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71.
Maria Sofia Vieira-Rocha Pilar Rodriguez-Rodriguez Mariana Ferreira-Duarte Miguel Faria Joana Beatriz Sousa Manuela Morato Silvia Magdalena Arribas Carmen Diniz 《International journal of molecular sciences》2022,23(3)
Fetal stress is known to increase susceptibility to cardiometabolic diseases and hypertension in adult age in a process known as fetal programming. This study investigated the relationship between vascular RAS, oxidative damage and remodeling in fetal programming. Six-month old Sprague-Dawley offspring from mothers that were fed ad libitum (CONTROL) or with 50% intake during the second half of gestation (maternal undernutrition, MUN) were used. qPCR or immunohistochemistry were used to obtain the expression of receptors and enzymes. Plasma levels of carbonyls were measured by spectrophotometry. In mesenteric arteries from MUN rats we detected an upregulation of ACE, ACE2, AT1 receptors and NADPH oxidase, and lower expression of AT2, Mas and MrgD receptors compared to CONTROL. Systolic and diastolic blood pressure and plasma levels of carbonyls were higher in MUN than in CONTROL. Vascular morphology evidenced an increased media/lumen ratio and adventitia/lumen ratio, and more connective tissue in MUN compared to CONTROL. In conclusion, fetal undernutrition indices RAS alterations and oxidative damage which may contribute to the remodeling of mesenteric arteries, and increase the risk of adverse cardiovascular events and hypertension. 相似文献
72.
Karola B?hme Inmaculada C. Fern��ndez-No Jose M. Gallardo Benito Ca?as Pilar Calo-Mata 《Food and Bioprocess Technology》2011,4(6):907-918
Foodborne intoxications caused by the consumption of fish and other products of marine origin contaminated with bacterial
pathogens are an ever-present threat, either due to bacteria and/or its metabolites. In addition, the rapid spoilage of seafood
due to microbial activity, results in high economic losses. The development of the microbiota in seafood products depends
on the microbiological ambience of capture, processing and storage, and the applied preservation method. Thus, pathogenic
and spoilage bacterial species in seafood may come from the indigenous microbiota of the aquatic ambience or are introduced
by contamination during processing. Rapid and accurate bacterial species identification is essential for an effective control
program to ensure safety and quality of either processed or minimally processed seafood. In the present work, matrix-assisted
laser desorption ionization-time of flight mass spectrometry was successfully applied to identify 26 bacterial strains isolated
from fresh fish and processed seafood samples. The approach was based on the comparison of unknown spectra to a reference
spectral library and demonstrated to be a fast and accurate technique for bacterial species differentiation, which can be
used for the rapid identification of foodborne pathogens and spoilage bacteria potentially present in products of marine origin. 相似文献
73.
Antonia Picon Rocío Alonso Pilar Gaya Manuel Nuñez 《Food and Bioprocess Technology》2013,6(10):2820-2830
High-pressure treatment of raw goat milk curd was investigated as an alternative to thermal treatment of milk in cheese manufacture, and curd freezing as a procedure to surmount the seasonality of goat milk production. Experimental cheeses were made by mixing (70:30) fresh cow milk curd with frozen curd from pasteurized goat milk (PGC), frozen curd from raw goat milk (RGC), or frozen pressurized curd from raw goat milk (PRGC). Control cheese was made from a mixture (70:30) of pasteurized cow and goat milk. RGC cheese showed the highest counts of staphylococci, Gram-negative bacteria and coliforms, whereas PRGC cheese had maximum aminopeptidase activity, esterase activity, and overall proteolysis. Control cheese exhibited the highest dry matter content and peptide levels, the lowest concentration of free amino acids, the highest concentration of volatile compounds such as free fatty acids, alcohols and esters, and the firmest texture. Differences in sensory characteristics between experimental and control cheeses were of minor importance. High-pressure treatment of curd allowed the production of cheese of bacteriological quality similar to that of control cheese made using pasteurized milk, while curd freezing did not alter the sensory characteristics of experimental cheeses with respect to control cheese. 相似文献
74.
Monica Cavia‐Saiz Maria D Busto Maria Concepción Pilar‐Izquierdo Natividad Ortega Manuel Perez‐Mateos Pilar Muñiz 《Journal of the science of food and agriculture》2010,90(7):1238-1244
BACKGROUND: This study was designed to evaluate and compare antioxidant capacity and radical scavenging activity of naringin and its aglycone by different in vitro assays. The effects of flavanones on lipid peroxidation, glutathione (GSH) oxidation and DNA cleavage were also assessed. RESULTS: The results showed that naringenin exhibited higher antioxidant capacity and hydroxyl and superoxide radical scavenger efficiency than naringin. Our results evidenced that glycosylation attenuated the efficiency in inhibiting the enzyme xanthine oxidase and the aglycone could act like a more active chelator of metallic ions than the glycoside. Additionally, naringenin showed a greater effectiveness in the protection against oxidative damage to lipids in a dose‐dependent manner. Both flavanones were equally effective in reducing DNA damage. However, they show no protective effect on oxidation of GSH. CONCLUSION: The data obtained support the importance of characterizing the ratio naringin/naringenin in foods when they are evaluated for their health benefits. Copyright © 2010 Society of Chemical Industry 相似文献
75.
J. S. Felton Pilar Pais Cynthia P. Salmon Mark G. Knize 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1998,207(6):434-440
Levels of known heterocyclic amines vary from undetectable in many meats sold in fast food restaurants, to over 10 ng/g for
meats prepared in restaurants that cook food to order, to hundreds of nanograms per gram for some meats cooked under certain
home or laboratory conditions. To simulate the dry reactions that seem to occur at the meat surface we developed a model system
to mimic these processes. Mixtures of free amino acids, creatinine and glucose, simulating the composition of beef or chicken,
heated at 200 °C, form eight heterocyclic amines. Besides the commonly found 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline, 2-amino-3-methylimidazo[4,5-f]quinoline, 2-amino-3,4-dimethylimidazo[4,5-f]quinoline, 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine, 2-amino-1,6-dimethylimidazo[4,5-b]pyridine, 2-amino-1,5,6-trimethylimidazo[4,5-b]pyridine and 2-amino-1,6-dimethylfuro[3,2-e]imidazo[4,5-b]pyridine were also found. The calculated risk of consumption of heterocyclic amines is determined by the dietary dose, the
extrapolation of carcinogenic potencies from rodents to humans, and the extrapolation of high rodent doses to low human exposures.
Results suggest that DNA binding is linear with dose, but that the human DNA forms more adducts per unit dose than that of
the rat. Altogether, the risk appears to be equivalent to that for many carcinogens that are regulated.
Received: 23 April 1998 相似文献
76.
J. S. Felton Pilar Pais Cynthia P. Salmon Mark G. Knize 《European Food Research and Technology》1998,207(6):434-440
Levels of known heterocyclic amines vary from undetectable in many meats sold in fast food restaurants, to over 10 ng/g for
meats prepared in restaurants that cook food to order, to hundreds of nanograms per gram for some meats cooked under certain
home or laboratory conditions. To simulate the dry reactions that seem to occur at the meat surface we developed a model system
to mimic these processes. Mixtures of free amino acids, creatinine and glucose, simulating the composition of beef or chicken,
heated at 200 °C, form eight heterocyclic amines. Besides the commonly found 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline, 2-amino-3-methylimidazo[4,5-f]quinoline, 2-amino-3,4-dimethylimidazo[4,5-f]quinoline, 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine, 2-amino-1,6-dimethylimidazo[4,5-b]pyridine, 2-amino-1,5,6-trimethylimidazo[4,5-b]pyridine and 2-amino-1,6-dimethylfuro[3,2-e]imidazo[4,5-b]pyridine were also found. The calculated risk of consumption of heterocyclic amines is determined by the dietary dose, the
extrapolation of carcinogenic potencies from rodents to humans, and the extrapolation of high rodent doses to low human exposures.
Results suggest that DNA binding is linear with dose, but that the human DNA forms more adducts per unit dose than that of
the rat. Altogether, the risk appears to be equivalent to that for many carcinogens that are regulated.
Received: 23 April 1998 相似文献
77.
Silva AR Paulo EN Sant'Ana AS Chaves RD Massaguer PR 《International journal of food microbiology》2011,148(3):156-163
The objectives of this study were to isolate psychrotrophic clostridia from Brazilian vacuum-packed beef cuts (spoiled or not) and to identify the isolates by using 16S rRNA gene sequencing. Anaerobic psychrotrophic microorganisms were also enumerated and samples were collected to verify the incidence of psychrotrophic clostridia in the abattoir environment. Vacuum-packed beef cuts (n = 8 grossly distended and n = 5 non-spoiled) and environmental samples were obtained from a beef packing plant located in the state of São Paulo, Brazil. Each sample was divided in three subsamples (exudate, beef surface and beef core) that were analyzed for vegetative forms, total spore-forming, and sulfide reducing spore-forming, both activated by alcohol and heat. Biochemical profiles of the isolates were obtained using API20A, with further identification using 16S rRNA gene sequencing. The growth temperature and the pH range were also assessed. Populations of psychrotrophic anaerobic vegetative microorganisms of up to 1010 CFU/(g, mL or 100 cm2) were found in ‘blown pack’ samples, while in non-spoiled samples populations of 105 CFU/(g, CFU/mL or CFU/100cm2) was found. Overall, a higher population of total spores and sulfide reducing spores activated by heat in spoiled samples was found. Clostridium gasigenes (n = 10) and C. algidicarnis (n = 2) were identified using 16S rRNA gene sequencing. Among the ten C. gasigenes isolates, six were from spoiled samples (C1, C2 and C9), two were isolated from non-spoiled samples (C4 and C5) and two were isolated from the hide and the abattoir corridor/beef cut conveyor belt. C. algidicarnis was recovered from spoiled beef packs (C2). Although some samples (C3, C7, C10 and C14) presented signs of ‘blown pack’ spoilage, Clostridium was not recovered. C. algidicarnis (n = 1) and C. gasigenes (n = 9) isolates have shown a psychrotrophic behavior, grew in the range 6.2-8.2. This is the first report on the isolation of psychrotrophic Clostridium (C. gasigenes and C. algidicarnis) in Brazil. This study shows that psychrotrophic Clostridium may pose a risk for the stability of vacuum-packed beef produced in tropical countries during shelf-life and highlights the need of adopting control measures to reduce their incidence in abattoir and the occurrence of ‘blown pack’ spoilage. 相似文献
78.
Carmen Gómez-Guillen Teresa Solas Javier Borderías Pilar Montero 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1996,202(3):221-227
This paper seeks to compare the ultrastructure of gels made from frozen muscle of giant squid (Dosidicus gigas) at various temperatures with a number of different rheological parameters, with reference to a variety of added ingredients (non-muscle proteins and hydrocolloids) and to NaCl concentration. Interesting data on gel rheological properties were found where formulae containedl-carrageenan, starch and egg white, with a low salt concentration (1.5%). This seems to be because carrageenan forms an independent network which supports the principal structure formed by the fish protein; starch is incorporated into the network and retains water; and egg white forms a supplementary network which helps to improve rheological properties. 相似文献
79.
Sarah Laraichi Pilar Parra Rocío Zamanillo Ahmed El Amarti Andreu Palou Francisca Serra 《Lipids》2013,48(8):817-826
The scope of this study was to assess the impact of calcium and conjugated linoleic acid (CLA) supplementation on plasma fatty acid profiles and to evaluate potential synergistic effects of both compounds against dietary obesity. Mice separated into five experimental groups were followed: control (C), high-fat diet (HF), HF with calcium (Ca), HF plus CLA and HF with both Ca and CLA. Plasma metabolites and fatty acids were determined by commercial kits and gas chromatography, respectively. Both dietary calcium and CLA supplementation contributed to lower body fat gain under a HF diet. Maximum efficacy was seen with calcium; no additional effect was associated with the combined treatment with CLA. Plasma leptin, adiponectin and HOMA index were in accordance with an altered glucose/insulin homeostasis in the HF and HF + CLA groups, whereas control levels were attained under Ca-enriched diets. Plasma fatty acids showed minor changes associated to CLA treatment, but a high impact on PUFA was observed under Ca-enriched diets. Our results show that the mechanism underlying the anti-obesity effects of calcium supplementation is mediated mainly by changes in PUFA plasma profile. In addition, the lack of synergy on body weight reduction in combination with associated lipid profiles of calcium and CLA suggests that calcium may interfere with absorption and/or bioactivity of CLA, which can be of relevance when using CLA-fortified dairy products against human obesity. 相似文献
80.
A study was carried out to increase the CLA contents in ewes’ milk fat under field conditions by dietary means and to investigate
the extent of the changes and consequences for milk processing and cheese quality. During a 3-mon period, ewes’ bulk milk
samples were collected every week from two different herds. For the first 4 wk the ewes were fed a conventional diet. Then
the following 6 wk a supplement enriched in α-linolenate (whole linseed) was incorporated into the ovine diet. Finally, in
the last 3 wk the feeding was the same as in the first 4 wk. The FA profile in milk fat was monitored by GC, and the distribution
of CLA isomers was thoroughly tested by combining GC-MS of 4,4-dimethyloxazoline derivatives (DMOX) with silver ion-HPLC (Ag+-HPLC) of FAME. Reconstructed mass spectral profiles of CLA characteristic ions from DMOX were used to identify positional
isomers, and Ag+-HPLC was used to quantify them. An increase in total CLA in milk fat was observed, and total CLA remained elevated during
the weeks of enriched α-linolenate feeding. In our experimental conditions there was a linear relationship between trans-vaccenic acid (trans-11-octadecenoic acid; trans-11 18∶1) and 9-cis, 11-trans CLA in ewes’ milk fat. Concerning the CLA isomer profile, increases in the 11,13- and 12,14–18∶2 positional isomers were
considerable when linseed was included in the diet. Organoleptic characteristics of cheeses made with CLA-enriched milk did
not substantially differ from those made with nonsupplemented ewes’ milk. CLA total content and isomer profile did not change
during ripening. 相似文献