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51.
Sheep ovariectomy (OVX) alone or associated to steroid therapy, deficient diet, or hypothalamic–pituitary disconnection has proven to be of critical importance for osteoporosis research in orthopedics. However, the impact of specific variables, such as breed, age, diet, time after OVX, and other variables, should be monitored. Thus, the design of comparative studies is mandatory to minimize the impact of these variables or to recognize the presence of unwanted variables as well as to better characterize bone remodeling in this model. Herein, we conducted a systematic review of the last 10 years on PubMed, Scopus, and Web of Knowledge considering only studies on OVX sheep where a control group was present. Of the 123 records screened, 18 studies were included and analyzed. Results showed that (i) Merino sheep are the most exploited breed; (ii) 5–6 years of age is the most used time for inducing OVX; (iii) ventral midline laparotomy is the most common approach to induce OVX; (iv) OVX associated to steroid therapy is the most widely used osteoporosis model; and (v) success of OVX was mostly verified 12 months after surgery. In detail, starting from 12 months after OVX a significant decline in bone mineral density and in microarchitectural bone parameters as well as in biochemical markers were detected in all studies in comparison to control groups. Bone alteration was also site-specific on a pattern as follows: lumbar vertebra, femoral neck, and ribs. Before 12 months from OVX and starting from 3–5 months, microarchitectural bone changes and biochemical marker alterations were present when osteoporosis was induced by OVX associated to steroid therapy. In conclusion, OVX in sheep influence bone metabolism causing pronounced systemic bone loss and structural deterioration comparable to the situation found in osteoporosis patients. Data for treating osteoporosis patients are based not only on good planning and study design but also on a correct animal use that, as suggested by 3Rs principles and by ARRIVE guidelines, includes the use of control groups to be directly contrasted with the experimental group.  相似文献   
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This study focused to investigate the technological significance and the spoiling impact of diverse yeast strains, isolated from 'Bella di Cerignola' Italian table olives. Sixty-four isolates (belonging mainly to the species Candida famata and C. guilliermondii ) were studied to assess their growth at different temperatures (15, 25 and 37 °C), pHs (4.0, 5.0 and 9.5) and NaCl concentrations (0–10.0%) in lab medium. Their pectolytic, xylanolytic, lipolytic and catalase activities were also evaluated. Most of the yeasts showed a moderate pectolytic activity and were able to grow at pH 9.5 after 120 h of incubation. Salt and temperature were the most important environmental variables affecting yeast growth, which could exert a strong selective pressure on yeast population. Candida guilliermondii appeared more resistant to high salt concentrations, whereas C. famata was able to grow at 15 °C.  相似文献   
53.
A three variables–five levels central composite design was used to study the effects of pH (3.5, 4.0, 4.5, 5.0 and 5.5), cinnamaldehyde (0, 40, 80, 120 and 160 ppm) and heating temperature (80, 84, 88, 92 and 96 °C) on the spores of Alicyclobacillus acidoterrestris in malt extract broth (MEB). The heat shock resulted in a slight decrease of spore number from 3.2 to 2.5 log CFU mL−1 and occurred at 80–85 °C depending on the pH of the medium. Otherwise, cinnamaldehyde acted as an additional hurdle within the storage time; the critical amounts to be used were included in the range 41.35–44.42 ppm of cinnamaldehyde and were related positively to the pH, i.e. the critical amount of active compound decreased with the decreasing of the pH.  相似文献   
54.
Microbial characteristics under different atmospheres (vacuum, air, MAP1: 80% O2/20% CO2 and MAP2: 5% O2/65% N2/30% CO2) of poultry patties made of a mixture of ostrich, chicken and turkey meat were evaluated. The meat preparations were examined for changes in pH, colour properties (CIE L*, a*, b*), headspace composition, and bacterial counts (total viable cell, psychrotrophs, Enterobacteriaceae, lactic acid bacteria, Staphylococcus spp., Brochothrix thermosphacta, Pseudomonas spp.). The use of a high O2 atmosphere (MAP1) quickly leads to a loss of the appealing red colour. A limited alteration occurred with use of MAP2 and vacuum. For total viable counts a cell load higher than 8 log cfu g?1 for the samples packaged in air, MAP1 and MAP2 at the end of storage was observed. Whereas, for the vacuum packed samples the cell load never reached values higher than 8 log cfu g?1. Enterobacteriaceae, B. thermosphacta and Pseudomonas spp. cell load was less with the vacuum (7.60, 5.06 and 7.17 log cfu g?1, respectively) and MAP2 packaging (7.08, 5.60 and 7.40 log cfu g?1, respectively). However, the high microbial loads suggest that an improvement of the microbiological quality of poultry meat is necessary if the producers are going to propose this new meat preparation on the market.  相似文献   
55.
Natural antimicrobial compounds to control the quality decay of a fresh fish burger were studied. In particular, thymol, lemon extract and grape fruit seed extract (GFSE), at 20, 40 and 80 ppm, have been tested against the main spoilage microorganisms inoculated in fish burgers stored at 5 °C. The evolution of mesophilic and psychrotrophic bacteria was also monitored. The sensorial quality decay was determined by means of a panel test, which assessed odour, colour, texture, drip loss and general appearance during the storage period. Results show that all the active substances efficiently slowed down the growth of the spoilage microorganisms. In particular, GFSE was the most efficient against Photobacterium phosphoreum , Shewanella putrefaciens and mesophilic bacteria, whereas thymol was the most efficient against both psychrotrophic bacteria and Pseudomonas fluorescens . Microbial growth was the factor limiting fresh fish burger acceptability.  相似文献   
56.
The electrochemical behaviour of the macrocouple [titanium (shielded and unshielded) in deaerated acidic solution]/(titanium in aerated acidic solution) has been investigated in order to establish the reasons for the anomalous behaviour of titanium in the presence of shielded areas that has been reported in the literature and is sometimes observed in process equipment, and then to determine the conditions that favour the crevice corrosion of titanium in the same solutions On the basis of the experimental results, it has been possible to establish the criticality of stabilization of the macrocouple in 0.5 M H2SO4 at temperatures close to room temperature (in the sense that the macrocouple always tends towards conditions of complete passivity) and to interpret this behaviour on the basis of the theory of mixed potentials.  相似文献   
57.
Intact human erythrocytes incubated at 37 degrees C, pH7.4, release a sialoglycopeptide similar in its chemical composition, immunological and aggregation properties to the glycopeptide released by isolated 'ghost' membranes. The presence of ATP or reduced glutathione at physiological concentrations in the incubation medium of 'ghost' membranes inhibits this self-digestion process.  相似文献   
58.
ABSTRACT: The modeling of microbial growth behavior is of great relevance to the control of many industrial processes. In this work, a deterministic model to predict the growth curve of microorganisms, from inoculation to death, is presented. To validate the model a Saccharomyces cerevisiae strain has been used to conduct wine fermentation tests at 25 °C and at 2 different values of initial nitrogen concentration. Cell, nitrogen, ethanol and sugar concentration were monitored over a period of about 1200 h. The proposed model was simultaneously fitted with success to the 4 sets of available data. Moreover, due to the mechanistic structure of the proposed approach, it was possible to quantitatively describe the evolution of R1(t), R2(t), dE(t)/dt, dN(t)/dt, and dS(t)/dt during wine fermentation.  相似文献   
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