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61.
In 3 experiments, the authors investigated the effects of to-be-remembered (TBR) and intervening list length on free recall to determine whether selective rehearsal could explain the previous finding that recall was affected only by TBR list length. In Experiments 1 (covert rehearsal) and 2 (overt rehearsal), participants saw 5- and 20-word lists and had to recall the list prior to that last presented list. In Experiment 3, either 1 or 2 lists were presented, and recall of TBR list was postcued. Recall proportion decreased with increased TBR list length. Moreover, the authors found extended recency effects when recall was replotted by when words were last rehearsed (Experiments 2 and 3) and an effect of intervening list length when rehearsal was reduced (Experiment 3). (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
62.
Xanthohumol (XN) is one of the major prenylflavonoids found in hop cones (Humulus lupulus L.). In this study, we investigated the cell growth inhibitory potential of XN on cultured human colon cancer cells. Cell proliferation was measured by sulforhodamine B staining. Poly(ADP-ribose)polymerase (PARP) cleavage, activation of caspases-3, -7, -8, and -9, and Bcl-2 family protein expression were detected by Western blot analyses. XN significantly reduced proliferation of the HCT 116-derived colon cancer cell line 40--16. Half-maximal inhibitory concentrations decreased from 4.1 microM after 24 h treatment to 3.6 and 2.6 microM after 48 and 72 h incubation, respectively. Treatment with 15 microM XN for 48 h and with 5 microM for 72 h led to the detection of the cleaved 89 kDa fragment of 116 kDa PARP as an indication of apoptosis induction. Concomitantly, we observed activation and cleavage of the effector caspases-3 and -7, induced by activation of the initiator caspases -8 and -9. Expression of anti-apoptotic Bcl-2 was down regulated when the cells were treated with XN for 48--72 h. We conclude that induction of apoptosis by downregulation of Bcl-2 and activation of the caspase cascade may contribute to the chemopreventive or therapeutic potential of XN.  相似文献   
63.
Point-of-purchase safety-based labeling guidance on the proper storage and handling of refrigerated ready-to-eat (RTE) meat and poultry products could help reduce the risk of listeriosis. Seniors and pregnant women are two population groups at increased risk of listeriosis due to suppressed or compromised immune systems. We conducted 11 focus groups with senior-aged women and women of childbearing age in Colorado and Ohio to assess consumer awareness of Listeria, storage practices of RTE meat products, perceptions regarding the acceptability and usefulness of common date and potential food safety labeling statements on RTE meat and poultry products, and food safety information needs. Storage times for opened and unopened RTE products varied widely, with opened products often being stored longer than recommended. Women in both age groups paid attention to date labels on packages but varied highly in their interpretation of the statements. "Use by" statements were considered clearer and more helpful than "Sell by" or "Best if used by" labels. Proposed food safety-based labeling statements listing "antilisterial" agents used in RTE products were not well received. However, labels giving consumers instructions on how long they could keep RTE products and when to discard them after opening were considered helpful and well received. Participants indicated the need for further information about Listeria and its control. Educational information at point-of-purchase and where seniors and pregnant women congregate are suggested. Manufacturers are encouraged to provide more complete information on the safe storage and use of ready-to-eat meat and poultry products on package labels.  相似文献   
64.
Food Science and Biotechnology - A rich source of nutrients, figs have a number of clinically validated benefits. This study aimed to evaluate the in vitro simulated gastrointestinal digestion, and...  相似文献   
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BACKGROUND: Metabolisation of carbon and nitrogen substrates is a key factor during the ripening process of white soft cheeses but has not previously been examined in terms of energy substrate efficiency. Such work could be useful to improve physiological knowledge concerning Geotrichum candidum, a yeast involved in the neutralisation of curd during ripening. Its behaviour was therefore examined during batch cultures on simple (glutamate) or complex (peptones) substrates as nitrogen and carbon sources and lactate as a second carbon source. RESULTS: In addition to their assimilation as carbon and nitrogen sources, G. candidum used peptides and amino acids as energy sources during growth in preference to lactate. Contrarily, during stationary state, lactate was preferred over peptides and amino acids for carbon dissimilation for energy supply, allowing the avoidance of ammonium production. Indeed, lactate dissimilation theoretically yields 15 adenosine triphosphates (ATPs), while only nine ATPs are theoretically yielded during the dissimilation of an amino acid such as glutamate. CONCLUSION: This behaviour can be considered as an energy‐saving response. Indeed, the use of peptides and amino acids as energy sources in addition to being used as carbon and nitrogen sources during G. candidum growth can be related to its deaminating activity and was in agreement with the better energy efficiency expected from utilisation of the same substrate as both carbon and energy source. Contrarily, the better efficiency of lactate dissimilation led to its use during stationary state instead of peptides and amino acids. Copyright © 2008 Society of Chemical Industry  相似文献   
67.
The effects of the reducing sugars (glucose and lactose) and the non-reducing sugar (sucrose), heated in combination with soy protein isolate (SPI) at neutral pH, on the physicochemical and rheological properties of SPI were determined. After formation of gels induced by glucono-δ-lactone (GDL), the textural profile and physicochemical bonds of the non-heated and heated SPI gels were investigated. The gelation of SPI was induced in three stages of processing that is similar to some tofu-making procedures. First, SPI was heated in the presence of sugars at neutral pH above the denaturation temperature of SPI; then gelation was induced by GDL at iso-electric pH and finally the acidic gels were heat treated again. Heat treatment with glucose at neutral pH resulted in SPI with higher glycation degree than with lactose, whereas SPI heat treated in the presence of sucrose was not glycated. GDL-induced gels of SPI glycated with glucose was more soluble in water than gels of SPI reacted with lactose, which in turn was more soluble than the control and gels of SPI heated in the presence of sucrose. This indicates a change in the net charge of proteins caused by the glycation reaction. Glucose and lactose had a protective effect on protein denaturation at neutral pH, albeit less than sucrose, resulting in GDL-induced gels with increased water holding capacity and reduced gel hardness than sucrose. Chemical analysis indicated that disulphide bonds were involved in maintaining the structure of the gels, and solubility profiles of gels in different buffers indicate that other types of covalent bonds besides disulphide bonds were formed in gels of glycated SPI, resulting in reduced gel elasticity.  相似文献   
68.
The a priori approach to psychological assessment advocates the selection of specific tests or the construction of clinical experiments that can serve to validate on a priori case formulation. The advantages of the a priori approach are discussed, and the 4 steps involved in its application are outlined: the initial interview, case formulation, validation, and development of a treatment plan. Illustrative cases of a 22-yr-old obese, diabetic woman and a 52-yr-old man with hypersensitivity to criticism are presented. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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A new method of introducing dithioester groups into the polymer chain of poly(cyclohexene oxide) is reported. It includes the use of diaryliodonium salt and an aromatic dithioacid as a redox couple to initiate the cationic polymerization of cyclohexene oxide. It was found that the dithioacid by itself cannot start the polymerization of cationic polymerizable monomers; however, in combination with a diaryliodonium salt, an exothermic reaction was produced, yielding a thiocarbonylthio‐functionalized polyether. Thermal profiles of the redox polymerizations were determined by means of optical pyrometry. A preliminary study showed that when the poly(cyclohexene oxide) functionalized with dithioester groups was introduced into the radical polymerization of styrene, the polystyryl growing radicals reacted with the dithioester‐functionalized polyether to form a block polymer. The amount of polyether actually incorporated into the block copolymer was calculated to be 70% of the initial amount of poly(cyclohexene oxide)/dithiobenzoic acid charged into the reactor. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
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