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991.
The authors used polymerase chain reaction to analyse 56 Slovenian cystic fibrosis (CF) chromosomes for the presence of delta F508 and eight other most frequent mutations located in exons 7,11 and 20 (R347P, R334W, G551D, R553X, S549RA, S549RT, S549I and S1255X) of the CF gene. We also determined the frequency of haplotypes associated with CF for six linked RFLP markers (MetD/TaqI, MetH/TaqI, XV-2c/TaqI, KM-19/PstI, MP6d9/MspI and J3.11/MspI) in 27 Slovenian CF families. delta F508 mutation was present in 55.4 percent of the CF chromosomes. No case of the other mutations were detected in the sample of tested CF chromosomes. A very high degree of association (0.88) has been found between DNA marker MetH and CF (as measured by the Yule's association coefficient) in our population. Using the RFLP markers XV-2c and KM-19, we found that 85% of delta F508 mutated chromosomes have a single 1 2 (B) haplotype, and that this haplotype is present on only 15.4 percent of CF chromosomes without this deletion.  相似文献   
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The Oral History and Literature of the Wolof People of Waalo, Northern Senegal. Samba Diop. Lewiston, Canada; Edwin Mellen Press, 1995. 389 pp.  相似文献   
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The muscle phase of Trichinella spiralis and of Trichinella sp. isolated in the Arctic was compared in experimental and wild animals. Reproductive capacity indices (RCI) of the Trichinella sp. isolate were significantly lower in laboratory rodents but were similar to T. spiralis in wild rodents. Sprague-Dawley rats were the most refractory to the Trichinella sp. isolate of all laboratory rodents. Outbred strains of mice were more susceptible to both T. spiralis and the Trichinella sp. isolate than inbred strains of mice. T. spiralis muscle larvae survived longer in mice and the survival of both T. spiralis and the Trichinella sp. isolate larvae was higher in female mice. While single pair interbreeding experiments showed reproductive isolation between T. spiralis and the Trichinella sp. isolate, multiple pair and transplant breeding experiments showed reproductive compatibility. Male and female infective larvae of T. spiralis and the Trichinella sp. isolate differed morphometrically, but a convergence in size of worms was observed after prolonged passages of the parasites in mice. Passaging history of the isolate and host species was found to have a significant effect on Trichinella morphology. It is proposed that the Trichinella sp. isolate is a physiological variant of T. spiralis and not a distinct species.  相似文献   
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We have used a quantitative titration assay for mixed lymphocyte interactions to determine the additivity of responses of rat lymphocyte populations to simultaneous stimulation with major histocompatibility complex alloantigens from pairs of apparently unrelated rat strains. Our inability to detect strict additive stimulation led us to investigate inclusion among allo-reactive lymphocyte populations. After specific depletion of reactivity to PVG by negative selection through an AO × PVG F1 hybrid rat, AO thoracic duct lymphocytes showed an asymmetrical loss of reactivity to the unrelated strains DA and F344. We suggest that this differential loss of reactivity probably reflects alloantigen sharing among rat strains which had been previously undetected using other less sensitive techniques for the quantitation of lymphocyte reactivity after specific depletion of allo-reactive cells.  相似文献   
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