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211.
Lamiaceae is among the largest families of flowering plants with about 250 genera and over 7,000 species distributed around the world. It is considered as the important source of essential oils, for example, menthol, geraniol, eucalyptol, camphor and thymol. Therefore, it is imperative to study these economically important compounds under in vitro conditions for their sustainable and enhanced production. In addition to proven biological activities, essential oils from this family have recently been evaluated for anticancer activities and considered as a source of anticancer drugs. Mechanisms involved in the essential oils-mediated antiproliferative activity include cell cycle arrest, apoptosis and DNA repair mechanisms. Essential oils also act in the reduction of tumors, inhibiting metastasis and as anti-multidrug resistance molecules. The aim of this review is to assess the anticancer properties of essential oils obtained from different members of family Lamiaceae. The available reports on active components of essential oils and their effect on cancer type and cell line have been discussed. Biotechnological studies to improve the production of essential oils have also been highlighted. Various methods have been adopted to obtain essential oils under in vitro conditions from different plant species of family Lamiaceae, and their production is affected by culture conditions, cultivation mode, utilization of nutrient media and plant growth regulators. The literature survey suggests that essential oils obtained from family Lamiaceae have perspective for the development of new alternatives for disease treatment and prevention.  相似文献   
212.
This work demonstrates the obtention of Nb2O5 nanoparticles by the microwave-assisted hydrothermal synthesis method in a fast way and with the use of low temperatures. The heat treatment applied on the samples promotes the phase change in Nb2O5 from pseudohexagonal to orthorhombic as the temperature increases, with a particle size between 7.3 and 32.6 nm. The band gap of the samples decreases with increasing temperature, obtaining a minimum value of 3.04 eV at 800°C. Dye-sensitized solar cells (DSSC) were assembled using the Doctor Blade coating technique. The photovoltaic parameters of open-circuit voltage (Voc) and short-circuit current density (Jsc) were evaluated. The cells showed a photovoltaic response, demonstrating that Nb2O5 has a semiconductive potential. The DSSC have different characteristics regarding Jsc and Voc, showing that according to the temperature increase in the semiconductor sample, there is a decrease in the photovoltaic parameters of the cells.  相似文献   
213.
214.
The objective was to evaluate the effect of beta-lactoglobulin (beta-lg) polymorphism and seasonality on milk composition (fat, lactose, total solids, milk urea nitrogen, total protein, true protein, casein and somatic cell counts) of Holstein and Girolando cows. Milk and blood samples from 278 Holsteins cows and 156 Girolando cows were taken during two dry seasons and two rainy seasons, for milk composition analysis and to determine beta-lg genotypes, respectively. BB genotype was the most frequent for both breeds, followed by AA genotype for Holstein (BB>AA>AB) and by AB for Girolando cows (BB>AB>AA). No differences were found in milk compositional characteristics among genetic variants of beta-lg (AA, AB and BB) either between Holstein or Girolando cows. No association between milk composition and beta-lg genetic polymorphism was observed. During the dry season, independently of the breed considered, higher contents of lactose, true protein, casein and casein:true protein ratio were found.  相似文献   
215.
The objective of this study was to elucidate the controversial relationship between the molecular weight (MW) of chitosans and their antibacterial activity (upon different inoculum levels, at several concentrations). The influence of food components on the activity was also ascertained, as well as acceptance by a sensory panel. All the compounds tested exhibited antibacterial activity against Staphylococcus aureus and Escherichia coli. This activity was shown to be closely dependent on the inoculum level, MW and concentration used. Within 4h at 10(3) cells/mL, all five compounds, at every concentration (0.5%, 0.25% and 0.1%, w/v), proved to be bactericidal; for higher inocula, 0.1% (w/v) was only bacteriostatic; at 10(7) or 10(5) cells/mL, and independently of the inoculum level, 0.25% (w/v) of any chitooligosaccharide (COS) mixture was sufficient to reduce the E. coli initial population by at least 3 log cycles; COS never exhibited bactericidal action over S. aureus, unlike high and medium MW chitosans-which, at 0.5% (w/v), presented a bactericidal effect even against 10(7) cells/mL. When incorporated in liquid food matrices, medium and high MW chitosans maintained their activity, for both matrices and bacteria, although a slower activity was noticeable in milk; however, COS lost their activity upon both bacteria in milk after 4-8h. Furthermore, addition of chitosans to apple juice led to several unpleasant off-flavors, such as astringency and after taste--which increased in magnitude with MW.  相似文献   
216.
Extracellular vesicles (EVs) are important players for intercellular communication. EVs are secreted by almost all cell types; they can transfer information between nearby or distant cells, and they are highly abundant in body fluids. In this review, we describe the general characteristics of EVs, as well as isolation and characterization approaches. Then, we focus on one of the most relevant sources of EVs: the blood. Indeed, apart from EVs secreted by blood cells, EVs of diverse origins travel in the bloodstream. We present the numerous types of EVs that have been found in circulation. Besides, the implications of blood-derived EVs in both physiological and pathological processes are summarized, highlighting their potential as biomarkers for the diagnosis, treatment monitoring, and prognosis of several diseases, and also as indicators of physiological modifications. Finally, the applications of EVs introduced in the circulatory system are discussed. We describe the use of EVs from distinct origins, naturally produced or engineered, autologous, allogeneic, or even from different species and the effects they have when introduced in circulation. Therefore, the present work provides a comprehensive overview of the components, effects, and applications of EVs in blood.  相似文献   
217.
Ultrasonic wave propagation and the spray dryer technique were applied to study their effect on the physical and chemical properties of green banana starch. The results showed high resistant starch content, which was reduced by ultrasound treatment and also by spray drying. Both techniques increased the solubility, swelling power and water absorption capacity. The gels exhibited non-Newtonian shear-thinning behavior, since flow behavior index was less than one (n < 1). Ultrasound wave propagation reduced yield stress and consistency coefficient in starch gels. Under oscillatory shear, all gels exhibited solid-like viscoelastic behavior, storage modulus was higher than loss modulus to entire frequency range (G′ > G′′), which was confirmed by the Cox-Merz experiment that showed that the complex dynamic viscosity was greater than the apparent viscosity in all samples. The gelatinization temperature was mainly influenced by drying technique and ultrasound treatment reduced the amount of energy required to gelatinize the starch.  相似文献   
218.
4-Chloro-N-(pyridin-2-ylmethyl)aniline (CPYA) was synthesized by a simple and inexpensive method and tested as a corrosion inhibitor in acid medium for mild steel by using gravimetric studies and electrochemical measurements. An average maximum efficiency of 96.0% was achieved at 4.59 mmol/L. Corrosion kinetic and thermodynamic parameters were also analyzed. Surface analyses (atomic force microscopy and scanning electron microscopy) show that protection is enabled by adsorption on the metal, forming a film. Quantum chemical calculations were performed to access information regarding the molecular structure in the corrosive medium and to support interpretation of the results obtained by experimental methods.  相似文献   
219.
Since the beginning of the HIV epidemic, research has been carried out to control the virus. Understanding the mechanisms of replication has given access to the various classes of drugs that over time have transformed AIDS into a manageable chronic disease. The class of protease inhibitors (PIs) gained notice in anti-retroviral therapy, once it was found that peptidomimetic molecules act by blocking the active catalytic center of the aspartic protease, which is directly related to HIV maturation. However, mutations in enzymatic internal residues are the biggest issue for these drugs, because a small change in biochemical interaction can generate resistance. Low plasma concentrations of PIs favor viral natural selection; high concentrations can inhibit even partially resistant enzymes. Food-drug/drug-drug interactions can decrease the bioavailability of PIs and are related to many side effects. Therefore, this review summarizes the pharmacokinetic properties of current PIs, the changes when pharmacological boosters are used and also lists the major mutations to help understanding of how long the continuous treatment can ensure a low viral load in patients.  相似文献   
220.
Novel ionic liquids and organic salts based on mono- or dianionic zoledronate and protonated superbases, choline and n-alkylmethylimidazolium cations, were prepared and characterized by spectroscopic and thermal analyses. Most of the prepared salts display amorphous structures and very high solubility in water and saline solutions, especially the dianionic salts. Among the zoledronate-based ionic compounds, those containing choline [Ch] and methoxyethylmethylimidazolium [C3OMIM] cations appear to have significant cytotoxicity against human osteosarcoma cells (MG63) and low toxicity toward healthy skin fibroblast cells. Because osteosarcoma is a bone pathology characterized by an increase in bone turnover rate, the results presented herein may be a promising starting point for the development of new ionic pharmaceutical drugs against osteosarcoma.  相似文献   
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