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National factor(s) influencing publication output in the highest ranked medical journals are largely unknown. We sought to examine the relationship between national research funding and English proficiency on publication output. We identified all original research articles appearing in the five highest ranked general medical journals between 1997 and 2001. Using the country of the corresponding author as the source nation for each article, we determined a standardized publication rate across developed nations. We used multiple regression techniques to determine the influence of national expenditures on research and scores from the Test of English as a Foreign Language (TOEFL), a surrogate for English proficiency, on publication output. There was a significant relationship of national spending on research and TOEFL scores to publication output of developed countries (p = 0.04; p < 0.01, respectively). These two variables explained approximately 71.5% of the variation in publication rate across developed nations around the world (R = 0.85; p < 0.01). Normalized for population size, English-speaking nations and certain northern European countries such as Denmark, The Netherlands, Switzerland, and Sweden had the highest rate of publication in the five highest ranked general medical journals, while Asian countries had generally low rates of publication. Research spending and English proficiency were strongly associated with publication output in the highest ranked general medical journals. While these data cannot be considered definitive due to their observational nature, they do suggest that for English-language medical journals, research funding and English proficiency may be important determinants of publication. 相似文献
994.
Virus-specific RNA and antibody from convalescent-phase SARS patients discharged from hospital 总被引:2,自引:0,他引:2
Leong HN Chan KP Khan AS Oon L Se-Thoe SY Bai XL Yeo D Leo YS Ang B Ksiazek TG Ling AE 《Emerging infectious diseases》2004,10(10):1745-1750
Severe acute respiratory syndrome (SARS) is caused by a novel coronavirus (SARS-CoV). In a longitudinal cross-sectional study, we determined the prevalence of virus in bodily excretions and time of seroconversion in discharged patients with SARS. Conjunctival, throat, stool, and urine specimens were collected weekly from 64 patients and tested for SARS-CoV RNA by real-time polymerase chain reaction; serum samples were collected weekly and tested for SARS-CoV antibody with indirect enzyme immunoassay and immunofluorescence assay. In total, 126 conjunctival, 124 throat swab, 116 stool, and 124 urine specimens were analyzed. Five patients had positive stool samples, collected in weeks 5-9. Two patients seroconverted in weeks 7 and 8; the others were seropositive at the first serum sample collection. In this study, 5 (7.8%) of 64 patients continued to shed viral RNA in stool samples only, for up to week 8 of illness. Most seroconversions occurred by week 6 of illness. 相似文献
995.
G protein-coupled receptors GPR4 and TDAG8 are oncogenic and overexpressed in human cancers 总被引:2,自引:0,他引:2
Sin WC Zhang Y Zhong W Adhikarakunnathu S Powers S Hoey T An S Yang J 《Oncogene》2004,23(37):6299-6303
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The addition of second trimester serum markers to maternal age increases the efficacy of screening for Down syndrome by maternal age alone. Among women aged 35 years or older, serum screening makes a large proportion of amniocentesis unnecessary. However, there are ethical and medicolegal concerns about serum screening in 'old' women, largely because some of the pregnancies affected by Down syndrome and other chromosomal abnormalities may not be detected. We investigated the acceptability of serum screening in women aged 35 years or older when it was offered as an alternative to prenatal cytogenetic diagnosis after detailed counselling. Women referred for prenatal diagnosis of Down syndrome because of advanced maternal age were given the options of cytogenetic diagnosis by chorionic villus sampling (CVS) or amniocentesis. As an alternative, they could choose to undergo second trimester serum human chorionic gonadotrophin (hCG) and alpha-fetoprotein (AFP) screening first before deciding on whether to undergo amniocentesis. Between January 1997 and October 1999, 3419 subjects were recruited. 1807 women (52. 9%) chose to undergo serum screening, 1516 women (44.3%) chose to have amniocentesis and 96 women chose to have CVS (2.8%). The proportion of women who chose serum screening rose steadily from 38. 8% in the year of 1997 to 63.4% in 1999. Significantly fewer Chinese women chose serum screening than non-Chinese. The decision as to whether to undergo an invasive diagnostic procedure or to be content with the relatively safer but less accurate screening test varies, being affected by the women's background and culture. 相似文献
999.
Glycogen storage disease type 1b (GSD1b) is an autosomal recessive inborn error of metabolism caused by deficiency of glucose-6-phosphate translocase (G6PT1). Current laboratory diagnosis for GSD1b is established by a functional enzyme assay of glucose-6-phosphatase in both fresh and detergent-treated liver homogenates. This procedure requires liver biopsy and is impractical for routine prenatal diagnosis owing to the high morbidity of fetal liver biopsy. Recently, the gene for GSD1b has been cloned and the prevalent mutations in different ethnic groups have been determined. In this study, prenatal molecular diagnosis was performed for a Chinese family in which a previous child was born homozygous for the G149E mutation. We detected genomic sequence variants by heteroduplex formation, followed by denaturing high performance liquid chromatography (DHPLC). With this method, post-PCR analysis was shortened to 7 min. In the case we analysed, PCR products amplified from the fetal DNA yielded a single peak in the chromatogram, indicating a homozygous state in the fetus. When wild-type PCR products were mixed with fetal PCR products, two peaks were observed, indicating that the fetus was homozygous for the parental (G149E) mutation. Sequencing results confirmed this diagnosis. As a result, the pregnancy was terminated and the diagnosis was confirmed on DNA analysis of the aborted fetus. We show here that DNA mutation analysis can be used in the prenatal diagnosis of GSD1b and that DHPLC promises to be a robust technique for this and other prenatal molecular diagnoses. 相似文献
1000.
Despite the temporal trend toward decreasing length of hospital stay for all medical conditions in North America, the effect of different lengths of hospitalization on short-term outcomes such as readmission or mortality has not been well studied. However, there is growing concern that very short stays in hospital may result in premature discharges, which may lead to worse outcomes for patients. We conducted a population-based study of elderly patients with obstructive airway disease in Ontario, Canada to test the hypothesis that very short initial hospital stays increase the short-term risk for readmission and mortality. Using a cohort of 32,384 elderly patients 65 yr of age or older, we compared 15-d rates of readmission and mortality among patients with different lengths of stay. Although patients with hospital stays of less than 4 d were younger and had fewer comorbidities, they were 39% (95% confidence interval [CI], 20% to 61%) more likely to be readmitted and 45% (95% CI, 9% to 92%) more likely to die within 15 d postdischarge compared with those who stayed 4 to 6 d. The risk was highest among patients whose stay was less than or equal to 1 hospital day; they had a 69% (95% CI, 32% to 117%) excess risk of readmission and a 2.08 (95% CI, 1.23 to 3.45) -fold increase in mortality compared with those who stayed in hospital for 2 d. This suggests that some elderly patients with obstructive airway disease may be being prematurely discharged. 相似文献