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31.
From 1972 to 1979 34 patients with homozygous familial hypercholesterolaemia were seen in one clinic in Johannesburg. All were Afrikaners and most lived in Transvaal Province. Their epidemiological, genetic, clinical, and biochemical characteristics were studied. The course of the disease varied considerably among the 34 patients, with no fewer than six surviving into their fourth or fifth decades. In some patients arterial atheroma was severe while cutaneotendinous xanthomas were slight and vice versa. Coronary heart disease was common but peripheral and cerebral arterial disease was rare. Another prominent finding was high concentrations of low-density lipoprotein cholesterol coupled with low high-density lipoprotein cholesterol values. The prevalences of homozygotes and heterozygotes with familial hypercholesterolaemia in Transvaal Afrikaners, calculated from this group of patients, were 1 in 30,000 and 1 in 100 respectively. These figures are the highest ever reported and may help to explain why South African whites have the highest death rate from coronary heart disease in the Western world.  相似文献   
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A. Z. Joffe 《Mycopathologia》1969,37(2):150-160
Summary A comparative study was carried out in groundnut fields in Israel of the mycoflora of rhizosphere (R) and soil adhering to geocarps (G) and of the soil (S).Of a total of 157 fungal species isolated and listed, 133 occurred in R, 96 in S, and 86 in G. Ten species considered rare or worthy of special note are briefly discussed.Species ofAspergillus were most numerous in heavy soil, species ofPenicillium in light soil, and species ofFusarium in medium soil.Penicillium funiculosum andP. rubrum were the species occurring with greatest frequency, and these were equally common in R, S, and G of light and medium soil. Soil inoculation withA. flavus depressed the number of species in the mycoflora of R and S.Quantitative comparison of R, S, and G on the three soils showed that numbers for R exceeded those for S and G, forP. funiculosum andP. rubrum on all soils, and for several Aspergilli on heavy soil. Among fungi more prevalent in S than in R and G wasA. flavus on medium and heavy soil. No special affinity of any one of the 3 major groups (Aspergillus, Penicillium, Fusarium) for the mycoflorae of R or S or G has been found. The relative number of colonies of all fungi in R and S (R/S ratio) was in almost all cases in excess of 1 on all soil types.This research is supported by grant number FG-161 of the United States Department of Agriculture, to whom the author is indebted.  相似文献   
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The pattern of distribution of telomeric DNA (TTAGGG), 28S rDNA, and 5S rDNA has been studied using fluorescence in situ hybridization (FISH) and primed in situ labelling during spermatogenesis and sperm formation in the filiform spermatozoa of two species of planarians, Dendrocoelum lacteum and Polycelis tenuis (Turbellaria, Plathelminthes). In both species, the positions of FISH signals found with each probe sequence are constant from cell to cell in the nuclei of mature sperm. Chromosome regions containing 5S and 28S rDNA genes are gathered in distinct bundles of spiral form. In early spermatids with roundish nuclei, the sites of a given sequence on different chromosomes remain separate. Centromeres (marked by 5S rDNA) gather into a single cluster in the central region of the slightly elongated sperm nucleus. During spermatid maturation, this cluster migrates to the distal pole of the nucleus. In Polycelis, telomeric sites gather into three distinct clusters at both ends and in the middle of the moderately elongated nucleus. These clusters retain their relative positions as the spermatid matures. All the chromosome ends bearing 28S rDNA gather only into the proximal cluster. Our data suggest that structures in the nucleus selectively recognise chromosome regions containing specific DNA sequences, which helps these regions to find their regular places in the mature sperm nucleus and causes clustering of the sites of these sequences located on different chromosomes. This hypothesis is supported by observations on elongated sperm of other animals in which a correlation exists between ordered arrangement of chromosomes in the mature sperm nucleus and clustering of sites of the same sequence from different chromosomes during spermiogenesis. Received: 15 December 1997; in revised form: 24 March 1998 / Accepted: 14 April 1998  相似文献   
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Neuroscience research on sex difference is currently a controversial field, frequently accused of purveying a ‘neurosexism’ that functions to naturalise gender inequalities. However, there has been little empirical investigation of how information about neurobiological sex difference is interpreted within wider society. This paper presents a case study that tracks the journey of one high-profile study of neurobiological sex differences from its scientific publication through various layers of the public domain. A content analysis was performed to ascertain how the study was represented in five domains of communication: the original scientific article, a press release, the traditional news media, online reader comments and blog entries. Analysis suggested that scientific research on sex difference offers an opportunity to rehearse abiding cultural understandings of gender. In both scientific and popular contexts, traditional gender stereotypes were projected onto the novel scientific information, which was harnessed to demonstrate the factual truth and normative legitimacy of these beliefs. Though strains of misogyny were evident within the readers’ comments, most discussion of the study took pains to portray the sexes’ unique abilities as equal and ‘complementary’. However, this content often resembled a form of benevolent sexism, in which praise of women’s social-emotional skills compensated for their relegation from more esteemed trait-domains, such as rationality and productivity. The paper suggests that embedding these stereotype patterns in neuroscience may intensify their rhetorical potency by lending them the epistemic authority of science. It argues that the neuroscience of sex difference does not merely reflect, but can actively shape the gender norms of contemporary society.  相似文献   
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This is a study of the metabolic and distal cardiovascular/cerebrovascular outcomes associated with the use of second-generation antipsychotics (SGAs) compared to antidepressants (ADs) in adults aged 18-65 years, based on data from Thomson Reuters MarketScan® Research Databases 2006-2010, a commercial U.S. claims database. Interventions included clinicians'' choice treatment with SGAs (allowing any comedications) versus ADs (not allowing SGAs). The primary outcomes of interest were time to inpatient or outpatient claims for the following diagnoses within one year of SGA or AD discontinuation: hypertension, ischemic and hypertensive heart disease, cerebrovascular disease, diabetes mellitus, hyperlipidemia, and obesity. Secondary outcomes included the same diagnoses at last follow-up time point, i.e., not censoring observations at 365 days after SGA or AD discontinuation. Cox regression models, adjusted for age, gender, diagnosis of schizophrenia and mood disorders, and number of medical comorbidities, were run. Among 284,234 individuals, those within one year of exposure to SGAs versus ADs showed a higher risk of essential hypertension (adjusted hazard ratio, AHR+1.16, 95% CI: 1.12-1.21, p<0.0001), diabetes mellitus (AHR+1.43, CI: 1.33-1.53, p<0.0001), hypertensive heart disease (AHR+1.34, CI: 1.10-1.63, p<0.01), stroke (AHR+1.46, CI: 1.22-1.75, p<0.0001), coronary artery disease (AHR+1.17, CI: 1.05-1.30, p<0.01), and hyperlipidemia (AHR+1.12, CI: 1.07-1.17, p<0.0001). Unrestricted follow-up results were consistent with within one-year post-exposure results. Increased risk for stroke with SGAs has previously only been demonstrated in elderly patients, usually with dementia. This study documents, for the first time, a significantly increased risk for stroke and coronary artery disease in a non-elderly adult sample with SGA use. We also confirm a significant risk for adverse metabolic outcomes. These findings raise concerns about the longer-term safety of SGAs, given their widespread and chronic use.  相似文献   
40.

Background

Daily evaluation of multiple organ dysfunction syndrome has been performed in critically ill adults. We evaluated the clinical course of multiple organ dysfunction over time in critically ill children using the Pediatric Logistic Organ Dysfunction (PELOD) score and determined the optimal days for measuring scores.

Methods

We prospectively measured daily PELOD scores and calculated the change in scores over time for 1806 consecutive patients admitted to seven pediatric intensive care units (PICUs) between September 1998 and February 2000. To study the relationship between daily scores and mortality in the PICU, we evaluated changes in daily scores during the first four days; the mean rate of change in scores during the entire PICU stay between survivors and nonsurvivors; and Cox survival analyses using a change in PELOD score as a time-dependent covariate to determine the optimal days for measuring daily scores.

Results

The overall mortality among the 1806 patients was 6.4%. A high PELOD score (≥ 20 points) on day 1 was associated with an odds ratio (OR) for death of 40.7 (95% confidence interval [CI] 20.3–81.4); a medium score (10–19 points) on day 1 was associated with an OR for death of 4.2 (95% CI 2.0–8.7). Mortality was 50% when a high score on day 1 increased on day 2. The course of daily PELOD scores differed between survivors and nonsurvivors. A set of seven days (days 1, 2, 5, 8, 12, 16 and 18) was identified as the optimal period for measurement of daily PELOD scores.

Interpretation

PELOD scores indicating a worsening condition or no improvement over time were indicators of a poor prognosis in the PICU. A set of seven days for measurement of the PELOD score during the PICU stay provided optimal information on the progression of multiple-organ dysfunction syndrome in critically ill children.Almost all patients in intensive care units (ICUs) have some organ dysfunction.14 Adult and pediatric studies have shown that mortality increases with the number of organs involved.2,4,5 Thus, multiple-organ dysfunction syndrome (dysfunction involving two or more organs) has been viewed as the inexorable pathway to death.6 Primary multiple-organ dysfunction syndrome (present at admission or occurring within the first week after admission to the ICU) accounts for 88% of children with the syndrome; secondary multiple-organ dysfunction syndrome is less common (12%) but is associated with higher morbidity and mortality.7Organ dysfunction scores were first developed for use in critically ill adults to describe and quantify the severity of organ dysfunction, not to predict mortality. Two scores have been proposed for critically ill children: the Pediatric Logistic Organ Dysfunction (PELOD) score and the Pediatric Multiple Organ Dysfunction Score (P-MODS).810 These scores quantify organ dysfunction precisely and can be used as indicators of the severity of illness throughout the clinical course. They can also be used as baseline and outcome measures in clinical studies conducted in ICUs11,12 and pediatric ICUs (PICUs).13The PELOD score calculated with data collected over the entire PICU stay has been validated (using the most abnormal value of each variable during the entire PICU stay).10 However, the PELOD score over the entire PICU stay cannot be calculated before discharge from the unit; therefore, it cannot be used to characterize and follow the severity of organ dysfunction on a daily basis. Measurements repeated daily may provide more useful information.14 The optimal period for measuring daily scores for multiple organ dysfunction in adults has been studied.1517 Indeed, trends in the Sequential Organ Failure Assessment score over the first 48 hours in the ICU was found to be a sensitive indicator of outcome, with decreasing scores associated with a decrease in mortality from 50% to 27%.17 Similar data for critically ill children are lacking.We conducted this study to describe the clinical course of multiple organ dysfunction over time as measured by the daily PELOD score. Because the time and effort necessary to ensure accurate daily assessments and data entry can be substantial,18 we also aimed to determine the optimal days for measuring daily scores during the PICU stay.  相似文献   
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