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211.
McNtcp.24 cells are rat hepatoma cells that were made competent to take up conjugated bile acids actively from the culture medium. Treatment of McNtcp.24 cells with certain species of bile acids caused significant changes in cell structure. Incubation of McNtcp.24 cells in medium containing 100 microM taurocholic acid induced a profound alteration of cellular morphology. Very larger vesicles, visible by phase contrast microscopy, were the most prominent feature of bile acid-treated McNtcp.24 cells. Staining of cells with Oil red O and filipin indicated that the vesicles did not contain neutral lipids or free cholesterol. The vesicles remained in the cells after efflux of radiolabeled taurocholic acid from bile acid loaded cells, indicating that these structures are not intracellular stores of bile acids. Electron microscopic analysis of bile acid-treated McNtcp.24 cells confirmed that the vesicles were localized within the cells. Taurine-conjugated bile acid species were generally potent inducers of the morphological changes, although tauroursodeoxycholic acid did not have a significant effect. Unconjugated bile acid species were ineffective or only mildly effective. Bile acid treatment also caused profound alteration of mitochondrial structure. Surprisingly, there was no significant effect on the ability of treated cells to oxidize fatty acids. The bile acid-treated cells remained viable and upon withdrawal of bile acids from the culture medium, the cells returned to normal morphology by 24 h. The morphological changes observed after treatment of McNtcp.24 with bile acids are reminiscent of the morphological changes observed in hepatocytes following induction of cholestasis.  相似文献   
212.
Partial equilibrium logic (PEL) is a new nonmonotonic reasoning formalism closely aligned with logic programming under well-founded and partial stable model semantics. In particular it provides a logical foundation for these semantics as well as an extension of the basic syntax of logic programs. In this paper we describe PEL, study some of its logical properties and examine its behaviour on disjunctive and nested logic programs. In addition we consider computational features of PEL and study different approaches to its computation.  相似文献   
213.
In this paper, we conducted a comparative study of how social organization takes place in a wasp colony and OSS developer communities. Both these systems display similar global organization patterns, such as hierarchies and clear labor divisions. As our analysis shows, both systems also define interacting agent networks with similar common features that reflect limited information sharing among agents. As far as we know, this is the first research study analyzing the patterns and functional significance of these systems' weighted-interaction networks. By illuminating the extent to which self-organization is responsible for patterns such as hierarchical structure, we can gain insight into the origins of organization in OSS communities.  相似文献   
214.
We investigate the monitoring of a process subject to minimum mean‐squared error feedback control using cumulative score (Cuscore) charts. Specifically, we design Cuscore statistics to discover spike, step, bump, and ramp signals hidden in non‐stationary disturbance for feedback‐controlled processes. We develop the adjustment and monitoring policies for combinations of process dynamics, disturbance, and signal that are practical in industry. We also address issues of detection probabilities and distributions using simulation. A manufacturing case study is used to illustrate the utility of the Cuscore approach. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
215.
Alterations in plasmatic lipid profile are known to be risk factors for atherosclerotic disease and have been associated with obesity. This research was designed in order to study the incidence of these alterations in obese children and adolescents according to two different reference patterns. Analyses of seric levels of Total Cholesterol (CT) and fractions and of Triglycerides (TG) were done. The sample included 74 obese children and adolescents with average age equal to 11 years and 10 months for boys and 10 years and 9 months for girls and with mean weight/height ratio (W/H) equal to 151 and 149% for boys and for girls, respectively. Plasmatic lipid values obtained were classified according to the American Heart Position Statement Circulation (AHPSC) and to Kwiterovich reference patterns. It was observed that patients with abnormal seric HDL-cholesterol (HDL) levels had a significantly greater (W/H) then the other group. It was also noticed that a greater number of individuals presented abnormal or borderline plasmatic lipid levels (91.9%), specially HDL (93.6%) and TG (67.6%), according to Kwiterovich than AHPSC. Obesity showed to be an important factor in determining lipid profile values and should be included as a variable to indicate screening of these lipoproteins in childhood and adolescence.  相似文献   
216.
Huitlacoche is the ethnic name applied to the young fruiting bodies (galls) of the fungus Ustilago maydis, which causes common smut of maize (Zea mays L). Biologists and agronomists have historically used U. maydis as a model to study a wide array of genetic, physiological, ecological, and phytopathological phenomena. In Mexico and other Latin American countries, huitlacoche has been used traditionally as human food, being highly regarded as an interesting dish or condiment. The food potential of huitlacoche is described here in terms of its chemical composition, which includes carbohydrates, proteins, fats, vitamins, and minerals. In addition, essential amino acids (especially lysine) and fatty acids (linoleate) are present in huitlacoche in considerable levels, adding to its nutritional attributes. The feasibility of growing U. maydis in submerged agitated culture has yielded a variety of fermentation products, including essential amino acids, proteins, vitamins, and flavorings, among others. Recent interest in developing huitlacoche as a cash crop has come from increasing acceptance by the North American public, who prize it as a new delicacy. However, research efforts are still needed to determine the biological factors involved in the establishment of U. maydis as a pathogen on the maize plant. This review deals with the role of huitlacoche as a food source, implicating the biological components that will determine the development of technologies for large scale production.  相似文献   
217.
The fifteenth edition of the EuroFoodChem conference, entitled “Food for the Future: The contribution of chemistry to improvement of food quality” took place in Copenhagen, Denmark from the 5th to the 8th of July 2009. The conference was organised by the Food Chemistry Division of the European Association of Chemical and Molecular Sciences (EuCheMS) and the Faculty of Life Sciences at the University of Copenhagen (LIFE-UC).  相似文献   
218.
International development programing is increasingly integrating agriculture and nutrition goals, while attempting to demonstrate ‘impacts at scale’ and value for money. These multiple goals create complexities, both from a conceptual viewpoint and a more operational perspective. This article uses systems theory to examine the mobile Nutrition program (mNutrition), which aims to improve nutrition, food security and livelihoods for rural women and children, through mobile phone-based information services. The paper specifically uses mNutrition’s work in Malawi as a case study. The systems approach reveals that, as a complex system with numerous sub-components and tensions among different goals, the mNutrition program tended to minimize connections between its sub-systems (such as content development and mobile service development processes) in order to speed up movement towards the global planned outcomes. We argue that this is likely to have multiple impacts on outcomes, including on overall effectiveness and the relevance and sustainability of the mobile message content.  相似文献   
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