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51.
BACKGROUND: Antimicrobial therapy is the recommended treatment for duodenal ulcer associated with Helicobacter pylori infection. The eradication of bismuth-based triple therapy with bismuth subcitrate, metronidazole and amoxicillin is limited by low compliance, drug resistance and side-effects. Two-week proton pump inhibitor (PPI)-based triple therapy has a higher eradication rate but is costly. This study was designed to compare the efficacy, patient compliance and cost of short-term PPI-based triple therapy with those of bismuth-based triple therapy. METHODS: Ninety patients with active duodenal ulcer disease and H pylori infection, proven with the 13C-urea breath test and CLO test (Campylobacter-like organism test) were treated randomly in three therapeutic groups: Group A, DeNol 120 mg, amoxicillin 500 mg and metronidazole 250 mg four times a day orally for 14 days; Group B, omeprazole 20 mg plus clarithromycin 500 mg twice a day and amoxicillin 500 mg four times a day for 14 days; Group C, omeprazole 20 mg, clarithromycin 250 mg and metronidazole 500 mg twice a day for seven days. Nizatidine 150 mg twice a day was given continuously following the end of anti-H pylori therapy for each group. Two months later, endoscopy, the CLO test and 13C-urea breath test were repeated to assess the eradication rate of H pylori and the ulcer-healing rate. Drug tolerance was evaluated by patients themselves by daily recording of any side-effects. RESULTS: Eighty-four patients completed the entire course of therapy and evaluation for H pylori infection. The H pylori eradication rates in Groups A, B and C were 75% (21/28), 93% (26/28) and 89% (25/28), respectively (p = 0.466). The ulcer healing rate was 86% (24/28) in Group A and 89% (25/28) in Groups B and C (p = 0.764). A total of 74 patients (88%) were free from symptoms at the end of the triple therapy. Symptom relief was faster in patients with PPI-based triple therapy (Groups B and C) (days 3 and 4) than for patients with bismuth-based triple therapy (day 5). The cost of Group C therapy was lower than that for Groups A and B. There were no major side-effects in any of the patients. CONCLUSIONS: One-week triple therapy with omeprazole, clarithromycin and metronidazole is highly effected for the eradication of H pylori. A therapeutic regime of one week's duration with lower cost, good compliance and mild side-effects may offer a good choice for treatment of duodenal ulcer associated with H pylori infection in clinical practice.  相似文献   
52.
Vascular nephropathies are a steadily increasing cause of end-stage renal failure. Arterionephrosclerosis and arteriolonephrosclerosis are common features in the hypertensive patient. This is especially true for blacks of African descent, in whom hypertension and nephrovasculopathies are a major cause of renal insufficiency. That primary hypertension leads to renal vascular lesions, glomerular obsolescence and interstitial fibrosis has long been established. It should not, however, obscure the fact that renal vascular lesions can be observed in animal models as well as in some humans, especially young blacks, in the absence of, or anticipating the onset of hypertension. This leads to considering the hypothesis that nephroangiosclerosis might stem from a genetic defect in the renal vascular bed and that this defect is strongly associated with the hypertensive trait. Atherosclerotic renal disease is a major, potentially treatable cause of chronic renal disease is a major, potentially treatable cause of chronic renal failure, especially in whites. It leads to renal atrophy, but the ischemic kidney retains a vigorous potential for tubular cell regeneration, which pleads for early recognition and treatment. Recent data suggest that renal ischemia, be it due to renal artery stenosis or to cholesterol crystal embolism, ranks among the multiple causes of secondary focal segmental glomerulosclerosis. Irrespective of its initial mechanism, ischemia induces renal fibrosis, the pathophysiology of which is centered on increased generation of angiotensin II. Finally, renal vascular lesions are commonly observed in the course of various nephropathies, even in the absence of hypertension, and the relationship between these lesions and the unfavorable prognosis of glomerulopathies, especially primary focal-segmental glomerulosclerosis, membranous glomerulopathy and IgA glomerulonephritis, remains to be elucidated. Expanding knowledge of the spectrum of nephrovasculopathies opens perspectives for investigating, understanding and treating a major mechanism of progressive renal insufficiency.  相似文献   
53.
One hundred and fifty-five strains of Aeromonas isolated in the stools of children under 5 years presenting with acute diarrheal disease were studied. Using the Aerokey II system for the identification of species, 47 strains were identified as Aeromonas caviae, 58 as Aeromonas hydrophila, 23 as Aeromonas veronii biovar sobria, 14 as Aeromonas trota, 9 as Aeromonas veronii biovar veronii, 2 as Aeromonas jandaei and 2 as Aeromonas shubertii, Emphasis is placed on the advantages of this method which allowed for the classification of new species not identified previously in our country.  相似文献   
54.
BACKGROUND AND OBJECTIVE: Drug resistance has become a major cause of treatment failure in patients with acute leukemia. P-glycoprotein (Pgp), which is associated with the multidrug resistance (MDR) phenotype, has been reported to be an important predictor of treatment outcome. The aim of this study was to analyze the value of Pgp expression in bone marrow or peripheral blood as a predictor of the response to remission induction chemotherapy as well as the duration of remission in patients with de novo acute myeloid leukemia (AML). DESIGN AND METHODS: We examined the expression of Pgp in 82 patients with de novo AML using an immunocytochemical assay with the C219 monoclonal antibody. RESULTS: Twenty-seven of the 82 patients (33%) were C219-positive in from 1% to 100% of their cells. Thirteen cases (16%) showed a positive reaction in more than 50% of the leukemic cells. Only hyperleukocytosis was significantly associated with higher expression of Pgp. Although 8 of the 13 cases (62%) with more than 50% of cells having Pgp expression were CD34-positive, this association was not statistically significant. A univariate analysis of resistance to induction therapy showed a significantly higher resistance rate in patients with increased Pgp expression (P = 0.01) as well as in those patients with decreased reactivity to myeloperoxidase. The multivariate analysis revealed the independent prognostic value of Pgp expression. C219 reactivity did not have an influence on remission duration. INTERPRETATION AND CONCLUSIONS: Our data indicate that P-glycoprotein expression is a reliable marker of resistance to induction treatment in patients with de novo AML.  相似文献   
55.
56.
The effect of the output power and output spectral distribution of the radiation energy fed to a photoreactor upon the reaction yield and selectivities is studied both theoretically and experimentally. The study aims at the analysis of these influences in a series reaction such as the photochlorination of methane where methylene chloride and eventually chloroform are the most valuable products. The computational model employed has been verified for a group of selected conditions by means of bench-sale experiments.

It is found that the chlorine conversion shows the expected square root dependence with respect to the Local Volumetric Rate of Energy Absorption (LVREA). This dependence, in a first approximation, can also be assigned to the effect of the radiation source output power upon yield. It is also found that by manipulating the amount of radiation power fed to the reactor it is possible to ascertain the operating conditions favoring the production of predetermined intermediate products (e.g., methylene chloride or chloroform).

It is concluded that the use of customized lamps especially designed for each particular product on the basis of feasible changes in the characteristics of the existing radiation sources will favor a selective and more economical production of some of the stable intermediates, i.e., lamp design is an important feature in any optimal process design.  相似文献   
57.
Although it is known that crops can directly emit N2O, their contribution to the total N2O emission from crop-soil systems under field conditions is not well understood. This study was conducted to study the contribution of crops to total N2O emission from soybean-soil and maize-soil systems in northeastern China. The effects of N fertilization on N2O emission and NO 3 -N concentration in plants were also studied. The emission from crop-soil systems was measured with the closed chamber method, whereas the direct emission from crops was measured with the soil surface-sealed method. The addition of fertilizer N significantly increased the NO 3 -N concentration in crops and enhanced the N2O emission from crop-soil systems and from crops alone. The amount of N2O emitted directly from soybean plants accounted for 6 to 11% of the total soybean-soil emission. Similarly, the amount of N2O emitted directly from maize plants accounted for 8.5 to 16% of the total maize-soil emission. The proportion of the applied N lost through direct N2O emission from plants ranged from 0.19 to 0.34%, whereas the proportion of the applied N lost through N2O emission from the crop-soil system ranged from 1.1 to1.9%. These results suggest that the use of chambers that do not include plants may lead to an underestimation of the total N2O emission from crop-soil systems. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
58.
Disposal of urban, agricultural and industrial organic residues impliesan increasing problem because of all the economic and environmentalrepercussions involved. One of the most adequate ways of managing this problemis the agricultural use of these wastes as organic amendments. Three organicresidues (AC, olive mill waste water sludge compost; MWC, municipal solid wastecompost; and PS, paper mill sludge) were used in a 3-year field experimentinvolving orange production. The effect of their application on crop productionand on soil quality was investigated. Soil samples (0–20 cm depth)collected 11 months after the last soil amendment were analysed for: pH and EC,Kjeldahl-N, available-P, available-K, total organic carbon, humic substances,dehydrogenase, phosphatase, -glucosidase, urease andbenzoyl-argininamidehydrolysing protease (BAA-protease) activities. Generally, the application of the MWC and PSincreased orange yield when compared to control. Moreover, total organic carbonand humic substances significantly increased in soils treated with all theorganic amendments. Organic fertilisation increased the Kjeldahl-N andavailable-P contents of the soil. The application of the organic residues also causedsignificant increases in dehydrogenase, -glucosidase, urease andBAA-protease activities of the soil. Significant positive correlations (p <0.01) between these enzymatic activities and total organic carbon were foundforall treatments. Significant positive correlation between dehydrogenase, urease,-glucosidase, and BAA-protease and orange yield was also found. However,a clear inhibition of phosphatase activity was observed in soils treated withPS. The results indicate that the repeated application to the soil of moderateamounts of organic amendments has positive effects on the chemical andbiochemical properties of the soil, as well as on the orange yield.  相似文献   
59.
The N mineralized from soil organic matter provides an important portion of N available for crop production. The objective of this study was to determine the amount of spatial variability in N mineralization potential in a field and to evaluate three different methods that might be used to estimate this variability. The three methods tested included predicting the N mineralized from surface soil properties as well as from a biological and a chemical procedure. Three soils varying in N mineralization potential were selected for the study from a field in the Georgia Coastal Plain. The N mineralized from these soils was determined by an N balance of unfertilized and cropped plots. The amount of N mineralized could not be reliably predicted from surface soil organic C, although surface soil clay concentration was positively correlated with the N mineralized. The N mineralized that was predicted using mineralization parameters determined by aerobic incubation, adjusted daily for soil water content and temperature, was approximately 50% of the field measurements of N mineralized. The values of NH4-N extracted with hot 2 M KCl were related significantly to N mineralized in the field (r2= 0.60) and also to the zero order rate constant of mineralization, k0 (r2= 0.77), determined from the N mineralized in the aerobic laboratory incubation.  相似文献   
60.
Five candidate pheromone components were identified by analyzing pheromone gland extracts by gas chromatography (GC), coupled GC-electroantennographic detection (EAD), and coupled GC-mass spectrometry (MS): (E)-11-hexadecenol(E11–16 : OH), (Z)-11-hexadecenol (Z11–16 : OH),(E)-11-hexadecenal, (E)-11-hexadecenyl acetate, and (Z)-3,(Z)-6,(Z)-9-tricosatriene (Z3,Z6,Z9–23 : Hy). In electroantennogram (EAG) recordings, synthetic E11–16 : OH elicited stronger antennal responses at low doses than other candidate pheromone components. Field tests demonstrated that synthetic E11–16 : OH as a trap bait was effective in attracting males, whereas addition of Z11–16 : OH inhibited the males' response. Z3,Z6,Z9–23 : Hy strongly enhanced attractiveness of E11–16 : OH, but was not attractive by itself. A pheromone blend with synergistic behavioral activity of an alcohol (E11–16 : OH) and hydrocarbon (Z3,Z6,Z9–23 : Hy) component is most unusual in the Lepidoptera. The synthetic two-component pheromone is approximately 60 times more attractive than the female-produced blend and might facilitate the control of this pest.  相似文献   
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