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51.
WATSON RGP; McMILLAN SA; DICKEY W; BIGGART JD; PORTER KG 《QJM : monthly journal of the Association of Physicians》1992,84(2):713-718
Eighteen patients with a variety of non-gastrointestinal symptomswere incidentally found to have circulating antireticulin antibodyand on subsequent testing were also positive for antigliadinantibody. They prospectively underwent jejunal biopsy to determinewhether or not they had coeliac disease. Their age range was21–79 years (mean 42 years). Enteropathy was present in13 (72 per cent) and was always associated with circulatingIgA antigliadin antibody. Enteropathy was not present in thefive cases who had only IgG antibody. Clinical improvement occurredin eight of 11 patients who complied with a gluten-free dietand was paralleled by an improvement in the mucosal histologyin seven of eight who were re-biopsied. The most remarkablecases were two patients who presented with severe debility andno apparent haematological or biochemical abnormalities, andwho subsequently made a dramatic recovery on a gluten-free diet.It is concluded that antireticulin antibody detected by routineautoantibody screening and confirmed to have IgA antigliadinantibody specificity is a useful indicator of an otherwise undiagnosedenteropathy. This serves to emphasize that the condition cansometimes be associated with atypical features and significantmorbidity. 相似文献
52.
Genetic mapping of the human homologue (T) of mouse T(Brachyury) and a search for allele association between human T and spina bifida 总被引:3,自引:0,他引:3
53.
Androgen receptor YAC transgenic mice carrying CAG 45 alleles show trinucleotide repeat instability 总被引:1,自引:15,他引:1
La Spada AR; Peterson KR; Meadows SA; McClain ME; Jeng G; Chmelar RS; Haugen HA; Chen K; Singer MJ; Moore D; Trask BJ; Fischbeck KH; Clegg CH; McKnight GS 《Human molecular genetics》1998,7(6):959-967
X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG
repeat expansion in the first exon of the androgen receptor (AR) gene.
Disease-associated alleles (37-66 CAGs) change in length when transmitted
from parents to offspring, with a significantly greater tendency to shift
size when inherited paternally. As transgenic mice carrying human AR cDNAs
with 45 and 66 CAG repeats do not display repeat instability, we attempted
to model trinucleotide repeat instability by generating transgenic mice
with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions
in their genomic context. Studies of independent lines of AR YAC transgenic
mice with CAG 45 alleles reveal intergenerational instability at an overall
rate of approximately 10%. We also find that the 45 CAG repeat tracts are
significantly more unstable with maternal transmission and as the
transmitting mother ages. Of all the CAG/CTG repeat transgenic mice
produced to date the AR YAC CAG 45 mice are unstable with the smallest
trinucleotide repeat mutations, suggesting that the length threshold for
repeat instability in the mouse may be lowered by including the appropriate
flanking human DNA sequences. By sequence-tagged site content analysis and
long range mapping we determined that one unstable transgenic line has
integrated an approximately 70 kb segment of the AR locus due to
fragmentation of the AR YAC. Identification of the cis - acting elements
that permit CAG tract instability and the trans -acting factors that
modulate repeat instability in the AR YAC CAG 45 mice may provide insights
into the molecular basis of trinucleotide repeat instability in humans.
相似文献
54.
It has previously been shown that monolayer cultures derived adherent cells (MDAC), apparently consisting of fibroblasts, macrophages, epithelioid cells, and fat cells, can support long-term stem cell proliferation in vitro. In the present study, the hematopoietic support capability of murine MDAC monolayers was confirmed and the cultured cells further characterized with respect to the following properties: esterase I activity, complement (C3) receptors, IgG (Fc) receptors, colony stimulating activity (csa) production, and collagen synthesis. The cultures were also examined immunohistochemically to localize fibronectin, laminin, and collagen synthesis and to identify the collagen subtypes synthesized. MDAC morphology was as described in previous studies, although fat cells were few in number. It was found that MDAC included some cells with esterase I activity and C3 receptors. Fc receptors were not, however, detected, nor did the cultures produce csa, indicating that mononuclear phagocytes were not present. MDAC synthesized collagen types I and III and also fibronectin. Staining for epithelial basement membrane proteins (collagen types IV and V and laminin) was negative. The results indicate that the vast majority of these cultured MDAC were fibroblasts. 相似文献
55.
The role of size, sequence and haplotype in the stability of FRAXA and FRAXE alleles during transmission 总被引:2,自引:5,他引:2
Murray A; Macpherson JN; Pound MC; Sharrock A; Youings SA; Dennis NR; McKechnie N; Linehan P; Morton NE; Jacobs PA 《Human molecular genetics》1997,6(2):173-184
Factors involved in the stability of trinucleotide repeats during
transmission were studied in 139 families in which a full mutation,
premutation or intermediate allele at either FRAXA or FRAXE was
segregating. The transmission of alleles at FRAXA, FRAXE and four
microsatellite loci were recorded for all individuals. Instability within
the minimal and common ranges (0-40 repeats for FRAXA, 0-30 repeats for
FRAXE) was extremely rare; only one example was observed, an increased in
size at FRAXA from 29 to 39 repeats. Four FRAXA and three FRAXE alleles in
the intermediate range (41-60) repeats for FRAXA, 31-60 for FRAXE) were
unstably transmitted. Instability was more frequent for FRAXA intermediate
alleles that had a tract of pure CGG greater than 37 although instability
only occurred in two of 13 such transmissions: the changes observed were
limited to only one or two repeats. Premutation FRAXA alleles over 100
repeats expanded to a full mutation during female transmission in 100% of
cases, in agreement with other published series. There was no clear
correlation between haplotype and probability of expansion of FRAXA
premutations. Instability at FRAXA or FRAXE was more often observed in
conjunction with a second instability at an independent locus suggesting
genomic instability as a possible mechanism by which at least some FRAXA
and FRAXE mutations arise.
相似文献
56.
Mehmet SA?LAM Serhat K?SEO?LU Mükerrem HAT?PO?LU Hac? Hasan ESEN Ekrem K?KSAL 《Journal of applied oral science : revista FOB》2015,23(1):33-41
Objectives
Sumac (Rhus coriaria L.) is widely used spice which has several properties such as antioxidant, anti-inflammatory and antimicrobial. The purpose of this animal study was to evaluate the effects of sumac extract on levels of receptor activator of nuclear factor-kappa B ligand (RANKL), osteoprotegerin (OPG) expression, serum oxidative status, and alveolar bone loss in experimental periodontitis.Material and Methods
Twenty-four Wistar rats were separated into three groups: non-ligated (NL, n=8), ligature only (LO, n=8), and ligature and treated with sumac extract (S, n=8) (20 mg/kg per day for 11 days). A 4/0 silk suture was placed around the mandibular right first molars subgingivally; after 11 days, the rats were sacrificed, and alveolar bone loss was histometrically measured. The detection of RANKL and OPG were immunohistochemically performed. Levels of serum total antioxidant status (TAS)/total oxidant status (TOS), and oxidative stress index (OSI) were also analyzed.Results
Alveolar bone loss was significantly greater in the LO group compared to the S and NL groups (p<0.05). The number of inflammatory cell infiltrate (ICI) and osteoclasts in the LO group was significantly higher than that of the NL and S groups (p<0.05). The number of osteoblasts in the LO and S groups was significantly higher than that of the NL group (p<0.05). There were significantly more RANKL-positive cells in the LO group than in the S and NL groups (p<0.05). OPG-positive cells were higher in S group than in LO and NL groups (p<0.05). TOS and OSI levels were significantly reduced in S group compared to LO group (P<0.05) and TAS levels were similar in S and NL group (p>0.05).Conclusions
The present study showed that systemic administration of sumac extract may reduce alveolar bone loss by affecting RANKL/OPG balance, TOS and OSI levels in periodontal disease in rats. 相似文献57.
输血和大多数临床治疗技术一样,存在着一定的风险,输血风险主要由免疫性输血风险和输血感染性风险两大类相关的安全问题。20世纪80年代开始,由于艾滋病的发现迫使输血相关的安全问题更进一步成为公众关注的焦点。随着输血用血医学的不断发展,在已经获得很好治疗效果的同时,如何更加科学的安全用血是挑战当今公共卫生事业发展的一项大课题。 相似文献
58.
实验动物资源是国家生命科学研究的重要科技资源。实验动物资源的共享和充分利用是生物科技创新的基础和保障。有效的共享机制和合理的共享方式是实现实验动物资源共享和充分利用的重要保障,是规范实验动物资源共享行为和确保共享安全的迫切需要。 相似文献
59.
60.