Recognizing existing models     

Rosenberg WJ 《Science (New York, N.Y.)》2012,335(6067):401

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Retrobulbar abscess in an infant rhesus monkey.     

D P Rosenberg  P Blouin 《Journal of the American Veterinary Medical Association》1979,175(9):994-996

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Liming effects on the chemical composition of the organic surface layer of a mature Norway spruce stand (Picea abies [L.] Karst.)     

W Rosenberg  K.G.J NieropH Knicker  P.A de JagerK Kreutzer  T Weiß 《Soil biology & biochemistry》2003,35(1):155-165

The application of lime in a mature Norway spruce (Picea abies [L.] Karst.) forest in southern Germany induced major changes in the activity of soil organisms and root growth. Since this may influence the chemical compostion of the soil organic matter (SOM) of the organic surface layer, its composition and changes due to the treatment were examined in this study.Fine roots of Norway spruce have a relatively low content of extractable lipids, a low alkyl C content (¹³C CPMAS NMR) and a high ratio of non-cellulosic to cellulosic carbohydrates (NC/CC, carbohydrate determination by MBTH and gas chromatography analyses) as compared to needles. Furthermore, they show high ratios of suberin/cutin compounds (thermally assisted hydrolysis and methylation, (THM)) and high ratios of eicosanic acid/phytadiene I in their lipid extracts (pyrolysis-GC/MS).Liming (4 t ha⁻¹ dolomite) of a Norway spruce organic surface layer decreased the proportion of alkyl C, the alkyl C/O-alkyl C ratio, and the content of extractable lipids. The NC/CC ratio and the abundance of suberin relative to cutin components increased. The contribution of the chlorophyll component phytadiene I decreased in relation to eicosanic acid. These changes are attributed to increased fine root formation in the organic layer after liming. Furthermore, the presence of less degraded lignin (THM, peak ratio of 3,4-dimethoxybenzoic acid, methyl ester/3,4-dimethoxy-benzaldehyde) on the limed plot is explained by the increased input of relatively fresh fine root material. On the other hand, the decrease in the carbon-to-nitrogen ratio may be attributed to the higher microbial activity after liming.  相似文献   

Improving broad specificity hapten recognition with protein engineering   总被引：1，自引：0，他引：1  

Korpimäki T  Rosenberg J  Virtanen P  Karskela T  Lamminmäki U  Tuomola M  Vehniäinen M  Saviranta P 《Journal of agricultural and food chemistry》2002,50(15):4194-4201

Sulfa antibiotics (sulfonamides) are derivatives of p-aminobenzenesulfonamide that are widely used in veterinary medicine. Foods derived from treated animals may be contaminated with these drugs. However, current immunobased sulfonamide detection methods are unfit for screening of products because they are either too insensitive or specific for a few compounds only. An immunoassay capable of detecting all sulfas in a single reaction would be ideal for screening. For development of a binder capable of binding all sulfas, a protein engineering approach was chosen and the properties of monoclonal antibody 27G3 were improved with mutagenesis followed by selection with phage display. Several different mutant antibodies were isolated. The cross-reaction profile of the best mutant antibody was significantly improved over that of the wild-type antibody: it was capable of binding 9 of the tested 13 sulfonamides within a narrow concentration range and also bound the rest of the sulfas, albeit within a wider concentration range.  相似文献   

Oceans. U.S. ocean fish recovery: staying the course     

Safina C  Rosenberg AA  Myers RA  Quinn TJ  Collie JS 《Science (New York, N.Y.)》2005,309(5735):707-708

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Stink of Stinkpot Turtle Identified: ohgr-Phenylalkanoic Acids     

Eisner T  Conner WE  Hicks K  Dodge KR  Rosenberg HI  Jones TH  Cohen M  Meinwald J 《Science (New York, N.Y.)》1977,196(4296):1347-1349

The exocrine secretion of the "stinkpot turtle," Sternotherus odoratus, discharged by the animals in response to disturbance, contains four omega-phenylalkanoic acids (phenylacetic, 3-phenylpropionic, 5-phenylpentanoic, and 7-phenylheptanoic). The last two of these are new natural products. The first two are powerfully malodorous and responsible for the stench of the fluid. Lesser components, including several aliphatic acids, are also present. Only a few milligrams of secretion are discharged by a turtle at any one time. Although bioassays with fish suggest that the secretion has the potential to serve as a feeding deterrent to predators, it is argued that Sternotherus does not ordinarily discharge enough fluid to effect this action and may employ its secretion only as an aposematic signal that warns predators of its more generalized undesirability.  相似文献   

Kinetics of acetylcholine synthesis and hydrolysis in myasthenia gravis     

R N Rosenberg  D J Dalessio  J Tremblay  D Woodman 《Science (New York, N.Y.)》1971,173(997):644-645

Kinetic studies for choline-O-acetyltransferase (CAT) (E.C. 2.3.1.6) and acetylcholinesterase (E.C. 3.1.1.7) were performed on serum, skin fibroblasts in culture, and biopsied sartorius muscle from normal and myasthenic subjects. There was a significant decrease of CAT activity per milligram of protein in myasthenic muscle compared to normal muscle, and there was no difference in acetylcholinesterase activity per milligram of protein in the same muscle homogenates. Substrate concentration curves for acetyl coenzyme A and CAT also showed a significant reduction in the maximum rate of product formation (V(max)) per milligram of protein between myasthenic and normal muscle. It is postulated that binding of substrate to CAT is being inhibited by an inhibitor present in muscle.  相似文献   

The influence of phytoestrogens and oestradiol-17β on growth and sex determination in the European eel (Anguilla anguilla)     

Itai Tzchori  Gad Degani  Ronit Elisha  Rivka Eliyahu  Avshalom Hurvitz  Jacob Vaya  & Boaz Moav 《Aquaculture Research》2004,35(13):1213-1219

Under aquaculture conditions, European eels (Anguilla anguilla) produce a high percentage of males (80–95%) that normally stop growing at 100–200 g. Females continue to grow to 500–750 g and obtain higher market value. Therefore, increasing the percentage of females in a population would be beneficial to the culture of eels. The present study was carried out in order to examine the effect of oestradiol and phytooestrogens on sex differentiation and growth rate of eels. Juvenile European eels with undifferentiated gonads were fed pellets containing oestradiol‐17β (E2) or phytooestrogens for 100–150 days. Feeding E2 resulted in 50–61% increase in body weight compared with the control. Oestradiol‐17β and phytooestrogens both elevated significantly the percentage of females in the population. Feeding E2 at 20 mg kg^?1 feed resulted in 70% females, while lower concentration of E2 (2 mg kg^?1) resulted in only 30% after 100 days (Experiment 1). The same dose given for 150 days (Experiment 2) resulted in 88% females, indicating that both, the concentration and duration of E2 treatments had a significant effect on sex differentiation. Fish fed genistein at 2 mg kg^?1 for 100 days, resulted in 55% of females, but at a higher dose of 20 mg kg^?1 there were only 15% females. These results demonstrate that phytooestrogens can be used as alternatives to gonadal steroids for sex manipulation in eels, but the optimal concentrations and duration are still to be determined.  相似文献   

Variation of Growth and Disease Characters Between Clones of Potato (<Emphasis Type="Italic">Solanum tuberosum</Emphasis> L.)     

S. L. Nielsen  H. Bång  K. Kotkas  K. Kristensen  J. P. Palohuhta  V. Rosenberg  K. Tolstrup 《Potato Research》2007,50(2):97-114

The occurrence and magnitude of variation of selected characters in clones derived from meristem tips of four potato cultivars in field trials in three countries was assessed. Recorded were: the number of plants per plot; maturity of plants; skin and flesh colour; tuber deformity; time of emergence; flowering; number of stems and tubers per plant; tuber size, yield and dry matter percentage; and the occurrence of common scab. Far more significant differences between clones than could be expected by chance were found for the last eight characters. Most of the significant differences for number of stems per plant, number of tubers, yield and tuber size distribution were found in six clones of three cultivars and were repeated at different locations and in different years. It is concluded that significant clone differences exist and are repeated at independent locations over the years.  相似文献   

The major genetic determinants of HIV-1 control affect HLA class I peptide presentation     

International HIV Controllers Study  Pereyra F  Jia X  McLaren PJ  Telenti A  de Bakker PI  Walker BD  Ripke S  Brumme CJ  Pulit SL  Carrington M  Kadie CM  Carlson JM  Heckerman D  Graham RR  Plenge RM  Deeks SG  Gianniny L  Crawford G  Sullivan J  Gonzalez E  Davies L  Camargo A  Moore JM  Beattie N  Gupta S  Crenshaw A  Burtt NP  Guiducci C  Gupta N  Gao X  Qi Y  Yuki Y  Piechocka-Trocha A  Cutrell E  Rosenberg R  Moss KL  Lemay P  O'Leary J  Schaefer T  Verma P  Toth I  Block B  Baker B  Rothchild A  Lian J  Proudfoot J  Alvino DM 《Science (New York, N.Y.)》2010,330(6010):1551-1557

Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified >300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA-viral peptide interaction as the major factor modulating durable control of HIV infection.  相似文献