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1.
Excessive energy intake may evoke complex biochemical processes characterized by inflammation, oxidative stress, and impairment of mitochondrial function that represent the main factors underlying noncommunicable diseases. Because cow milk is widely used for human nutrition and in food industry processing, the nutritional quality of milk is of special interest with respect to human health. In our study, we analyzed milk produced by dairy cows fed a diet characterized by a high forage:concentrate ratio (high forage milk, HFM). In view of the low n-6:n-3 ratio and high content of conjugated linoleic acid of HFM, we studied the effects of this milk on lipid metabolism, inflammation, mitochondrial function, and oxidative stress in a rat model. To this end, we supplemented for 4 wk the diet of male Wistar rats with HFM and with an isocaloric amount (82 kJ, 22 mL/d) of milk obtained from cows fed a diet with low forage:concentrate ratio, and analyzed the metabolic parameters of the animals. Our results indicate that HFM may positively affect lipid metabolism, leptin:adiponectin ratio, inflammation, mitochondrial function, and oxidative stress, providing the first evidence of the beneficial effects of HFM on rat metabolism.  相似文献   
2.
Biotechnological synthesis of a new class of amphiphilic molecules—fatty hydroxamic acids—was carried out using the lipase ofMucor miehei by reacting hydroxyl amine with the fatty acids in their free or methyl ester form. Concurrently with enzymatic synthesis, chemical synthesis of hydroxamic fatty acids has also been developed by adapting methods that already existed for water-soluble acids. Different parameters were studied to determine the optimum operating conditions: temperature, molar ratio of reagents, quantity of biocatalyst and length of reaction. A general method, whatever the type of fatty acids used, is described.  相似文献   
3.
Dietary PUFA, mainly those of the n‐3 family, are known to play essential roles in the maintenance of energy balance and in the reduction of body fat deposition through the upregulation of mitochondrial uncoupling that is the main source of reactive oxygen species. We hypothesized that rat supplementation with raw donkey's milk (DM), characterized by low‐fat content and higher n3:n6 ratio, may affect energy balance, lipid metabolism, and prooxidant status as compared to animals treated with cow's milk. In the present study, the effects of drinking raw DM (for 4 weeks) on energy balance, lipid metabolism, antiinflammatory, and antioxidant/detoxifying defences was compared to that produced by rat intake of an iso‐energetic amount of raw cow's milk. The hypolipidemic effect produced by DM paralleled with the enhanced mitochondrial activity/proton leakage and with the increased activity or expression of mitochondrial markers namely, carnitine palmitoyl transferase and uncoupling protein 2. The association of decreased energy efficiency with reduced proinflammatory signs (TNF‐α and LPS levels) with the significant increase antioxidant (total thiols) and detoxifying enzyme activities (glutathione‐S‐transferase NADH quinone oxidoreductase) in DM‐treated animals, indicated that beneficial effects were attributable, at least in part, to the activation of nuclear factor 2 erythroid‐related factor 2 pathway.  相似文献   
4.
The study shows how the perceptions of opportunities for learning and personal development predict five dimensions of affective well-being (AWB: pleasure, comfort, placidity, enthusiasm, and vigor), and how this relationship is moderated by the perceptions of work-family conciliation. A sample comprising 404 individuals was collected. The findings show the following: (1) both the perceptions of opportunities for learning and personal development and perceptions of work-family conciliation predict AWB, the happier individuals being those who have high perceptions on both variables; (2) both variables interact in predicting AWB, in such a way that perceptions of high opportunities for learning and personal development may not lead to higher AWB if work-family conciliation is low. Post hoc analysis also suggests that the relationship between the perceptions of opportunities for learning and personal development and AWB tends to be nonlinear for individuals with perceptions of low work-family conciliation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
High levels of lipase activity are known to occur in Carica papaya latex, and this activity is being used in some biotechnological applications. The lipolytic activity of C. papaya lipase (CPL) on dietary triacylglycerols (TAG) has not yet been studied. Hence, the aim of this study was to characterise the specific activity of CPL on dietary TAG present in a crude preparation. Also, we have determined its stability during the lipolysis of a test meal at various pH values mimicking those occurring in the gastro-intestinal tract, with or without bile, and have compared these properties with those of porcine pancreatic extract (PPE) and human pancreatic lipase (HPL). CPL showed maximum stability at pH 6.0, both with and without bile. Some residual activity was still observed at pH 2 (20%), whereas the pancreatic lipases tested were immediately completely inactivated at this pH. In the absence of bile, the highest specific activities were measured at pH 6 in the case of CPL, PPE and HPL. Adding bile slightly decreased the CPL activity in the 4–6 pH range, thus shifting the optimum CPL activity to pH 7, where the presence of bile had no effect. Lipolysis levels decreased with the pH, but CPL was still more active than PPE at pH 5 on a relative basis. These results suggest that CPL might be a promising candidate for use as a therapeutic tool on patients with pancreatic exocrine insufficiency.  相似文献   
6.
Compassion is almost universally acknowledged as an important issue in the crisis management literature. The dominant perspective, however, approaches compassion instrumentally. The findings of this study on the compassionate support offered (or not) to employees during and after the Brisbane flood crisis of January 2011 provide insight into crisis management as a continuous process rather than a reactionary response when disaster arises. Three significant policy implications are generated: First, compassionate discourses and categorization schemas should be clearly articulated within the organization before crisis. Second, compassionate policies and practices need to be embedded in ongoing organizational routines and policies. Third, initiatives framed as compassion responses should not be assumed to necessarily create positive outcomes; rather, outcomes should be assessed on an ongoing basis.  相似文献   
7.
An appropriately designed controlled-release drug delivery system can be a major advance towarb solving problems concerning the targeting of a drug to a specific organ or tissue and controlling the rate of drug delivery to the target tissue. Hydrophilic matrices are an interesting option when developing an oral controlled-release formulation. The present study focuses on oral controlled-release dosage forms and the application of cellulose ether polymers in hydrophilic matrices. Key Words. Controlled-release matrices; Hydrophilic matrices; Cellulose ether polymers; Hydroxypropylmethylcellulose; HPMC  相似文献   
8.
Tretinoin, or retinoic acid, can be used in the treatment of a variety of skin diseases, depending on its concentration. Formulations containing tretinoin 1 % have been used in the therapy of malignant cutaneous diseases, namely, Kaposi 's syndrome. In lower concentrations, it has been used in antiacne formulations and in the treatment of anti-aging effects on photodamaged skin. The aim of the present study was to determine the variation profile of in vitro release of tretinoin, in order to establish the drug's partition coefficient between its carrier and the stratum corneum. The samples studied were formulations of tretinoin 0, 05% in carbopol 940 (a synthetic polymer), sodium carboxymethylcellulose (a semisynthetic polymer), and carob gum (a natural polymer) gels. The release profiles obtained from these formulations were compared to release profiles of retinoid creams. The formulations studied exhibited both good chemical and physical stabilities when submitted to rheological determinations, pH measurements, and drug dosage, throughout a 6-month period. The obtained results show that identical polymer viscosities result in identical release profiles; however, the release kinetics of tretinoin varies strongly in the way in which the drug is incorporated in the formulation (whether it is a solution or a suspension).  相似文献   
9.
This paper uses a rotating-beam-sensor structure to show that the extrinsic stress from the mismatch in expansion coefficient between the aluminum and the silicon substrate dominates over the compressive stress from the sputter growth. Sintering the layers at temperatures above 150/spl deg/C reduces this compressive stress due to the action of creep. Calibration of the rotation of the device has been undertaken by direct comparison to high resolution X-ray-diffraction measurements and these show that the sensor has a resolution better than 2.8 MPa. Furthermore, we have used the sensor to investigate the variation of in-plane stress with the compliance of the intermetal dielectric, by directly comparing sensors fabricated on SiO/sub 2/ and polyimide layers.  相似文献   
10.
In this paper we report the encapsulation of the compound 4′,7‐dihydroxyflavylium in a water‐permeable crosslinked poly(2‐hydroxyethyl methacrylate) matrix. The water permeability of the polymer and its transparency allow the use of pH and light stimuli to attain different states on the network defined by the various chemical reactions (multistate/multifunctional system). Unlike in water, in the polymer the compound 4′,7‐dihydroxyflavylium encapsulated exhibits a thermal barrier between the cis‐ and trans‐chalcones, a necessary requirement to define a write–read–erase cycle.  相似文献   
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