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131.
Seon-Soo Kim Hyun-Jung Byun Sang-Hoon Kim Han-Hyoung Lee Suk Jun Lee Sang Joon Kim Chung-Gyu Park Taehoon Chun 《Biotechnology letters》2010,32(2):203-208
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
132.
Haofan Wang Youngjoo Byun Cyril Barinka Mrudula Pullambhatla Hyo-eun C. Bhang James J. Fox Jacek Lubkowski Ronnie C. Mease Martin G. Pomper 《Bioorganic & medicinal chemistry letters》2010,20(1):392-397
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
133.
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
134.
Seon-Yeong Kwak Jin-Mi Noh So-Hee Park Jang-Woong Byun Hye-Ryung Choi Kyoung-Chan Park Yoon-Sik Lee 《Bioorganic & medicinal chemistry letters》2010,20(2):738-741
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
135.
136.
Azhar Muhammad Quoc Viet Nguyen Hoon Cheol Park Do Y.Hwang Doyoung Byun Nam Seo Goo 《仿生工程学报(英文版)》2010,7(2):134-141
<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
137.
Thirumamagal BT Johnsamuel J Cosquer GY Byun Y Yan J Narayanasamy S Tjarks W Barth RF Al-Madhoun AS Eriksson S 《Nucleosides, nucleotides & nucleic acids》2006,25(8):861-866
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
138.
Kim J Kim H Lee Y Yang K Byun S Han K 《Journal of biochemistry and molecular biology》2006,39(3):329-334
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
139.
So-Yon Park Kyu -Jin Noh Jeong -Hoon Yoo Jae -Woong Yu Byun -Woo Lee Jung -Gon Kim Hak Soo Seo Nam -Chon Paek 《Journal of Plant Biology》2006,49(6):455-462
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
140.