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1.
Amino acid limited growth of starter cultures in milk 总被引:2,自引:0,他引:2
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A Jans E F Ippel P F Dijkstra J B Bijlsma 《Genetic counseling (Geneva, Switzerland)》1992,3(3):139-143
We report two sisters with mental retardation, coarse facial features, telecanthus, flat malar region, prominent lower lip, kyphoscoliosis, and tapering fingers. Although these patients' phenotypes showed considerable overlap with the Coffin-Lowry and the Atkin-Flaitz syndromes, their overall picture makes these diagnoses controversial. 相似文献
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Influence of temperature on the number of Legionella pneumophila in hot water systems 总被引:1,自引:1,他引:0
The occurrence of legionella in the hot water systems of two buildings (A and B) was investigated in relation to the water temperature. The peripheral parts of both hot water systems were found to be colonized by these organisms. A temperature of 60C in the hot water mains returning from the building eliminated legionellas from the mains as well as from the peripheral taps and showers. Legionellas could be isolated from taps, showers and the mains when the temperature in the return mains was kept at 54C. The hot water systems could not be completely decontaminated by raising the hot water temperature in the return mains to 70C combined with flushing all the taps and showers. It is suggested that failure to decontaminate the systems is due to dead ends in the pipeline network, which are not reached by the hot water and that these dead ends are the source for recolonization of the systems. 相似文献
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Maria A. Papathanasopoulos Francois Krier Anne-Marie Revol-Junelles Gerard Lefebvre Jean Pierre Le Caer Alexander von Holy John W. Hastings 《Current microbiology》1997,35(6):331-335
Leuconostoc (Lc.) mesenteroides TA33a produced three bacteriocins with different inhibitory activity spectra. Bacteriocins were purified by adsorption/desorption
from producer cells and reverse phase high-performance liquid chromatography. Leucocin C-TA33a, a novel bacteriocin with a
predicted molecular mass of 4598 Da, inhibited Listeria and other lactic acid bacteria (LAB). Leucocin B-TA33a has a predicted molecular mass of 3466 Da, with activity against Leuconostoc/Weissella (W.) strains, and appears similar to mesenterocin 52B and dextranicin 24, while leucocin A-TA33a, which also inhibited Listeria and other LAB strains, is identical to leucocin A-UAL 187. A survey of other known bacteriocin-producing Leuconostoc/Weissella strains for the presence of the three different bacteriocins revealed that production of leucocin A-, B- and C-type bacteriocins
was widespread. Lc. carnosum LA54a, W. paramesenteroides LA7a, and Lc. gelidum UAL 187-22 produced all three bacteriocins, whereas W. paramesenteroides OX and Lc. carnosum TA11a produced only leucocin A- and B-type bacteriocins.
Received: 11 April 1997 / Accepted: 10 June 1997 相似文献
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Summary 1)The transmission dynamics of the protozoan parasite Sarcocystis carnae (erná and Louková 1976) (Apicomplexa, Eimeroidea, Sarcocystidae) in natural populations were studied in the Lauwersmeerpolder in the northern Netherlands. This parasite needs two hosts to complete its life cycle; the common vole (Microtus arvalis) as its intermediate host and the kestrel (Falco tinnunculus) which preys on the vole, as its final host. 2) Seasonal variation in prevalence of infection in snap-trapped common voles was determined in two years, 1984 and 1985. It was found to be lowest in November (6% of the voles infected) and it increased gradually to a peak in May (33%). 3) Data collected in three successive kestrel breeding seasons (1983–85) revealed that voles in the kestrel summer diet are infected twice as frequently as those in snap-trap samples, 21% and 9% respectively. This difference (P<0.05, X2-test) suggests that the parasite influences its intermediate host behaviour in such a way that it enhances the probability of parasite transmission to the final host. 相似文献
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JoAnne S. Richards Gerard J. Hickey Shiuan Chen John E. Shively Peter F. Hall Dana Gaddy-Kurten Richard Kurten 《Steroids》1987,50(4-6):393-409
To determine the molecular basis for changes in aromatase (P450arom) activity in rat ovarian follicles and corpora lutea, seven clones for rat P450arom cDNA have been identified and isolated from a rat granulosa cell λgtll cDNA expression library using a 62 mer deoxyoligonucleotide probe (derived from an amino acid sequence of purified human placental aromatase) and a human placental P450arom cDNA probe. One of the rat P450arom cDNA clones contained an insert 1.2 kb in size. Both the human 1.8 kb cDNA and the rat 1.2 kb cDNA probes hybridized to a single species of P450arom mRNA that was 2.6 kb in size. Northern blot analysis revealed that corpora lutea isolated on day 15 of pregnancy contained high amounts of P450arom mRNA, whereas granulosa cells of antral follicles of hormonally primed, hypophysectomized rats (i.e., those from which mRNA was isolated to construct the cDNA library) contained only low amounts of P450arom mRNA. The lower amounts of P450arom in granulosa cells of preovulatory follicles in the estradiol-follicle-stimulating hormone primed hypophysectomized rats were unexpected because follicles incubated in medium containing testosterone substrate produce more estradiol than do corpora lutea isolated on day 15 of pregnancy and incubated under similar conditions. Additional studies will determine the hormonal events responsible for the elevated amounts and constitutive maintenance of P450arom mRNA and aromatase activity in luteal cells in vivo and in vitro. 相似文献