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131.
Distillers dried grains with solubles (DDGS) and corn gluten feed (CGF) are major coproducts of ethanol production from corn dry grind and wet milling facilities, respectively. These coproducts contain important nutrients, nevertheless, high levels of phosphorus (P). About 50-80% of the P in these products is in an organically bound form known as phytate. The phytate P in these products cannot be digested by nonruminant animals. Consequently, large quantities of phytate are deposited into the soil with the animal wastes which potentially could cause P pollution in soil and underground water resources. As regulations on the concentration of P material in ethanol production coproducts become more restrictive, measures need to be taken for effective extraction of phytate P from the coproducts to make these processes more environmentally compatible. Proper marketing of coproducts is critical to the overall economy of ethanol production facilities. In this study, distribution of P compounds in different streams of dry grind and wet milling operations was determined. In the dry grind process, the highest P concentration was found to be in the condensed distillers solubles (CDS) at about 1.34 wt.% (db). About 59% of P in this stream was in phosphates form. The highest concentration of P in the wet milling process was found in the light steep water at about 3.4 wt.% (db). In this stream, about 22% of P was attributed to phosphates.  相似文献   
132.
Lymphocyte activation gene-3 (LAG-3; CD223) is a transmembrane protein that is structurally similar to CD4. Since LAG-3 has a much higher binding affinity to MHC class II than that of CD4, several approaches using soluble LAG-3 were used to modulate immune responses by activation or inhibition of MHC class II expressing antigen presenting cells. In this study, we constructed soluble pig LAG-3 containing a critical binding site (D1 and D2 region) to MHC class II molecules, combined with a constant region of an immunoglobulin (Ig) heavy chain. Flow cytometry analyses indicated that soluble pig LAG-3 binds to both pig and human MHC class II molecules. Moreover, soluble pig LAG-3 can inhibit human lymphocyte proliferation in the human–pig xenogeneic mixed lymphocyte reaction in a dose-dependent manner. These results indicate that soluble pig LAG-3 may be useful for controlling the xenogeneic T cell immune responses between the human and pig.  相似文献   
133.
We report a strategy based on bioisosterism to improve the physicochemical properties of existing hydrophilic, urea-based GCPII inhibitors. Comprehensive structure–activity relationship studies of the P1′ site of ZJ-43- and DCIBzL-based compounds identified several glutamate-free inhibitors with Ki values below 20 nM. Among them, compound 32d (Ki = 11 nM) exhibited selective uptake in GCPII-expressing tumors by SPECT-CT imaging in mice. A novel conformational change of amino acids in the S1′ pharmacophore pocket was observed in the X-ray crystal structure of GCPII complexed with 32d.  相似文献   
134.
Distillers’ grains and corn fiber are the coproducts of the dry grind and wet corn milling industries, respectively. Availability of distillers’ grains and corn fiber at the ethanol plant and their high levels of lignocellulosic material make them attractive feedstock for conversion to ethanol. In this study, dilute sulfuric acid hydrolysis for the conversion of distillers’ grains and corn fiber to monomeric sugars and the formation of furfural were investigated. The extent of solubilization of biomass beyond monomeric sugars was also monitored. Biomass loadings in the range of 5–20 wt.% at 5% intervals, acid concentrations in the range of 0.5–1.5 vol.% at 0.5% intervals, and temperatures of 120 and 140 °C were studied. The highest yields of monomeric sugars were observed when the least amount of biomass loading was pretreated with the highest concentration of sulfuric acid and when the temperature was 140 °C. For the majority of the cases under consideration, the most effective period of hydrolysis appeared to be during the initial 20–30 min of the reaction. Formation of furfural during the course of hydrolysis was significantly lower at 120 °C and also lower for the distillers’ grains samples compared with the corn fiber samples. The total amount of the solubilized matter during the hydrolysis was significantly higher than the amount of the monomeric sugars. Analyses according to standard procedure were performed to quantify moisture, oil, carbohydrates, and ash in distillers’ grains and corn fiber samples. The total carbohydrate content of distillers’ grains and corn fiber were 57.7 ± 2.0 and 77.0 ± 1.0 wt.%, respectively. The presented results will provide a foundation for the suitability of the pretreated distillers’ grains and corn fiber for enzymatic hydrolysis step.  相似文献   
135.
Kojic acid–phenylalanine amide (KA–F–NH2), which showed an excellent tyrosinase inhibitory activity, did not inhibit melanogenesis in melanocyte due to its low cell permeability. To enhance its cell permeability by increasing lipophilicity, we prepared metal coordination compounds of KA–F–NH2 and characterized them by FT-IR and ICP analysis. The metal complex of KA–F–NH2 inhibited mushroom tyrosinase activity as much as KA–F–NH2 and reduced melanin contents in melanocyte efficiently.  相似文献   
136.
137.
<正> In an attempt to realize a flapping wing micro-air vehicle with morphing wings, we report on improvements to our previousfoldable artificial hind wing.Multiple hinges, which were implemented to mimic the bending zone of a beetle hind wing, weremade of small composite hinge plates and tiny aluminum rivets.The buck-tails of rivets were flared after the hinge plates wereassembled with the rivets so that the folding/unfolding motions could be completed in less time, and the straight shape of theartificial hind wing could be maintained after fabrication.Folding and unfolding actions were triggered by electrically-activatedShape Memory Alloy (SMA) wires.For wing folding, the actuation characteristics of the SMA wire actuator were modifiedthrough heat treatment.Through a series of flapping tests, we confirmed that the artificial wings did not fold back and arbitrarilyfluctuate during the flapping motion.  相似文献   
138.
Concise synthetic methods for synthesizing 3-carboranyl thymidine analogues (3CTAs) modified with cyclic and acyclic alcohols have been developed. The synthesis of these potential boron neutron capture therapy (BNCT) agents and their preliminary biological evaluation is described.  相似文献   
139.
RNAi (RNA interference) has become a popular means of knocking down a specific gene in vivo. The most common approach involves the use of chemically synthesized short interfering RNAs (siRNAs), which are relatively easy and fast to use, but which are costly and have only transient effects. These limitations can be overcome by using short hairpin RNA (shRNA) expression vectors. However, current methods of generating shRNA expression vectors require either the synthesis of long (50-70 nt) costly oligonucleotides or multi-step processes. To overcome this drawback, we have developed a one-step short-oligonucleotides- based method with preparation costs of only 15% of those of the conventional methods used to obtain essentially the same DNA fragment encoding shRNA. Sequences containing 19 bases homologous to target genes were synthesized as 17- and 31-nt DNA oligonucleotides and used to construct shRNA expression vectors. Using these plasmids, we were able to effectively silence target genes. Because our method relies on the one-step ligation of short oligonucleotides, it is simple, less error-prone, and economical.  相似文献   
140.
The identification of molecular markers and marker-aided selection are essential to the efficient breeding of drought-tolerant plants. However, because that characteristic is controlled by many quantitative trait loci, such markers that can screen and trace desirable barley genotypes in a segregating population or germplasm have not yet been determined. Relative water content has been used to estimate drought tolerance in plants because it is highly correlated with the drought index of yield. To develop reliable gene-specific markers for identifying tolerant versus susceptible genotypes, we performed suppression subtractive hybridization to identify candidate genes. We used two domestic barley cultivars, one having the highest RWC (drought-tolerant ‘Chalbori’) and the other having the lowest (drought-susceptible ‘Daebaekbori’). In response to dehydration at the early seedling stage, rapid upregulation ofDehydrin3 (Dhn3) andDhn4 occurred in the drought-tolerant genotypes, but not in the susceptible ones. Similar results were obtained with mature plants growing under frequent drought stress in the greenhouse. In addition,Dhn3 andDhn4 conferred higher drought tolerance when they were over-expressed in transgenicArabidopsis. Thus, in addition to using assessments of RWC, we propose thatDhn3 andDhn4 expressions can serve as drought-induced gene-specific markers to determine drought-tolerant barley genotypes at the seedling stage.  相似文献   
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