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51.
Altered lymphocyte responses and cytokine production in mice deficient in the X-linked lymphoproliferative disease gene SH2D1A/DSHP/SAP 下载免费PDF全文
Czar MJ Kersh EN Mijares LA Lanier G Lewis J Yap G Chen A Sher A Duckett CS Ahmed R Schwartzberg PL 《Proceedings of the National Academy of Sciences of the United States of America》2001,98(13):7449-7454
We have introduced a targeted mutation in SH2D1A/DSHP/SAP, the gene responsible for the human genetic disorder X-linked lymphoproliferative disease (XLP). SLAM-associated protein (SAP)-deficient mice had normal lymphocyte development, but on challenge with infectious agents, recapitulated features of XLP. Infection of SAP- mice with lymphocyte choriomeningitis virus (LCMV) or Toxoplasma gondii was associated with increased T cell activation and IFN-gamma production, as well as a reduction of Ig-secreting cells. Anti-CD3-stimulated splenocytes from uninfected SAP- mice produced increased IFN-gamma and decreased IL-4, findings supported by decreased serum IgE levels in vivo. The Th1 skewing of these animals suggests that cytokine misregulation may contribute to phenotypes associated with mutation of SH2D1A/SAP. 相似文献
52.
Sher G Keskintepe L Keskintepe M Ginsburg M Maassarani G Yakut T Baltaci V Kotze D Unsal E 《Fertility and sterility》2007,87(5):1033-1040
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HLA-G is believed to play a pivotal role in the immunoprotection of the semiallogenic embryo. Its expression during pre- and early implantation is correlated with the cleavage rate of the embryo. Studies in congenic mice have revealed that mRNA of both the maternal and paternal haplotypes are present in zygotes and in embryos at all stages of development. 相似文献
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Multiple displacement amplification (MDA) renders an increased quantity of genomic DNA available for comparative genomic hybridization (CGH), enabling it to be used to identify genomic imbalances in human blastomeres. The karyotypic lineage of 57 blastocysts derived from 11 ovum donors following ovarian stimulation was examined. CGH was performed on all first polar bodies, and linearly on corresponding second polar bodies and blastomeres. A diploid karyotype was propagated from the prefertilized oocyte to the embryo in 25 (44%) sets of analyses. In 32/57 sets (56%), aneuploidy was detected in the post-fertilized zygotes/embryos and in nine (28%) of such cases the aneuploidy was 'chaotic' (> or =3 chromosomes). In 4/57 cases (7%) mitotic aneuploidy was observed. CGH and fluorescence in-situ hybridization (FISH) were concurrently performed on two blastomeres removed from each of 44 embryos obtained from four patients. In 43 (98%) of these embryos there was a direct karyotypic correlation between nine-probe commercial FISH and CGH. CGH identified > or =15% more chromosomal abnormalities than through FISH alone. The linear propagation using MDA-CGH, of the same karyotypic abnormalities that affected the oocyte of origin, in the corresponding embryos, coupled with the fact that CGH confirmed the aneuploidies identified through FISH, validates the accuracy and reliability of CGH technology. 相似文献
55.
Tayyaba Kokab Afzal Shah Jan Nisar Muhammad Naeem Ashiq M. Abdullah Khan Sher Bahadar Khan Esraa M. Bakhsh 《RSC advances》2021,11(57):35783
Phenolic pollutants are highly toxic and persistent in the environment. Their efficient detection is a pressing social demand. In this regard we introduce a novel ultrasensitive electroanalytical platform for the individual and synchronized detection of three phenolic isomers commonly known as hydroquinone (HQ), resorcinol (RC), and catechol (CC). The sensing device consists of a glassy carbon electrode (GCE) modified with functionalized carbon nanotubes (fCNTs) and gold–silver (Au–Ag NPs) bimetallic nanoparticles. The sandwiched scaffold represented as fCNTs/Au–Ag NPs/fCNTs/GCE efficiently senses HQ, RC, and CC with detection limits of 28.6 fM, 36.5 fM and 42.8 fM respectively. The designed sensor is more promising than reported sensors for phenolic toxins in the context of high sensitivity, selectivity, and rapid responsiveness. The designed sensor also shows the qualities of stability, reproducibility, reliability, and selective recognition capacity for target analytes in multiple real water samples. Moreover, computational calculations explain the function of the electrode modifier in facilitating charge transfer between the transducer and analytes.Phenolic pollutants are highly toxic and persistent in the environment. 相似文献
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BACKGROUND: The sentinel node biopsy concept has been gaining support in the head and neck cancer literature during only the last few years, and several pilot studies have been published. This procedure aims to avoid unnecessary treatment to the clinically negative neck by identifying the patients with occult neck disease. METHODS: We performed a systematic review and a diagnostic meta-analysis of all published literature regarding sentinel node biopsies in head and neck cancer until December 2003 using established guidelines. Using the pooled sensitivity rates obtained from the meta-analysis and treatment outcomes from published literature, we created a decision analysis model to identify the treatment arm with better payoffs. RESULTS: A total of 301 patients with oral cavity primary tumors and 46 patients with oropharyngeal primary tumors from 19 articles were included for the meta-analysis. The pooled sensitivity result using the random effects model was 0.926 (95% confidence interval, 0.852-0.964). The cumulative payoff for the sentinel node biopsy arm was lower than that for the elective node dissection arm by about 1%. The payoffs were assigned for the recurrence and mortality rates only and did not take into account the morbidity caused by the procedures. CONCLUSIONS: The sentinel node biopsy procedure has shown high sensitivity rates in pilot studies for oral and oropharyngeal squamous cell cancer across the globe and is reliable and reproducible. This study provides a firm evidence base for forthcoming trials on the role of sentinel node biopsy in head and neck cancer. 相似文献
58.
Sidra Ishaque Taimur Saleem Waris Qidwai 《BMC complementary and alternative medicine》2009,9(1):32-17
Background
Gemstones have been in use as part of alternative and complementary medicine for years. However, our understanding of the perceived healing powers of gemstones is limited. An extensive literature search revealed that there is a dearth of validated information on this subject. This study was therefore undertaken to explore the various aspects of the knowledge, attitudes, and practices of the public towards gemstone therapeutics. 相似文献59.
Muhammad Rizwan Khan Taimur Saleem Tanveer Ul Haq Kanwal Aftab 《Hepatobiliary & Pancreatic Diseases International》2011,(1)
BACKGROUND:Focal nodular hyperplasia,a benign hepatic tumor,is usually asymptomatic.However,rarely the entity can cause symptoms,mandating intervention. METHOD:We present a case of focal nodular hyperplasia of the liver,which caused a considerable diagnostic dilemma due to its atypical presentation. RESULTS:A 29-year-old woman presented with a 15-year history of a progressively increasing mass in the right upper quadrant which was associated with pain and emesis. Examination showed a firm,mobile mass palpab... 相似文献
60.