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Barden A Beilin LJ Both K Ritchie J Leedman P Walters BN Michael CA 《Clinical science (London, England : 1979)》1999,97(6):697-706
In order to evaluate whether lipid abnormalities may contribute to endothelial dysfunction in pre-eclampsia, the present study examined the in vitro effects of very-low-density lipoprotein (VLDL), low-density lipoprotein (LDL) and high-density lipoprotein (HDL), isolated from women with pre-eclampsia and matched controls, on the endothelial synthesis of 6-oxo-prostaglandin F(1alpha) (6-oxo-PGF(1alpha); a metabolite of prostacyclin) and endothelin 1, and on the expression of nitric oxide synthase 3 (NOS3) mRNA. VLDL, LDL and HDL cholesterol were isolated from 20 pre-eclamptic and 20 age- and gestation-matched normal pregnant women. The lipoproteins (50 microgram/ml) and lipoprotein-free control plasma were incubated for 1, 3 and 6 h at 37 degrees C with a human umbilical endothelial cell line. The synthesis of 6-oxo-PGF(1alpha) and endothelin 1, and NOS3 mRNA expression, were measured at each time point. VLDL from pre-eclamptic women stimulated endothelial cell 6-oxo-PGF(1alpha) synthesis to a lesser extent than that from normal pregnant women (P<0.05). LDL from women with pre-eclampsia also stimulated 6-oxo-PGF(1alpha) synthesis to a lesser extent than LDL from normal pregnant women, but the effect was less sustained. The effect of HDL from women with pre-eclampsia on 6-oxo-PGF(1alpha) synthesis was similar to that of HDL from normal pregnant women. The pre-incubation levels of lipid peroxides in VLDL and LDL were not different between the normal pregnant and pre-eclamptic women, and cannot account for the decrease in 6-oxo-PGF(1alpha) synthesis. VLDL, LDL and HDL from women with pre-eclampsia did not affect endothelial cell synthesis of endothelin 1 or expression of NOS3 mRNA differently from lipoproteins from normal pregnant women. This study suggests that VLDL, and to a lesser extent LDL, from women with pre-eclampsia could potentially contribute to the reduced systemic 6-oxo-PGF(1alpha) synthesis observed in the pre-eclamptic syndrome. 相似文献
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Objectives: To describe changes in the case mix, demographics, waiting times (WTs; time from arrival in the emergency department (ED) until seen by a clinician) and treatment times (TTs; time from seeing a clinician until leaving the ED) of adult patients presenting to the EDs in Sheffield, UK, between 1993 and 2003. Design: A retrospective analysis of routinely collected data. Results: Of a total of 252 156 patients included in the study, the proportion of attendees aged 16–29 years decreased from 38.7% in 1993 to 28.8% in 2003 (rate of change (b) = –1.10% per year, 95% CI –1.20% to –0.82%, p<0.001) whereas the proportion aged 80–99 years increased from 6.2% to 10.4% (b = 0.37% per year, 95% CI 0.29% to 0.45%, p<0.001). The proportion of "minors" (patients not arriving by ambulance and subsequently discharged) fell from 71.1% in 1993 to 60.8% in 2003 (b = –1.04% per year, 95% CI –1.36% to –0.73%, p<0.001). WTs increased from a median of 21 minutes in 1993 to 48 minutes in 2003 (b = 3.5 min per year, 95% CI 2.23 min to 4.77 min, p<0.001). The median TT for minors was unchanged but that for majors (patients arriving by ambulance and admitted to hospital from the ED) increased from 55 to 205 minutes (b = 11.55 min per year, 95% CI 6.54 min to 16.55 mins, p = 0.01). Conclusion: The demographics, case mix, and waiting times of patients presenting to EDs in Sheffield changed considerably over an 11 year period. There is evidence that the service for minor case patients improved slightly at the end of the period studied, but this is possibly at the expense of a deteriorating experience for major case patients. 相似文献
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Heinrich C. Weber Eugene Haydn Walters Mai Frandsen Shyamali C. Dharmage 《The Journal of asthma》2013,50(10):1062-1069
Objective: Asthma and allergic diseases are poorly described in rural areas. The objective of this study was, therefore, to determine the prevalence of wheezing, asthma, and other allergic disorders among children living in regional and rural Tasmania. Methodology: Data from a cross-sectional survey using standardized questionnaires of asthma, allergic conditions and food allergies were collected from 39 primary schools across North West Tasmania. We enrolled 1075 children between 6 and 8?years. The main outcomes were prevalences of wheezing, asthma, and other allergic disorders further stratified by sex and indigenous status. Results: Baseline characteristics were as follows: median age 8.1?years (IQR: 7.6, 8.7) with equal sex distribution, most (80.1%) attended public schools and 11.0% identified as indigenous. We report prevalences of current wheezing (22.7%), allergic rhinoconjunctivitis (16.3%) and atopic eczema (16.6%), with higher prevalences among boys (except eczema). Food allergies were reported in 8.6% and food-related anaphylaxis in 1.6% of the sample. Indigenous children had significantly higher prevalence of current wheezing (indigenous 31.1% versus non-indigenous 21.6%; p?=?0.02). Further, children with current wheezing and no asthma diagnosis, had similar prevalence of other atopic diseases (hayfever 31.4%, eczema 44.0%, and food reaction 23.2%) compared with diagnosed asthmatics, although likely shared the illness. Conclusions: Childhood asthma is more prevalent in regional Tasmania compared with national estimates, especially among indigenous children. This appears not to be driven by an allergic response. Also, a significant proportion of children are likely to have undiagnosed asthma which has implications for rural health service delivery. 相似文献
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The Cognitive Skills Program at the Albert Einstein College of Medicine has identified 1% to 2% of students from several classes whose learning disabilities were previously undiagnosed. In three case studies, the importance of early identification and support during the preclinical years—and the impact of diagnosis, evaluation, and intervention—are illustrated. In each case, there was a dramatic improvement in performance when the student was made aware of his or her learning disability and when appropriate intervention was provided. 相似文献
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L. Daniel Maxim John Allshouse Richard E. Fairfax T. J. Lentz Dean Venturin Thomas E. Walters 《Inhalation toxicology》2013,25(3):289-309
This article presents a 17-year (1990–2006) retrospective summary of ongoing studies of occupational exposure to refractory ceramic fiber (RCF) in the United States. Beginning in 1990, RCF producers integrated and harmonized individual workplace monitoring programs to provide data useful for various longitudinal and cross-sectional analyses, benchmarking, and various technical analyses. For 10 of these 17 years, the program has been conducted in partnership with government agencies, first a 5-year (1993–1998) program with the U.S. Environmental Protection Agency and later another 5-year (2002–2006) program with the Occupational Safety and Health Administration and the National Institute for Occupational Safety and Health. This article updates earlier published studies and provides lessons to be learned in the design of industrial hygiene monitoring and control programs. 相似文献
49.
S. Wayne Miles Janie Sheridan Bruce Russell Rob Kydd Amanda Wheeler Carina Walters Greg Gamble Peta Hardley Maree Jensen Kimmo Kuoppasalmi Pekka Tuomola Jaana Föhr Outi Kuikanmäki Helena Vorma Raimo Salokangas Antti Mikkonen Mika Kallio Jussi Kauhanen Vesa Kiviniemi Jari Tiihonen 《Addiction (Abingdon, England)》2013,108(7):1279-1286
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