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91.
It is occasionally difficult to record the standard 12-lead electrocardiograph (ECG) in emergency patients. The aim of this study was to evaluate the influence on electrocardiographic wave form recordings of moving the location of electrodes from the standard limb lead position to the trunk. The participants were 10 normal subjects and 20 patients with heart disease. In the new lead system, the limb electrodes were placed on the anterior acromial region and the anterior superior iliac spine using adhesive electrodes. Conventional 12-lead ECGs were recorded by the standard and the new lead system simultaneously in the supine position. Wave form analysis was done by an automatic analysis program. Motion artifacts in the recordings were less in the new lead system. The R wave amplitude of the new lead system increased in leads II, III and aVF, and decreased in leads I and aVL. However, the amplitudes of each wave obtained by standard electrocardiography and the new lead system correlated well (y = 1.008x + 2.038, r = 0.99, n = 2,880). In 99.6% of all wave forms, the differences in amplitudes were within 5% of the values of standard recordings. The average of differences in the ST-segment was 2.6 +/- 11.4 microV. The frontal plane QRS axis obtained by the new lead system showed a vertical shift of 7.8 +/- 8.5 degrees (y = 0.94911x + 10.346, r = 0.98, n = 30). The recording errors produced by the new lead system were within the permissible range of variation. The new lead system is a reasonable alternative for recording ECGs if application of the standard lead is difficult in an emergency.  相似文献   
92.
M Horikawa  Y Nakajima  K Kido  S Ko  K Ohashi  H Nakano 《Canadian Metallurgical Quarterly》1994,18(6):845-50; discussion 851
As a regional therapy for hepatic malignancy, we developed a simple method of isolated liver perfusion (hyperthermo-chemo-hypoxic). In the present study, the influence of this method on the hepatic tissue and other organs was experimentally evaluated and applied it to seven patients. Experimentally, all dogs survived without hepatic insufficiency and systemic toxicity. Clinically, one patient died on postoperative day 14 of hepatic failure. The reason was that liver temperature reached 43 degrees C, which seemed to be the maximum limit for thermal toxic effect to the human liver. The other six patients well tolerated the perfusion with mild increases of serum aminotransferase and total bilirubin levels and decreases of hepaprastin levels. Serum aminotransferase and total bilirubin and hepaprastin levels returned to normal levels by postoperative day 14. There were no significant differences between the isolated liver perfusion group (n = 7) and hepatectomy-only group (n = 27). Six patients were disease-free during the observation period after the perfusion. This system is a simple, useful method for treating patients with metastatic cancer limited to the liver.  相似文献   
93.
Accessible volume, geometrical area and accessible pore size distribution are the fundamental structural parameters in the characterization of porous solids. We provide a novel “inverse” procedure, which is based on the mass balance and an MC optimization scheme, to determine these parameters from the analysis of experimental adsorption isotherms for a number of commonly used activated carbons: BPL, AX-21 and Norit. Our results, based on a kernel of model pores generated from GCMC simulations, are compared with, and shown to be different from, the results obtained from the conventional method. We show that the discrepancies arise from an incorrect evaluation of both micropore and mesopore sizes.  相似文献   
94.
We prepared activated carbons from phenol-formaldehyde (PF) and urea-formaldehyde (UF) resins by chemical activation with K2CO3 with impregnation during the synthesis of the resins. The influence of carbonization temperature (773-1173 K) on the pore structure (specific surface area and pore volume) and the temperature range at which K2CO3 worked effectively as an activation reagent, were investigated. The specific surface area and micropore volume of PF-AC and UF-AC increased with an increase of carbonization temperature in the range of 773-1173 K. We prepared activated carbon with well-developed micropores from PF, and activated carbon with high specific surface area (>3000 m2/g) and large meso-pore volume from UF. We deduced the activation mechanism with thermogravimetry and X-ray diffraction. In preparing activated carbon from PF, K2CO3 was reduced by carbon in the PF char. The carbon was removed as CO gas resulting in increased specific surface area and pore volume above 1000 K. In preparing AC from UF, above 900 K the carbon in UF char was consumed during the K2CO3 reduction step.  相似文献   
95.
An in vitro nondestructive fatigue test was applied to adhesive posts and cores made on endodontically treated human teeth. Five post-and-core systems were evaluated: one zircon oxide post, two titanium posts (with resinous or ceramic coating), and two resin-fiber posts. Each test specimen was intermittently loaded and thermocycled. The scanning electron microscope observation of sample sections showed that only the interfaces between restorative materials and dentin exhibited substantial deficiencies. The Komet ER (Brasseler) exhibited the greatest percentages of continuity at the coronal (83.88%) or the radicular (78.12%) dentin levels, while the Zircon experimental post presented insufficient adaptation to the radicular (21.25% continuity) and to the coronal (53.25% continuity) dentin. Seven of eight samples in the Komet group showed root fractures. The carbon-fiber post (Composipost) behaved satisfactorily (67.38% radicular continuity), in spite of the use of an older bonding agent formulation.  相似文献   
96.
Fine ground powders of Nd-Fe-B sintered magnet bulks(particle size=46~125 μm in diameter) were coated and alloyed with Yb metal by sorbing them. A significant recovery of the decreased magnetic properties of the ground powders(remanence Br=~0.95 T, coercivity Hcj =~227 kA·m-1 and maximum energy product(BH)max=~48.8 kJ·m-3) was observed in accordance with increasing temperature up to 800 ℃. The sorbing temperature and time for Yb metal vapor were optimized and after heating at 800 ℃ for 90 min and annealing subsequently at 610 ℃ for 60 min, the Br, Hcj and(BH)max values were increased to be 0.98 T, 712 kA·m-1 and 173 kJ·m-3, respectively. From the microstructural characterizations of resulting samples by using X-ray diffraction(XRD), scanning electron microscopy(SEM), and electron probe X-ray microanalyzer(EPMA), it is found that the sorbed Yb metal uniformly covers the surface and diffuses to the Nd-rich grain boundary of fine ground powders of Nd-Fe-B sintered magnet bulks forming a(Nd,Yb)Fe2 phase.  相似文献   
97.
A fuzzy modeling method using fuzzy neural networks with the backpropagation algorithm is presented. The method can identify the fuzzy model of a nonlinear system automatically. The feasibility of the method is examined using simple numerical data.  相似文献   
98.
Local delivery of immunosuppressants to the graft and lymphatic tissue is a potential appraoch to enhance the immunosuppressive efficacy and to alleviate systemic adverse effects simultaneously. By taking advantage of this method, we developed liposomal FK506. Previous pharmacokinetic study of liposomal FK506 indicated increased FK506 levels in the liver and spleen. Because the liver is the site of the allograft in liver transplantation and the spleen is a major lymphoid tissue, we hypothesized that liposomal FK506 would increase immunosuppressive efficacy in liver transplantation. We evaluated this hypothesis in a canine model. Orthotopic liver transplantation was performed using beagle dogs, and the recipients were divided into the following groups: group I, no immunosuppression (n = 5); group II, 0.05 mg/kg/day of FK506 i.v. in a commercially available i.v. formulation for 14 days (n = 5); and group III, 0.05 mg/kg/day of FK506 i.v. in a liposomal formulation for 14 days (n = 5). All recipients in group I died within 2 weeks. Recipients in group II died within 33 days. In contrast, three recipients in group III survived for more than 200 days (P < 0.05 versus group I or group II). In DNA analysis, splenocyte proliferation activity in group III was significantly suppressed in comparison with group II. These results suggest that liposomal FK506 markedly increase the immunosuppressive efficacy of FK506 in liver transplantation. A local immunosuppressive effect in the grafted liver and significant suppression of splenocyte proliferation might contribute to enhancement of the immunosuppressive efficacy of liposomal FK506.  相似文献   
99.
Clinical and serological studies of chlamydial pneumonia were done in six patients (three men and three women). The other three patients had no avian contact and showed almost the same clinical symptom. Acute infection with Chlamydia psittaci and Chlamydia pneumoniae were diagnosed in two patients and in one patient, respectively, by MFA. Because in some cases Chlamydia psittaci pneumonia and Chlamydia pneumoniae pneumonia are difficult to differentiate, it is necessary to use a test that allows different chlamydia species to be distinguished.  相似文献   
100.
Adsorption isotherms and isosteric heats have been studied experimentally and by computer simulation for the krypton-graphitic hexagonal pore and krypton–graphite planar surface systems in the 60–109 K temperature range. The existence of a 2D transition in the sub-monolayer film on the basal plane of graphite that is observed experimentally is confirmed by the computer simulation results, but this transition is not observed in graphitic hexagonal pores because the onset of adsorption occurs at the junctions of adjacent pore walls, and the mechanism of surface adsorption is the spreading of adsorbate from the junction towards the basal planes until the first layer is completed. This is followed by molecular layering of higher layers, and then by capillary condensation when the empty core is small enough.  相似文献   
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