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Cytochrome P450 monooxygenases (P450s) are ubiquitous heme-thiolate proteins that have potential biotechnological application. Thermostable-P450s that can withstand hostile industrial conditions, such as high temperatures, extremes of pH and organic solvents, are needed for biotechnological usage. Here, for the first time, we report a large number of thermostable-P450s from two thermophilic biomass-degrading fungi, Myceliophthora thermophila and Thielavia terrestris. Genome-wide P450 analysis revealed the presence of 79 and 70 P450s (P450ome) in T. terrestris and M. thermophila. Authentic P450s containing both the P450 signature domains (EXXR and CXG) were classified as follows: T. terrestris (50 families and 56 subfamilies) and M. thermophila (49 families and 53 subfamilies). Bioinformatics analysis of P450omes suggested the presence of a large number of thermostable-P450s. Based on aliphatic index cut-off (>90), 14 and 11 P450s were determined to be thermostable in T. terrestris and M. thermophila. Among the thermostable P450s, six P450s from T. terrestris and three from M. thermophila had a melting temperature (Tm) of >65 °C, suggesting their hyperthermal tolerance. Analysis of the instability index of two ascomycete P450omes revealed the presence of 12 and 19 in vitro stable P450s in T. terrestris and M. thermophila. Overall, six P450s from T. terrestris and four from M. thermophila showed both thermal tolerance and in vitro stability. Thermophilic ascomycetes P450s are of potential interest from a structural, mechanistic and biotechnological point of view, as five P450s showed higher thermal tolerance and five showed higher in vitro stability compared to the well-characterized thermostable-P450s CYP175A1 (bacteria) and CYP119 (archaea).  相似文献   
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A new series of [4-(2-phenylethenesulfonylmethyl)phenyl]quinazolin-4-yl-amines was prepared and tested for its in vitro cytotoxic activity against a panel of 12 human cancer cell lines. Compounds 9, 15, 24 and 31 showed good in vitro activity and were further tested for their in vivo efficacy in the HT-29 human colon adeno carcinoma xenograft model. Compound 9 exhibited promising activity in this model. Dose-response studies for this compound against HT-29 human colon adeno carcinoma xenografts at 100, 200 and 400mg/kg doses were performed.  相似文献   
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The aim of the study was to evaluate meiotic maturation, and expression of genes coding for oocyte secreted factors (GDF9, BMP15, TGFBR1, and BPR2) and apoptosis (BCL2, BAX and P53) after vitrification of immature goat cumulus oocyte complexes (COCs) and in vitro maturation. COCs were vitrified in a solution containing ethylene glycol, dimethyl sulfoxide and sucrose using either a conventional straw (CS), open pulled straw (OPS), cryoloop (CL), hemistraw (HS) or cryotop (CT). Freshly collected COCs (Control), COCs exposed to vitrification and dilution solutions without cryopreservation (EC) and vitrified-warmed COCs were matured in vitro for 27h. The viability of vitrified-warmed COCs 2 h post warming and in vitro maturation was similar for CL, HS and CT. The proportion of oocytes that extruded a 1st polar body and reached TI/MII was significantly higher with CT and HS followed by CL, OPS and CS. Gene expression of GDF9, BMP15, BMPR2, BAX and P53 were comparable to control levels for OPS, CL, HS and CT. The gene expression pattern in CS vitrified COCs was by contrast changed in that GDF9, BMP15, TGFBR1 and BAX were up regulated and BMPR2, BCL2 and P53 down regulated. In conclusion immature goat COCs vitrified using CT and HS showed that viability, maturation rates and expression of genes coding for oocyte secreted factors and apoptosis were similar to non-vitrified controls.  相似文献   
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We recently demonstrated that perfluorooctanoic acid (PFOA), a volatile surfactant, is as effective as sodium dodecyl sulfate at solubilizing the membrane proteins. PFOA can be removed by repeated evaporation prior to mass spectrometry analysis. However, the removal of PFOA by evaporation is a lengthy process that takes approximately 6 h. Toward the goal of decreasing the length of time required to remove PFOA from protein digests, we tested the efficiency of PFOA removal and subsequent peptide recovery using strong cation exchange (SCX) chromatography, hydrophilic interaction chromatography (HILIC), fluorous solid phase extraction (FSPE), and anion exchange (ANX) chromatography. We found that all these chromatographic techniques except ANX chromatography remove PFOA thoroughly from protein digest. Peptide recovery rates from the SCX chromatography varied widely; nonacidic peptides were recovered at a rate of up to 95%, while acidic peptides were recovered at a rate of less than 10%. On the other hand, acidic peptides were recovered well from HILIC, while peptides whose pIs are greater than 6 were recovered poorly. Peptide recovery using FSPE was considerably lower, less than 10% for most of the peptides. These results indicate that the SCX and HILIC chromatography provide a more rapid alternative to the evaporation method for applications in which recovery of entire set of peptides is not required.  相似文献   
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Sheep have a variable ability to resist gastrointestinal nematode infection, but the key factors mediating this response are poorly defined. Here we report the first large-scale application of quantitative proteomic technologies to define proteins that are differentially abundant between sheep selectively bred to have an enhanced (resistant) or reduced (susceptible) ability to eliminate nematodes. Samples were collected from the abomasal mucosa three days after experimental challenge with the nematode, Haemonchus contortus. This timing reflects the initial interaction of host and parasite, and the tissue represents the immediate interface. We identified and quantified more than 4400 unique proteins, of which 158 proteins showed >1.5 fold difference between the resistant and susceptible sheep. Trefoil factor 2, a member of RAS oncogene family (RAP1A) and ring finger protein 126 were amongst the proteins found to be highly abundant in the abomasal surface of resistant sheep, whereas adenosine deaminase and the gastrokine-3 like precursor were found at higher levels in susceptible sheep. Construction of gut proteome interaction networks identified mitochondrial function and energetic partitioning as important components of an effective nematode eliminating response. The differentially abundant proteins may be useful targets for phenotypic tests that aim to identify sheep with an enhanced ability to resist nematode infection.  相似文献   
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