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11.
Alcohol and tobacco use covary at multiple levels of analysis, and co-use of the 2 substances may have profound health consequences. To characterize the motivationally relevant processes contributing to co-use, the current study used ecological momentary assessment (EMA) to examine the subjective consequences of naturally occurring simultaneous use of alcohol and tobacco. Current smokers who reported frequently drinking alcohol (N = 259) used electronic diaries to monitor their daily experiences for 21 days. Participants responded to prompted assessments and also initiated recordings when they smoked a cigarette or completed the first drink in a drinking episode. Momentary reports of smoking and alcohol consumption were associated with one another, and these effects remained after adjustment for occasion- and person-level covariates. When participants consumed alcohol, they reported increased pleasure and decreased punishment from the last cigarette. Smoking was associated with small increases in pleasure from the last drink. Ratings of buzzed and dizzy were synergistically affected by co-use of alcohol and tobacco. Co-use was also followed by higher levels of craving for both alcohol and tobacco. Results point to the importance of reward and incentive processes in ongoing drug use and suggest that alcohol intensifies real-time reports of the motivational consequences of smoking more strongly than smoking affects corresponding appraisals of alcohol effects. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
12.
Biocompatible polymeric scaffolds were fabricated by mixing 5 wt.% poly(ε-caprolactone) (P) with 4 wt.% gelatin (G) and 1.6 wt.% Dulbecco's modified Eagle's medium containing 10% fetal bovine serum (D). These PGD scaffolds were also treated with atmospheric pressure (AP) plasma using O2 reactive gas (to create O-PGD scaffolds). The physicochemical and mechanical properties of the PGD scaffolds were characterized by in vitro biodegradability tests, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, contact angle measurements, and tensile strength measurements. The wettability and hydrophilic properties of the scaffold surface were improved remarkably by adding G and D to P, and by subsequent oxygen-assisted AP plasma treatment. An MTT assay, a cell attachment efficiency assay, scanning electron microscopy, and confocal microscopy revealed that Chinese Hamster Ovary (CHO)-K1 cells exhibited higher cell attachment and viability on the PGD and O-PGD scaffolds than on the P and PG scaffolds. Furthermore, the long-term viability of the CHO cells on the PGD and O-PGD scaffolds without exchanging the cell culture media was significantly improved compared to their viability on the P and PG scaffolds. Overall, the PGD and O-PGD scaffolds are expected to be useful as cell growth supporting biomaterials in tissue engineering.  相似文献   
13.
Ecological momentary assessment (EMA; Stone & Shiffman, 1994) was used to characterize and quantify a dynamic process--affective instability in borderline personality disorder (BPD). Sixty outpatients (34 with BPD and affective instability; 26 with current depressive disorder but not with BPD or affective instability) carried electronic diaries for approximately 1 month and were randomly prompted to rate their mood state up to 6 times a day. Results indicated that BPD patients (a) did not report significantly different mean levels of positive or negative affect; (b) displayed significantly more variability over time in their positive and negative affect scores; (c) demonstrated significantly more instability on successive scores (i.e., large changes) for hostility, fear, and sadness than did patients with depressive disorders; and (d) were more likely to report extreme changes across successive occasions (≥90th percentile of change scores across participants) for hostility scores. Results illustrate different analytic approaches to quantifying variability and instability of affect based on intensive longitudinal data. Further, results suggest the promise of electronic diaries for collecting data from individuals in their natural environment for purposes of clinical research and assessment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
14.
Traditional self-report measures of psychopathology may be influenced by a variety of recall biases. Ecological momentary assessment (EMA) reduces these biases by assessing individuals’ experiences as they occur in their natural environments. This study examines the discrepancy between trait questionnaire, retrospective report, and EMA measures of affective instability in psychiatric outpatients either with a borderline personality diagnosis (n = 58) or with a current episode of major depressive disorder or dysthymia (n = 42). The authors examined the agreement of 3 trait measures of affective instability—the Affective Instability subscale of the Personality Assessment Inventory–Borderline Features scale (L. C. Morey, 1991), the Affect Intensity Measure (R. J. Larsen, E. Diener, & R. Emmons, 1986), and the Affect Lability Scales (P. D. Harvey, B. R. Greenberg, & M. R. Serper, 1989)—and 1 retrospective mood recall task with EMA indices of mood and mood instability. Results indicate only modest to moderate agreement between momentary and questionnaire assessments of trait affective instability; agreement between recalled mood changes and EMA indices was poor. Implications for clinical research and practice and possible applications of EMA methodology are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
15.
A variety of information and communication media have been employed to support the interaction of consumers with products and sales representatives in electronic-commerce (EC). But, the question of what impact those media have on consumers in EC has not been sufficiently addressed in the literature. The objective of this study is to investigate the effect of the richness of consumers’ interaction with products and with sales representatives on changes in their attitude towards and their intention to use business-to-consumer (B2C) EC. Controlled lab experiments were conducted using two types of products and multiple levels of interaction richness. The results show that interaction richness has positive impact on consumers’ attitude towards B2C EC. Additionally, the study finds that the impact is stronger in the case of purchasing a high-complexity product than a low-complexity product, and that consumers’ attitude change is positively related with their intention to use B2C EC. Differential effects on two facets of attitude, ease of use in accomplishing the tasks and usefulness were observed leading to interesting implications and future research directions.  相似文献   
16.
Although there has been a pickup in the growth of business-to-consumer electronic commerce (EC) recently, the overall growth appears to have failed to live up to the various forecasts. Notwithstanding the concerns of security and privacy, this paper posits that for complex products and services offered on the web, existing EC interfaces (ECIs) lack the necessary "richness" to overcome the virtual nature that consumers face compared with a physical store. We empirically validate a conceptual framework that exists in the literature to address these issues of ECI design by drawing on insights from contingency research in information system (IS) design and media choice behavior. This paper finds that a fit or congruence between the product type and the ECI richness (in product information representation, and product-related interaction and communication between the consumer and vendor) leads to superior outcomes. Specifically, buying a complex product (e.g., digital camera) on the Web requires a greater ECI richness in the form of experiencing higher social presence and/or higher product presence. On the other hand, a lean ECI is sufficient for a simple product (e.g., diskette). The role of tolerance for ambiguity (TA), which is an individual difference variable, in this relationship is also examined. A significant three-way fit of TA with ECI richness and product types on consumer behavior is found. A number of implications and future research extensions are discussed  相似文献   
17.
Tryptanthrin is an indoloquinazoline alkaloid isolated from indigo. Tryptanthrin and its benzo‐annulated derivative, benzo[b]tryptanthrin, inhibit both topoisomerases I (topo I) and II (topo II) and cause cytotoxicity in several human cancer cell lines. From diverse assessment methods, including cleavage complex stabilization, comet, DNA unwinding/intercalation, topo II ATPase inhibition, ATP competition for topo II, and wound‐healing assays, we determined that the mode of action of benzo[b]tryptanthrin is as a DNA non‐intercalative and ATP‐competitive topo I and II dual catalytic inhibitor. Benzo[b]tryptanthrin induced apoptosis through the cleavage of caspase‐3 and PARP in HCT15 colon cancer cells. Additionally, benzo[b]tryptanthrin reversed adriamycin resistance by down‐regulation of multidrug resistance protein 1 (MDR1) in adriamycin‐resistant MCF7 breast cancer cells (MCF7adr) with more potent inhibitory activity than tryptanthrin. Taken together, derivatization by benzo‐annulation of tryptanthrin ameliorated the MDR‐reversing effect of tryptanthrin and may pave the way to the discovery of a novel potent adjuvant agent for chemotherapy.  相似文献   
18.
BACKGROUND: Linoleic acid, which is a major derivative generated from hydrolysis of vegetable oils, is often found at high concentration in food processing and kitchen wastes. This fatty acid could be introduced into an anaerobic system treating piggery wastewater via co‐digestion strategy. In this study, the effect of CaCl2 on the inhibitory behavior of linoleic acid in the anaerobic digestion of piggery wastewater was investigated. RESULTS: Linoleic acid exerted strong inhibitory effects on methanization of piggery wastewater with IC50 of 376 mg L?1 and 568 mg L?1 for ISR (inoculum substrate ratio) 0.38 and 2.0, respectively. Among tested cations (Na+, Mg2+, Ca2+, Al3+ and Fe3+), only Ca2+ effectively reversed linoleic acid inhibition. In addition, it was found that CaCl2 restricted linoleic acid inhibition only when it was added before or immediately after linoleic acid addition. Without CaCl2, linoleic acid was stoichiometrically transformed to oleic acid, which persisted for a prolonged period. In the presence of CaCl2, however, linoleic acid was completely converted to methane without accumulation of oleic acid. It was also found that oleic acid was self‐inhibitory to its oxidation to acetate, and CaCl2 removed this inhibition. CONCLUSION: From these findings, it was concluded that calcium ion not only mitigated linoleic acid inhibition in the anaerobic digestion of piggery wastewater, but also enhanced its mineralization to methane. Copyright © 2010 Society of Chemical Industry  相似文献   
19.
Clinical and population-based samples show high comorbidity between Substance Use Disorders (SUDs) and Axis II Personality Disorders (PDs). However, Axis II disorders are frequently comorbid with each other, and existing research has generally failed to distinguish the extent to which SUD/PD comorbidity is general or specific with respect to both specific types of PDs and specific types of SUDs. We sought to determine whether ostensibly specific comorbid substance dependence-Axis II diagnoses (e.g., alcohol use dependence and borderline personality disorder) are reflective of more pervasive or general personality pathology or whether the comorbidity is specific to individual PDs. Face-to-face interview data from Wave 1 and Wave 2 of the National Epidemiologic Survey on Alcohol and Related Conditions were analyzed. Participants included 34,653 adults living in households in the United States. We used hierarchical factor models to statistically partition general and specific personality disorder dimensions while simultaneously testing for specific PD-substance dependence relations. Results indicated that substance dependence-Axis II comorbidity is characterized by general (pervasive) pathology and by Cluster B PD pathology over and above the relationship to the general PD factor. Further, these relations between PD factors and substance dependence diagnoses appeared to largely account for the comorbidity among substance dependence diagnoses in the younger but not older participants. Our findings suggest that a failure to consider the general PD factor, which we interpret as reflecting interpersonal dysfunction, can lead to potential mischaracterizations of the nature of certain PD and SUD comorbidities. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
20.

Object  

The objective of this study was to investigate effects of varying readout bandwidths on the arterial spin labeling (ASL)-perfusion MRI measurements at a high magnetic field MRI system.  相似文献   
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