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71.
The explosive growth in access to the Internet suggests that the Internet may be a viable channel through which we can reach and treat the large population of smokers who are unlikely to use other modes of intervention. We applied national guidelines from the U.S. Public Health Service to assess the quality of interventions for smoking cessation that are available on the Internet. The Public Health Service guidelines were codified into two instruments to record and to rate quality of the intervention contents. Usability guidelines established by the National Cancer Institute were used to develop an instrument to assess Web site usability. Of the 202 Web sites identified in searches, 77% did not provide direct intervention over the Internet and were excluded from analyses. A total of 46 Web sites were included in our review. Usability assessments showed mixed results. Web sites were visually well organized and used consistent graphical design; however, reading difficulty averaged above the 8th-grade level. Over 80% of Web sites provided no coverage of one or more of the key components of tobacco treatment recommended in the guidelines. Ironically, areas receiving the least coverage were those most amenable to the interactive capabilities of the Internet, such as providing tailored, personalized advice to quit and arranging follow-up contact. Smokers seeking quality tobacco dependence treatment on the Internet may have difficulty distinguishing among the numerous Web sites available. Web sites that provide direct treatment often fail to fully implement treatment guidelines and do not take full advantage of the interactive and tailoring capabilities of the Internet.  相似文献   
72.
This article presents a study that examined the cardiovascular effects of a single session of repetitive cigarette smoking to investigate the possible development of short-term tolerance.  相似文献   
73.
Applied the model of the stages and processes (SPs) of change to exercise adoption and maintenance. Questionnaires dealing with the SPs of exercise change were developed and administered to 1,172 employees in a worksite health promotion project. Ss were split randomly into halves for (1) initial model development and testing and (2) confirmatory measurement model testing. Additional model confirmation was obtained by examining the hierarchical structure of the processes of change and by conducting stage and process analyses. Results suggest that the underlying constructs derived from smoking cessation and other addictive behaviors can be generalized to exercise behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
74.
Social learning theories suggest that conditioned responses may increase the risk for relapse. Responses to alcohol use cues (cue reactivity) are associated with variables suggestive of risk but little research exists on the relationship of cue reactivity to treatment outcome. Alcoholic men admitted for detoxification to a treatment program (n?=?45) underwent a cue reactivity assessment protocol, and 91% received 3-mo follow-up interviews. Greater salivary reactivity predicted greater frequency of drinking during follow-up. Attentional factors added independent variance to the prediction of drinking outcome, with greater attention to stimulus or to response predicting less drinking. Cue reactivity did not predict length of hospital stay or latency to first drink. Results are discussed in the context of information processing, social learning theories, and clinical implications for relapse prevention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
75.

Our earlier studies have shown that the electrostatic collection technique, a potentially "gentle" bioaerosol collection method, allows for efficient collection of airborne bacteria, but sensitive bacteria such as Pseudomonas fluorescens ( P. fluorescens ) lose their culturability during collection. We hypothesized that excessive stress was imposed on the sensitive bacteria by the sampler's conventional corona charging mechanism. In this research, we developed and built an experimental setup that allows us to analyze electrobiological properties of airborne microorganisms. In this experimental system, we imparted electric charges on airborne biological and nonbiological particles by aerosolizing them in the presence of an electric field. The charged P. fluorescens test bacteria and NaCl test particles were then channeled into a parallel plate mobility analyzer, which we have designed so that bacteria and inert particles carrying specific charge ranges can be extracted and made available for further analysis. When testing the experimental system, we related the extracted particle concentrations to the total particle concentration and obtained the charge distributions of these particles at different charging conditions. Our results have shown that even without charging, aerosolized P. fluorescens bacteria have a net negative charge and can carry up to 13,000 elementary charges per bacterium. In contrast, the NaCl particles were found to carry very few electric charges. We concluded that the electric charge carried by a bacterium consists of 2 components: its own natural charge, which can be high, and the charge imposed on it by the dispersion process. Our experiments have shown that the charge distributions on biological and nonbiological particles can be effectively manipulated by varying the external electric field during their aerosolization. Since airborne microorganisms may carry high internal electric charges, their collection by electrical field forces may be possible without first electrically charging them.  相似文献   
76.
Although early investigations were promising, no controlled follow-up studies have investigated the effectiveness of cue exposure treatment for alcoholics. In this study, inpatient alcoholics received either cue exposure integrated with urge coping skills training (CET; n?=?22) or a contrast condition (CC) involving daily contact with assessment only (n?=?18) in addition to standard treatment. Comprehensive assessment measures were used to investigate change in process and outcome variables. In the 2nd 3 mo after treatment, the CET group included more patients who were completely abstinent, had a higher percentage of abstinent days, and tended to report fewer drinks per day than did patients in the contrast condition. The significantly greater use of coping skills during follow-up by the CET group and the significant relationship of these coping skills to decreased drinking suggest that treatment effects were due, at least in part, to the coping skills training, consistent with recent formulations. Theoretical and treatment implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
77.
Although the effect of smoking cessation on weight gain is well-documented, little is known about the effect of weight loss on smoking. The association between saliva cotinine levels and weight loss was examined in a group of 9 obese female smokers during participation in a protein-sparing modified fast (Optifast). For the 1st 3 mo of treatment, Ss consumed only the protein-sparing supplement; for the next 3 mo, food was gradually reintroduced. Body mass index and saliva cotinine concentration were assessed at study entry and at 3 and 6 mo. A significant weight loss was noted at 3 and 6 mo, yet the cotinine level increased significantly over this time. It is unclear whether the cotinine increase is due to metabolic changes or an actual increase in nicotine intake. The results suggest that smoking-related health risks may increase during periods of significant weight loss. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
78.
Bupropion is an antidepressant shown to be efficacious for smoking cessation. This study examined the short- and long-term effects of bupropion (300 mg/day for 10 weeks) versus placebo on depression symptoms among 497 smokers attempting to quit in a randomized trial of bupropion plus behavioral counseling. Depression symptoms were assessed via the Center for Epidemiological Studies Depression Scale (L. Radloff, 1977) at baseline, end of treatment, and at 6-month follow-up. Baseline nicotine dependence level was assessed with the Fagerstrom Test for Nicotine Dependence (T. F. Heatherton, L. T. Kozlowski, R. C. Frecker, & K. O. Fagerstr?m, 1991). A regression model of depression symptoms demonstrated a significant interaction between nicotine dependence and treatment for the treatment phase and during follow-up. Depression symptoms did not mediate the effects of bupropion on abstinence at either time point. Highly nicotine-dependent smokers who receive bupropion are more likely to experience a decrease in depressive symptoms during active treatment but are also more likely to experience a rebound in depressive symptoms when bupropion is discontinued. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
79.
Increasingly more research is being directed towards the valorisation of waste materials as precursors for synthesising alkali-activated binders (AABs). For this study, varying blends of tungsten mining waste (TMW) and waste glass (WG) are activated using a combined sodium hydroxide (SH) and sodium silicate (SS) alkali solution. The activating solution itself is also varied with respect to the quantities of SS and SH to determine their effect on reactant formation and mechanical strength of TMW-based AABs. The results show that an increased WG content can effectively provide an additional source of reactive silica, contribute to the formation of (C, N)–A–S–H gel products and thus significantly improve the mechanical strength. High strength TMW–WG AABs were attributed to a faster TMW dissolution rate and dense microstructure. Such structures were characteristic of formulations with low alkali modulus (SiO2/Na2O < 2) combined with a SS/SH weight ratio of 2.8. For the latter, not only was a characteristic slower strength development with increasing alkali content observed, but there was also a limit of alkali metal concentration (Na2O ~ 3.1%) beyond which the strength deteriorated. Furthermore, SEM micrographs disclose that unreacted particles of WG reinforced the matrix by acting as a filler.  相似文献   
80.
Engineered nano–bio cellular interfaces driven by vertical nanostructured materials are set to spur transformative progress in modulating cellular processes and interrogations. In particular, the intracellular delivery—a core concept in fundamental and translational biomedical research—holds great promise for developing novel cell therapies based on gene modification. This study demonstrates the development of a mechanotransfection platform comprising vertically aligned silicon nanotube (VA-SiNT) arrays for ex vivo gene editing. The internal hollow structure of SiNTs allows effective loading of various biomolecule cargoes; and SiNTs mediate delivery of those cargoes into GPE86 mouse embryonic fibroblasts without compromising their viability. Focused ion beam scanning electron microscopy (FIB-SEM) and confocal microscopy results demonstrate localized membrane invaginations and accumulation of caveolin-1 at the cell–NT interface, suggesting the presence of endocytic pits. Small-molecule inhibition of endocytosis suggests that active endocytic process plays a role in the intracellular delivery of cargo from SiNTs. SiNT-mediated siRNA intracellular delivery shows the capacity to reduce expression levels of F-actin binding protein (Triobp) and alter the cellular morphology of GPE86. Finally, the successful delivery of Cas9 ribonucleoprotein (RNP) to specifically target mouse Hprt gene is achieved. This NT-enhanced molecular delivery platform has strong potential to support gene editing technologies.  相似文献   
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