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71.
72.
This study examined posttraumatic growth (PTG), positive change experienced as a result of the struggle with trauma, in children and adolescents exposed to a high-impact disaster, after which their experience of secondary adversity was minimal. The study also examined whether reduction in posttraumatic stress symptoms (PTSS) over time related to reports of PTG. There were 105 participants, age 6 to 17 years, who were directly exposed to the 2004 tsunami in Southeast Asia. They were interviewed 10 and 30 months after the disaster—PTSS was assessed at both time points, and PTG was assessed at 30 months. The individual's subjective reactions to the event and concurrent PTSS (30-months post-tsunami) were independently and positively related to PTG, whereas the decrease in PTSS was not related to growth. Children and youth in this study reported lower absolute levels of PTG than those in other studies. Taken in sum, findings suggest that secondary adversities may influence posttraumatic reactions and ongoing distress, which are hypothesized to play a key role in the development of PTG. In the absence of such secondary stressors, continued distress in the form of PTSS may serve to catalyze the growth process. Implications for clinical practice are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
73.
Tested the prediction that being more religious in one way—as an intrinsic end in itself—would be associated with displaying less racial prejudice when the prejudice was overt, but not when it was covert. It was also predicted that being more religious in another way—as an open-end quest—would be associated with displaying less racial prejudice even when the prejudice was covert. An attributional ambiguity technique developed by M. L. Snyder et al (see record 1981-05489-001) was used. 44 White undergraduates interested in religion chose between sitting with a Black person or a White person to watch a movie. In the overt prejudice condition, the same movie was being shown in both locations; in the covert prejudice condition, 2 movies were being shown. Although not all predicted relations were statistically reliable, the pattern of correlations was consistent with both predictions. An intrinsic orientation to religion was significantly negatively correlated with choosing to sit with the White person in the overt condition, but this correlation was close to zero in the covert condition. Only the quest orientation to religion was significantly negatively correlated with choosing to sit with the White person in the covert condition. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
74.
The need to model systems and their different aspects leads to research and development of models which support all views of a system. The growing complexity of the software imposes the use of architectures, not only because we want to build accurate systems, but also because we need to understand them. Separating aspects of different views usually helps us to manage software complexity. The current work is an analysis of two important approaches on architectural views and on the use of UML to reason about views. Our goal is to analyze the different aspects addressed by them and how UML is inserted on each of these models.  相似文献   
75.
The sensitivity to water vapour of one‐, two‐, and three‐layer epitaxial graphene (1, 2, and 3LG) is examined in this study. It is unambiguously shown that graphene's response to water, as measured by changes in work function and carrier density, is dependent on its thickness, with 1LG being the most sensitive to water adsorption and environmental concentration changes. This is furthermore substantiated by surface adhesion measurements, which bring evidence that 1LG is less hydrophobic than 2LG. Yet, surprisingly, it is found that other contaminants commonly present in ambient air have a greater impact on graphene response than water vapor alone. This study indicates that graphene sensor design and calibration to minimize or discriminate the effect of the ambient, in which it is intended to operate, are necessary to insure the desired sensitivity and reliability of sensors. The present work will aid in developing models for realistic graphene sensors and establishing protocols for molecular sensor design and development.  相似文献   
76.
In this study, a sterile and biocompatible chitosan (CHI) gel for wound healing applications was formulated. CHI powder was treated in autoclave (ttCHI) to prepare sterile formulations. The heat treatment modified the CHI molecular weight, as evidenced by GPC analysis, and its physical–chemical features. Differential scanning calorimetry studies indicated that the macromolecules, before and after thermal treatment, differ in the strength of water-polymer interaction leading to different viscoelastic and flow properties. Thermally treated CHI exhibited the following effects: (i) increased the proliferation and migration of human foreskin foetal fibroblasts at 24 h; (ii) accelerated wound healing (measured as area of lesion) at 3 and 10 days in an in vivo model of pressure ulcers. These effects were linked to the increase of the hydroxyproline and haemoglobin content as well as Wnt protein expression. Moreover, we found a reduction of myeloperoxidase activity and TNF-α mRNA expression. These observations suggest the potential of this novel CHI gel in wound healing and other therapeutic applications.  相似文献   
77.
Microtubule-targeting agents (MTAs) are effective drugs for cancer treatment. A novel diaryl [1,2]oxazole class of compounds binding the colchicine site was synthesized as cis-restricted-combretastatin-A-4-analogue and then chemically modified to have improved solubility and a wider therapeutic index as compared to vinca alkaloids and taxanes. On these bases, a new class of tricyclic compounds, containing the [1,2]oxazole ring and an isoindole moiety, has been synthetized, among which SIX2G emerged as improved MTA. Several findings highlighted the ability of some chemotherapeutics to induce immunogenic cell death (ICD), which is defined by the cell surface translocation of Calreticulin (CALR) via dissociation of the PP1/GADD34 complex. In this regard, we computationally predicted the ability of SIX2G to induce CALR exposure by interacting with the PP1 RVxF domain. We then assessed both the potential cytotoxic and immunogenic activity of SIX2G on in vitro models of multiple myeloma (MM), which is an incurable hematological malignancy characterized by an immunosuppressive milieu. We found that the treatment with SIX2G inhibited cell viability by inducing G2/M phase cell cycle arrest and apoptosis. Moreover, we observed the increase of hallmarks of ICD such as CALR exposure, ATP release and phospho-eIF2α protein level. Through co-culture experiments with immune cells, we demonstrated the increase of (i) CD86 maturation marker on dendritic cells, (ii) CD69 activation marker on cytotoxic T cells, and (iii) phagocytosis of tumor cells following treatment with SIX2G, confirming the onset of an immunogenic cascade. In conclusion, our findings provide a framework for further development of SIX2G as a new potential anti-MM agent.  相似文献   
78.
Whole body vibration (WBV) is well known to exert beneficial effects on multiple tissues, improving synaptic transmission, muscle mass, bone quality, and reducing anxiety and depressive behavior. However, the underlying molecular mechanisms are not yet fully understood, and organs and tissues may respond differently to the vibratory stimulus depending on multiple factors. Therefore, we investigated the WBV effects on the brain and musculoskeletal tissue of 4-month-old young mice, evaluating synaptic plasticity by electrophysiological recordings and tissue organization by histology and histomorphometric analysis. Specifically, WBV protocols were characterized by the same vibration frequency (45 Hz), but different in vibration exposure time (five series of 3 min for the B protocol and three series of 2 min and 30 s for the C protocol) and recovery time between two vibration sessions (1 min for the B protocol and 2 min and 30 s for the C protocol). In addition, immunohistochemistry was conducted to evaluate the expression of fibronectin type III domain-containing protein 5 (FNDC5), as well as that of tissue-specific markers, such as brain-derived neurotrophic factor (BDNF) in brain, myostatin in muscle and collagen I (COL-1) in bone. Our results suggest that the WBV effects depend closely on the type of protocol used and support the hypothesis that different organs or tissues have different susceptibility to vibration. Further studies will be needed to deepen our knowledge of physiological adaptations to vibration and develop customized WBV protocols to improve and preserve cognitive and motor functions.  相似文献   
79.
Background: Genetic risk scores (GRSs) have partially improved the understanding of the etiology of moderate hypertriglyceridemia (HTG), which until recently was mainly assessed by secondary predisposing causes. The main objective of this study was to assess whether this variability is due to the interaction between clinical variables and GRS. Methods: We analyzed 276 patients with suspected polygenic HTG. An unweighted GRS was developed with the following variants: c.724C > G (ZPR1 gene), c.56C > G (APOA5 gene), c.1337T > C (GCKR gene), g.19986711A > G (LPL gene), c.107 + 1647T > C (BAZ1B gene) and g.125478730A > T (TRIB gene). Interactions between the GRS and clinical variables (body mass index (BMI), diabetes mellitus, diet, physical activity, alcohol consumption, age and gender) were evaluated. Results: The GRS was associated with triglyceride (TG) concentrations. There was a significant interaction between BMI and GRS, with the intensity of the relationship between the number of alleles and the TG concentration being greater in individuals with a higher BMI. Conclusions: GRS is associated with plasma TG concentrations and is markedly influenced by BMI. This finding could improve the stratification of patients with a high genetic risk for HTG who could benefit from more intensive healthcare interventions.  相似文献   
80.
A relativistic temporal algebra for efficient design of distributed systems   总被引:1,自引:0,他引:1  
Adequate methods for checking the specification and design of distributed systems must allow for reasoning about asynchronous activities; efficient methods must perform the reasoning in polynomial time. This paper lays the groundwork for such an efficient deductive system by providing a very general temporal relation algebra that can be used by constraint propagation techniques to perform the required reasoning. Major choices exist when selecting an appropriate temporal model: discrete/dense, linear/nonlinear, and point/interval. James Allen and others have indicated the possible atomic relations between two intervals for the dense-linear-interval model, while Anger, Ladkin, and Rodriguez have shown those needed for a dense-branching-interval model. Rodriguez and Anger further developed a dense-relativistic-interval model based on Lamport'sprecede andcan affect arrows, determining a large number of atomic relations. This paper shows that those same atomic relations are exactly the correct ones for intervals in dense relativistic space-time if intervals are taken as pairs of points (E s ,E f ) in space-time such that it is possible to move fromE s toE f at less than the speed of light. The relations are defined and named consistently with the earlier work of Rodriguez and Anger, and the relationship between the two models is pursued. The relevance of the results to the verification of distributed specifications and algorithms is discussed.  相似文献   
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