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41.
Adjuvant activity of saponins extracted from the South American tree Quillaja saponaria has been demonstrated with many antigens. Recently, four saponin fractions (designated as QS-7, QS-17, QS-18, and QS-21) with adjuvant activity were purified by reverse phase chromatography. In particular, efficacy of the less toxic QS-21 fraction has been demonstrated with several recombinant viral antigens including HIV gp120. Here, we report a novel saponin fraction (designated as QS-L1) derived from Quillaja saponaria. Unlike previously identified saponins, QS-L1 had a different chemical structure and showed adjuvant activity only when administered in the presence of alum-precipitated antigen. Interestingly, the QS-L1 greatly increased not only a humoral immune response but also cellular immune response to recombinant hepatitis B virus surface antigen (HBsAg). Furthermore, QS-L1 showed lower toxicity in vivo and in vitro than the previously identified saponin fraction, QS-21. Finally, we examined the chemical structure of the QS-L1 using mass spectroscopic analysis, carbohydrate composition analysis and NMR spectroscopic analysis. Thus, our results indicated that this novel QS-L1 saponin fraction had several desirable properties required for an effective adjuvant.  相似文献   
42.
Clinical background was investigated on patients with urinary tract infections (UTIs) from whom 785 bacterial strains were isolated in 11 hospitals during the period from June, 1995 through May, 1996. 1. Distributions of age and sex of patients and type of infections. Among the patients examined, those with ages 50 years or older were the most frequent (males: 80.5%, females: 69.7%), and, among females, those with ages in the 20's were 12.6%. With regard to types of infections, more than a half of infections among males were of complicated types, but most of infections among females were of uncomplicated types, especially among females of ages less than 60 years. 2. Ages of patients and types of pathogens. The higher the ages of patients, the lesser became the isolation frequencies of Proteus spp. and Serratia spp., but the higher were those of Klebsiella spp. and Pseudomonas spp. 3. Effect of antibiotic use on isolation frequencies of pathogens. Use of antibiotics decreased pathogens isolated from patients with uncomplicated UTIs drastically (237 isolates before antibiotics compared to 33 after). Even isolated pathogens from patients with complicated UTIs decreased drastically with the use of antibiotics when indwelling catheters were not in use (200 isolates before antibiotics compared to 83 after), but when indwelling catheters were in use, antibiotics apparently failed to decrease the isolation frequency. 4. Surgical procedures and types of causative organisms for UTIs. Escherichia coli was the most frequently isolated organism from uncomplicated cases of UTIs. From cases of complicated UTIs without indwelling catheters, Enterococcus faecalis was the most frequently isolated, followed by E. coli, P. aeruginosa and Klebsiella spp. When a surgical procedures were not done, E. coli was isolated most frequently. From cases of complicated UTIs with indwelling catheters, P. aeruginosa, E. faecalis and S. aureus were the organisms that were mainly isolated, with isolation frequencies of 23.9%, 17.3% and 12.7%, respectively. When no surgical procedures were used, isolation frequencies of P. aeruginosa, Klebsiella spp. and E. faecalis were 25.7%, 14.3% and 14.3%, respectively.  相似文献   
43.
In this paper, both high temperature strength and inelastic behavior of plate–fin structures were discussed for applying these structures to the compact heat exchangers such as recuperative and intermediate heat exchangers for high-temperature gas-cooled reactors (HTGR). Firstly tensile, creep and fatigue tests of the brazed plate–fin model of small size were carried out to obtain the rupture strength and inelastic behavior. The influence of the braze filler metal thickness on the tensile strength was experimentally studied and a possibility of predicting both the tensile and creep strength was discussed using the data of base material of plates and fins. Secondly, we demonstrated the fabrication of large-size core with a dimension of 1000 mm, and also demonstrated that the bonding ratio in this core was improved up to almost 100% by adopting the pressurized tank system in the brazing process. Finally, we proposed the stress analysis method of plate–fin structures on the basis of the equivalent-homogeneous-solid concept, and carried out the elastic–plastic analysis of recuperative heat exchanger for HTGR. Characteristics of stress–strain behavior were discussed together with a possibility of predicting the fatigue life of the structure.  相似文献   
44.
A study is performed on the creep analysis of perforated plates based on the equivalent solid plate concept.A series of creep analyses by FEM for various materials, ligament efficiencies and loading conditions is performed on a perforated plate with a triangular penetration pattern of circular holes. Based on the results of the analysis, prediction methods for both the equivalent solid plate property and the stress-strain concentration around the hole are proposed.The prediction method for the equivalent solid plate property is compatible with the elastic property shown in the ASME B&PV Code Sec. III A-8000. The prediction method for the stress—strain concentration is based on Neuber's rule together with Hoff's analogy, and is compatible with the elastic peak stress multiplier in the ASME B&PV Code Sec. III A-8000.  相似文献   
45.
CDDP/5'-DFUR combination chemotherapy was performed on 17 patients with non-resected and recurrent gastric cancer (clinical stage were IVb in all patients). They were treated with 1,400 mg/m2 of 5'-DFUR on days 1-4 orally following by withdrawal 10 days, every 2 weeks repeatedly and 80 mg/m2 of CDDP (c. i. v., on day 5, every 4 weeks). This chemotherapy was performed for at least 2 courses on all patients. Eight of 17 patients achieved a partial response and the overall response rate was 47.1% (differentiated type 57.1%, undifferentiated type 45.5%). Response rates of each lesion were as follows: primary foci 42.9%, abdominal lymph nodes 57.1%, hepatic metastasis 60.0% and ascites 33.3%, respectively. Improvement of performance status was seen in 12 of 17 patients (70.6%). The overall median survival time was 227 days. The median outpatient period was 113 days. There was no high-grade toxicity over grade 2. Therapeutic toxicity of grade 2 was manifested as renal dysfunction (23.5%), nausea/vomiting (17.6%), leukopenia (5.9%) and anemia (5.9%). We evaluated the therapeutic effect by visual examination after completion of the second course. However, poor effect and high incidence of renal dysfunction were found in patients treated with this therapy over four times. Therefore, the maximum effect seemed to be revealed after completion of the fourth course. From the present study, CDDP/5'-DFUR combination chemotherapy seems to be effective for patients with high-grade advanced gastric cancer and improved their quality of life.  相似文献   
46.
To induce a pulsatile flow in a centrifugal pump, we developed a new device (pulsatile assist device for centrifugal pump: PADCP) using a new concept. This device consists of a flexible polyurethane tube with an air chamber which is connected to the arterial side of the centrifugal pump circuit directly. A mock circulation system was used for evaluation of this PADCP. Thirty to 40 mm Hg of pulse pressure was obtained under 3-6 L/min of flow rate. By increasing the driving pressure of the PADCP from 200 to 600 mm Hg in a mock system, 4-48 mm Hg of pulse pressure was gained accompanied by a decrease in pump flow and increased left atrial pressure. The decreased pump flow and increased left atrial pressure were recovered easily by increasing the flow rate of the centrifugal pump. Pressures at the proximal site of the PADCP were less than 500 mm Hg. The PADCP was useful to induce a pulsatile flow in a centrifugal pump.  相似文献   
47.
A 28 year-old man was admitted to our hospital because of fever, cough and chest pain. A chest X-ray film taken on admission showed infiltrate in the left upper lung field with ipsilateral pleural effusion. Microscopical examinations of stained specimens of sputa and pleural effusions disclosed no acid-fast bacilli. The level of adenosine deaminase (ADA) in pleural effusion was 46.4 IU/l. A tuberculin skin test was moderately positive. The most probable diagnosis was pulmonary tuberculosis with pleural effusion. Isoniazid (INH) and rifampicin (RFP) were administered on the 5th hospital day and continued to lower the fever and reduce the pleural effusion. The cultured specimens of sputa and pleural effusions yielded Mycobacterium kansasii. After six months of treatment, chest X-ray film showed improvement and the administration of INH, RFP was discontinued without recurrence.  相似文献   
48.
Utilising the random-fracture-resistance model of grain boundaries, micro-macro combined creep damage simulation was applied to the prediction of the distribution of small defects in the FGHAZ (fine-grained heat-affected zone) of longitudinal welds in an actual-size elbow of modified 9Cr-1Mo (9Cr-1MoVNb) steel subject to internal pressure at 923 K. Based on the simulation results, a prediction scheme for the final rupture life of welds was considered using the damage mechanics concept together with effective stress. The applicability of nonlinear fracture mechanics was also discussed, assuming the initial crack length determined from the microscopic simulation results. The results thus obtained are summarized as follows: As the simulation results showed, the peaks of small defect density in the subsurface could be predicted, corresponding well with the observed results. Final failure life prediction based on the damage mechanics concept was found to be applicable, by considering both the final failure surface connecting the weakest grain boundaries and the effective stress against this surface. The fracture mechanics approach was also found applicable when assuming the initial crack length from the high peaks of the simulated small defects in the last stage of creep life.  相似文献   
49.
Cong  Peihong  Igari  Takashi  Mori  Shigeyuki 《Tribology Letters》2001,9(3-4):175-179
Monolayers of long-chain carboxylic acids, with various fluorination ratios, were deposited on solid substrates to investigate the effects of surface properties on frictional behavior. It is found that a lower surface free energy correlates to a lower friction coefficient for the monolayers of partially fluorinated carboxylic acids. However, a stearic acid (C17H35COOH) monolayer shows the lowest friction coefficient, although its surface free energy is relative high. The two-dimensional elastic modulus, which might be used as a parameter to quantitatively characterize the film strength, was developed. Friction coefficients of the monolayers show a strong correlation with their elastic modulus, that is, the higher the elastic modulus, the lower the friction coefficient. The research results indicate that frictional properties of ultrathin films are mainly dependent on film strength. Enhancement of intermolecular attractive force might be a more effective way to improve the lubricating properties of ultrathin films.  相似文献   
50.
Updated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and several new entries since July 1996 are briefly described. © 1997 John Wiley & Sons, Ltd.  相似文献   
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