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OBJECTIVE: Because survival from admission to discharge does not provide parents and physicians information about future life expectancy in the premature neonate, we characterized the actuarial survival, defined as the future life expectancy from a given postnatal age, in a large inborn population of premature infants < 30 weeks' gestation. STUDY DESIGN: We determined daily actuarial survival of 1925 inborn infants (23 to 29 weeks' gestation) admitted to the Baylor Affiliated Nurseries from July 1986 through December 1994, stratified by 100-g birth weight and by 1-week gestational-age intervals. RESULTS: In the 501- to 600-g birth weight stratum, actuarial survival improved from 31% at birth, to 61% on day of life 7, and then to 75% on day of life 28; in the 901- to 1000-g birth weight stratum, actuarial survival improved from 88%, to 94%, and then to 98% throughout the same times, respectively. Similar trends were obtained when data were stratified by gestational age. CONCLUSIONS: Survival in the smallest infants improves dramatically during the first few days of life, but there is a significant risk for late death in the smallest of these infants. 相似文献
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Gonzales AJ; Christensen JG; Preston RJ; Goldsworthy TL; Tlsty TD; Fox TR 《Carcinogenesis》1998,19(7):1173-1183
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Pedersen ME Vestergaard HT Stafford GI van Staden J Jäger AK 《Journal of ethnopharmacology》2008,119(3):538-541
ETHNOPHARMACOLOGICAL RELEVANCE: Searsia dentata and Searsia pyroides are used in traditional South African medicine to treat convulsions and epilepsy. Previous studies have demonstrated that extracts of these plants comprise compounds that bind to the flumazenil-sensitive site on the GABA(A) receptor. However, their use as anticonvulsant medicinal plants cannot be adequately explained by these findings. AIMS: The aim of this study was to examine the possible involvement of the glutamatergic system of extracts from the plants. MATERIALS AND METHODS: The mouse cortical wedge preparation was used for functional characterization of the extracts. The affinity towards the NMDA and the AMPA receptor was investigated using classical [(3)H]-GP39653 and [(3)H]-AMPA binding assays, respectively. RESULTS: The extracts of Searsia dentata and Searsia pyroides inhibited the spontaneous epileptiform discharges in mouse cerebral cortical slices with ED(50) of 0.62 and 1.67mg dry extract/mL, respectively. Both extracts displaced [(3)H]-GP39653 binding and significantly inhibited the NMDA-induced response during co-administration in cortical slices. CONCLUSION: In this study, the NMDA receptor antagonistic effect of the crude ethanolic extracts of these two South African medicinal plants was demonstrated. 相似文献
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Line Due Christensen Claus Hstrup Vestergaard Morten Bondo Christensen Linda Huibers 《Scandinavian journal of primary health care》2022,40(1):115
ObjectiveTo investigate the correlation between having designated general practitioners (GPs) in residential care homes and the residents’ number of contacts with primary care, number of hospital admissions and mortality.DesignA retrospective register-based longitudinal study.SettingForty-two care homes in Aarhus Municipality, Denmark.SubjectsA total of 2376 care home residents in the period from 1 September 2016 to 31 December 2018.Main outcome measuresWe used two models to calculate the incidence risk ratio (IRR) for primary care contacts, hospital admission or dying. Model 1 compared the residents’ risk time before with their risk time after implementation of the designated GP model. Model 2 included only risk time after implementation and was based on calculations of successful (rate ≥60%) implementation.ResultsWeighted by time at risk, the proportion of females across the two models ranged from 64% to 68%. The largest group was aged ‘85-94’ years. In Model 1, the mere implementation of the model did not correlate with changes in primary care contacts, hospital admissions, or mortality. Contrarily, in Model 2, residents living in care homes with successful implementation had fewer email contacts (IRR = 0.81, 95%CI: 0.68;0.96), fewer telephone contacts (IRR = 0.78, 95%CI: 0.68;0.90) and fewer hospital admissions (IRR = 0.85, 95%CI: 0.73;0.99), but more home visits (IRR = 1.70, 95%CI: 1.29;2.25) than residents living in care homes with lower implementation rates.ConclusionThe designated GP model seems promising, as a high implementation degree of the model correlated with a reduced the number of acute admissions, short-term admissions and readmissions. Future studies should focus on gaining deeper insight into the mechanisms of the designated GP model to further optimize the model.
Key points
- A new care model was introduced in Denmark in 2017, designating dedicated GPs to residential care homes for the elderly.
- Successful implementation correlated with significantly fewer hospital admissions, specifically for acute admissions, but also with fewer short-term admissions and readmissions.
- The implementation of the model correlated significantly with fewer e-mail and telephone contacts and with more home visits.
- Future studies should gain more insight into the mechanisms of the designated GP model to further optimize the model.
18.
Phase 2 reentry in man. 总被引:3,自引:0,他引:3
Poul Erik Bloch Thomsen Rikke Moerch Joergensen J?rgen Kim Kanters Thomas Jon Jensen Jens Haarbo Arne Hagemann Annette Vestergaard Knud Saermark 《Heart rhythm》2005,2(8):797-803
BACKGROUND: Ventricular extrasystoles are characterized by a fixed coupling interval to the last QRST complex preceding it. OBJECTIVES: We hypothesized that this QRST complex differed from QRST complexes of other sinus beats not followed by ventricular extrasystoles. Further, we investigated whether phase 2 reentry, demonstrated in animal experiments to initiate ventricular extrasystoles, ventricular tachycardia, and ventricular fibrillation, also plays a role in humans. METHODS: We examined 18 patients with ventricular extrasystoles and/or ventricular tachycardia by signal averaging of the ECG (group A) or by single-beat analysis of intracardiac electrograms (group B). Group A consisted of six patients without structural heart disease and one patient with the Brugada syndrome. Six of the seven patients had right ventricular outflow tract ventricular extrasystoles. Group B consisted of 11 patients undergoing radiofrequency ablation. Eight of the 11 patients had right ventricular outflow tract extrasystoles. RESULTS: In six of the seven patients in group A, we demonstrated significant ST-elevation and/or T-wave changes in the sinus beat preceding ventricular extrasystoles compared with the second last sinus beat in one or more of the three orthogonal leads X, Y, and Z. In 9 of the 11 patients in group B, single-beat analysis of unipolar and bipolar electrograms recorded close to successful ablation sites demonstrated similar changes, that is, ST-elevation (median peak voltage gradient 150 muV, range 0-1,700) and T-wave changes in the sinus beat prior to ventricular ectopy. In addition, J-point elevation was demonstrated in several cases. In total, significant changes were demonstrated in 15 of the 18 patients studied (83%). CONCLUSION: J-point elevation, ST-elevation, and T-wave changes documented in the last sinus beat prior to ventricular extrasystoles are in agreement with phase 2 reentry, suggesting that this may be the responsible mechanism for ventricular extrasystoles and ventricular tachycardia/fibrillation. The phenomenon has been demonstrated in only animal experiments to date. 相似文献
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Acute effects of ghrelin administration on glucose and lipid metabolism 总被引:11,自引:0,他引:11
Vestergaard ET Djurhuus CB Gjedsted J Nielsen S Møller N Holst JJ Jørgensen JO Schmitz O 《The Journal of clinical endocrinology and metabolism》2008,93(2):438-444
CONTEXT: Ghrelin infusion increases plasma glucose and nonesterified fatty acids, but it is uncertain whether this is secondary to the concomitant release of GH. OBJECTIVE: Our objective was to study direct effects of ghrelin on substrate metabolism. DESIGN: This was a randomized, single-blind, placebo-controlled two-period crossover study. SETTING: The study was performed in a university clinical research laboratory. PARTICIPANTS: Eight healthy men aged 27.2 +/- 0.9 yr with a body mass index of 23.4 +/- 0.5 kg/m(2) were included in the study. INTERVENTION: Subjects received infusion of ghrelin (5 pmol x kg(-1) x min(-1)) or placebo for 5 h together with a pancreatic clamp (somatostatin 330 microg x h(-1), insulin 0.1 mU x kg(-1) x min(-1), GH 2 ng x kg(-1) x min(-1), and glucagon 0.5 ng.kg(-1) x min(-1)). A hyperinsulinemic (0.6 mU x kg(-1) x min(-1)) euglycemic clamp was performed during the final 2 h of each infusion. RESULTS: Basal and insulin-stimulated glucose disposal decreased with ghrelin [basal: 1.9 +/- 0.1 (ghrelin) vs. 2.3 +/- 0.1 mg x kg(-1) x min(-1), P = 0.03; clamp: 3.9 +/- 0.6 (ghrelin) vs. 6.1 +/- 0.5 mg x kg(-1) x min(-1), P = 0.02], whereas endogenous glucose production was similar. Glucose infusion rate during the clamp was reduced by ghrelin [4.0 +/- 0.7 (ghrelin) vs. 6.9 +/- 0.9 mg.kg(-1) x min(-1); P = 0.007], whereas nonesterified fatty acid flux increased [131 +/- 26 (ghrelin) vs. 69 +/- 5 micromol/min; P = 0.048] in the basal period. Regional lipolysis (skeletal muscle, sc fat) increased insignificantly with ghrelin infusion. Energy expenditure during the clamp decreased after ghrelin infusion [1539 +/- 28 (ghrelin) vs. 1608 +/- 32 kcal/24 h; P = 0.048], but the respiratory quotient did not differ. Minor but significant elevations in serum levels of GH and cortisol were observed after ghrelin infusion. CONCLUSIONS: Administration of exogenous ghrelin causes insulin resistance in muscle and stimulates lipolysis; these effects are likely to be direct, although a small contribution of GH and cortisol cannot be excluded. 相似文献