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21.
The majority of breast cancer research is conducted using established breast cancer cell lines as in vitro models. An alternative is to use cultures established from primary breast tumours. Here, we discuss the pros and cons of using both of these models in translational breast cancer research.  相似文献   
22.
The aim of this study was to investigate the time course of maternal allosensitization to fetal HLA antigens during normal human pregnancy and to explore mechanisms of suppression of anti-HLA alloantibodies. We found that the mother produces antibodies against some but not all of the mismatched HLA antigens of the fetus as early as the 8th week of pregnancy. These antibodies (Ab1), however, are often complexed with soluble HLA alloantigens and become detectable when immune complexes are dissociated. Soluble HLA antigens of fetal origin are present in the maternal circulation throughout the entire pregnancy beginning at 8 weeks. In some women the production of anti-anti-HLA antibodies (Ab2) became evident as early as the first trimester, while in others Ab2 was documented during the second or third trimester. Analysis of antibody specificity showed that some healthy primipara develop antibodies reactive with self HLA antigens. Although the allo- and autoantibody responses appear to be modulated by soluble HLA antigens, cyclic variations in the level of alloantibodies, as well as the mother's selective response to some, but not all, paternal HLA antigens, are best explained by the development of anti-idiotypic antibodies.  相似文献   
23.
A family is described in which 2 siblings born to healthy parents presented with abnormal facies, persistent diarrhoea, and early death. Exhaustive pathological and biochemical investigations failed to find a cause. The scalp hair of both babies had an abnormal amino-acid composition, and presented an appearance that was unique on scanning electron microscopical examination; this fact and the clinical picture probably represents a new syndrome.  相似文献   
24.
It is imperative to know the details of the anatomy of the nose before understanding any surgical procedure performed on the nose. The details presented in this article should help the experienced and the novice surgeon accomplish the difficult task of a rhinoplasty.  相似文献   
25.
Several studies of tumors have revealed substantial numbers of clonally expanded somatic mutations in mitochondrial DNA (mtDNA), not observed in adjacent intact tissues. These findings were interpreted as indicating the involvement of mtDNA mutations in tumorigenesis. Such comparisons, however, ignore an important confounding factor: the monoclonal origin of tumors as opposed to the highly polyclonal nature of normal tissues. Analysis of recently published data on the incidence of somatic mutations in nontumor monoclonal cells suggests that, contrary to the prevailing view, the process of tumorigenesis may be accompanied by active selection against detrimental mtDNA mutations.  相似文献   
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27.
The focus on quality of life issues in wound care has justly taken a far greater importance. With the acceptance that pain can be a major factor to the patient, and in particular, pain at dressing change comes the opportunity for avoidance and/or reduction strategies. Whilst pain has been associated with wound infection for millennia, it is only much more recently that this has received due attention from research and clinical practice. In this study, the nature of pain, changes in pain and pain associated with infection are the focal points. A Delphi approach, now a frequently used tool in wound care research, has been used to obtain expert opinion on these aspects of management.  相似文献   
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自美国国家骨髓库(NMDP)开展第一例无关供者移植以来,至今已有20年.NMDP目前的库容量已逾700万,已为6大洲提供了30 000多份无关供者造血干细胞.这一辉煌成就是美国国家骨髓库600多名工作人员共同努力的结果,同时也得益于广泛的国际合作,包括171个移植中心,73个供者中心,24个脐血库,97个骨髓采集中心,91个血液净化中心,26个HLA分型实验室和26个合作供者登记处.本文回顾了美国国家骨髓库的历史,阐述了20年来移植病人、移植物来源和预处理方案几方面的主要变化趋势.  相似文献   
30.
BACKGROUND: Chagas' disease, caused by the protozoan parasite Trypanosoma cruzi, is endemic to Latin America and may be transmitted in the United States via blood donated by infected immigrants. Blood- borne pathogens such as T. cruzi require supplemental testing for confirmation of seroreactivity. STUDY DESIGN AND METHODS: A study was undertaken to determine an optimal scheme for confirmation of seroreactivity in repeatedly reactive samples identified by the Chagas antibody enzyme immunoassay (EIA). The procedure for initial confirmation involves three purified antigens coated onto three separate polystyrene beads and uses an EIA format. If the sample is reactive with two of three or three of three antigens, it is confirmed as seroreactive. If none or one of three beads is reactive, the sample is indeterminate and subjected to a radioimmunoprecipitation assay (RIPA). The RIPA must demonstrate characteristic bands at 32, 34, and 90 kDa. RESULTS: When tested with sera from persons with potentially cross-reactive diseases (n = 39) or against a presumed negative population from southeast Wisconsin (n = 289), the confirmatory EIA had a specificity of 100 percent. Sensitivity was 100 percent (28/28) with xenodiagnosis-positive sera and 97.6 percent (80/82) with chagasic sera from Latin America. The RIPA showed a specificity of 100 percent in EIA- nonreactive samples (n = 100) and a sensitivity of 100 percent with both xenodiagnosis-positive (28/28) and chagasic (82/82) sera. CONCLUSION: The confirmatory EIA and the RIPA together provide a highly specific and sensitive means of confirming seroreactivity for antibodies to T. cruzi.  相似文献   
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