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1.
While exercise training (ET) is an efficient strategy to manage obesity, it is recommended with a dietary plan to maximize the antiobesity functions owing to a compensational increase in energy intake. Capsiate is a notable bioactive compound for managing obesity owing to its capacity to increase energy expenditure. We aimed to examine whether the antiobesity effects of ET can be further enhanced by capsiate intake (CI) and determine its effects on resting energy expenditure and metabolic molecules. Mice were randomly divided into four groups (n = 8 per group) and fed high-fat diet. Mild-intensity treadmill ET was conducted five times/week; capsiate (10 mg/kg) was orally administered daily. After 8 weeks, resting metabolic rate and metabolic molecules were analyzed. ET with CI additively reduced the abdominal fat rate by 18% and solely upregulated beta-3-adrenoceptors in adipose tissue (p = 0.013) but did not affect the metabolic molecules in skeletal muscles. Surprisingly, CI without ET significantly increased the abdominal fat rate (p = 0.001) and reduced energy expenditure by 9%. Therefore, capsiate could be a candidate compound for maximizing the antiobesity effects of ET by upregulating beta-3-adrenoceptors in adipose tissue, but CI without ET may not be beneficial in managing obesity.  相似文献   
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The practical difficulty of parenteral application of fish vaccines against devastating fish diseases diverted the interest toward oral vaccination. Search for effective methods to enhance the oral uptake of viral and bacterial vaccines is continuing. The current research focus on a new role of mucosal fish vaccine adjuvants inducing the antigen uptake by enhancing vascularity or increasing intestinal permeability. Some inflammatory substances cause reversible pathology to the intestinal epithelium, which could be employed for the transepithelial passage of vaccine particles. The natural inflammatory substances used were capsaicin, piperine, and okadaic acid as 1 mg, 2 mg, and 1 μg/fish, respectively. Two inactivated vaccines were used as antigens to test the effect of these inflammatory substances in two different fish hosts. Tested vaccines were inactivated redspotted grouper nervous necrosis virus vaccine in sevenband grouper (Epinephelus septemfasciatus) and inactivated Edwardsiella tarda vaccine in red sea bream (Pagrus major) fish models. The inflammatory substances and each vaccine were anally intubated to fish. Capsaicin proved to be effectively aiding the transepithelial passage of vaccine particles more than piperine, while okadaic acid had no detectable effect.  相似文献   
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Polygodial, a terpenoid dialdehyde isolated from Polygonum hydropiper L., is a known agonist of the transient receptor potential vanilloid 1 (TRPV1). In this investigation a series of polygodial analogues were prepared and investigated for TRPV1‐agonist and anticancer activities. These experiments led to the identification of 9‐epipolygodial, which has antiproliferative potency significantly exceeding that of polygodial. 9‐Epipolygodial was found to maintain potency against apoptosis‐resistant cancer cells as well as those displaying the multidrug‐resistant (MDR) phenotype. In addition, the chemical feasibility for the previously proposed mechanism of action of polygodial, involving the formation of a Paal–Knorr pyrrole with a lysine residue on the target protein, was demonstrated by the synthesis of a stable polygodial pyrrole derivative. These studies reveal rich chemical and biological properties associated with polygodial and its direct derivatives. These compounds should inspire further work in this area aimed at the development of new pharmacological agents, or the exploration of novel mechanisms of covalent modification of biological molecules with natural products.  相似文献   
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张晓春  于良民  姜晓辉 《材料导报》2018,32(2):193-197, 202
以取代芳烃和N-羟甲基丙烯酰胺为原料,采用傅克烷基化反应合成了四种含辣素衍生结构单体:4-羟基-2-甲基-5-甲硫基苄基丙烯酰胺(A)、2-羟基-4-丙烯酰胺甲基-5-甲硫基-6-甲基苄基丙烯酰胺(B)、3-丙烯酰胺甲基-2-羟基苯甲酰胺(C)和1-丙烯酰胺甲基-2-萘酚(D),并通过红外光谱(IR)和核磁氢谱(1 H NMR)对其结构进行了表征。抑菌实验结果表明化合物D对两种受试菌(金黄色葡萄球菌和大肠杆菌)的抑制活性最高,最小抑菌浓度均可达到0.187 5mg/mL,且D对两种受试藻(三角褐指藻和新月菱形藻)的抑制活性也最高。以四种化合物为功能单体合成出树脂,树脂对受试藻均具有较高的抑制活性,含化合物D的树脂的抑制活性最高,72h后抑制率均可达到50%以上。  相似文献   
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In the absence of brain input, spinal systems can adapt to new environmental relations. For example, spinally transected rats given a legshock each time the leg is extended exhibit a progressive increase in flexion duration that minimizes net shock exposure, a simple form of instrumental learning. This capacity for learning is modulated by prior stimulation; both variable shock and inflammation produce a lasting inhibition of learning. An extended exposure to fixed spaced shock has no adverse effect on learning and opposes the consequences of variable shock. The present studies expand on these findings and demonstrate that fixed stimulation ameliorates the impact of peripheral inflammation. Spinally transected rats were administered 900 fixed spaced legshocks before (Experiment 1) or 1,800 legshocks after (Experiment 2) a subcutaneous hindpaw injection of capsaicin. Learning was assessed 24 hr later. Treatment with fixed shock attenuated the capsaicin-induced inhibition of learning. These findings suggest that fixed stimulation promotes adaptive plasticity and may foster recovery after injury. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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Production of capsaicin in free and immobilized placenta was compared in order to assess their capsaicin production ability. In immobilized placenta, maximum accumulation of capsaicin was on the 14th day of culture with a production of 2045 ug/culture, whereas in free placenta, the accumulation reached maximum on the 7th day (2050ug/culture). It was found that there was no significant difference between free and immobilized placenta in terms of capsaicin production, suggesting that immobilization is not necessary to enhance capsaicin accumulation in piacentai tissue. Pungency threshold of capsaicin produced in in vitro grown free piacentai tissues of Capsicum frutescens was done by Scoville heat units (SHU) method. Pungency analysis of capsaicin produced in free piacentai tissue showed that on day zero, pungency of tissue culture produced capsaicin (0.2267x105 SHU) was comparable to standard natural capsaicin (0.222×105 SHU), while on the 3rd day pungency of tissue culture produced capsaicin (0.3639×105 SHU) was slightly lower than standard natural capsaicin (0.4415×105 SHU).  相似文献   
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In this study, capsaicin microcapsules were prepared by the complex coacervation of gelatin, acacia, and tannins. The antimicrobial activities of these microcapsules on the common microorganisms of food preservation, Botrytis cinerea and Aspergillus niger, were investigated. The factors affecting their antimicrobial effects, including the microcapsule concentrations, pH values, and release behavior were also examined. The results showed that the optimum pH for the antimicrobial effect was about 5.0, which might be related to the strongest protein‐precipitating ability of tannins at this pH value. The inhibitory activity of the system originated from the synergistic actions of both capsaicin and tannins. The release behavior of the microcapsules had an important influence on the antimicrobial effect for the long shelf‐life storage of foods. The present study indicated that the capsaicin microcapsules displayed potential antimicrobial applications in the food storage. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1318–1321, 2006  相似文献   
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辣椒素的制备工艺及分析方法   总被引:39,自引:0,他引:39  
辣椒素作为辣椒中的生物活性成分,其制品在军事和医药上具有许多用途。对辣椒素的结构、性质及应用范围进行了介绍,分别论述了辣椒素的提取(即溶剂萃取法、超临界萃取法、微波法)和纯化方法(即溶剂萃取法、离子交换法、柱层析法、超临界CO2萃取法),进一步阐述了与之相配套的辣椒素的定性、定量分析方法,并对该领域的发展前景进行了展望。  相似文献   
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