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61.
辽吉冰凉花总甙对心功能影响的实验研究 总被引:3,自引:0,他引:3
辽吉冰凉花总甙(APAW)1.0mg/kg iv,能使麻醉家兔正常心脏的P-dP/dt环体面积(LO),LV-dP/dtmax,Vpm及LVSP比药前增大,HR减慢。APAW和冰凉花(AAR)及毒毛旋花子甙K(SK)一样,能明显改善衰竭兔心的心功能。静脉恒速输入0.5 mg/ml APAW,25min后,心衰家兔的LVSP,LV—dP/dt max,LO均明显回升,LVEDP降低,t-dP/dt max缩短。三种强心甙的最大强心效力无显著性差异。但APAW的治疗宽度和治疗指数均较AAR和SK为大,而AAR和SK间则无显著性差异。 相似文献
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Rebecka Peebles Jenny L Wilson Iris F Litt Kristina K Hardy James D Lock Julia R Mann Dina LG Borzekowski 《Journal of medical Internet research》2012,14(5)
Background
Much concern has been raised over pro-eating disorder (pro-ED) website communities, but little quantitative research has been conducted on these websites and their users.Objective
To examine associations between levels of pro-ED website usage, disordered eating behaviors, and quality of life.Methods
We conducted a cross-sectional, Internet-based survey of adult pro-ED website users. Main outcomes were Eating Disorder Examination Questionnaire (EDE-Q) and Eating Disorder Quality of Life (EDQOL) scores.Results
We included responses from 1291 participants; 1254 (97.13%) participants were female. Participants had an average age of 22.0 years and a mean body mass index of 22.1 kg/m2; 24.83% (296/1192) were underweight; 20.89% (249/1192) were overweight or obese. Over 70% of participants had purged, binged, or used laxatives to control their weight; only 12.91% (163/1263) were in treatment. Mean EDE-Q scores were above the 90th percentile and mean EDQOL scores were in the severely impaired range. When compared with moderate and light usage, heavy pro-ED website usage was associated with higher EDE-Q global (4.89 vs 4.56 for medium and 4.0 for light usage, P < .001) and EDQOL total scores (1.64 vs 1.45 for medium and 1.25 for light usage, P < .001), and more extreme weight loss behaviors and harmful post-website usage activities. In a multivariate model, the level of pro-ED website usage remained a significant predictor of EDE-Q scores.Conclusions
Pro-ED website visitors reported many disordered eating behaviors, although few had been treated. Heavy users reported poorer quality of life and more disordered eating behaviors. 相似文献64.
S Thavagnanam SN Christie GM Doherty PV Coyle MD Shields LG Heaney 《Acta paediatrica (Oslo, Norway : 1992)》2010,99(3):394-398
Aim: The aim of this study was to determine if asthmatic children have viruses more commonly detected in lower airways during asymptomatic periods than normal children. Methods: Fifty‐five asymptomatic children attending elective surgical procedures (14 with stable asthma, 41 normal controls) underwent non‐bronchoscopic bronchoalveolar lavage. Differential cell count and PCR for 13 common viruses were performed. Results: Nineteen (35%) children were positive for at least one virus, with adenovirus being most common. No differences in the proportion of viruses detected were seen between asthmatic and normal ‘control’ children. Viruses other than adenovirus were associated with higher neutrophil counts, suggesting that they caused an inflammatory response in both asthmatics and controls (median BAL neutrophil count, 6.9% for virus detected vs. 1.5% for virus not detected, p = 0.03). Conclusions: Over one‐third of asymptomatic children have a detectable virus (most commonly adenovirus) in the lower airway; however, this was not more common in asthmatics. Viruses other than adenovirus were associated with elevated neutrophils suggesting that viral infection can be present during relatively asymptomatic periods in asthmatic children. 相似文献
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Mutation of E1 glycoprotein of classical swine fever virus affects viral virulence in swine 总被引:4,自引:0,他引:4
Risatti GR Holinka LG Lu Z Kutish GF Tulman ER French RA Sur JH Rock DL Borca MV 《Virology》2005,343(1):116-127
Transposon linker insertion mutagenesis of a full-length infectious clone (IC) (pBIC) of the pathogenic classical swine fever virus (CSFV) strain Brescia was used to identify genetic determinants of CSFV virulence and host range. Here, we characterize a virus mutant, RB-C22v, possessing a 19-residue insertion at the carboxyl terminus of E1 glycoprotein. Although RB-C22v exhibited normal growth characteristics in primary porcine macrophage cell cultures, the major target cell of CSFV in vivo, it was markedly attenuated in swine. All RB-C22v-infected pigs survived infection remaining clinically normal in contrast to the 100% mortality observed for BICv-infected animals. Comparative pathogenesis studies demonstrated a delay in RB-C22v spread to, and decreased replication in the tonsils, a 10(2) to 10(7) log10 reduction in virus titers in lymphoid tissues and blood, and an overall delay in generalization of infection relative to BICv. Notably, RB-C22v-infected animals were protected from clinical disease when challenged with pathogenic BICv at 3, 5, 7, and 21 days post-RB-C22v inoculation. Viremia, viral replication in tissues, and oronasal shedding were reduced in animals challenged at 7 and 21 DPI. Notably BICv-specific RNA was not detected in tonsils of challenged animals. These results indicate that a carboxyl-terminal domain of E1 glycoprotein affects virulence of CSFV in swine, and they demonstrate that mutation of this domain provides the basis for a rationally designed and efficacious live-attenuated CSF vaccine. 相似文献
70.
LG Frankenthal 《MedR Medizinrecht》1999,17(4):184-186
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