factor receptors (G-CSFRs) have been observed on the surface of not only hematopoietic cells but also several cancer cells. The stimulation of G-CSF has been demonstrated to induce proliferation and activation of G-CSFR-positive cells. In this study, we investigated the expression of G-CSFR on the surface of tumor cells and G-CSF production in oral and mesopharyngeal squamous cell carcinoma (SCC) by an immunohistochemical approach. Of 58 oral and mesopharyngeal SCCs, 31 cases (53.4%) and 36 cases (62.1%) were positive for G-CSFR and G-CSF, respectively. There was no association between G-CSFR expression and G-CSF staining. In the group positive for G-CSFR expression, relapse was significantly more likely after primary treatment (P = 0.0069), whereas there was no association between G-CSFR expression and age, sex, tumor size, lymph node metastasis, and clinical stage. Also, the G-CSFR-positive groups had a significantly lower disease-free and overall survival rate than the G-CSFR-negative groups (P = 0.0172 and 0.0188, respectively). However, none of the clinical markers correlated significantly with G-CSF staining, nor did the status of G-CSF production influence the overall survival. The results imply that assessment of G-CSFR may prove valuable in selecting patients with oral and mesopharyngeal SCC for aggressive therapy.  相似文献   
9.
Fingerprint input based on scattered-light detection   总被引:1,自引:0,他引:1  
Fujieda I  Haga H 《Applied optics》1997,36(35):9152-9156
The principles of fingerprint imaging are based on scattered-light detection, and the technique is proposed for a compact input device. Light enters a glass plate from its edge and propagates inside the plate by repeating the total internal reflection at the boundaries with air. The ridges of a finger pressed onto the plate scatter the light, which then leaks out of the plate. This scattered light is imaged by an array of gradient-index optical fibers and an image sensor. A prototype sensor has been developed: The distance between the finger and the image sensor is 13 mm. The images obtained with this prototype clearly show not only the ridges and valleys but also the pores in the ridges.  相似文献   
10.
Two-way satellite time and frequency transfer (TWSTFT) is one of the main techniques used to compare atomic time scales over long distances. To both improve the precision of TWSTFT and decrease the satellite link fee, a new software-defined modem with dual pseudo-random noise (DPN) codes has been developed. In this paper, we demonstrate the first international DPN-based TWSTFT experiment over a period of 6 months. The results of DPN exhibit excellent performance, which is competitive with the Global Positioning System (GPS) precise point positioning (PPP) technique in the short-term and consistent with the conventional TWSTFT in the long-term. Time deviations of less than 75 ps are achieved for averaging times from 1 s to 1 d. Moreover, the DPN data has less diurnal variation than that of the conventional TWSTFT. Because the DPN-based system has advantages of higher precision and lower bandwidth cost, it is one of the most promising methods to improve international time-transfer links.  相似文献   
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