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131.
Carol N. Flores-Fernández Max Cárdenas-Fernández Dragana Dobrijevic Kosma Jurlewicz Amparo I. Zavaleta John M. Ward Gary J. Lye 《Biotechnology progress》2019,35(1):e2728
Proteases are the most important group of industrial enzymes and they can be used in several fields including biorefineries for the valorization of industrial byproducts. In this study, we purified and characterized novel extremophilic proteases produced by a Pseudomonas aeruginosa strain isolated from Mauritia flexuosa palm swamps soil samples in Peruvian Amazon. In addition, we tested their ability to hydrolyze distillers dried grains with solubles (DDGS) protein. Three alkaline and thermophilic serine proteases named EI, EII, and EIII with molecular weight of 35, 40, and 55 kDa, respectively, were purified. EI and EIII were strongly inhibited by EDTA and Pefabloc being classified as serine-metalloproteases, while EII was completely inhibited only by Pefabloc being classified as a serine protease. In addition, EI and EII exhibited highest enzymatic activity at pH 8, while EIII at pH 11 maintaining almost 100% of it at pH 12. All the enzymes demonstrated optimum activity at 60°C. Enzymatic activity of EI was strongly stimulated in presence of Mn2+ (6.9-fold), EII was stimulated by Mn2+ (3.7-fold), while EIII was slightly stimulated by Zn2+, Ca2+, and Mg2+. DDGS protein hydrolysis using purified Pseudomonas aeruginosa M211 proteases demonstrated that, based on glycine released, EIII presented the highest proteolytic activity toward DDGS. This enzyme enabled the release 63% of the total glycine content in wheat DDGS protein, 2.2-fold higher that when using the commercial Pronase®. Overall, our results indicate that this novel extremopreoteases have a great potential to be applied in DDGS hydrolysis. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2728, 2019 相似文献
132.
Brade Lore; Zych Krystina; Rozalski Antoni; Kosma Paul; Bock Klaus; Brade Helmut 《Glycobiology》1997,7(6):819-827
Monoclonal antibodies were generated against a synthetic glycoconjugatecontaining the trisaccharide 相似文献
133.
Y Collan T Torkkeli E Pesonen E Jantunen V M Kosma 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》1987,9(2):79-88
The application of morphometry in tumor pathology is discussed, e.g., its use in studying the biology of tumors, in creating tumor classification(s), in creating methods for the identification of a tumor in the diagnostic context, and in characterizing diagnostic histopathology in absolute terms. In traditional subjective diagnostic histopathology, reproducibility can be defined satisfactorily, but the definition of accuracy is ambiguous; in morphometric histopathology, a satisfactory definition is found for both concepts but it may be difficult to separate them in practice. Morphometric histopathology can study parameters measured from sections or parameters derived from the primary measurements through calculations. In the histopathology of tumors, the following parameters have turned out to be specially valuable: densitometric measurements of nuclei, nuclear area, perimeter and form factors, nucleolar parameters, the number of mitotic cells per area, the cellularity, the volume fraction of the epithelium, and parameters associated with the fraction of tumor tissue in the sample. The standard deviation or other moments of the distribution of these measurements can be more relevant than the mean values of the results. This indicates that more attention should be given to sampling rules, which are important in defining the efficiency of the methods. For rational application of morphometric methods, it is very important to make a distinction between group morphometry and diagnostic morphometry. The latter engenders numerous sources of variation (variation in section thickness, variation in tissue processing, variation in the techniques of measurement, interobserver variation, interlaboratory variation, variation due to subjective interpretation, etc.), which are usually better controlled in group morphometry. The influence on morphometric parameters of variation in section thickness and tissue shrinkage during processing are discussed. 相似文献
134.
The oligosaccharides, methyl 3-O-(sodium 3-deoxy-alpha-D-manno-2-octulopyranosylonate)-beta-D-ribofuranosid e, methyl 2-O-beta-D-ribofuranosyl-3-O-(sodium 3-deoxy-alpha-D-manno-2-octulopyranosylonate)-beta-D-ribofuranosid e, and methyl O-(sodium 3-deoxy-alpha-D-manno-2-octulopyranosylonate)-(2----2)-O-beta-D- ribofuranosyl-(1----2)-beta-D-ribofuranoside were prepared in high purity and good over-all yields. The constitutions of the trisaccharide derivatives correspond to the repeating units of the proposed linear and branched structures of the capsular polysaccharide(s) from Escherichia coli LP 1092. The alpha-KDO-(2----3)-beta-D-Ribf and alpha-KDO-(2----2)-beta-D-Ribf units were synthesized by a modification of the Helferich procedure using methyl (4,5,7,8-tetra-O-acetyl-3-deoxy-alpha-D-manno-2-octulopyranosyl bromide)-onate and appropriate beta-D-ribofuranosyl derivatives. The constitutional and configurational assignments were based on the 250-MHz 1H-n.m.r.-spectra of protected derivatives of the oligosaccharides. 相似文献
135.
Kosma Paul; Wugeditsch Thomas; Christian Rudolf; Zayni Sonja; Messner Paul 《Glycobiology》1995,5(8):791-796
The characterization of the S-layer glycoprotein of Bacillusihermoaerophilus revealed unexpected novelties. The isolationand purification procedure had to be changed due to completesolubility in aqueous buffers of the constituting S-layer protomers.Upon degradation of the S-layer glycoprotein by pronase andpurification of the products by gel filtration, ion-exchangechromatography, chromatofocusing and HPLC, one representativeglycopeptide fraction was selected for further characterization.From the combined evidence of composition analysis, chemicaldegradation, NMR spectroscopy experiments and comparison withsynthesized model substance, we propose the following repeatingunit structure of the glycan chain: 相似文献
136.
137.