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101.
Although recent advances in medical and management strategies have reduced the mortality and morbidity rates related to subarachnoid haemorrhage (SAH), patients who survive a SAH may remain nevertheless affected by persistent cognitive and neuropsychological disturbances. The presence of these deficits has been attributed to the neurotoxic effects of the widespread subarachnoid blood. To assess the long-term neuropsychological and cognitive outcome related to subarachnoid blood extravasation per se we evaluated 20 patients affected by an unknown origin subarachnoid haemorrhage, and having SAH characteristics generally considered predictive of a favourable outcome. Patients were enrolled after a one-year interval from the initial insult, and were selected accordingly to a pre-designed protocol. We employed a complete battery of tests, assessing general cognitive and language functions, memory and construction ability, attention and vigilance, anxiety and depression. The results were compared with normal reference values and with performances of a socio-demographically homogenous sample of control volunteers. This study did not evidence any significant long-term cognitive and neuropsychological alteration after subarachnoid blood extravasation. These results indicate that the presence of subarachnoid blood initiate a number of secondary mechanisms of pathology.  相似文献   
102.
Celiac disease (CD) is one of the most common food intolerance. The only effective treatment for CD is a strict adherence to a gluten-free diet throughout the patient's lifetime. Gluten-free products are not widely available and are usually more expensive than their gluten-containing counterparts. There is, therefore, an urgent need to develop safe and effective therapeutic alternatives, to develop high-quality gluten-free products and to investigate the potential of the bread making biotechnology following ancient protocols which include long-time fermentation by selected sourdough lactic acid bacteria. This review describes the most relevant results related to biotechnologies that use selected sourdough lactic acid bacteria and probiotics as starters for sourdough fermentation to investigate their potential to decrease the risk of gluten contamination in gluten-free products. As shown by studies in vitro on celiac intestinal tissue and in vivo on CD patients, the bacterial proteolytic activity is rather promising not only as currently demonstrated for eliminating traces of contaminant gluten but probably also in perspective for the manufacture of tolerated baked goods.  相似文献   
103.
High-manganese austenitic steels were recently proposed to fabricate structural car body parts because of their very favorable combination of strength and ductility. They exhibit Portevin–Le Chatelier macroscopic plastic localization phenomena at the room temperature, as evidenced by the tensile curves first by the isolated stress peaks corresponding to the nucleation of deformation bands, which travel along the tensile axis, and then by serrations due to static deformation bands. The bands extend to the whole width of the specimen and cause a local temperature increase along with a slight surface relief. These plastic instabilities were studied during tensile tests at strain rates between 0.0004 and 0.04 s?1, with optical video recording, infrared thermography and optical extensometry, the latter based on digital image correlation. Two types of bands, type A and type C, were observed and are described.  相似文献   
104.
The conductive atomic force microscopy provided a local characterization of the dielectric heterogeneities in CaCu3Ti4O12 (CCTO) thin films deposited by MOCVD on IrO2 bottom electrode. In particular, both techniques have been employed to clarify the role of the inter- and sub-granular features in terms of conductive and insulating regions. The microstructure and the dielectric properties of CCTO thin films have been studied and the evidence of internal barriers in CCTO thin films has been provided. The role of internal barriers and the possible explanation for the extrinsic origin of the giant dielectric response in CCTO has been evaluated.  相似文献   
105.
We report a facile production of an up-converted surface-emitting DFB laser, performed by exploiting the versatility of sol-gel chemistry, the intriguing properties of well designed graded CdSe-CdS-Cd(0.5)Zn(0.5)S-ZnS colloidal quantum dots, and the scalability of nanoimprinting. Our laser prototype operates in the visible region following efficient optical pumping by either direct one-photon excitation or through the up-conversion of near infrared (NIR) light. By achieving cavity mode Q-factors in excess of 650 and retaining high lasing stabilities in air, this work highlights the feasibility of creating integrated lasing devices through solution based methods.  相似文献   
106.
107.

Scope

Modifications in intestinal microbiota and its metabolites, the short-chain fatty acids (SCFA) are main factors altering intestinal epithelial barrier integrity and eliciting the onset of a meta-inflammation observed in obesity. The present study is aimed at evaluating the efficacy of Enterococcus faecium (SF68) administration in counteracting the impairment of gut barrier and enteric inflammation in a model of diet-induced obesity, characterizing the molecular mechanisms underlying such beneficial effects.

Methods and Results

Male C57BL/6J mice, fed with standard diet (SD) or high-fat diet (HFD), are treated with SF68 (108 CFU day−1). After 8 weeks, plasma interleukin (IL)-1β and lipopolysaccharide binding protein (LBP) are measured, analysis of fecal microbiota composition and butyrate content as well as intestinal malondialdehyde, myeloperoxidase, mucins, tight junction protein, and butyrate transporter expression are investigated. After 8 weeks, SF68 administration counteracts the body weight gain in HFD mice, reducing plasma IL-1β and LBP. In parallel, SF68 treatment acts against the intestinal inflammation in HFD-fed animals and improves the intestinal barrier integrity and functionality in obese mice via the increase in tight junction protein and intestinal butyrate transporter (sodium-coupled monocarboxylate transporter 1 ) expression.

Conclusions

Supplementation with SF68 reduces intestinal inflammation and reinforces the enteric epithelial barrier in obese mice, improving the transport and utilization of butyrate.  相似文献   
108.
The effects of dietary supplementation in pigs with plant extract (PE) from Lippia spp., titrated in verbascoside (5 mg/kg feed), from weaning to slaughter (166 days), on carcass characteristics, meat quality, collagen characteristics, oxidative stability and sensory attributes of Longissimus dorsi (LD) muscle were examined. Ten pigs per treatment were slaughter at a live weight of 109.5 ± 1.4 kg. No influence on carcass characteristics, LD meat quality parameters and collagen characteristics were observed. Dietary PE increased (P < 0.001) α-tocopherol levels in LD muscle. Raw LD of pig fed PE showed lower (P < 0.001) lipid oxidation levels than controls. A reduction (P = 0.05) of fat odor and rancid flavor intensity in cooked LD muscle stored at 4 °C for 24 h was observed in the treated group. This study shows that PE is an effective antioxidant in pork meat, enhancing oxidative status and sensory attributes, without affecting other meat quality parameters.  相似文献   
109.
The effects of three different extraction methods, namely hydrodistillation, supercritical CO2 extraction (SCE) and hexane extraction on the yield, chemical composition and antimicrobial and antioxidant activities of lavender essential oil were investigated in this study. SCE produced a yield of 6.7 % (dry weight), which was comparable to that of solvent extraction (7.6 %), but significantly higher than that of hydrodistillation (4.6 %). The chemical composition of the oils showed considerable variations among the extraction methods, with linalool, linalyl acetate, camphor and borneol making up approximately 80 % of identified components in all extracts. Hexane extraction produced oils with the presence of waxes, colour pigments and albuminious materials with semi-solid consistency, while hydrodistillation extracts showed signs of thermal degradation. The SCE extracts had an aroma with the closest resemblance to the starting material, showing negligible thermal degradation, and exhibited significantly higher antioxidant activity than the hydrodistillation and hexane extracts. Oils produced by SCE and hydrodistillation had antimicrobial activities higher than hexane extracts. The results of this study demonstrate that SCE is a promising process for the extraction of lavender essential oil.  相似文献   
110.
Authentication of a food product is the procedure by which it is verified that the product matches the statements on the label, and that it conforms to what is established by regulations. This testing process includes analysis of the ingredients, determination of the geographical origin, and examination of the production methods. In particular, the use of rapid, effective and reliable analytical methods, when correctly applied to verify the authenticity and the traceability of the product, represents a valuable and irreplaceable tool for the authorities to carry out control functions. Tools and methodologies from scientific innovation and technological evolution can help to quickly locate particularly sophisticated frauds and adulterations. The feeding regime of livestock is a fundamental issue for the properties and safety of animal origin food, but this regime is often hidden from the consumer, making the zootechnical sector more prone to fraudulent practices. This review reports the results recently obtained in authentication of animal origin food by the application of stable‐isotope ratio analysis, the most promising analytical technique in this field.© 2012 Society of Chemical Industry  相似文献   
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