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41.
BACKGROUND: Many pregnant women experience anxiety while waiting for the results of diagnostic tests. Policies and practices intended to reduce this anxiety require evaluation. OBJECTIVES: To test the following two hypotheses: * That giving amniocentesis results out on a fixed date alters maternal anxiety during the waiting period, compared with a policy of telling parents that the result will be issued "when available" (i.e. variable date). * That issuing early results from a rapid molecular test alters maternal anxiety during the waiting period, compared with not receiving any results prior to the karyotype. The effects of the two interventions on anxiety 1 month after receiving karyotype results were also examined. DESIGN: A multicentre, randomised, controlled, open fixed sample, 2 x 2 factorial design trial, with equal randomisation. SETTING: The prenatal diagnosis clinics in 12 hospitals in England offering amniocentesis as a diagnostic test for Down's syndrome. SAMPLE: Two hundred and twenty-six women who had had an amniocentesis were randomised between June 2002 and July 2004. Eight women with abnormal results or test failure were excluded post-randomisation. INTERVENTIONS: Issuing karyotype results on a prespecified fixed date, rather than issuing them as soon as they became available. Issuing karyotype results alone, or subsequent to issuing results from a rapid molecular test for the most common chromosomal abnormalities. MAIN OUTCOME MEASURES: Average anxiety during the waiting period, calculated using daily scores from the short version of the Spielberger State-Trait Anxiety Inventory (STAI). Anxiety 1 month after receiving karyotype results, measured using the short form STAI. RESULTS: Issuing early results from a partial but rapid test reduced maternal anxiety by a clinically significant amount during the waiting period (mean daily score 12.5 versus 14.8; scale score difference -2.36, 95% CI -1.2, -3.6), compared with receiving only the full karyotype results. There was no evidence that giving out karyotype results on a fixed or on a variable date altered maternal anxiety during the waiting period (mean daily score 13.2 versus 14.2; scale score difference -1.02, 95% CI -2.2, 0.2). One month after receiving normal karyotype results, anxiety was low in all groups, but women who had been given rapid test results tended to be more anxious than those who had not (mean single day score 9.2 versus 8.3; mean scale score difference 0.95, 95% CI -0.03, 1.9). This small to moderate effect did not reach conventional levels of statistical significance. CONCLUSIONS: Rapid testing was a beneficial addition to karyotyping, at least in the short term. This does not necessarily imply that early results would be preferred to comprehensive ones if women had to choose between them. Because there are no clear advantages in anxiety terms of issuing karyotype results as soon as they become available, or on a fixed date, women could be given a choice between them.  相似文献   
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Calcitonin gene-related peptide (CGRP), the product of the calcitonin gene produced primarily in the central nervous system, has been shown to decrease food intake when administered intracerebroventricularly (ICV). Testing of CGRP (ICV) in both single bottle conditioned-aversion and differential starvation paradigms was done. In both paradigms, results using CGRP were consistent with those predicted for aversive agents. Therefore, CGRP apparently decreases feeding via aversive mechanisms.  相似文献   
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The lipolytic activity of β-lipotropin (β-LPH) is commonly supposed to reside in the heptapeptide sequence, 47–53. However, β-endorphin is also lipolytically active, so a second active sequence must be postulated. In attempts to define this second sequence, porcine β-LPH, β-endorphin, 19 partial sequences of β-LPH, [Leu]enkephalin, and [D-Met2, Pro5]-enkephalin amide have been examined for glycerol releasing activity in rabbit adipocytes. An N-terminal fragment of β-LPH lacking the 47–53 heptapeptide was inactive. The message within the C-terminal portion of β-LPH could be localized to a C-terminal sequence greater than 87–91, but probably smaller than 78–91.  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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An outbreak of Tunga Penetrans (Jigger Flea) infestation affecting a number of villages near to a Central Hospital in Malawi is described. Due to the large number of affected individuals, high parasitic load, and extended duration of infection an alternative to the recommended approach of surgical removal of the flea was required. Benzyl benzoate paint and liquid paraffin had been used in local Primary Healthcare settings previously and topical treatment with antiparasitic agents has been advocated in the literature, particularly for severe infestation. Benzyl benzoate and liquid paraffin were applied topically to four adults with numerous jigger flea burrows, and their progress assessed regularly. After completion of 7 days of treatment patients noted that fleas were dislodging spontaneously, and that embedded parasites had not increased in size to the same extent that untreated fleas had in previous infestations. Following confirmation of the viability of its implementation in a resource-poor setting, this treatment regimen has subsequently been adopted by the local branch of the District Health Office for distribution to infected communities.  相似文献   
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