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21.
Mesenchymal stem cells (MSCs) represent an attractive source within the field of tissue engineering. However, their harvesting often requires invasive medical procedures. Urine-derived stem cells (UDSCs) display similar properties to MSCs, and their obtention and further processing is non-invasive for the donors as well as low cost. Here, we offer a comprehensive analysis of their biological properties. The goal of this study was to analyze their morphology, stemness, differentiation potential and cytokine profile. We have successfully isolated UDSCs from 25 urine samples. First colonies emerged up to 9 days after the initial seeding. Cell doubling time was 45 ± 0.24 SD, and when seeded at the density of 100 cells/cm2, they formed 42 ± 6.5 SD colonies within 10 days. Morphological analyzes revealed that two different types of the cell populations have been present. The first type had a rice-grain shape and the second one was characterized by a polyhedral shape. In several cell cultures, dome-shaped cells were observed as well. All examined UDSCs expressed typical MSC-like surface markers, CD73, CD90 and CD105. Moreover, conditioned media from UDSCs were harvested, and cytokine profile has been evaluated showing a significantly higher secretory rate of IL-8, IL-6 and chemokines MCP-1 and GM-CSF. We have also successfully induced human UDSCs into chondrogenic, osteogenic and myogenic cell lineages. Our findings indicate that UDSCs might have immense potential in the regeneration of the damaged tissues.  相似文献   
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Objective: The therapeutic alliance has been linked to symptom change in numerous investigations. Although the alliance is commonly conceptualized as a multidimensional construct, few studies have examined its components separately. The current study explored which components of the alliance are most highly associated with depressive symptom change in cognitive therapy (CT). Method: Data were drawn from 2 published randomized, controlled clinical trials of CT for major depressive disorder (n = 105, mean age = 40 years, female = 62%, White = 82%). We examined the relations of 2 factor-analytically derived components of the Working Alliance Inventory (WAI; Horvath & Greenberg, 1986, 1989) with symptom change on the Beck Depression Inventory—II (BDI–II; Beck, Steer, & Brown, 1996) that occurred either prior to or subsequent to the examined sessions. WAI ratings were obtained at an early and a late session for each therapist–patient dyad. Results: Variation in symptom change subsequent to the early session was significantly related to the WAI factor that assesses therapist–patient agreement on the goals and tasks of therapy but not to a factor assessing the affective bond between therapist and patient. In contrast, both factors, when assessed in a late session, were significantly predicted by prior symptom change. Conclusions: These findings may reflect the importance, in CT, of therapist–patient agreement on the goals and tasks of therapy. In contrast, the bond between therapist and patient may be more of a consequence than a cause of symptom change in CT. The implications of these results and directions for future research are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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DNA methylation represents a crucial mechanism of epigenetic regulation in hematologic malignancies. The methylation process is controlled by specific DNA methyl transferases and other regulators, which are often affected by genetic alterations. Global hypomethylation and hypermethylation of tumor suppressor genes are associated with hematologic cancer development and progression. Several epi-drugs have been successfully implicated in the treatment of hematologic malignancies, including the hypomethylating agents (HMAs) decitabine and azacytidine. However, combinations with other treatment modalities and the discovery of new molecules are still the subject of research to increase sensitivity to anti-cancer therapies and improve patient outcomes. In this review, we summarized the main functions of DNA methylation regulators and genetic events leading to changes in methylation landscapes. We provide current knowledge about target genes with aberrant methylation levels in leukemias, myelodysplastic syndromes, and malignant lymphomas. Moreover, we provide an overview of the clinical trials, focused mainly on the combined therapy of HMAs with other treatments and its impact on adverse events, treatment efficacy, and survival rates among hematologic cancer patients. In the era of precision medicine, a transition from genes to their regulation opens up the possibility of an epigenetic-based approach as a diagnostic, prognostic, and therapeutic tool.  相似文献   
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We present a new set of interface techniques for visualizing and editing animation directly in a single three-dimensional scene. Motion is edited using direct-manipulation tools which satisfy high-level goals such as “reach this point at this time” or “go faster at this moment”. These tools can be applied over an arbitrary temporal range and maintain arbitrary degrees of spatial and temporal continuity. We separate spatial and temporal control of position by using two curves for each animated object: the motion path which describes the 3D spatial path along which an object travels, and the motion graph, a function describing the distance traveled along this curve over time. Our direct-manipulation tools are implemented using displacement functions, a straightforward and scalable technique for satisfying motion constraints by composition of the displacement function with the motion graph or motion path. This paper will focus on applying displacement functions to positional change. However, the techniques presented are applicable to the animation of orientation, color, or any other attribute that varies over time.  相似文献   
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This study followed treatment responders from a randomized controlled trial of adults with major depression. Patients treated with medication but withdrawn onto pill-placebo had more relapse through 1 year of follow-up compared to patients who received prior behavioral activation, prior cognitive therapy, or continued medication. Prior psychotherapy was also superior to medication withdrawal in the prevention of recurrence across the 2nd year of follow-up. Specific comparisons indicated that patients previously exposed to cognitive therapy were significantly less likely to relapse following treatment termination than patients withdrawn from medication, and patients previously exposed to behavioral activation did almost as well relative to patients withdrawn from medication, although the difference was not significantly different. Differences between behavioral activation and cognitive therapy were small in magnitude and not significantly different across the full 2-year follow-up, and each therapy was at least as efficacious as the continuation of medication. These findings suggest that behavioral activation may be nearly as enduring as cognitive therapy and that both psychotherapies are less expensive and longer lasting alternatives to medication in the treatment of depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Coexistence issues between IEEE 802.11b wireless communication networks and IEEE 802.15.4 wireless sensor networks, operating over the 2.4-GHz industrial, scientific, and medical band, are assessed. In particular, meaningful experiments that are performed through a suitable testbed are presented. Such experiments involve both the physical layer, through measurements of channel power and the SIR, and the network/transport layer, by means of packet loss ratio estimations. Different configurations of the testbed are considered; major characteristics, such as the packet rate, the packet size, the SIR, and the network topology, are varied. The purpose of this paper is to gain helpful information and hints to efficiently face coexistence problems between such networks and optimize their setup in some real-life conditions. Details concerning the testbed, the measurement procedure, and the performed experiments are provided.   相似文献   
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A linear array antenna design with desired radiation pattern has been presented based on genetic algorithm (GA) approach. Examples of cosecant and flat‐topped beam patterns are illustrated to show the flexibility of GA to solve complex antenna synthesis problems by suitably selecting the fitness function, even with a simple GA. The results have been validated by IE3D electromagnetic simulation. The antenna arrays with different element geometries can also be implemented using the proposed technique. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2008.  相似文献   
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