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The authors examined the possible role of HPL in the onset of labour. The HPL level of the maternal vein, the umbilical cord vein and artery was compared in vaginal mature (n = 16) and premature (n = 52) deliveries. The HPL concentration was also examined in mature (n = 18) and premature (n = 18) deliveries performed by caesarean section prior to the onset of labour. The results showed that: the serum HPL level in the maternal vein, the umbilical cord vein and artery was lower during the 33rd-36th and the 40th weeks in cases of vaginal delivery compared to elective caesarean section; The artery/vein ratio decreases during labour (A/V X 100 value), indicating that HPL metabolism in the fetus decreases during regular labour pains; The onset of premature labour and delivery was associated with lower HPL levels compared to normal pregnancy. The authors assume that the lower HPL level found in cases of vaginal delivery may be due to reduced placental perfusion, but they do not exclude the possible association of lower HPL concentrations in cases of premature delivery.  相似文献   
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Calciphylaxis – a topical overview   总被引:3,自引:0,他引:3  
'Calciphylaxis', a calcification syndrome associated with ischaemic cutaneous necrosis, is acquired naturally in humans in disease states. It is a life and limb-threatening complication, usually observed in patients with renal disease and secondary hyperparathyroidism, but known to occur in the absence of renal or parathyroid disease. The reported mortality rate, which ranges from 60-80%, relates to wound infection, sepsis and organ failure. It is a small-vessel vasculopathy, which is estimated to occur in about 4% of haemodialysis patients. Clinically, violaceous, reticulate areas of cutaneous necrosis and eschar may be evident, particularly in the extremities. In addition to the clinical picture, a raised calcium phosphorous product, an elevated parathyroid hormone level, radiographic evidence of vessel and soft-tissue calcification and the finding of mural calcification affecting small arteries and arterioles on histopathology help to confirm the diagnosis of this entity which generally has a poor prognosis. A high index of suspicion and an active multidisciplinary management approach, with rigorous attention to wound care and prevention of sepsis, are vital in the management of these patients. In this overview, we discuss the pathophysiology, clinical features and associations, risk factors, diagnosis and management issues relating to calciphylaxis.  相似文献   
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The dominant cone-rod dystrophy gene CORD6 has previously been mapped to within an 8 cM interval on chromosome 17p12-p13. The retinal- specific guanylate cyclase gene (RETGC-1), which maps to within this genetic interval and previously was implicated in Leber's congenital amaurosis, was screened for mutations within this family and in a panel of small families and individuals with various cone and cone- rod dystrophy phenotypes. A missense mutation (E837D) was identified in affected members of the CORD6 family, as well as a second missense mutation (R838C) in three other families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene to be implicated in cone-rod dystrophy and this is the first report of dominant mutations in this gene.   相似文献   
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The effects of different molecular weights of hyaluronic acid (HA), a major component of extracellular matrix, on gap junctional intercellular communication (GJIC) in normal human dermal fibroblasts (NHDF cells) were investigated. NHDF cells were cultured for 4 days with different molecular weights of HA and then the extent of GJIC was assessed by the scrape-loading dye transfer method, using Lucifer yellow. The area of dye transfer was greater in the dishes coated with HA than in those to which HA was added. Thus, NHDF cells cultured on surfaces coated with high molecular weight (HMW) HA (MW, 800 kDa) showed greatly enhanced GJIC. Furthermore, another aim of this study was to evaluate the effects of different molecular weights of HA on the production of FGF-2 and KGF, because both are important cytokines produced by NHDF cells. When FGF-2 and KGF cultured levels of cell extracts and media were determined by ELISA, both levels were significantly enhanced when cells were grown on plates coated with HMW HA. This finding indicated that the function of gap junction channels in NHDF cells grown on plates coated with HMW HA may promote the biosynthesis of growth factors such as FGF-2 and KGF.  相似文献   
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Lack of expression of the fragile X mental retardation protein (FMRP) results in mental retardation and macroorchidism, seen as the major pathological symptoms in fragile X patients. FMRP is a cytoplasmic RNA- binding protein which cosediments with the 60S ribosomal subunit. Recently, two proteins homologous to FMRP were discovered: FXR1 and FXR2. These novel proteins interact with FMRP and with each other and they are also associated with the 60S ribosomal subunit. Here, we studied the expression pattern of the three proteins in brain and testis by immunohistochemistry. In adult brain, FMR1, FXR1 and FXR2 proteins are coexpressed in the cytoplasm of specific differentiated neurons only. However, we observed a different expression pattern in fetal brain as well as in adult and fetal testis, suggesting independent functions for the three proteins in those tissues during embryonic development and adult life.   相似文献   
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IntroductionThe introduction of effective, evidence‐based approaches to centredness in health care is hindered by the fact that research results are not easily accessible. This is partly due to the large volume of publications available and because the field is closely linked to and in some ways encompasses adjoining fields of research, for example, shared decision making and narrative medicine. In an attempt to survey the field of centredness in health care, a systematic overview of reviews was conducted with the purpose of illuminating how centredness in health care is presented in current reviews.MethodsSearches for relevant reviews were conducted in the databases PubMed, Scopus, Cinahl, PsychINFO, Web of Science and EMBASE using terms connected to centredness in health care. Filters specific to review studies of all types and for inclusion of only English language results as well as a time frame of January 2017–December 2018, were applied.ResultsThe search strategy identified 3697 unique reviews, of which 31 were included in the study. The synthesis of the results from the 31 reviews identified three interrelated main themes: Attributes of centredness (what centredness is), Translation from theory into practice (how centredness is done) and Evaluation of effects (possible ways of measuring effects of centredness). Three main attributes of centeredness found were: being unique, being heard and shared responsibility. Aspects involved in translating theory into practice were sufficient prerequisites, strategies for action and tools used in safeguarding practice. Further, a variety and breadth of measures of effects were found in the included reviews.ConclusionsOur synthesis demonstrates that current synthesized research literature on centredness in health care is broad, as it focuses both on explorations of the conceptual basis and the practice, as well as measures of effects. This study provides an understanding of the commonalities identified in the reviews on centredness in healthcare overall, ranging from theory to practice and from practice to evaluation.Patient or Public ContributionPatient representatives were involved during the initiation of the project and in decisions about its focus, although no patient or public representatives made direct contributions to the review process.  相似文献   
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Look  AT; Peiper  SC; Douglass  EC; Trent  JM; Sherr  CJ 《Blood》1986,67(3):637-645
Spontaneous amplification of genes encoding two different human myeloid surface antigens was observed after DNA-mediated gene transfer of cellular DNA from the human myeloid cell line HL-60 into NIH-3T3 mouse fibroblasts. Transformed recipient cells with highly amplified expression of either of two donor membrane polypeptides, gp150 or p67, were isolated with a fluorescence-activated cell sorter (FACS), using monoclonal antibodies specific for human myeloid cells. Immunoprecipitation of enzymatically radioiodinated polypeptides from the surface of transformed NIH-3T3 cells confirmed that expression of these proteins was amplified tenfold to 20-fold in comparison to their expression on human myeloid cell lines. The cellular DNA of cloned secondary and tertiary transformants expressing high levels of gp150 and p67 contained amplified sets of DNA restriction fragments that hybridized with human repetitive DNA sequences. Cytogenetic analysis of subclones overexpressing gp150 revealed extrachromosomal double minutes (DMs), whose presence correlated with the unstable expression of the membrane polypeptide. Human sequences in gp150-positive clones did not localize to chromosomes, consistent with their association with extrachromosomal DMs. By contrast, p67-positive subclones stably expressed the antigen, and in situ hybridization to metaphase spreads demonstrated that amplified human DNA sequences were integrated into a specific marker chromosome. Cytogenetic analysis of the parental NIH- 3T3 subclone used in these studies disclosed DMs in a low percentage of metaphases, suggesting that the recipient cells have a propensity for amplifying donor DNA.  相似文献   
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