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101.
Up to now one of the main limitations for a large use of shape memory alloys (SMA)-based smart composite structures in the aerospace industry is the lack of useful numerical tools for design; in addition, some technological aspects still need a more detailed investigation. This article shows numerical modeling approaches adopted for the implementation of SMA constitutive laws in commercial codes such as ABAQUS. Two different approaches were selected. The first one is based on the thermomechanical model proposed by Turner and the other one follows the thermodynamic macromechanical constitutive law developed by Lagoudas. The implementation in ABAQUS code was followed by a procedure to evaluate model parameters and to experimentally validate the reliability of code predictions for specifically designed test situations. This article presents the test campaign carried out for the definition of these parameters and the numerical-experimental correlation for both the models.  相似文献   
102.
103.
A prospective single-blind study was conducted to compare flunitrazepam vs trazodone in the premedication of patients undergoing day-case surgery for termination of pregnancy, with particular regard to the degree of preoperative sedation, intraoperative analgesia and postoperative recovery. 86 patients were randomly allocated to receive orally 45 minutes before the surgical procedure either flunitrazepam 2 mg (group F) or trazodone 50 mg (group T). In both groups anaesthesia was achieved by i.v. fentanyl 2.5 micrograms/kg and ketamina 250 micrograms/kg. Patients in group F showed a deeper degree of preoperative sedation. There were no significant differences in intraoperative analgesia and in the immediate arousal time. In the postoperative period, the incidences of emetic symptoms and dizziness were similar in both groups; the incidence of drowsiness was significantly higher in group F at 120 minutes but not at 180 minutes of observation. Psychomotor performance was assessed preoperatively two days before the surgical procedure and 60, 120 and 180 minutes after surgery, using the Toulouse-Pieron test and the reaction time to a luminous stimulus with the aid of a computerized analogic tachystoscope (Neurometer). Trazodone allowed a more rapid recovery of psychomotor performance and it can represent a valid alternative to the use of benzodiazepines in the premedication of day-case surgical patients.  相似文献   
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105.
The aim of this study is to provide a comprehensive characterization of stemness in pancreatic ductal adenocarcinoma (PDAC) cell lines. Seventeen cell lines were evaluated for the expression of cancer stem cell (CSC) markers. The two putative pancreatic CSC phenotypes were expressed heterogeneously ranging from 0 to 99.35% (median 3.46) for ESA+CD24+CD44+ and 0 to 1.94% (median 0.13) for CXCR4+CD133+. Cell lines were classified according to ESA+CD24+CD44+ expression as: Low-Stemness (LS; <5%, n = 9, median 0.31%); Medium-Stemness (MS; 6–20%, n = 4, median 12.4%); and High-Stemness (HS; >20%, n = 4, median 95.8%) cell lines. Higher degree of stemness was associated with in vivo tumorigenicity but not with in vitro growth kinetics, clonogenicity, and chemo-resistance. A wide characterization (chemokine receptors, factors involved in pancreatic organogenesis, markers of epithelial–mesenchymal transition, and secretome) revealed that the degree of stemness was associated with KRT19 and NKX2.2 mRNA expression, with CD49a and CA19.9/Tie2 protein expression, and with the secretion of VEGF, IL-7, IL-12p70, IL-6, CCL3, IL-10, and CXCL9. The expression of stem cell markers was also evaluated on primary tumor cells from 55 PDAC patients who underwent pancreatectomy with radical intent, revealing that CXCR4+/CD133+ and CD24+ cells, but not ESA+CD24+CD44+, are independent predictors of mortality.  相似文献   
106.
Preclinical data point to the contribution of transient receptor potential ankyrin 1 (TRPA1) channels to the complex mechanisms underlying migraine pain. TRPA1 channels are expressed in primary sensory neurons, as well as in glial cells, and they can be activated/sensitized by inflammatory mediators. The aim of this study was to investigate the relationship between TRPA1 channels and glial activation in the modulation of trigeminal hyperalgesia in preclinical models of migraine based on acute and chronic nitroglycerin challenges. Rats were treated with ADM_12 (TRPA1 antagonist) and then underwent an orofacial formalin test to assess trigeminal hyperalgesia. mRNA levels of pro- and anti-inflammatory cytokines, calcitonin gene-related peptide (CGRP) and glia cell activation were evaluated in the Medulla oblongata and in the trigeminal ganglia. In the nitroglycerin-treated rats, ADM_12 showed an antihyperalgesic effect in both acute and chronic models, and it counteracted the changes in CGRP and cytokine gene expression. In the acute nitroglycerin model, ADM_12 reduced nitroglycerin-induced increase in microglial and astroglial activation in trigeminal nucleus caudalis area. In the chronic model, we detected a nitroglycerin-induced activation of satellite glial cells in the trigeminal ganglia that was inhibited by ADM_12. These findings show that TRPA1 antagonism reverts experimentally induced hyperalgesia in acute and chronic models of migraine and prevents multiple changes in inflammatory pathways by modulating glial activation.  相似文献   
107.
In the past, a highly sensitive and efficient method was developed to map DNA replication origins in human cells, based on quantitative PCR performed on nascent DNA samples. This method allowed the identification of a replication origin in the myeloid HL-60 cell line, located on chromosome 19 within an approximately 500 bp segment near the lamin B2 gene [Giacca et al. (1994) Proc. Natl. Acad. Sci. USA, 91, 7119]. The same procedure has now been further simplified and extended to a variety of other exponentially growing human cells of different histological derivation (three neural, one connectival and one epithelial), with a nearly diploid chromosomal content. In all the six cell lines tested, the origin activity within the lamin B2 gene domain was localized to the same region. Furthermore, the lamin B2 origin was also found to be active in stimulated, but not in quiescent, peripheral blood lymphocytes.  相似文献   
108.
Bartter (BS) and Gitelman (GS) syndrome are autosomal recessive inherited tubulopathies, whose clinical diagnosis can be challenging, due to rarity and phenotypic overlap. Genotype–phenotype correlations have important implications in defining kidney and global outcomes. The aim of our study was to assess the diagnostic rate of whole-exome sequencing (WES) coupled with a bioinformatic analysis of copy number variations in a population of 63 patients with BS and GS from a single institution, and to explore genotype-phenotype correlations. We obtained a diagnostic yield of 86% (54/63 patients), allowing disease reclassification in about 14% of patients. Although some clinical and laboratory features were more commonly reported in patients with BS or GS, a significant overlap does exist, and age at onset, preterm birth, gestational age and nephro-calcinosis are frequently misleading. Finally, chronic kidney disease (CKD) occurs in about 30% of patients with BS or GS, suggesting that the long-term prognosis can be unfavorable. In our cohort the features associated with CKD were lower gestational age at birth and a molecular diagnosis of BS, especially BS type 1. The results of our study demonstrate that WES is useful in dealing with the phenotypic heterogeneity of these disorders, improving differential diagnosis and genotype-phenotype correlation.  相似文献   
109.
New advanced technologies have recently emerged as a potentially effective way for delivering stress management techniques. Specifically, the stress inoculation training (SIT) represents a validated approach to manage stress in several settings, and research is growing related to this clinical protocol combined with advanced technologies. This review aims to outline the state of the art of cyber-interventions based on SIT methodology (cyber-SIT). In the current review, we deeply analyzed and discussed three aspects of the selected studies: (1) the type of technological devices used for delivering cyber-SIT; (2) the sampling strategies; (3) and the stress-related measures for assessing the effectiveness of cyber-SIT. The results of this systematic review suggest the potential efficacy of cyber-SIT for managing psychological stress in several settings. Considering cyber-SIT for psychological stress, controlled trials testing a greater number of participants are needed. Other future challenges include adopting better inclusion/exclusion criteria, standardized outcome measures, and different conditions for comparing the effect and/or the integration of different technological devices. In conclusion, as the cyber-SIT may play an important role in the future clinical psychology, it is crucial to enhance the validation of this approach from a methodological point of view.  相似文献   
110.
Advances in information technology offer new opportunities for rehabilitation. In particular, the immersion capability provided by a synthetic environment could be exploited to design novel assistive devices. In virtual reality (VR), users navigate and interact with 3-D, computer-generated environments that are highly flexible and programmable, enabling the therapist to present a variety of controlled stimuli and to measure and monitor responses. VR provides a powerful means of increasing levels of environmental interaction in a highly controlled and structured manner. In this article, an overview is given of the design issues of a VR-enhanced orthopedic appliance used in rehabilitation of a person with spinal cord injury. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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