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31.
Despite the serious and costly problems presented by juvenile sexual offenders, rigorous tests of promising interventions have rarely been conducted. This study presents a community-based effectiveness trial comparing multisystemic therapy (MST) adapted for juvenile sexual offenders with services that are typical of those provided to juvenile sexual offenders in the United States. Youth were randomized to MST (n = 67) or treatment as usual for juvenile sexual offenders (TAU-JSO; n = 60). Outcomes through 12 months postrecruitment were assessed for problem sexual behavior, delinquency, substance use, mental health functioning, and out-of-home placements. Relative to youth who received TAU-JSO, youth in the MST condition evidenced significant reductions in sexual behavior problems, delinquency, substance use, externalizing symptoms, and out-of-home placements. The findings suggest that family- and community-based interventions, especially those with an established evidence-base in treating adolescent antisocial behavior, hold considerable promise in meeting the clinical needs of juvenile sexual offenders. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
32.
RANTES and related molecules, constitute the C-C class of chemokine supergene family and a group of cytokines produced by hematopoietic cells constitute the MCP-1 or C-X-C class. The roles of most of these chemokines are not well known, although members of the C-X-C family are inflammatory agents. Here, we report that intradermal injection of RANTES 10 ng/50 microL subcutaneously in the abdominal skin produced a strong inflammatory reaction, as evidenced by Evans blue dye, greater than FMLP (10(-6) mol/L) (approximately 57%); while MCP-1, 10 ng/50 microL was less effective than FMLP (10(-6) mol/L) (approximately 54%). Moreover, the histologic analysis of the cells stained with Toluidine blue (0.1%) were analyzed at a magnification of x40). RANTES 10 ng/50 microL and LPS produced higher numbers (142 +/- 11 and 193 +/- 21 of cells/200 mm2, respectively) of basophilic cell accumulation in the skin injection sites compared with FMLP (10(-6) mol/L) (127 +/- 14/200 mm2), while MCP-1 10 ng/50 microL was less effective (88 +/- 10/200 mm2). Electron microscopy (x13,800) studies of skin injection sites revealed that RANTES was chemoattractant for mast cells. In a Northern blot analysis from homogeneous tissue biopsy from the intradermal injection sites, RANTES was more potent than MCP-1 in increasing histidine decarboxylase (HDC) mRNA, the sole enzyme responsible for the production of histamine from histidine. Since PGD2 is formed by mast cells on cell activation, we also studied the effect of RANTES and MCP-1 on PGD2 production in inflamed tissue in vivo. RANTES (20, 10, and 5 ng) and MCP-1 (20, 10, and 5 ng) strongly stimulated PGD2, in a dose-dependent manner, with a potency rank order of RANTES (10 ng/mL) approximately two times greater than MCP-1 (10 ng/mL).  相似文献   
33.
RNA synthesis in fully-grown mouse oocytes   总被引:1,自引:0,他引:1  
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34.
35.
Stress worsens certain disorders such as migraines or asthma, and has also been implicated in sudden myocardial arrest. It was previously shown that acute psychological stress by immobilization results in dura mast cell degranulation, an effect blocked by pretreatment with antiserum against corticotropin-releasing hormone (CRH). Moreover, CRH was recently shown to induce skin mast cell degranulation. The effect of psychological stress was investigated on rat cardiac mast cells, because their release of coronary constrictive and proinflammatory molecules contributes to myocardial ischemia and possibly arrhythmias. Immobilization of rats for 30 min induced maximal cardiac mast cell degranulation as evidenced by light and electron microscopy. This effect was inhibited by pretreatment with the "antiallergic" drug sodium cromoglycate (cromolyn), which is thought to act primarily through mast cell stabilization. Mast cell degranulation was also blocked by preincubation with antiserum against CRH and was partially inhibited by a CRH type-1 receptor selective antagonist. Sensory neuropeptides did not appear to influence this effect, but a nonpeptide neurotensin receptor antagonist blocked stress-induced cardiac mast cell degranulation. This finding supports the involvement of neuropeptide neurotensin which is present in the heart and is known to trigger mast cell degranulation. These results indicate acute stress could result in local CRH and nonpeptide neurotensin release which could contribute to myocardial pathophysiology through direct or indirect release of cardiac mast cell mediators.  相似文献   
36.
This paper presents the design process of a spherical robot capable of autonomous motion, and demonstrates how it can become a tool in child-development studies. The robot, named Roball, is capable of intentional self-propelled movements and can generate various interplay situations using motion, messages, sounds, illuminated parts and other sensors. Such capabilities allow Roball to interact with young children in simple and interesting ways, and to provide the potential of contributing to the development of their language, affective, motor, intellectual and social skills. Trials done with 12-24-month-old children demonstrate how Roball can be used to study children's interest in a self-propelled and intentional device. An experimental methodology to conduct such studies is presented: it is based on quantitative and qualitative techniques to evaluate interactions, thus enabling the identification of challenges and opportunities in child-robot interaction studies.  相似文献   
37.
A study on the extrusion of Eudragit E100 was carried out using supercritical carbon dioxide (scCO2) as plasticizer and foaming agent. ScCO2 modifies the rheological properties of the material in the barrel of the extruder and acts as a blowing agent during the relaxation when flowing through the die. For experiments, a single‐screw extruder was modified to be able to inject scCO2 within the extruded material. The aim is to determine a correlation between operating conditions and foam structure. The effect of three parameters was studied: the temperature in the die and in the metering zone, the screw speed, and the volumetric flow rate of CO2. An increase in temperature enhances the expansion rate and the average pore diameter and appears to be the most significant parameter. The effect of CO2 concentration is significant at small concentrations only: the higher the CO2 concentration, the lower the pore density and the higher both the pore diameter and the expansion rate. The effect of the screw speed is tricky because a variation of this speed involves a decrease of CO2 weight ratio. This study shows that the structure of the extrudates does not evolve with a coupling of screw speed increase and a subsequent CO2 weight ratio decrease. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   
38.
High‐temperature in situ synchrotron X‐ray powder diffraction experiments were carried out to investigate the phase transition mechanism of Zr2P2O9 (2ZrO2·P2O5 or “Z2P”). Linear thermal expansion coefficients were calculated for the low‐temperature phase (α‐Z2P) and the high‐temperature phase (β‐Z2P) from temperature‐dependent changes in lattice parameters. The crystal structures of α‐ and β‐Z2P were determined as a function of temperature by performing Rietveld crystal structure refinements. The structural changes at the phase transition are accompanied by an increase in the average atomic distance between neighboring Zr atoms. The occurrence of shorter metal–metal distances in α‐Z2P is interpreted to result from stronger interactions between partly occupied valence orbitals of the d0 metal atoms. The bond valence method was used to calculate the valence sums of the atoms of α‐ and β‐Z2P, respectively, considering also contributions resulting from covalently bonded atoms. As the bond strength between the metal atoms in Z2P decreases with the transition into the high‐temperature phase, notably, the metal–metal interactions are regarded to constitute a prerequisite for the stabilization of the α‐phase over the energetically favored β‐phase.  相似文献   
39.
Dust generation in solids handling involving free fall of bulk materials and impacts on a stockpile can cause many problems in industry and be a great danger for operators health. This paper describes an experimental set up to characterize the dust plume formed in free fall of powders from a hopper and investigates the influence of various outlet geometries on the dust plume. For this purpose an image analysis technique was developed to quantify the characteristics of the dust plume.  相似文献   
40.
Integrated intelligence experiments provide new opportunities for autonomous systems to assist humans in real-life situations. Using artificial emotions and human-robot communication, the authors designed an autonomous robot to attend AAAI. The robot must register itself at the conference as a student volunteer, perform various tasks, and give a presentation on its experiences at the conference. The authors report their experiences.  相似文献   
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