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1.
Journal of Applied Electrochemistry - Large area MoS2 ultra-thin film deposition is one of the big challenges in the recent years. Electrodeposition provides an opportunity to grow such ultra-thin...  相似文献   
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Charles R. (Bob) Schuster, an internationally recognized researcher on the psychopharmacology of drugs of abuse, passed away on February 21, 2011. Bob Schuster was a pioneer in the scientific study of addiction and one of the founders of a specialized research field called behavioral pharmacology. Bob mentored many young scientists, including 15 doctoral students, 9 postdoctoral fellows, and many visiting scientists from around the world, as well as junior faculty members at the academic institutions where he had faculty appointments. Bob was active in numerous professional organizations and was the recipient of many national and international awards. Personally, Bob Schuster touched the lives of a great many people: his students, colleagues, extended family, and many friends. Bob is survived by his wife and colleague Chris-Ellyn Johanson; four children, Lyzbett, Rebecca, Robert, and Alyson; and seven grandchildren. He is also survived by his sister Bette Quemore. He was a man of many talents, a loving husband and father, and a great friend. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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Recently, it has been shown at both the cellular and behavioral levels that ethanol has effects on the N-methyl-D-aspartate (NMDA) and gamma-aminobutyric acid (GABA)a receptor systems, leading to the possibility that the reinforcing effects of ethanol may be, at least partially, mediated via these receptor ionophores. In this study, a multiple schedule of ethanol and saccharin self-administration was used to study that possibility. Adult male Long-Evans rats were trained during 1-hr sessions to press on two different levers for 10% (w/v) ethanol and 0.1% (w/v) saccharin solutions, under an alternating 5-min, fixed-ratio-4 schedule of liquid availability. After training, tests were conducted with ethanol, NMDA antagonists and GABA agonists given before six consecutive sessions. Pretreatment with ethanol selectively decreased ethanol self-administration without altering saccharin self-administration. The competitive NMDA antagonist CPPene (D-3-(2-carboxypiperazine-4-yl)-1-propenyl-1-phosphonic acid [SDZ EAA 494]) and the noncompetitive NMDA antagonist phencyclidine decreased both ethanol and saccharin self-administration. The GABA agonists pentobarbital and diazepam also failed to reduce ethanol self-administration, relative to saccharin. Although these results do not support the hypothesis that antagonism of the NMDA receptor system or activation of the GABA receptor system can selectively modify ethanol-reinforced responding, they identify important issues for designing the best strategies to be used to assess selective drug effects on ethanol self-administration.  相似文献   
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One of the encoding methods offered by H.264 AVC is context-based adaptive variable length coding (CAVLC). This paper presents a high-throughput hardware implementation of the CAVLC encoder. A dual-coefficient scanning phase is investigated and modified to improve the speed of the encoding phase. This improved scanning solution determines all the required data for the encoding phase to be completed in a minimized and constant number of clock cycles. In addition, an algorithmic approach for encoding levels is exploited to reduce hardware resource requirements. The modified scanning phase approach offers significant throughput capabilities for CAVLC: at 200 MHz, the architecture is capable of encoding 1,080 p video files at 95 fps.  相似文献   
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delta 8-Tetrahydrocannabinol (delta 8-THC) is a naturally occurring cannabinoid with a characteristic pharmacological profile of in vivo effects. Previous studies have shown that modification of the structure of delta 8-THC by inclusion of a nitrogen-containing functional group alters this profile and may alkylate the cannabinoid receptor, similar to the manner in which beta-funaltrexamine (beta-FNA) alkylates the micro-opioid receptor. Two novel analogs of delta 8-THC were synthesized: a nitrogen mustard analog with a dimethylheptyl side chain (NM-delta 8-THC) and a cyano analog with a dimethylpentyl side chain (CY-delta 8-THC). Both analogs showed high affinity for brain cannabinoid receptors and when administered acutely, produced characteristic delta 9-THC-like effects in mice, including locomotor suppression, hypothermia, antinociception and catalepsy. CY-delta 8-THC shared discriminative stimulus effects with CP 55,940; for NM-delta 8-THC, these effects also occurred, but were delayed. Although both compounds attenuated the effects of delta 9-THC in the mouse behavioral tests, evaluation of potential antagonist effects of these compounds was complicated by the fact that two injections of delta 9-THC produced similar results, suggesting that acute tolerance or desensitization might account for the observations. NM-delta 8-THC, but not CY-delta 8-THC, attenuated the discriminative stimulus effects of CP 55,940 in rats several days following injection. Hence, addition of a nitrogen-containing functional group to a traditional cannabinoid structure does not eliminate agonist effects and may produce delayed attenuation of cannabinoid-induced pharmacological effects.  相似文献   
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Examined the effects of the D?/D? dopamine receptor antagonist α-flupenthixol in animal models designed to assess abuse-related behavioral effects of cocaine. Rhesus monkeys self-administered cocaine (17 or 33 μg/kg/injection, iv) during 1-hr daily sessions; periods of food-maintained behavior preceded and followed cocaine access. α-Flupenthixol (0.003–0.03 mg/kg, iv) increased self-administration rates, indicating an antagonism of cocaine's reinforcing effects but decreased rates of food-maintained responding. α-Flupenthixol (0.03 mg/kg) blocked the discriminative stimulus effects of cocaine (0.3 mg/kg) in squirrel monkeys but did not do so in rats trained to discriminate 10 mg/kg cocaine from saline. On the basis of available animal data and preliminary clinical trials, α-flupenthixol may warrant further study as a cocaine abuse pharmacotherapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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BACKGROUND: Although it is widely proposed that surgeons, before introducing a novel laparoscopic technique in man, should practice in an appropriate animal model for acquisition of the necessary technical skills, the effectiveness of those hands-on training courses are rarely documented. METHODS: In 1995 we have organized eight hands-on training courses for laparoscopic anterior interbody spine fusion in an in vivo porcine model. A total of 72 colleagues from 50 different centers of 12 countries participated, including orthopedic, trauma, visceral, neuro-, and vascular surgeons. Quality and effectiveness of the course were evaluated by a questionnaire after a 1.5- to 2.5-year period. RESULTS: During this time, 42.2% of the participating centers had applied the new technique successfully in man. Centers which participated in the course with a team that included a skilled laparoscopic surgeon and an orthopedic or trauma surgeon introduced the technique more frequently to clinical practice (57.9%) than those represented by only one participant (30. 8%). Moreover, there was a tendency toward a more frequent introduction of the technique to clinical practice in centers associated with university hospitals (57.1% vs. 29.2%), indicating the requirement of a particular infrastructure for this complex interdisciplinary procedure. Almost all participants (98.3%) agreed that for novel surgical techniques requiring advanced technical skills, there should first be training in a large animal model before the technique is applied in man. CONCLUSIONS: Complex laparoscopic procedures (i.e., laparoscopic spine surgery) can be successfully learned by in vivo hands-on training courses. We propose that for refinements and modifications of the technique (e.g. , the lumboscopic approach), there should also first be training in a large animal model before these are applied in man.  相似文献   
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Object based compression techniques are widely believed to have the potential to give the best compression results for a given signal quality. However, true object tracking and extraction are difficult and computationally expensive. In this paper, an arbitrarily shaped virtual-object compression method is developed. The method is similar to the object based compression methods in that it separates the changing portion of the video from the stationary portion, and encodes them independently. The changing portion of the video is grouped as a 3D arbitrarily shaped virtual-object whereas the unchanged portion of the video is grouped as background. The arbitrarily shaped virtual object is coded using 3D wavelet compression whereas stationary background is coded as a single frame using 2D wavelet compression. Experimental results demonstrate that the newly developed method has comparable performance with the state-of-the-art compression methods and significantly outperforms rectangular virtual-object compression.  相似文献   
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Data converter linearization has been a subject of some interest for most of the past decade. New methods of linearizing analog-to-digital converters (ADCs) continue to be developed. Various linearization methods are available but their comparative strengths and weaknesses are not easily recognizable, making it somewhat difficult to determine which compensator would provide maximum benefit for a specific device. This paper provides a novel performance comparison of two promising real-time linearization methods for flash ADCs: the in-device DEM method, and the peripherally-implemented BEET method using SFDR, SINAD, ENOB, and THD as performance metrics. It is found that BEET is the superior compensator for devices with INL values larger than 0.25 LSB and DNL values larger than 0.25 LSB for optimal SFDR. Results from SINAD, ENOB, and THD metrics indicate that BEET is superior compared to DEM for all devices that have INL>0.05 LSB.  相似文献   
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