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61.
Pavlovian conditioning models have influenced the development of cue exposure treatments for drug abuse. However, poor maintenance of extinction performance (renewal) after treatment is a common problem. A treatment-analogue experiment tested the role of context in renewal, as well as a potential strategy for reducing renewal. Seventy-eight social drinkers completed extinction trials to reduce saliva and urge reactivity to alcohol cues and were randomly assigned to a renewal test in either the same context as extinction, a different context, or the different context containing a cue from the extinction context (E-cue). As predicted, the different context produced greater renewal than the same context and renewal was attenuated when the E-cue was present. These results offer preliminary evidence for the context dependence of extinction to alcohol cues and for the use of an extinction cue to improve the generalizability of exposure therapies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
62.
The objective of this study was to develop an effective omeprazole buccal adhesive tablet with excellent bioadhesive force and good drug stability in human saliva. The omeprazole buccal adhesive tablets were prepared with various bioadhesive polymers, alkali materials, and croscarmellose sodium. Their physicochemical properties, such as bioadhesive force and drug stability in human saliva, were investigated. The release and bioavailability of omeprazole delivered by the buccal adhesive tablets were studied. As bioadhesive additives for the omeprazole tablet, a mixture of sodium alginate and hydroxypropylmethylcellulose (HPMC) was selected. The omeprazole tablets prepared with bioadhesive polymers alone had bioadhesive forces suitable for a buccal adhesive tablet, but the stability of omeprazole in human saliva was not satisfactory. Among alkali materials, only magnesium oxide could be an alkali stabilizer for omeprazole buccal adhesive tablets due to its strong waterproofing effect. Croscarmellose sodium enhanced the release of omeprazole from the tablets; however, it decreased the bioadhesive forces and stability of omeprazole tablets in human saliva. The tablet composed of omeprazole/sodium alginate/HPMC/magnesium oxide/croscarmellose sodium (20/24/6/50/10 mg) could be attached on the human cheek without disintegration, and it enhanced the stability of omeprazole in human saliva for at least 4 h and gave fast release of omeprazole. The plasma concentration of omeprazole in hamsters increased to a maximum of 370 ng/ml at 45 min after buccal administration and continuously maintained a high level of 146-366 ng/ml until 6 h. The buccal bioavailability of omeprazole in hamsters was 13.7% ± 3.2%. These results demonstrate that the omeprazole buccal adhesive tablet would be useful for delivery of an omeprazole that degrades very rapidly in acidic aqueous medium and undergoes hepatic first-pass metabolism after oral administration.  相似文献   
63.
In the last few years, many attempts have been carried out for the research of specific biological biomarkers in fibromyalgia (FM) since, so far, no laboratory tests have been appropriately validated for the diagnosis and the prognostic stratification of the disease. In our study for the first time, we carried out a proteomic analysis of the whole saliva of FM patients in order to evaluate salivary biomarkers. Twenty-two FM patients with all fulfilling the American College of Rheumathology diagnostic criteria for FM and 26 sex-and age-matched healthy subjects were enrolled in the study. Proteomic analysis was performed by combining 2-DE and MALDI-TOF-MS. The most relevant observation which emerged from the data analysis was the exclusive and significant over-expression of transaldolase and phosphoglycerate mutase I. These findings were validated by Western blot analysis and the total optical density confirmed the significant up-regulation of transaldolase and phosphoglycerate mutase I in FM samples with respect to healthy subjects. It was noteworthy that seven further salivary proteins resulted differentially expressed, namely: calgranulin A, calgranulin C, cyclophilin A, profilin 1, Rho GDP-dissociation inhibitor 2, proteasome subunit-α-type-2 and haptoglobin-related protein precursor. These preliminary results demonstrated the utility of salivary proteomic analysis in the identification of salivary biomarkers in FM patients and in clarifying some of the pathogenetic aspects of the disease.  相似文献   
64.
赵昱  霍李江 《包装工程》2020,41(21):131-137
目的 建立气相色谱-质谱法测定新型儿童餐具中23种初级芳香胺(Primary aromatic amines,简称PPAs)在模拟唾液中的迁移量的分析方法。方法 试样经模拟唾液振荡提取,二氯甲烷萃取后浓缩,甲醇定容后经气质联用仪分析,外标法定量。结果 该法在0.001~0.15 mg/dm2范围内具有良好的线性关系,相关系数(r)均大于0.998。方法的检出限为0.0001~0.0005 mg/dm2,加标回收率为85%~108%,相对标准偏差(RSD)为1.5%~8.7%,可满足测试要求。按照建立的方法,对10个实际样品进行测定,其中有9个样品检出了芳香胺。结论 该方法操作简便,灵敏度高,结果准确可靠,重现性好,贴近样品实际使用状态,能够满足新型儿童餐具中芳香胺迁移量的测定,并可为儿童餐具相关标准的制定及安全性评价提供数据支持和方法指导。  相似文献   
65.
以热塑性聚烯烃弹性体(TPE)和乙烯 醋酸乙烯酯共聚物(EVA)为基体树脂, 硫酸钡(BaSO4)、气相白炭黑(气相SiO2)和羟基磷灰石(HA)为无机填料, 制备了新型树脂根管充填材料(NRCFM), 着重对NRCFM 的组成进行了筛选与优化, 并对NRCFM在pH值为7.0和9.5的人工唾液介质中的稳定性进行了研究。实验结果表明, NRCFM的最佳组成为: TPE 30 g、EVA 5 g、BaSO445 g、 气相SiO2 10 g、 HA 10 g, 由此制备的NRCFM具有适宜的力学性能和优异的耐介质稳定性, 其邵氏A硬度88.9、 拉伸强度1.99 MPa、 断裂伸长率457%, 在pH值为7.0和9.5的人工唾液介质中浸泡30天后的质量变化小于0.5%。   相似文献   
66.
67.
PVC塑料中邻苯二甲酸酯类增塑剂在体液中的迁移行为研究   总被引:3,自引:0,他引:3  
利用新型溶胶-凝胶富勒烯涂层,采用顶空固相微萃取-气相色谱法对PVC塑料制品中的邻苯二甲酸酯类增塑剂在模拟体液(模拟人体汗液、模拟人体唾液)中的迁移行为进行了研究,对其固相微萃取条件和色谱分析条件进行了优化,并对PVC塑料制品在模拟体液中的浸泡条件进行了研究。该方法的最低检出限分别为0.082~0.730μg/L(模拟人体汗液)和0.079 1~1.370 0μg/L(模拟人体唾液),回收率为82%~107%,RSD<8%。  相似文献   
68.
An electrochemical study of corrosion of Tytin® dental amalgam was carried out in electrolytes similar to body fluids: artificial saliva with or without lactic acid, a polymer-containing product of the same composition as Glandosane® and in Krebs-Ringer solution. The electrochemical techniques of open circuit potential, polarisation curves, cyclic voltammetry and electrochemical impedance were employed as a function of immersion time to characterise the surface processes occurring and bring out the differences between the different solutions. The influence of pH was tested in solutions of artificial saliva with or without lactic acid. The results demonstrated the importance of the organic component on the rate of corrosion and of adsorption phenomena on the amalgam surface.  相似文献   
69.
Evaluation of ship handling mental workload/training has usually depended on professionals (captain, pilot) who have a lot of experience on board. We are attempting to evaluate a ship navigator's mental workload (stress) based on a physiological index. The physiological indices, heart rate variability (R-R interval) and nasal temperature, are good indices of the stress found in ship handling. It is best if we get response and evaluation results quickly on the spot. A recent study shows salivary amylase activity is induced by the sympathetic nervous system; however, a research on ship navigator has not yet accepted worldwide. This article proposes that salivary amylase activity shows a ship navigator's stress during ship handling. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
70.
In vivo aroma release during solid food consumption is a complex phenomenon that depends on food structure and composition, as well as on oral processing (combination of mastication and incorporation of saliva into the food product). The objective of this study was to understand and to predict the physico-chemical properties of aroma compounds through the dynamics of flavor release during in-mouth oral processing of food before bolus swallowing. Within this context, the evolution of two aroma compounds during bolus formation was explored by studying the two main properties that account for mass transfer: air/bolus partition and mass transfer coefficients. Four types of industrial cheese products (varying in fat and firmness) flavored with ethyl propanoate and 2-nonanone were chosen. Each matrix was mixed with various amounts of artificial saliva to mimic boluses at different stages of mastication. The air/bolus partition coefficient was determined by the static phase ratio variation method (PRV), while the mass transfer coefficient was obtained by non-linear regression from dynamic headspace experiments. Results showed that there is a dilution effect on the air/bolus partition coefficient and both a dilution and a product effect (firmness) on the mass transfer coefficient of ethyl propanoate in the bolus. These results were also validated with 2-nonanone for the low-fat cheeses.  相似文献   
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