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51.
High Quality Independent From a Donor: Human Amniotic Fluid Derived Stem Cells—A Practical Analysis Based on 165 Clinical Cases 下载免费PDF全文
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Familial adenomatous polyposis (FAP) is a well-known hereditary condition characterised by alimentary system tumours. Tens
to thousands of polyps occur in the colon and rectum of the patients. There is a high heterogeneity with regard to the number
and time of the occurrence of polyps. The occurrence of FAP is associated with mutations in theAPC tumour suppressor gene, which was described in 1991. Since then, many studies have been done to analyse the distribution
of mutations in individual populations and to determine the function of the gene and a diagnostic approach to FAP. Here theAPC gene was studied with respect to the occurrence of small mutations and large rearrangements in 300 unrelated Polish FAP families.
Ninety-seven mutations were identified in 164 families. Out of these mutations, 80 were small mutations, including 58 small
mutations that were first identified in the Polish population (42 novel and 16 described previously). An increased frequency
of mutation c.3927_3931delAAAGA was observed in 10% of the Polish group. Seventeen large rearrangements were found in 29 families.
Out of those rearrangements, 8 repeat rearrangements occurred in 20 families. A problem in fast molecular diagnostics of FAP
is a high heterogeneity of mutations in theAPC gene. It seems that a multiplex ligation-dependent probe amplification test and searching for small mutations by the use
of screening methods at the 5’ end of exon 15 and exons 14, 9, 11, 13, 5, and 3, help to improve the molecular diagnostics
of FAP in Polish patients. 相似文献
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Fossøy F Moksnes A Røskaft E Antonov A Dyrcz A Moskat C Ranke PS Rutila J Vikan JR Stokke BG 《PloS one》2012,7(5):e36884
Sex allocation theory and empirical evidence both suggest that natural selection should favour maternal control of offspring sex ratio in relation to their ability to invest in the offspring. Generalist parasites constitute a particularly interesting group to test this theory as different females commonly utilize different host species showing large variation in provisioning ability. The common cuckoo (Cuculus canorus) is a generalist brood parasite that lays its eggs in the nest of many different passerine birds, but each female tends to specialize on one particular host species giving rise to highly specialized host races. The different host species show large variation in their ability to invest in the parasitic offspring, presenting an opportunity for female cuckoos to bias offspring sex ratio in relation to host species quality. Here, we investigate host-race specific sex allocation controlling for maternal identity in the common cuckoo. We found no evidence of any significant relationship between host race and sex ratio in one sympatric population harbouring three different host races, or in a total of five geographically separated populations. There was also no significant association between host quality, as determined by species-specific female host body mass, and cuckoo sex ratio. Finally, we found no significant relationship between individual cuckoo maternal quality, as determined by her egg volume, and sex ratio within each host race. We conclude that the generalist brood-parasitic common cuckoo show no significant sex-ratio bias in relation to host race and discuss this finding in light of gene flow and host adaptations. 相似文献
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When cells are briefly exposed to cis-diamminedichloroplatinum (II) before lysis in high sodium dodecyl sulfate-urea solutions, the high molecular-weight nucleic acids pelleted by ultracentrifugation contain an increased level of bound proteins when compared to a similar fraction from untreated cells. Subsequent shearing of the pelleted DNA followed by treatment with DNase permits electrophoretic and immunoblot analysis of the crosslinked proteins. In the present study such experiments were carried out with reference to nuclear envelope pore complex proteins in the differentiating L8 rat skeletal muscle cells. The results show that (i) whereas the major lamin proteins crosslinked to DNA in both myoblast and myotubes, lamin B is crosslinked to a greater extent to DNA in myotubes; (ii) a 62-kDa lectin-binding glycoprotein is apparently situated differently with respect to DNA in myotube nuclei; and (iii) the crosslinking pattern of the nuclear matrix proteins to DNA is qualitatively similar in myoblast and myotubes. In addition, lamin C′, a modified form of lamin C, not observed in intact nonmuscle cells previously [[31.] J. Biol. Chem. 260, 1895–1900], exists as a native component of the nuclear lamina in rat skeletal myotubes but not in myoblasts. These results point to significant structural alterations in the proteins of the nuclear lamina-pore complex during myogenesis. 相似文献
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Nowacki A Smiataczowa K Kasprzykowska R Dmochowska B Wiśniewski A 《Carbohydrate research》2002,337(3):265-272
Four isomers of methyl 2-deoxy-D-arabino-hexosides were isolated by HPLC as chromatographically homogeneous compounds. The rates of pyranoside isomerization (alpha(p) and beta(p)) at 40 degrees C and of furanoside isomerization (alpha(f) and beta(f)) at 26 degrees C were determined. A mechanism has been suggested for transformations taking place during isomerization of methyl 2-deoxy-D-arabino-hexosides in methanolic solution catalyzed with hydrogen chloride. 相似文献
58.
Wu C Li X Yuan W Chen G Kilian A Li J Xu C Li X Zhou DX Wang S Zhang Q 《The Plant journal : for cell and molecular biology》2003,35(3):418-427
Enhancer trapping has provided a powerful strategy for identifying novel genes and regulatory elements. In this study, we adopted an enhancer trap system, consisting of the GAL4/VP16-UAS elements with GUS as the reporter, to generate a trapping population of rice. Currently, 31 443 independent transformants were obtained from two cultivars using Agrobacterium-mediated T-DNA insertion. PCR tests and DNA blot hybridization showed that about 94% of the transformants contained T-DNA insertions. The transformants carried, on average, two copies of the T-DNA, and 42% of the transformants had single-copy insertions. Histochemical assays of approximately 1000 T0 plants revealed various patterns of the reporter gene expression, including expression in only one tissue, and simultaneously in two or more tissues. The expression pattern of the reporter gene in T1 families corresponded well with the T0 plants and segregated in a 3 : 1 Mendelian ratio in majority of the T1 families tested. The frequency of reporter gene expression in the enhancer trap lines was much higher than that in gene trap lines reported previously. Analysis of flanking sequences of T-DNA insertion sites from about 200 transformants showed that almost all the sequences had homology with the sequences in the rice genome databases. Morphologically conspicuous mutations were observed in about 7.5% of the 2679 T1 families that were field-tested, and segregation in more than one-third of the families fit the 3 : 1 ratio. It was concluded that GAL4/VP16-UAS elements provided a useful system for enhancer trap in rice. 相似文献
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X‐ray crystal structures of the pheromone‐binding domains of two quorum‐hindered transcription factors,YenR of Yersinia enterocolitica and CepR2 of Burkholderia cenocepacia 下载免费PDF全文