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11.
S. Stewart-Brown R. Surender J. Bradlow A. Coulter H. Doll 《BMJ (Clinical research ed.)》1995,311(7019):1543-1547
OBJECTIVES--To observe changes in prescribing practice that occurred after the introduction of fundholding in first wave practices and to contrast these with changes occurring in similar non-fundholding practices. DESIGN--Prospective observational study. SETTING--Oxford region fundholding study. SUBJECTS--Eight first wave fundholding practices and five practices that were not interested in fundholding in 1990-1, which were similar in terms of practice size, training status, locality, and urban rural mix. Three of the fundholding and none of the non-fundholding practices were dispensing practices. MAIN OUTCOME MEASURES--Changes in prescribing practice as measured by net cost per prescribing unit, cost per item, number of items prescribed, and substitution rates for generic drugs three years after the introduction of fundholding. Data for fundholding practices were analysed separately according to whether they were dispensing or non-dispensing practices. RESULTS--Prescribing costs rose by a third or more in all types of practice. The patterns of change observed in this cohort after one year of fundholding were reversed. No evidence existed that fundholding had controlled prescribing costs among non-dispensing fundholders; costs among dispensing fundholders rose least, but the differences were small compared with the overall increase in costs. CONCLUSIONS--Early reports of the effectiveness of fundholding in curbing prescribing costs have not been confirmed in this longer term study. 相似文献
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Serum titers to egg yolk were induced in 6 rabbits by intravaginal deposition of an egg-yolk citrate extender used for artificial insemination of cattle. There was no effect of the low serum titers to egg yolk on fertility of the inseminated rabbits. Titers to egg-yolk semen extender were found in 3% of 59 cows of normal fertility compared to 29% of 14 repeat breeder cows of low fertility, all previously inseminated with semen diluted with egg yolk-citrate extender. Four of 6 cervical mucus samples (67%) from the repeat breeder cows had high titers to egg yolk, but only one also had a positive titer in blood serum. 相似文献
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M Ballif P Harino S Ley M Coscolla S Niemann R Carter C Coulter S Borrell P Siba S Phuanukoonnon S Gagneux HP Beck 《BMC microbiology》2012,12(1):191-5
ABSTRACT: BACKGROUND: Monitoring drug resistance in Mycobacterium tuberculosis is essential to curb the spread of tuberculosis (TB). Unfortunately, drug susceptibility testing is currently not available in Papua New Guinea (PNG) and that impairs TB control in this country. We report for the first time M. tuberculosis mutations associated with resistance to first and second-line anti-TB drugs in Madang, PNG. A molecular cluster analysis was performed to identify M. tuberculosis transmission in that region. RESULTS: Phenotypic drug susceptibility tests showed 15.7% resistance to at least one drug and 5.2% multidrug resistant (MDR) TB. Rifampicin resistant strains had the rpoB mutations D516F, D516Y or S531L; isoniazid resistant strains had the mutations katG S315T or inhA promoter C15T; streptomycin resistant strains had the mutations rpsL K43R, K88Q, K88R), rrs A514C or gidB V77G. The molecular cluster analysis indicated evidence for transmission of resistant strain. CONCLUSIONS: We observed a substantial rate of MDR-TB in the Madang area of PNG associated with mutations in specific genes. A close monitoring of drug resistance is therefore urgently required, particularly in the presence of drug-resistant M. tuberculosis transmission. In the absence of phenotypic drug susceptibility testing in PNG, molecular assays for drug resistance monitoring would be of advantage. 相似文献
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J R Coulter 《Journal of bacteriology》1966,92(6):1655-1662
Coulter, John R. (Institute of Medical and Veterinary Science, Adelaide, Australia). Production, purification, and composition of staphyloccocal alpha toxin. J. Bacteriol. 92:1655-1662. 1966-Pure staphylococcal alpha toxin has been prepared in quantities suitable for chemical, biological, and clinical characterization. Purification was achieved by acid-methanol precipitation, chromatography on G100 Sephadex, and electrophoresis in G100 Sephadex. We recovered 25% of the crude toxin in pure form, a yield of 12 mg/liter of crude culture supernatant fluid. The pure material gave a single line on gel diffusion and on immunoelectrophoresis and gave a single symmetrical peak in the ultracentrifuge. The alpha toxin was highly unstable, with a half-life of 3 days at 0 C (pH 7.8); solutions of it could not be frozen, and we found no method to stabilize it. On standing, a thready precipitate appeared; it was inactive against rabbit red cells, was not lethal to rabbits, but was able to elicit specific anti-alpha antibody production in the rabbit. There is evidence that alpha toxin is an associating molecule, with a mean sedimentation coefficient of approximately 3.0 and a molecular weight of approximately 30,000. The lowest molecular weight, found by equilibrium ultracentrifugation, was 21,200 +/- 400. The amino acid composition was determined, and the high positive charge was explained by the presence of lysine, arginine, and histidine, and by amination of the aspartic and glutamic acid residues. Histidine and arginine were shown to be N-terminal amino acids, a fact which suggests the presence of two polypeptide chains. No carbohydrate was present. The ultraviolet absorption spectrum showed a maximum at 274.5 mmu, a minimum at 251.5 mmu, and a shoulder at 292 mmu. The toxin was without proteolytic or phospholipase activity, and its highly specific action on cell membranes still remains unexplained. 相似文献
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Timothy W. Yu Maria H. Chahrour Michael E. Coulter Sarn Jiralerspong Kazuko Okamura-Ikeda Bulent Ataman Klaus Schmitz-Abe David A. Harmin Mazhar Adli Athar N. Malik Alissa M. D’Gama Elaine T. Lim Stephan J. Sanders Ganesh H. Mochida Jennifer N. Partlow Christine M. Sunu Jillian M. Felie Jacqueline Rodriguez Christopher A. Walsh 《Neuron》2013,77(2):259-273
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Paul Aia Margaret Kal Evelyn Lavu Lucy N. John Karen Johnson Chris Coulter Julia Ershova Olga Tosas Matteo Zignol Shalala Ahmadova Tauhid Islam 《PloS one》2016,11(3)