Alzheimer's disease: insolubility of partially purified paired helical filaments in sodium dodecyl sulfate and urea   总被引：38，自引：0，他引：38  

D J Selkoe  Y Ihara  F J Salazar 《Science (New York, N.Y.)》1982,215(4537):1243-1245

A method is described for the partial purification of the paired helical filaments that accumulate progressively in human neurons in Alzheimer's disease (senile dementia). Paired helical filaments have unusual solubility characteristics, including insolubility in sodium dodecyl sulfate, urea, reducing agent, and guanidine, which prevent analysis of their molecular composition by gel electrophoresis. The paired helical filaments appear to contain covalent bonds other than disulfide, which cross-link individual filaments into a rigid intracellular polymer. Thus, paired helical filaments appear to represent an example in neurons of an insoluble cross-linked protein. Covalently cross-linked protein polymers occur in lens senile cataracts and in terminally differentiated skin keratinocytes, suggesting that there may be a common mechanism for remodeling some structural proteins during cell aging.  相似文献   

Global mammal conservation: what must we manage?     

Ceballos G  Ehrlich PR  Soberón J  Salazar I  Fay JP 《Science (New York, N.Y.)》2005,309(5734):603-607

We present a global conservation analysis for an entire "flagship" taxon, land mammals. A combination of rarity, anthropogenic impacts, and political endemism has put about a quarter of terrestrial mammal species, and a larger fraction of their populations, at risk of extinction. A new global database and complementarity analysis for selecting priority areas for conservation shows that approximately 11% of Earth's land surface should be managed for conservation to preserve at least 10% of terrestrial mammal geographic ranges. Different approaches, from protection (or establishment) of reserves to countryside biogeographic enhancement of human-dominated landscapes, will be required to approach this minimal goal.  相似文献   

Pharmacokinetics of intramuscular medetomidine in domestic sheep     

SBR  Kästner  D Demuth  R Bettschart-Wolfensberger  MK Akens  P Wapf  M Huhtinen† 《Veterinary anaesthesia and analgesia》2001,28(4):205-206

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Testing newly introduced ornamental plants to the arid climate of Kuwait     

MK Suleiman  NR Bhat  MS Abdal  RR Bellen 《Archives of Agronomy and Soil Science》2013,59(4):469-479

Thirty five ornamental plants were introduced into the Ahmadi Bioremediated Soil Park to screen and closely monitor the growth performance of these new introductions under the local environmental conditions. Out of these 35 plant species, 15 were planted in both bioremediated and agricultural soils to assess their suitability for growing in bioremediated soils. Data on vegetative growth was recorded to assess the performance of newly-introduced plants, whereas, the heat stress was documented of Bauhinia blakeana, where no visible effects of petroleum pollutants on plant growth were observed. Performance of each plant group is discussed separately in the text. Overall, plant survival was 72.73% for all plant groups. Generally, plants that failed to grow in bioremediated soil also did not survive in the agricultural soil, indicating that they were sensitive to heat stress more than the presence of petroleum contaminants in the soil. New plant species that were able to establish and perform satisfactorily will be used in greenery projects after they are fully naturalized to the prevailing climatic conditions.  相似文献   

Comparison of four radioactive probes for the diagnosis of potato spindle tuber viroid by nucleic acid spot hybridization   总被引：1，自引：0，他引：1  

L. F. Salazar  I. Balbo  R. A. Owens 《Potato Research》1988,31(3):431-442

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Life members     

Robert H. Johansen  Robert E. Thornton  W. J. Hooker  L. F. Salazar  C. R. Brown 《American Journal of Potato Research》1987,64(8):421-426

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Modified expression of virus resistance in potato in mixed virus infections     

Upali Jayasinghe  Carlos Chuquillanqui  Luis F. Salazar 《American Journal of Potato Research》1989,66(3):137-144

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Response of Potato (Solanum tuberosum L.) Germplasm to Water Stress Under In Vitro Conditions     

Macarena Barra  José Correa  Erika Salazar  Boris Sagredo 《American Journal of Potato Research》2013,90(6):591-606

Chile is center of origin and diversity of potato (Solanum tuberosum L.). Potato yield is affected under water stress conditions, so development of varieties with better tolerance to this stress is desirable. In this study we determined the differential response of INIA-Chile potato germplasm to water stress under in vitro assays with polyethylene glycol. One-hundred-and-fourty-nine genotypes were evaluated. Polyethylene glycol 4.8 % w/v was able to distinguish genotype response by considering the morphological variables (plantlet height, leaf and root number) and fresh and dry weight. Through multivariate statistical analysis, and in comparison with their respective controls without treatment, genotypes were clustered with high (74 – 79 %), intermediate (29 – 94 %), low (29 – 57 %), and very low (4– 28 %) water stress tolerance. The high-tolerance-response cluster was mainly made up of Chilean potato landraces. These results highlight the importance of this germplasm in food security, which could be directly cultivated and/or be used as progenitors to produce new varieties with increased tolerance to water-deficit stress.  相似文献   

Effect of Sodium Nitroprusside,a Nitric Oxide Donor,and Aminoguanidine,a Nitric Oxide Synthase Inhibitor,on In Vitro Development of Buffalo (Bubalus bubalis) Embryos     

S Saugandhika  D Kumar  MK. Singh  R Shah  T Anand  MS Chauhan  RS Manik  S K Singla  P Palta 《Reproduction in domestic animals》2010,45(5):931-933

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seco-Briarellinone and Briarellin S, Two New Eunicellin-Based Diterpenoids from the Panamanian Octocoral Briareum asbestinum     

Jos�� F��lix G��mez-Reyes  Ana Salazar  H��ctor M. Guzm��n  Yisett Gonz��lez  Patricia L. Fern��ndez  Armando Ariza-Castolo  Marcelino Guti��rrez 《Marine drugs》2012,10(11):2608-2617

Two new eunicellin-based diterpenes, seco-briarellinone (1) and briarellin S (2), and a known seco-asbestinin (3) have been isolated from the methanolic extract of the common octocoral Briareum asbestinum collected in Bocas del Toro, Caribbean of Panama. The structures and relative stereochemistry of the compounds were defined using extensive spectroscopic analysis including 1D, 2D-nuclear magnetic resonance (NMR) and high-resolution mass spectrometry (HRMS). compounds 1 and 2 displayed anti-inflammatory properties inhibiting nitric oxide (NO) production induced by lipopolisacharide (LPS) in macrophages with an Inhibitory concentration 50% (IC₅₀) of 4.7 μM and 20.3 μM, respectively. This is the first report of briarellin diterpenes containing a ketone group at C-12.  相似文献