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11.
WIF1, a component of the Wnt pathway, is down-regulated in prostate, breast, lung, and bladder cancer 总被引:19,自引:0,他引:19
12.
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14.
DNA fingerprinting of isolates of Staphylococcus aureus from newborns and their contacts 总被引:2,自引:5,他引:2
Y Tveten B E Kristiansen E Ask A Jenkins T Hofstad 《Journal of clinical microbiology》1991,29(6):1100-1105
During a study on the epidemiology of Staphylococcus aureus colonization in newborns, mothers, and hospital staff, S. aureus was isolated from 536 of 1,945 specimens. Ninety-three isolates of S. aureus from the three groups of individuals were included in a study to evaluate the potential of DNA fingerprinting for strain differentiation. The 93 isolates were also phage typed and their plasmid profiles were analyzed. Cleavage of DNA with BamHI resulted in 13 different DNA restriction endonuclease band patterns (DNA REBPs), one of which consisted of eight isolates whose DNA was not cleaved with BamHI. The DNAs from these eight isolates were easily cleaved with HindIII. The different DNA REBPs were stable both during in vitro and in vivo growth and allowed strain differentiation within phage groups or types. We could not show any strong association between DNA REBP classes, phage types or groups, and plasmid profiles. Of the 93 isolates, 27 (29.0%) could not be phage typed and 12 (12.9%) lacked plasmids. We therefore conclude that DNA fingerprinting is a powerful tool, in addition to phage typing and plasmid profile analysis, for strain differentiation of S. aureus. 相似文献
15.
Kristiansen OP Karlsen AE Larsen ZM Johannesen J Pociot F Mandrup-Poulsen T;Danish IDDM Epidemiology Genetics Group Danish Study Group of IDDM in Childhood 《Scandinavian journal of immunology》2004,59(6):582-591
CD4 is a candidate gene in autoimmune diseases, including Type 1 diabetes mellitus (T1DM), because the CD4 receptor is crucial for appropriate antigen responses of CD4(+) T cells. We previously found linkage between a CD4-1188(TTTTC)(5-14) promoter polymorphism and T1DM. In the present study, we screened the human CD4 promoter for mutations and identified three frequent single nucleotide polymorphisms (SNPs): CD4-181C/G, CD4-521C/G and CD4-1050T/C. The SNPs are in strong linkage disequilibrium (LD) and association with the CD4-1188(TTTTC)(5-14) alleles, and we observed nine CD4 promoter haplotypes, of which four are frequent. We genotyped the SNPs in 253 Danish T1DM families (1129 individuals) and found evidence for linkage and association of a CD4 (A4(-1188)T(-1050)G(-521)C(-181)) haplotype to T1DM. In reporter studies, we show that (1) the T1DM-associated CD4 haplotype encodes high constitutive promoter activity and (2) the CD4-181G variant encodes higher stimulated promoter activity than the CD4-181C variant. This difference is in part neutralized in the frequently occurring CD4 promoter haplotypes by the more upstream genetic variants. Thus, we report functional impact of a novel CD4-181C/G SNP on stimulated CD4 promoter activity and the identification of a novel CD4 haplotype with high constitutive promoter activity that is linked and associated with T1DM. 相似文献
16.
Smoking and female infertility: a systematic review and meta-analysis 总被引:11,自引:10,他引:11
The high prevalence of smoking among women in their reproductive years
continues to be a matter of concern. The negative effects of smoking on
general health are well known, but smoking may also affect fertility. The
objective of the present study was to perform a systematic review of the
literature to determine whether there is an association between smoking and
risk of infertility in women of reproductive age, and to assess the size of
this effect. In the 12 studies used for this meta- analysis, the overall
value of the odds ratio (OR) for risk of infertility in women smokers
versus non-smokers was 1.60 [95% confidence interval (CI) 1.34-1.91].
Studies of subfertile women undergoing in-vitro fertilization (IVF)
treatment also show a reduction in fecundity among women smokers. A
meta-analysis of nine studies found an OR of 0.66 (95% CI 0.49-0.88) for
pregnancies per number of IVF- treated cycles in smokers versus
non-smokers. Despite the potential limitations of meta-analyses of
observational studies, the evidence presented in this review is compelling
because of the consistency of effect across different study designs, sample
size and types of outcome. However, continued reassurance is needed that
the calculated overall effect is not in fact due to confounding variables.
相似文献
17.
Positional cloning of the gene for X-linked retinitis pigmentosa 3: homology with the guanine-nucleotide-exchange factor RCC1 总被引:6,自引:7,他引:6
Roepman R; van Duijnhoven G; Rosenberg T; Pinckers AJ; Bleeker-Wagemakers LM; Bergen AA; Post J; Beck A; Reinhardt R; Ropers HH; Cremers FP; Berger W 《Human molecular genetics》1996,5(7):1035-1041
The gene for retinitis pigmentosa 3 (RP3), the most frequent form of X-
linked RP (XLRP), has been mapped previously to a chromosome interval of
less than 1000 kbp between the DXS1110 marker and the OTC locus at
Xp21.1-p11.4. Employing a novel technique, YAC Representation Hybridization
(YRH)', we have recently identified a small XLRP associated microdeletion
in this interval, as well as several putative exons including the 3' end of
a gene that was truncated by the deletion. cDNA library screening and
sequencing of a cosmid centromeric to the deletion has now enabled us to
identify numerous additional exons and to detect several point mutations in
patients with XLRP. The predicted gene product shows homology to RCC1, the
guanine-nucleotide- exchange factor (GEF) of the Ras-like GTPase Ran. Our
findings suggest that we have cloned the long-sought RP3 gene, and that it
may encode the GEF of a retina-specific GTP-binding protein.
相似文献
18.
Lundberg S; Rasmussen C; Berg AA; Lindblom B 《Human reproduction (Oxford, England)》1998,13(6):1490-1492
Falloposcopy is a transvaginal microendoscopic technique to explore the
human Fallopian tube from the uterotubal ostium to the fimbrial end.
Falloposcopy provides a unique possibility to visualize endotubal disease
and may be used therapeutically for removal of debris and for cutting down
filmy intraluminal adhesions. To assess the clinical performance of
falloposcopy as part of an infertility investigation, a total of 43 women
scheduled for laparoscopy as part of an investigation of infertility had a
falloposcopy performed in conjunction with the laparoscopy. All women were
investigated at Danderyd Hospital, Stockholm and Akademiska Hospital,
Uppsala, during 1995 and 1996. Images from the endosalpinx were obtained in
26 of 43 women (60.5%). In 10 women (23.3%), it was possible to obtain
images from both tubes. No images were of sufficient quality to describe
the entire tubal mucosa in detail. Falloposcopy represents a unique tool
for visualization of endotubal disease and may provide a valuable
instrument for in-vivo exploration of tubal physiology. However, certain
technical problems limit the usefulness of this method in routine clinical
practice. These technical problems have to be solved before falloposcopy
can achieve a central position in investigation and treatment of tubal
disease.
相似文献
19.
Knudsen TB Kledal TN Andersen O Eugen-Olsen J Kristiansen TB 《Scandinavian journal of immunology》2003,58(3):277-284
The recent identification of a novel clinical entity, the severe acute respiratory syndrome (SARS), the rapid subsequent spread and case fatality rates of 14-15% have prompted a massive international collaborative investigation facilitated by a network of laboratories established by the World Health Organization (WHO). As SARS has the potential of becoming the first pandemic of the new millennium, a global warning by the WHO was issued on 12 March 2003. The disease, which is believed to have its origin in the Chinese Guangdong province, spread from Hong Kong via international airports to its current worldwide distribution. The concerted efforts of a globally united scientific community have led to the independent isolation and identification of a novel coronavirus from SARS patients by several groups. The extraordinarily rapid isolation of a causative agent of this newly emerged infectious disease constitutes an unprecedented scientific achievement. The main scope of the article is to provide the clinician with an overview of the natural history, epidemiology and clinical characteristics of SARS. On the basis of the recently published viral genome and structural features common to the members of the coronavirus family, a model for host cell-virus interaction and possible targets for antiviral drugs are presented. The epidemiological consequences of introducing a novel pathogen in a previously unexposed population and the origin and evolution of a new and more pathogenic strain of coronavirus are discussed. 相似文献
20.
Comparison of the human and mouse genes encoding the telomeric protein, TRF1: chromosomal localization, expression and conserved protein domains 总被引:11,自引:0,他引:11