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991.
Relation of ATP and creatine phosphate to fast axoplasmic transport in mammalian nerve 总被引:1,自引:1,他引:0
—ATP and creatine phosphate (CP) levels in cat sciatic nerve maintained in vitro were measured. Anoxia produced by N2 or NaCN or the uncoupling of phosphorylation with DNP reduced the combined levels of ATP + CP to approximately one-half of control levels within 15 min. These agents also blocked fast axoplasmic transport in vitro within 15 min. A block of glycolysis with iodoacetic acid (IAA) reduced the combined levels of ATP + CP to approximately one half of control levels within 1.5–2 h and exposure of nerve in vitro to IAA caused a block of fast axoplasmic transport within the same interval. The correlation of the time at which block of transport occurred with the fall in the level of high-energy phosphates is consistent with the hypothesis that ATP supplies the energy required by the mechanism underlying fast exoplasmic transport. 相似文献
992.
Problem Management Plus (PM+): pilot trial of a WHO transdiagnostic psychological intervention in conflict‐affected Pakistan 下载免费PDF全文
993.
Regine Kluge Lidia Chavdarova Martha Hoffmann Carsten Kobe Bogdan Malkowski Fran?oise Montravers Lars Kurch Thomas Georgi Markus Dietlein W. Hamish Wallace Jonas Karlen Ana Fernández-Teijeiro Michaela Cepelova Lorrain Wilson Eva Bergstraesser Osama Sabri Christine Mauz-K?rholz Dieter K?rholz Dirk Hasenclever 《PloS one》2016,11(3)
Purpose
The five point Deauville (D) scale is widely used to assess interim PET metabolic response to chemotherapy in Hodgkin lymphoma (HL) patients. An International Validation Study reported good concordance among reviewers in ABVD treated advanced stage HL patients for the binary discrimination between score D1,2,3 and score D4,5. Inter-reader reliability of the whole scale is not well characterised.Methods
Five international expert readers scored 100 interim PET/CT scans from paediatric HL patients. Scans were acquired in 51 European hospitals after two courses of OEPA chemotherapy (according to the EuroNet-PHL-C1 study). Images were interpreted in direct comparison with staging PET/CTs.Results
The probability that two random readers concord on the five point D score of a random case is only 42% (global kappa = 0.24). Aggregating to a three point scale D1,2 vs. D3 vs. D4,5 improves concordance to 60% (kappa = 0.34). Concordance if one of two readers assigns a given score is 70% for score D1,2 only 36% for score D3 and 64% for D4,5. Concordance for the binary decisions D1,2 vs. D3,4,5 is 67% and 86% for D1,2,3 vs D4,5 (kappa = 0.36 resp. 0.56). If one reader assigns D1,2,3 concordance probability is 92%, but only 64% if D4,5 is called. Discrepancies occur mainly in mediastinum, neck and skeleton.Conclusion
Inter-reader reliability of the five point D-scale is poor in this interobserver analysis of paediatric patients who underwent OEPA. Inter-reader variability is maximal in cases assigned to D2 or D3. The binary distinction D1,2,3 versus D4,5 is the most reliable criterion for clinical decision making. 相似文献994.
The aim of the present study was to isolate a variety of quorum quenching bacteria (QB) from the rhizosphere and phyllosphere of three agricultural plants using minimal medium (MM)- and non-minimal medium (NM)-based methods. The members of the Pseudomonas genus constituted the most abundant QB genus, particularly in the rhizospheres of all plant samples and showed the highest quorum quenching (QQ) activity according to a screening assay using a biosensor and 3-oxo-C6-HSL (as an important quorum sensing signal in many phytopathogenic bacteria). In addition, QQ-Pseudomonas were recognised as versatile biocontrol agents against non-bacterial and bacterial plant pathogens, such as Pectobacterium carotovorum subsp. carotovorum (Pcc). Three types of quenching activities, including intracellular and extracellular enzymatic and non-enzymatic activities, were observed in QQ-Pseudomonas. Pseudomonas strains, particularly NM-isolated strains with extracellular activity, are the strongest QQ-based biocontrol agents. 相似文献
995.
Zikria Saleem Hamid Saeed Mobasher Ahmad Mahrukh Yousaf Hafsa Binte Hassan Ayesha Javed Nida Anees Sonu Maharjan 《PloS one》2016,11(2)
Pharmacists are the custodians of drugs; hence their education, training, behaviors and experiences would affect the future use of drugs at community and hospital pharmacies. Therefore, we aimed at evaluating the self-prescribing antibiotic trends, knowledge and attitudes among pharmacy and non-pharmacy students. We found that pharmacy students had higher risks of experiencing URIs related symptoms such as cough (RR; 1.7, p = 0.002), allergy (RR; 2.07, p = 0.03) and running nose (RR; 3.17, p<0.005), compared to non-pharmacy students -resulting in higher probabilities of selecting cough syrups (OR; 2.3, p<0.005), anti-histamines (OR; 1.8, p = 0.036) and anti-inflammatory/anti-pyretic (OR; 2.4, p<0.005) drugs. Likewise, bachelor’s degree pupils (OR; 2, p = 0.045), urban area residents (OR; 2.44; p = 0.002) and pharmacy students (OR; 2.9, p<0.005) exhibited higher propensities of antibiotic self-use–notable classes include, b-lactams (45.9%) followed by macrolides (26.5%) and augmentin (28.94%), respectively. Surprisingly, pharmacy and non-pharmacy students had higher odds of using antibiotics in common cold (OR; 3.2, p<0.005) and pain (OR; 2.37, p = 0.015), respectively. Unlike non-pharmacy students, pharmacy students were likely to select alternative therapy, such as Joshanda (OR; 2.22, p = 0.011) and were well acquainted with antibiotic hazards, with 77% reduction in risk of antibiotics re-use. In conclusion, university students exhibited antibiotic self-prescribing trends in conditions that does not warrant their use, thus are irrational users. The pharmacy education confers very little benefit to rational self-prescribing practices among students, while non-pharmacy students are more vulnerable to repeated antibiotic usage. Thus, the educational and training modules should be designed for university students to disseminate targeted information regarding the potential hazards of antibiotic self-use and importance of consultation with qualified and registered medical doctor/pharmacist before starting with antibiotics. 相似文献
996.
997.
To use adult somatic cloning technology in animal breeding, this technology should be complemented with nuclear donor cell cryopreservation. Two different conventional nonequilibrium methods (vitrification, V: 3.58M EG and 2.82M DMSO in PBS plus 20% FCS and rapid-freezing, RF: 0.25M sucrose, 2.25M EG and 2.25M DMSO in PBS plus 20% FCS) were assayed here on different cumuli types from rabbits and pigs. In rabbits, the cell proliferation capability of fully disaggregated cumuli was not affected by cryopreservation procedures (V: 100% and RF: 82%). Vitrified samples from partially or non-disaggregated cumuli showed the lowest proliferation frequencies (4% and 0%, respectively). In pigs, differences in cell proliferation capability were only observed between vitrified non-disagreggated cumuli and vitrified or rapid-frozen, fully disaggregated cumuli (72% vs 100% or 100%, respectively; P < 0.05). In both species, in vitro cultured sub-confluent samples were able to survive to a second cryopreservation treatment, maintaining the cell proliferation capability in nearly 50% of thawed samples. In conclusion, before cryopreservation, disaggregation of cumulus cells from both species into small clusters of cells improved their viability after thawing. These results allow us to efficiently, easily and rapidly store rabbit and pig cumulus cells, from selected high-merit females. 相似文献
998.
S. Diaz J.G. Hodgson K. Thompson M. Cabido J.H.C. Cornelissen A. Jalili G. Montserrat‐Martí J.P. Grime F. Zarrinkamar Y. Asri S.R. Band S. Basconcelo P. Castro‐Díez G. Funes B. Hamzehee M. Khoshnevi N. Prez‐Harguindeguy M.C. Prez‐Rontom F.A. Shirvany F. Vendramini S. Yazdani R. Abbas‐Azimi A. Bogaard S. Boustani M. Charles M. Dehghan L. de Torres‐Espuny V. Falczuk J. Guerrero‐Campo A. Hynd G. Jones E. Kowsary F. Kazemi‐Saeed M. Maestro‐Martínez A. Romo‐Díez S. Shaw B. Siavash P. Villar‐Salvador M.R. Zak 《植被学杂志》2004,15(3):295-304
Question: A set of easily‐measured (‘soft’) plant traits has been identified as potentially useful predictors of ecosystem functioning in previous studies. Here we aimed to discover whether the screening techniques remain operational in widely contrasted circumstances, to test for the existence of axes of variation in the particular sets of traits, and to test for their links with ‘harder’ traits of proven importance to ecosystem functioning. Location: central‐western Argentina, central England, northern upland Iran, and north‐eastern Spain. Recurrent patterns of ecological specialization: Through ordination of a matrix of 640 vascular plant taxa by 12 standardized traits, we detected similar patterns of specialization in the four floras. The first PCA axis was identified as an axis of resource capture, usage and release. PCA axis 2 appeared to be a size‐related axis. Individual PCA for each country showed that the same traits remained valuable as predictors of resource capture and utilization in all of them, despite their major differences in climate, biogeography and land‐use. The results were not significantly driven by particular taxa: the main traits determining PCA axis 1 were very similar in eudicotyledons and monocotyledons and Asteraceae, Fabaceae and Poaceae. Links between recurrent suites of ‘soft’ traits and ‘hard’ traits: The validity of PCA axis 1 as a key predictor of resource capture and utilization was tested by comparisons between this axis and values of more rigorously established predictors (‘hard’ traits) for the floras of Argentina and England. PCA axis 1 was correlated with variation in relative growth rate, leaf nitrogen content, and litter decomposition rate. It also coincided with palatability to model generalist herbivores. Therefore, location on PCA axis 1 can be linked to major ecosystem processes in those habitats where the plants are dominant. Conclusion: We confirm the existence at the global scale of a major axis of evolutionary specialization, previously recognised in several local floras. This axis reflects a fundamental trade‐off between rapid acquisition of resources and conservation of resources within well‐protected tissues. These major trends of specialization were maintained across different environmental situations (including differences in the proximate causes of low productivity, i.e. drought or mineral nutrient deficiency). The trends were also consistent across floras and major phylogenetic groups, and were linked with traits directly relevant to ecosystem processes. 相似文献
999.
Rademaker JL Herbet H Starrenburg MJ Naser SM Gevers D Kelly WJ Hugenholtz J Swings J van Hylckama Vlieg JE 《Applied and environmental microbiology》2007,73(22):7128-7137
The diversity of a collection of 102 lactococcus isolates including 91 Lactococcus lactis isolates of dairy and nondairy origin was explored using partial small subunit rRNA gene sequence analysis and limited phenotypic analyses. A subset of 89 strains of L. lactis subsp. cremoris and L. lactis subsp. lactis isolates was further analyzed by (GTG)(5)-PCR fingerprinting and a novel multilocus sequence analysis (MLSA) scheme. Two major genomic lineages within L. lactis were found. The L. lactis subsp. cremoris type-strain-like genotype lineage included both L. lactis subsp. cremoris and L. lactis subsp. lactis isolates. The other major lineage, with a L. lactis subsp. lactis type-strain-like genotype, comprised L. lactis subsp. lactis isolates only. A novel third genomic lineage represented two L. lactis subsp. lactis isolates of nondairy origin. The genomic lineages deviate from the subspecific classification of L. lactis that is based on a few phenotypic traits only. MLSA of six partial genes (atpA, encoding ATP synthase alpha subunit; pheS, encoding phenylalanine tRNA synthetase; rpoA, encoding RNA polymerase alpha chain; bcaT, encoding branched chain amino acid aminotransferase; pepN, encoding aminopeptidase N; and pepX, encoding X-prolyl dipeptidyl peptidase) revealed 363 polymorphic sites (total length, 1,970 bases) among 89 L. lactis subsp. cremoris and L. lactis subsp. lactis isolates with unique sequence types for most isolates. This allowed high-resolution cluster analysis in which dairy isolates form subclusters of limited diversity within the genomic lineages. The pheS DNA sequence analysis yielded two genetic groups dissimilar to the other genotyping analysis-based lineages, indicating a disparate acquisition route for this gene. 相似文献
1000.
Pandya GA Holmes MH Sunkara S Sparks A Bai Y Verratti K Saeed K Venepally P Jarrahi B Fleischmann RD Peterson SN 《Nucleic acids research》2007,35(21):e148
DNA resequencing arrays enable rapid acquisition of high-quality sequence data. This technology represents a promising platform for rapid high-resolution genotyping of microorganisms. Traditional array-based resequencing methods have relied on the use of specific PCR-amplified fragments from the query samples as hybridization targets. While this specificity in the target DNA population reduces the potential for artifacts caused by cross-hybridization, the subsampling of the query genome limits the sequence coverage that can be obtained and therefore reduces the technique's resolution as a genotyping method. We have developed and validated an Affymetrix Inc. GeneChip(R) array-based, whole-genome resequencing platform for Francisella tularensis, the causative agent of tularemia. A set of bioinformatic filters that targeted systematic base-calling errors caused by cross-hybridization between the whole-genome sample and the array probes and by deletions in the sample DNA relative to the chip reference sequence were developed. Our approach eliminated 91% of the false-positive single-nucleotide polymorphism calls identified in the SCHU S4 query sample, at the cost of 10.7% of the true positives, yielding a total base-calling accuracy of 99.992%. 相似文献