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Surveillance cultures for vancomycin-resistant enterococci (VRE) are time-consuming and expensive for the laboratory to perform. Therefore, we investigated the use of PCR as an alternative method of detecting and identifying VRE directly in fecal samples. PCR primers directed to vanA, vanB, vanC1, vanC2, and enterococcal ligase genes were used to detect and identify VRE in fecal material obtained by rectal or perirectal swabbing. Although PCR-inhibitory substances were present in DNA prepared directly from the swabs, the inhibitory substances could be reduced by processing the nucleic acid with two commercially available DNA preparation columns. Fecal material from 333 swabs was cultured on several selective agar media before and after broth enrichment. DNA was extracted from the fecal material and was analyzed by PCR. By using all four primer sets, only 59 (67.8%) of the samples were positive for vanA. However, after retesting the negative samples with only the vanA primer set, 77 (88.5%) of 87 specimens that were culture positive for Enterococcus faecium containing vanA were positive by PCR. One specimen was PCR positive for the vanA gene but culture negative for enterococci. The specificity of the vanA assay was 99.6%. PCR analysis of enrichment broth samples with all four primers sets after 15 to 18 h of incubation detected 74 (85.1%) of the 87 culture-positive specimens. The specificity of the vanA assay after the enrichment step was 100%. No vanB-containing enterococci were recovered by culture. Since 16 samples can be tested by PCR in 4 h (including electrophoresis), identification of VRE is possible within 8 h of specimen submission at a cost of approximately $10.12/assay. Thus, PCR may be a cost-effective alternative to culture for surveillance of VRE in some hospitals.  相似文献   
73.
BACKGROUND: The diffuse nature of cardiac allograft vasculopathy makes early detection of the disease by traditional noninvasive methods or coronary angiography difficult. The aim of this study was to determine if there is a relation between abnormalities in vessel wall morphology, as assessed by intracoronary ultrasound, and a decreased vasodilatory response to the endothelium-dependent vasodilator papaverine hydrochloride and if cardiac allograft vasculopathy detected by coronary angiography is associated with specific intracoronary ultrasound findings. METHODS AND RESULTS: Twenty-three heart transplant recipients underwent 25 intracoronary ultrasound studies and 24 studies of coronary vasomotor tone 10 days to 8.3 years after surgery using a 20-mHz intracoronary ultrasound catheter. The studies were divided in two groups according to the presence (n = 7, group 1) or absence (n = 18, group 2) of angiographically evident cardiac allograft vasculopathy. Qualitative assessment of vessel wall morphology and quantitative analysis of the vasodilator response to the injection of papaverine hydrochloride into the coronary artery distal to the imaging site were performed off-line, and results for the two study groups were compared. A significantly higher percentage of patients with than without angiographic evidence of cardiac allograft vasculopathy had a three-interface vessel wall morphology by intracoronary ultrasound (100% versus 11%, P < .001). In two recipients who underwent two serial studies, the appearance of three interfaces in the vessel wall or a progressive thickening of the inner interface of the vessel wall occurred in conjunction with the appearance of angiographic cardiac allograft vasculopathy. The vasodilator response to papaverine was less in patients with than in those without angiographically evident cardiac allograft vasculopathy both in terms of absolute and relative increases in lumen diameter (+0.1 +/- 0.12 mm versus +0.3 +/- 0.17 mm, P < .05, and +5.1 +/- 5.3% versus +8.2 +/- 5.3%, P = NS) and lumen cross-sectional area (+0.5 +/- 0.6 mm2 versus +1.7 +/- 1.1 mm2, P < .02, and +7.1 +/- 8.8% versus 16.6 +/- 11.0%, P = .055), respectively. CONCLUSIONS: Intracoronary ultrasound assessment of vessel wall morphology and evaluation of vascular response to endothelium-dependent vasodilators are useful techniques for detecting cardiac allograft vasculopathy.  相似文献   
74.
L1, NCAM and N-cadherin are cell adhesion molecules (CAMs), present on neuronal growth cones, which promote cell-contact dependent axonal growth by activating a second messenger pathway in neurons that requires calcium influx through L- and N-type calcium channels. In the present study we show that two of these CAMs, (L1 and N-cadherin) can stimulate neurite regeneration from axotomised adult dorsal root ganglion (DRG) neurons cultured in vitro and that this response can be fully inhibited by agents that block or negate the effect of calcium influx into the neurons. However although the response required calcium influx into neurons, it was not associated with an increase in the steady state levels of calcium in neuronal growth cones. These results suggest that small localised changes, or increases in the rate of calcium cycling, in growth cones and/or filopodia, are more important for regulating axonal growth than changes in the steady-state level of calcium.  相似文献   
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Hypodontia, congenitally missing teeth is more common in permanent than primary dentition. The present investigation reports the prevalence and pattern of hypodontia in the primary and permanent dentitions, excluding third molars in a sample of Saudi children. The sample consists of 1,300 children, aged 5 to 10 years of age. Clinical and radiographic examinations were performed. The prevalence of children with hypodontia was found to be 2.6 percent. The mandibular second premolar was the tooth most frequently absent and account for 45 percent of the total missing teeth. In primary dentition, the maxillary lateral incisor was the tooth most frequently absent (9%). A peg-shaped permanent maxillary lateral incisor was present in 0.7 percent of the sample. Congenitally missing teeth were almost equally distributed between maxillary (52%) and mandibular (48%) arches.  相似文献   
78.
This study carried out in Hong Kong, identified 29 Chinese patients' perceptions of the importance of nursing care behaviours in an acute setting using a Chinese language translated version of the CARE-Q instrument. Patients ranked items concerned with 'giving the patients' treatments and medication on time' as the most important and 'sits down with the patient' as the least important. Comparisons are made with the results from other cultures and specific Chinese cultural interpretations are drawn to provide direction for nursing care of Chinese patients in Hong Kong and worldwide.  相似文献   
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BACKGROUND: No effective treatment exists in the United States for acute attacks of hereditary angioedema (HAE). STUDY DESIGN AND METHODS: To evaluate the efficacy and safety of C1 inhibitor concentrate in treating HAE, a large primary care and referral center hospital conducted a randomized, placebo-controlled, double-blind trial with intent-to-treat analysis. Of the 36 patients enrolled in the study, 23 received treatment, and 22 completed the trial. C1 inhibitor concentrate or albumin (placebo) infusions were administered in a blind fashion to HAE patients who came to the hospital for treatment no later than 5 hours after an attack began. RESULTS: Relief was almost twice as fast in persons receiving C1 inhibitor concentrate than in the controls: 7.62 hours (mean; SD 7.08) versus 15.35 hours (mean; SD 8.31), respectively. The difference for time-to-relief was highly significant (p = 0.007, Mann-Whitney U test). The median time-to-relief was 6.17 hours (interquartile range 0.33-15.35) in the treatment group and 15.35 hours (interquartile range 14.00-22.83) in the control group. Resolution of symptoms was one-third faster in the C1 inhibitor concentrate group than in the placebo group: 23.98 hours (mean; SD 14.81) and 34.58 hours (mean; SD 13.56), respectively (p = 0.09, Mann-Whitney U test). Recovery of functional C1 inhibitor was 119.65 percent (mean; SD 50.80), and half-life was 37.87 hours (mean; SD 19.75). Recovery of antigenic C1 inhibitor was 147.75 percent (mean; SD 97.68), and half-life was 24.01 hours (mean; SD 9.70). There were no viral infections or serious adverse effects from the drug after 70 attacks in the treatment group and 96 attacks in the control group. CONCLUSIONS: C1 inhibitor concentrate is a safe, effective treatment for acute attacks of HAE.  相似文献   
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